Skip to content Skip to navigation

Marc R. Safran, MD

Professor of Orthopaedic Surgery at the Stanford University Medical Center

Orthopaedic Surgery
Sports Medicine
Hip Arthroscopy
Elbow Surgery
Ligament Reconstruction
Knee Surgery
Knee Arthroscopy
Shoulder Surgery
Shoulder Dislocation
Hip Impingement
Labral Tears
Shoulder Impingement Syndrome
Thrower's Shoulder
Thrower's Elbow
Knee Injuries
Elbow Arthroscopy
Academic Appointments: 
Professor - Med Center Line, Orthopaedic Surgery
Administrative Appointments: 
Board Member, Chair Council of Delegates, American Orthopaedic Society for Sports Medicine (2012 - 2014)
Vice President, International Society for Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) (2013 - 2017)
Vice President, International Society for Hip Arthroscopy (ISHA) (2014 - 2015)
Chief Orthopaedic Consultant, Women's Tennis Association (WTA) (2011 - Present)
Honors and Awards: 
American Heart Association Student Research Fellowship, American Heart Association (1982)
Honor Student Society, UC Berkeley (1979-1983)
Magna Cum Laude, UC Berkeley (1983)
Best Resident's Paper, 3RD Place, Am. Acad. Ped., Orthop. Section (1990)
Best Resident's Paper, 1ST Place, Western Orthopaedic Association (1993)
Best Clinical Science Fellow's Paper, 1ST Place, University of Pittsburgh (1994)
American College of Sports Medicine (ACSM) Clinical Exchange Scholar, American College of Sports Medicine (ACSM) (2001)
American Orthopaedic Society for Sports Medicine (AOSSM) International Traveling Fellow, American Orthopaedic Society for Sports Medicine (AOSSM) (2002)
Irving Glick Award, Physician of the Year, Sanex WTA Tour (2001)
Guest Reviewer, Aircast Foundation Granting Board (2004)
Professional Organizations: 
Vice President, International Society of Hip Arthroscopy (2014 - 2015)
President, International Society of Hip Arthroscopy (2015)
Vice President, International Society for Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (2013 - Present)
Editorial Board, American Journal of Sports Medicine (2002 - Present)
Deputy Editor, Journal of Hip Preservation Surgery (2014 - Present)
Board Member, Chair, Council of Delegates, American Orthopaedic Society for Sports Medicine (2012 - 2014)
Internship:UCLA Registrar (1988) CA
Fellowship:University of Pittsburgh (1994) PA
Board Certification: Orthopaedic Surgery, American Board of Orthopaedic Surgery (1996)
Board Certification: Sports Medicine, American Board of Orthopaedic Surgery (2007)
Medical Education:Duke University School of Medicine (1987) NC
MD, University of Pittsburgh, Sports Med. & Shoulder Surgery (1994)
MD, UCLA, Orthopaedic Surgery (1993)
M.D., Duke University (1987)
Community and International Work: 
Evaluation of Hip Kinematic in Cadaver Model, Stanford
PreOp 3D Computer Simulation Improve Clinical Outcomes of Arthroscopic Surgery for FAI, Stanford, London
Academic and Contact Information
Alternate Contact: 
Alternate Contact
Clinical Offices: 
Clinical Practices: 
Research & Scholarship
Current Research Interests: 
Dr. Safran is the Associate Chief of Sports Medicine and Fellowship Director of Sports Medicine, Professor of Orthopaedic Surgery. Dr. Safran specializes in Sports Medicine and arthroscopic and ligament reconstructive surgery on the shoulder, elbow, hip and knee. He is a diplomat at the American Board of Orthopaedic Surgery and member of such prestigious societies such as: The American Orthopaedic Society for Sports Medicine, the ACL Study Group, the American Shoulder and Elbow Surgeons Society, the Paradicus Society, the Multicenter of Arthroscopic Hip Surgery Outcomes Research Network, the Multicenter Orthopaedic Outcomes Network, and the Society of Tennis Medicine and Science in addition to the American College of Sports Medicine. Dr. Safran’s practice focuses on arthroscopic management of hip problems as well as articular cartilage regeneration, shoulder surgery and athletic shoulder and elbow problems. He is actively involved in research in these areas. Dr. Safran graduated from the University of California, Berkeley; Medical School was at Duke University; Residency at Uuniversity of California, Los Angeles; and Sports Medicine and Shoulder Surgery Fellowship from the University of Pittsburg. He has served as a team physician for many collegiate teams since 1993, in addition to being actively involved with professional tennis and as a consultant for the NBA Players Association. Dr. Safran has authored or co-authored more than 75 scientific articles, 40 book chapters and three books on sports medicine as it relates to the shoulder, elbow, knee, hip as well as tennis injuries and biomechanics cartilage research. Prior to coming to Stanford in the Spring of 2007, Dr. Safran has been in different practices, including being the Chief of Sports Medicine at the University of California, San Francisco, where he also served as a team physician for the University of California, Berkeley. He is on the editorial board of many journals, including the American Journal of Sports Medicine.
Does PreOperative 3D Computer Simulation Improve Clinical Outcomes of Arthroscopic Surgery for FAI, Stanford University and London, England (June 30, 2013 - 12/31/2015)
Does PreOperative 3D Computer Simulation Improve Clinical Outcomes of Arthroscopic Surgery for FAI

This is a prospective, randomized, multicenter study, involving Stanford and London, England evaluating the efficacy of pre-operative planning for femoroacetabular (FAI) arthroscopic surgery using novel computer simulation software (from the Netherlands) to plan surgery for patients with FAI


Stanford University and London, England

Evaluation of Hip Kinematic in Cadaver Model, Stanford University and Rizzoli Institute, Bologna, Italy (2007 - 2007)
Evaluation of Hip Kinematic in Cadaver Model

This was a study of hip kinematics performed at Stanford University and the PAlo Alto Veteran's Administration Hospital / Bone and Joint Research Center, using technology developed at the Rizzoli Institute in Bologna, Italy. Cadaveric hips were studied to better understand hip function and motion.


Stanford University and Bologna, Italy

Courses Taught: 
Academic Year: 
Independent Study Courses: 
Directed Reading in Orthopedic Surgery
ORTHO 299 (Aut, Win, Spr, Sum)
Graduate Research
ORTHO 399 (Aut, Win, Spr, Sum)
Medical Scholars Research
ORTHO 370 (Aut, Win, Spr, Sum)
Undergraduate Research
ORTHO 199 (Aut, Win, Spr, Sum)
High Incidence of Infraspinatus Muscle Atrophy in Elite Professional Female Tennis Players AMERICAN JOURNAL OF SPORTS MEDICINE Young, S. W., Dakic, J., Stroia, K., Nguyen, M. L., Harris, A. H., Safran, M. R. 2015; 43 (8): 1989-1993


Isolated infraspinatus muscle atrophy is common in overhead athletes, who place significant and repetitive stresses across their dominant shoulders. Studies on volleyball and baseball players report infraspinatus atrophy in 4% to 34% of players; however, the prevalence of infraspinatus atrophy in professional tennis players has not been reported.To investigate the incidence of isolated infraspinatus atrophy in professional tennis players and to identify any correlations with other physical examination findings, ranking performance, and concurrent shoulder injuries.Cross-sectional study; Level of evidence, 3.A total of 125 professional female tennis players underwent a comprehensive preparticipation physical health status examination. Two orthopaedic surgeons examined the shoulders of all players and obtained digital goniometric measurements of range of motion (ROM). Infraspinatus atrophy was defined as loss of soft tissue bulk in the infraspinatus scapula fossa (and increased prominence of dorsal scapular bony anatomy) of the dominant shoulder with clear asymmetry when compared with the contralateral side. Correlations were examined between infraspinatus atrophy and concurrent shoulder disorders, clinical examination findings, ROM, glenohumeral internal rotation deficit, singles tennis ranking, and age.There were 65 players (52%) with evidence of infraspinatus atrophy in their dominant shoulders. No wasting was noted in the nondominant shoulder of any player. No statistically significant differences were seen in mean age, left- or right-hand dominance, height, weight, or body mass index for players with or without atrophy. Of the 77 players ranked in the top 100, 58% had clinical infraspinatus atrophy, compared with 40% of players ranked outside the top 100. No associations were found with static physical examination findings (scapular dyskinesis, ROM glenohumeral internal rotation deficit, postural abnormalities), concurrent shoulder disorders, or compromised performance when measured by singles ranking.This study reports a high level of clinical infraspinatus atrophy in the dominant shoulder of elite female tennis players. Infraspinatus atrophy was associated with a higher performance ranking, and no functional deficits or associations with concurrent shoulder disorders were found. Team physicians can be reassured that infraspinatus atrophy is a common finding in high-performing tennis players and, if asymptomatic, does not appear to significantly compromise performance.

View details for DOI 10.1177/0363546515588177

View details for Web of Science ID 000358892400026

View details for PubMedID 26078449

Biochemical and Cellular Assessment of Acetabular Chondral Flaps Identified During Hip Arthroscopy ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY Hariri, S., Truntzer, J., Smith, R. L., Safran, M. R. 2015; 31 (6): 1077-1083


To analyze chondral flaps debrided during hip arthroscopy to determine their biochemical and cellular composition.Thirty-one full-thickness acetabular chondral flaps were collected during hip arthroscopy. Biochemical analysis was undertaken in 21 flaps from 20 patients, and cellular viability was determined in 10 flaps from 10 patients. Biochemical analysis included concentrations of (1) DNA (an indicator of chondrocyte content), (2) hydroxyproline (an indicator of collagen content), and (3) glycosaminoglycan (an indicator of chondrocyte biosynthesis). Higher values for these parameters indicated more healthy tissue. The flaps were examined to determine the percentage of viable chondrocytes.The percentage of acetabular chondral flap specimens that had concentrations within 1 SD of the mean values reported in previous normal cartilage studies was 38% for DNA, 0% for glycosaminoglycan, and 43% for hydroxyproline. The average cellular viability of our acetabular chondral flap specimens was 39% (SD, 14%). Only 2 of the 10 specimens had more than half the cells still viable. There was no correlation between (1) the gross examination of the joint or knowledge of the patient's demographic characteristics and symptoms and (2) biochemical properties and cell viability of the flap, with one exception: a degenerative appearance of the surrounding cartilage correlated with a higher hydroxyproline concentration.Although full-thickness acetabular chondral flaps can appear normal grossly, the biochemical properties and percentage of live chondrocytes in full-thickness chondral flaps encountered in hip arthroscopy show that this tissue is not normal.There has been recent interest in repairing chondral flaps encountered during hip arthroscopy. These data suggest that acetabular chondral flaps are not biochemically and cellularly normal. Although these flaps may still be valuable mechanically and/or as a scaffold in some conductive or inductive capacity, further study is required to assess the clinical benefit of repair.

View details for DOI 10.1016/j.arthro.2015.01.010

View details for Web of Science ID 000355636500012

View details for PubMedID 25749531

Femoral Neck Stress Fractures and Imaging Features of Femoroacetabular Impingement PM&R Goldin, M., Anderson, C. N., Fredericson, M., Safran, M. R., Stevens, K. J. 2015; 7 (6): 584-592


Prior literature has suggested an association between the radiographic signs of femoroacetabular impingement (FAI) and femoral neck stress fractures (FNSF) or femoral neck stress reactions (FNSR). At the time of the writing of this article, no study has described the association of FAI and FNSF/FNSR along with the need for surgical intervention and outcomes.To determine the prevalence of radiographic features of FAI in patients diagnosed with FNSF.Retrospective case series.Tertiary care, institutional setting.A medical records search program (Stanford Translational Research Integrated Database Environment, Stanford University, California) was used to retrospectively search for patients 18-40 years old with a history of FNSF or FNSR. The records were obtained from the period July 25, 2003, to September 23, 2011.For assessment of risk factors, plain radiographs and magnetic resonance imaging studies were reviewed for features of cam or pincer FAI. Medical records were reviewed to determine whether patients required operative intervention.Incidence of abnormal alpha (α) angle, abnormal anterior offset ratio, abnormal femoral head-neck junction, coxa profunda, positive crossover sign, and abnormal lateral center-to-edge angle.Twenty-one female and 3 male participants (mean age 27 years, range 19-39 years) were identified with magnetic resonance imaging evidence of femoral neck stress injury. Cam morphology was seen in 10 patients (42%). Pincer morphology could be assessed in 18 patients, with coxa profunda in 14 (78%) and acetabular retroversion in 6 (14%). Features of combined pincer and cam impingement were observed in 4 patients (17%). Seven patients (29%) had operative intervention, with 3 (12%) requiring internal fixation of their femoral neck fractures, and all had radiographic evidence of fracture union after surgery. Four patients (17%) had persistent symptoms after healing of their FNSF with conservative treatment and eventually required surgery for FAI, 3 had no pain at final follow-up 1 year post-surgery, and one patient was lost to follow-up.The results of the current study suggest that patients in the general population with femoral neck stress injuries have a higher incidence of bony abnormalities associated with pincer impingement, including coxa profunda and acetabular retroversion, although it is unclear whether pincer FAI is a true risk factor in the development of FNSF.

View details for DOI 10.1016/j.pmrj.2014.12.008

View details for Web of Science ID 000356053400005

View details for PubMedID 25591871

RESTORATION OF THE SEAL FUNCTION OF THE ACETABULAR LABRUM: IN VITRO STUDY JOURNAL OF MECHANICS IN MEDICINE AND BIOLOGY Signorelli, C., Lopomo, N., Colle, F., Bontempi, M., Visani, A., Zaffagnini, S., Marcacci, M., Safran, M. R. 2015; 15 (2)
Hip Range of Motion and Association With Injury in Female Professional Tennis Players AMERICAN JOURNAL OF SPORTS MEDICINE Young, S. W., Dakic, J., Stroia, K., Nguyen, M. L., Harris, A. H., Safran, M. R. 2014; 42 (11): 2654-2658


Adequate hip range of motion is required for the transfer of energy from the lower to the upper extremity along the kinetic chain. Repetitive rotational stresses in the lower extremities during tennis may lead to sport-specific range of motion adaptations, which may increase the risk of injury to other joints along the kinetic chain.To assess whether such range of motion adaptations occur in the hip, and if so, to identify whether they are associated with injury.Cross-sectional study; Level of evidence, 3.A total of 125 female professional tennis players, the majority of whom were ranked in the top 200 World Tennis Association singles rankings, underwent a comprehensive preparticipation physical health status examination. Hip range of motion was assessed using a digital inclinometer and side-to-side differences in rotational parameters calculated, and associations with previous injuries were identified.A history of an abdominal strain was reported by 10% of players, and there was an association between abdominal strains and the presence of hip flexion contractures (odds ratio, 6.1; P = .006). Hip flexion contractures were bilateral in 85% of those found, affected only the nondominant side in 9%, and affected only the dominant side in 6%. We were unable to identify any specific side-to-side rotational adaptations in the dominant or nondominant hips, and no association between loss of hip range of motion and shoulder, lower back, hip, knee, or ankle injuries was found.We report an association in female professional tennis players between abdominal strains and flexion contractures of the hip with iliopsoas tightness. We did not find evidence of specific hip adaptations in rotational range of motion. If hip flexion contractures are found on clinical examination, a stretching program may be indicated. Further studies are required to assess whether such a program can reduce the risk of abdominal injury.

View details for DOI 10.1177/0363546514548852

View details for Web of Science ID 000344658000018

View details for PubMedID 25214532

A quantitative assessment of the insertional footprints of the hip joint capsular ligaments and their spanning fibers for reconstruction CLINICAL ANATOMY Telleria, J. J., Lindsey, D. P., Giori, N. J., Safran, M. R. 2014; 27 (3): 489-497


Quantitative descriptions of the hip joint capsular ligament insertional footprints have been reported. Using a three-dimensional digitizing system, and computer modeling, the area, and dimensions of the three main hip capsular ligaments and their insertional footprints were quantified in eight cadaveric hips. The iliofemoral ligament (ILFL) attaches proximally to the anterolateral supra-acetabular region (mean area = 4.2 cm(2)). The mean areas of the ILFL lateral and medial arm insertional footprints are 4.8 and 3.1 cm(2), respectively. The pubofemoral ligament (proximal footprint mean area = 1.4 cm(2)) blends with the medial ILFL anteriorly and the proximal ischiofemoral ligament (ISFL) distally without a distal bony insertion. The proximal and distal ISFL footprint mean areas are 6.4 and 1.2 cm(2), respectively. The hip joint capsular ligaments have consistent anatomic and insertional patterns. Quantification of the ligaments and their attachment sites may aid in improving anatomic repairs and reconstructions of the hip joint capsule using open and/or arthroscopic techniques.

View details for DOI 10.1002/ca.22272

View details for Web of Science ID 000332794400033

View details for PubMedID 24293171

Ischiofemoral impingement of the hip: a novel approach to treatment KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY Safran, M., Ryu, J. 2014; 22 (4): 781-785


Ischiofemoral impingement (IFI) is an uncommon source of hip pain recently described in the non-surgical hip, associated with decreased space between the lesser trochanter and the ischium. There are no reports in the English literature of surgical treatment of this problem. We describe a case of IFI in a 19-year-old female who failed conservative management and underwent endoscopic surgical intervention to increase the space between her ischium and proximal femur. More than 2 years later, the patient is doing very well with an improvement of her iHOT score of 53 points to 85.

View details for DOI 10.1007/s00167-013-2801-8

View details for Web of Science ID 000333157000012

View details for PubMedID 24346740

Biomechanical analysis of three tennis serve types using a markerless system. British journal of sports medicine Abrams, G. D., Harris, A. H., Andriacchi, T. P., Safran, M. R. 2014; 48 (4): 339-342


PURPOSE: The tennis serve is commonly associated with musculoskeletal injury. Advanced players are able to hit multiple serve types with different types of spin. No investigation has characterised the kinematics of all three serve types for the upper extremity and back. METHODS: Seven NCAA Division I male tennis players performed three successful flat, kick and slice serves. Serves were recorded using an eight camera markerless motion capture system. Laser scanning was utilised to accurately collect body dimensions and data were computed using inverse kinematic methods. RESULTS: There was no significant difference in maximum back extension angle for the flat, kick or slice serves. The kick serve had a higher force magnitude at the back than the flat and slice as well as larger posteriorly directed shoulder forces. The flat serve had significantly greater maximum shoulder internal rotation velocity versus the slice serve. Force and torque magnitudes at the elbow and wrist were not significantly different between the serves. CONCLUSIONS: The kick serve places higher physical demands on the back and shoulder while the slice serve demonstrated lower overall kinetic forces. This information may have injury prevention and rehabilitation implications.

View details for DOI 10.1136/bjsports-2012-091371

View details for PubMedID 22936411

Arthroscopic Management of Protrusio Acetabuli ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY Safran, M. R., Epstein, N. P. 2013; 29 (11): 1777-1782


The purpose of this study was to evaluate 4 hips with symptomatic protrusio acetabuli treated arthroscopically for symptomatic pincer-type femoroacetabular impingement in 3 patients aged younger than 40 years.Four hips in 3 patients, all active women, aged 26 to 37 years, with hip pain and radiographic evidence of protrusio acetabuli and a center-edge angle (CEA) of 50° or more, were studied and followed up for a minimum of 2.5 years. Each of these patients underwent arthroscopic anterior and lateral acetabuloplasty, partial labrectomy, synovectomy, and chondroplasty. Follow-up included evaluation with the modified Harris Hip Score (mHHS), radiographs, and clinical history and examination.Patient 1 had bilateral hip surgeries. The right hip was followed up for 63 months, and the CEA improved from 67° to 60°, with an mHHS score improvement by 60.4 points. The CEA for the left hip improved from 63° to 53° at 61 months' follow-up, and the mHHS improved by 43.9 points. Both hips had a final mHHS of 100 points. Patient 3, followed up for 28 months, had a final mHHS of 100 points, 32 points better than preoperatively, whereas the CEA improved from 51° to 44°. Patient 3, a 26-year-old with preoperative radiographically apparent arthritis, had a final mHHS of 87 points, 35 points better than preoperatively, and the CEA improved from 50° to 42° at 32 months' follow-up. All 3 patients were happy with their outcomes.In this small case series, arthroscopic acetabuloplasty showed reduced symptoms and improved function in 3 patients with protrusio aged younger than 40 years at a minimum of 2.5 years' follow-up.Level IV, therapeutic case series.

View details for DOI 10.1016/j.arthro.2013.08.003

View details for Web of Science ID 000326133700013

View details for PubMedID 24209674

ACL Reconstruction in Patients Aged 40 Years and Older A Systematic Review and Introduction of a New Methodology Score for ACL Studies AMERICAN JOURNAL OF SPORTS MEDICINE Brown, C. A., McAdams, T. R., Harris, A. H., Maffulli, N., Safran, M. R. 2013; 41 (9): 2181-2190


Treatment of the anterior cruciate ligament (ACL)-deficient knee in older patients remains a core debate.To perform a systematic review of studies that assessed outcomes in patients aged 40 years and older treated with ACL reconstruction and to provide a new methodological scoring system that is directed at critical assessment of studies evaluating ACL surgical outcomes: the ACL Methodology Score (AMS).Systematic review.A comprehensive literature search was performed from 1995 to 2012 using MEDLINE, EMBASE, and Scopus. Inclusion criteria for studies were primary ACL injury, patient age of 40 years and older, and mean follow-up of at least 21 months after reconstruction. Nineteen studies met the inclusion criteria from the 371 abstracts from MEDLINE and 880 abstracts from Scopus. Clinical outcomes (International Knee Documentation Committee [IKDC], Lysholm, and Tegner activity scores), joint stability measures (Lachman test, pivot-shift test, and instrumented knee arthrometer assessment), graft type, complications, and reported chondral or meniscal injury were evaluated in this review. A new methodology scoring system was developed to be specific at critically analyzing ACL outcome studies and used to examine each study design.Nineteen studies describing 627 patients (632 knees; mean age, 49.0 years; range, 42.6-60.0 years) were included in the review. The mean time to surgery was 32.0 months (range, 2.9-88.0 months), with a mean follow-up of 40.2 months (range, 21.0-114.0 months). The IKDC, Lysholm, and Tegner scores and knee laxity assessment indicated favorable results in the studies that reported these outcomes. Patients did not demonstrate a significant difference between graft types and functional outcome scores or stability assessment. The mean AMS was 43.9 ± 7.2 (range, 33.5-57.5). The level of evidence rating did not positively correlate with the AMS, which suggests that the new AMS system may be able to detect errors in methodology or reporting that may not be taken into account by the classic level of evidence rating.Patients aged 40 years and older with an ACL injury can have satisfactory outcomes after reconstruction. However, the quality of currently available data is still limited, such that further well-designed studies are needed to determine long-term efficacy and to better inform our patients with regard to expected outcomes.

View details for DOI 10.1177/0363546513481947

View details for Web of Science ID 000325714200028

View details for PubMedID 23548805

Applications of computer navigation in sports medicine knee surgery: an evidence-based review. Current reviews in musculoskeletal medicine Young, S. W., Safran, M. R., Clatworthy, M. 2013; 6 (2): 150-157


Computer-assisted surgery (CAS) has been investigated in a number of sports medicine procedures in the knee. Current barriers to its widespread introduction include increased costs, duration, and invasiveness of surgery. Randomized trials on the use of CAS in anterior cruciate ligament reconstruction have failed to demonstrate a clinical benefit. Data on CAS use in high tibial osteotomy are more promising; however, long-term studies are lacking. CAS has a number of research applications in knee ligament surgery, and studies continue to explore its use in the treatment of osteochondral lesions. This article reviews the applications of CAS in sports medicine knee surgery and summarizes current literature on clinical outcomes.

View details for DOI 10.1007/s12178-013-9166-y

View details for PubMedID 23483407

Risk of sciatic nerve traction injury during hip arthroscopy—is it the amount or duration? An intraoperative nerve monitoring study. journal of bone and joint surgery. American volume Telleria, J. J., Safran, M. R., Harris, A. H., Gardi, J. N., Glick, J. M. 2012; 94 (22): 2025-2032


Using intraoperative nerve monitoring we prospectively studied the prevalence, pattern, and predisposing factors for sciatic nerve traction injury during hip arthroscopy.The transcranial motor (tcMEP) and/or somatosensory (SSEP) evoked potentials of seventy-six patients undergoing hip arthroscopy in the lateral position were recorded. Changes in the posterior tibial and common peroneal nerves were evaluated to assess the effects of the amount and duration of traction on nerve function. Sixteen subjects were excluded because of incomplete data. Nerve dysfunction was defined as a 50% reduction in the amplitude of SSEPs or tcMEPs or a 10% increase in the latency of the SSEPs; nerve injury was defined as a clinically apparent sensory or motor deficit. Traction time and weight were continuously monitored with use of a custom foot-plate tensiometer.Of sixty patients (thirty-one female and twenty-nine male, with a mean age of thirty-seven years [range, sixteen to sixty-one years]), thirty-five (58%) had intraoperative nerve dysfunction and four (7%) sustained a clinical nerve injury. The average maximum traction weight (and standard deviation) for patients who did and those who did not have nerve dysfunction or injury was 38.1 ± 7.8 kg (range, 22.7 to 56.7 kg) and 32.9 ± 7.9 kg (range, 22.7 to 45.4 kg), respectively. The odds of a nerve event increased 4% with every 0.45-kg (1-lb) increase in the traction amount (age/sex-adjusted; p=0.043; odds ratio, 1.04; 95% confidence interval, 1.01 to 1.08). The average total traction time for patients who did and those who did not have nerve dysfunction was 95.9 ± 41.9 minutes (range, forty-two to 240 minutes) and 82.3 ± 35.4 minutes (range, thirty-eight to 160 minutes), respectively, and an increase in traction time did not increase the odds of a nerve event (p = 0.201). Age and sex were not significant risk factors.The prevalence of nerve changes seen with monitoring of SSEPs and tcMEPs is greater than what is clinically identified. The maximum traction weight, not the total traction time, is the greatest risk factor for sciatic nerve dysfunction during hip arthroscopy. This study did not identify a discrete threshold of traction weight or traction time that increased the odds of nerve dysfunction.

View details for PubMedID 23052834

Arthroscopic Rotator Cuff Repair-Traditional Anchor Techniques OPERATIVE TECHNIQUES IN SPORTS MEDICINE Cheung, E. V., Safran, M. R. 2012; 20 (3): 213-219
Kinematics Differences Between the Flat, Kick, and Slice Serves Measured Using a Markerless Motion Capture Method ANNALS OF BIOMEDICAL ENGINEERING Sheets, A. L., Abrams, G. D., Corazza, S., Safran, M. R., Andriacchi, T. P. 2011; 39 (12): 3011-3020


Tennis injuries have been associated with serving mechanics, but quantitative kinematic measurements in realistic environments are limited by current motion capture technologies. This study tested for kinematic differences at the lower back, shoulder, elbow, wrist, and racquet between the flat, kick, and slice serves using a markerless motion capture (MMC) system. Seven male NCAA Division 1 players were tested on an outdoor court in daylight conditions. Peak racquet and joint center speeds occurred sequentially and increased from proximal (back) to distal (racquet). Racquet speeds at ball impact were not significantly different between serve types. However, there were significant differences in the direction of the racquet velocity vector between serves: the kick serve had the largest lateral and smallest forward racquet velocity components, while the flat serve had the smallest vertical component (p < 0.01). The slice serve had lateral velocity, like the kick, and large forward velocity, like the flat. Additionally, the racquet in the kick serve was positioned 8.7 cm more posterior and 21.1 cm more medial than the shoulder compared with the flat, which could suggest an increased risk of shoulder and back injury associated with the kick serve. This study demonstrated the potential for MMC for testing sports performance under natural conditions.

View details for DOI 10.1007/s10439-011-0418-y

View details for Web of Science ID 000296507000014

View details for PubMedID 21984513

Diagnosis and Management of Ulnar Collateral Ligament Injuries in Throwers CURRENT SPORTS MEDICINE REPORTS Freehill, M. T., Safran, M. R. 2011; 10 (5): 271-278


Although ulnar collateral ligament (UCL) injuries are reported most commonly in baseball players (especially in pitchers), these also have been observed in other throwing sports including water polo, javelin throw, tennis, and volleyball. This article reviews the functional anatomy and biomechanics of the UCL with associated pathophysiology of UCL injuries of the elbow of the athlete participating in overhead throwing. Evaluation, including pertinent principles in history, physical examination, and imaging modalities, is discussed, along with the management options.

View details for DOI 10.1249/JSR.0b013e31822d4000

View details for Web of Science ID 000294685000005

View details for PubMedID 23531973

Musculoskeletal injuries in the tennis player MINERVA ORTOPEDICA E TRAUMATOLOGICA Abrams, G. D., Safran, M. R. 2011; 62 (4): 311-329
Femoroacetabular Impingement Patients Exhibit Hip Flexion Angle Abnormalities During Level Walking 57th Annual Meeting of the American-College-of-Sports-Medicine / Inaugural World Congress on Exercise is Medicine Shu, B., Rylander, J. H., Andriacchi, T. P., Safran, M. R. LIPPINCOTT WILLIAMS & WILKINS. 2010: 21–21
Evaluation of formal methods in hip joint center assessment: An in vitro analysis CLINICAL BIOMECHANICS Lopomo, N., Sun, L., Zaffagnini, S., Giordano, G., Safran, M. R. 2010; 25 (3): 206-212


The hip joint center is a fundamental landmark in the identification of lower limb mechanical axis; errors in its location lead to substantial inaccuracies both in joint reconstruction and in gait analysis. Actually in Computer Aided Surgery functional non-invasive procedures have been tested in identifying this landmark, but an anatomical validation is scarcely discussed.A navigation system was used to acquire data on eight cadaveric hips. Pivoting functional maneuver and hip joint anatomy were analyzed. Two functional methods - both with and without using the pelvic tracker - were evaluated: specifically a sphere fit method and a transformation techniques. The positions of the estimated centers with respect to the anatomical center of the femoral head, the influence of this deviation on the kinematic assessment and on the identification of femoral mechanical axis were analyzed.We found that the implemented transformation technique was the most reliable estimation of hip joint center, introducing a - Mean (SD) - difference of 1.6 (2.7) mm from the anatomical center with the pelvic tracker, whereas sphere fit method without it demonstrated the lowest accuracy with 25.2 (18.9) mm of deviation. Otherwise both the methods reported similar accuracy (<3mm of deviation).The functional estimations resulted in the best case to be in an average of less than 2mm from the anatomical center, which corresponds to angular deviations of the femoral mechanical axis smaller than 1.7 (1.3) degrees and negligible errors in kinematic assessment of angular displacements.

View details for DOI 10.1016/j.clinbiomech.2009.11.008

View details for Web of Science ID 000275986300004

View details for PubMedID 20006913

Case Reports: Unusual Cause of Shoulder Pain in a Collegiate Baseball Player CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Ligh, C. A., Schulman, B. L., Safran, M. R. 2009; 467 (10): 2744-2748


The objective of reporting this case was to introduce a unique cause of shoulder pain in a high-level Division I NCAA collegiate baseball player. Various neurovascular causes of shoulder pain have been described in the overhead athlete, including quadrilateral space syndrome, thoracic outlet syndrome, effort thrombosis, and suprascapular nerve entrapment. All of these syndromes are uncommon and frequently are missed as a result of their rarity and the need for specialized tests to confirm the diagnosis. This pitcher presented with nonspecific posterior shoulder pain that was so severe he could not throw more than 50 feet. Eventually, intermittent axillary artery compression with the arm in abduction resulting from hypertrophy of the pectoralis minor and scalene muscles was documented by performing arteriography with the arm in 120 degrees abduction. MRI-MR angiographic evaluation revealed no anatomic abnormalities. The patient was treated successfully with a nonoperative rehabilitation program and after 6 months was able to successfully compete at the same level without pain.

View details for DOI 10.1007/s11999-009-0962-z

View details for Web of Science ID 000269926400036

View details for PubMedID 19588212

The role of the elbow musculature, forearm rotation, and elbow flexion in elbow stability: An in vitro study JOURNAL OF SHOULDER AND ELBOW SURGERY Seiber, K., Gupta, R., McGarry, M. H., Safran, M. R., Lee, T. Q. 2009; 18 (2): 260-268


The goal of this study was to define the relative passive contributions of the major muscle groups about the elbow to varus-valgus stability and to determine whether these contributions vary with forearm rotation and elbow flexion. Fourteen cadaveric upper extremities were tested with a custom elbow testing device. The biceps, brachialis, and triceps muscles were loaded to simulate passive tension. The origins and insertions of the remaining muscles that cross the elbow were left intact to assess the contributions of their passive tension to elbow stability. For each specimen, varus-valgus laxity was measured at 30 degrees , 50 degrees , and 70 degrees of elbow flexion with the forearm in full supination, pronation, and neutral rotation, yielding 9 total positions of assessment. Six specimens (series 1) were tested for varus-valgus laxity after the following sequence of conditions: (1) unloaded biceps, brachialis, and triceps; (2) loaded biceps, brachialis, and triceps; (3) release of lateral elbow muscle tension; (4) release of medial elbow muscle tension; and (5) transection of the anterior bundle of the ulnar collateral ligament (UCL). Eight specimens (series 2) were assessed under the same conditions, only with the order of the last 2 conditions reversed for further comparison. Release of the lateral muscles alone increased varus-valgus laxity by a mean of 0.6 degrees to 1.4 degrees , but this was statistically significant only at positions of forearm pronation in series 1 (P < .012) and only at 2 of 9 positions in series 2 (30 degrees of flexion in pronation and 50 degrees of flexion in neutral rotation, P < .049). Release of the medial muscles alone caused a further increase in varus-valgus laxity by a mean of 0.5 degrees to 1.2 degrees , but this was only statistically significant at 30 degrees , 50 degrees , and 70 degrees of flexion in supination (P < .014) and 70 degrees of flexion in pronation (P = .044) in series 1 and only at 30 degrees , 50 degrees , and 70 degrees of flexion in supination in series 2 (P < .046). Release of the anterior bundle of the UCL resulted in a statistically significant increase in elbow varus-valgus laxity at all elbow and forearm positions by a mean of 1.8 degrees to 3.2 degrees (P < .001). Unloading the biceps, triceps, and brachialis caused significant increases in varus-valgus laxity at most elbow testing positions, independent of the position of forearm rotation (P < .046). Thus, the medial elbow musculature and lateral elbow musculature affect total elbow varus-valgus stability to roughly equal magnitudes, and the anterior bundle of the UCL affects stability to over twice the magnitude of either muscle group. The medial elbow musculature mostly affects elbow stability with the arm in supination and the lateral musculature in pronation, where the passive tension in the respective muscles is increased. Furthermore, the medial elbow musculature provided stability to the elbow when the forearm was supinated even with a deficient anterior bundle of the UCL, emphasizing its role as a secondary stabilizer.

View details for DOI 10.1016/j.jse.2008.08.004

View details for Web of Science ID 000263692600018

View details for PubMedID 19046641

Elbow valgus laxity may result in an overestimation of apparent shoulder external rotation during physical examination AMERICAN JOURNAL OF SPORTS MEDICINE Mihata, T., Safran, M. R., McGarry, M. H., Abe, M., Lee, T. Q. 2008; 36 (5): 978-982


The contributions of the scapulothoracic articulation and spine when measuring shoulder range of motion have been well described; however, the effect of elbow valgus laxity has not.Increased elbow valgus laxity affects the assessment of shoulder external rotation measured during physical examination at 90 degrees of elbow flexion.Controlled laboratory study.Seven cadaveric upper extremities were tested with an elbow valgus laxity-testing device. Shoulder external rotation was assessed with 2.8 N . m of external torque by measuring a change in the angle of the forearm axis at 90 degrees of elbow flexion. Elbow valgus laxity was measured in degrees of valgus angulation with 1.5 N . m of valgus torque with the humerus fixed. Shoulder external rotation and elbow valgus laxity were recorded at each of the following conditions: (1) intact, (2) after splitting the pronator muscles and venting the capsule, (3) after cutting the posterior band of the anterior oblique ligament of the ulnar collateral ligament, and (4) after cutting the anterior oblique ligament completely.After the posterior band of the anterior oblique ligament of the ulnar collateral ligament was cut, apparent shoulder external rotation and elbow valgus laxity were increased by 4.1 degrees +/- 1.7 degrees (P < .01) and 3.1 degrees +/- 1.3 degrees (P < .001), respectively, when compared with the intact condition. Complete cutting of the anterior oblique ligament resulted in an apparent increased shoulder external rotation and an increased elbow valgus laxity of 11.0 degrees +/- 1.1 degrees (P < .001) and 9.1 degrees +/- 1.2 degrees (P < .001), respectively, when compared with the intact condition.Shoulder external rotation as assessed by physical examination, which was defined as the angle of the forearm axis, as well as elbow valgus laxity, was significantly increased after the anterior oblique ligament of the ulnar collateral ligament was cut, although the glenohumeral joint condition was not changed.Elbow valgus laxity may cause an overestimation of shoulder external rotation on clinical examination of the shoulder.

View details for DOI 10.1177/0363546507313086

View details for Web of Science ID 000255752900022

View details for PubMedID 18272796

Interobserver agreement in the classification of rotator cuff tears using magnetic resonance imaging AMERICAN JOURNAL OF SPORTS MEDICINE Spencer, E. E., Dunn, W. R., Wright, R. W., Wolf, B. R., Spindler, K. P., McCarty, E., Ma, C. B., Jones, G., Safran, M., Holloway, B., Kuhn, J. E. 2008; 36 (1): 99-103


Although magnetic resonance imaging (MRI) is a standard method of assessing the extent and features of rotator cuff disease, the authors are not aware of any studies that have assessed the interobserver agreement among orthopaedic surgeons reviewing MRI scans for rotator cuff disease.Fellowship-trained orthopaedic shoulder surgeons will have good interobserver agreement in predicting the more salient features of rotator cuff disease such as tear type (full thickness versus partial thickness), tear size, and number of tendons involved but only fair agreement with more complex features such as muscle volume, fat content, and the grade of partial-thickness cuff tears.Cohort study (diagnosis); Level of evidence, 3.Ten fellowship-trained orthopaedic surgery shoulder specialists reviewed 27 MRI scans of 27 shoulders from patients with surgically confirmed rotator cuff disease. The ability to interpret full-thickness versus partial-thickness tears, acromion type, acromioclavicular joint spurs or signal changes, biceps lesions, size and grade of partial-thickness tears, acromiohumeral distance, number of tendons involved and amount of retraction for full-thickness tears, size of full-thickness tears, and individual muscle fatty infiltration and atrophy were assessed. Surgeons completed a standard evaluation form for each MRI scan. Interobserver agreement was determined and a kappa level was derived.Interobserver agreement was highest (>80%) for predicting full- versus partial-thickness tears of the rotator cuff, and for quantity of the teres minor tendon. Agreement was slightly less (>70%) for detecting signal in the acromioclavicular joint, the side of the partial-thickness tear, the number of tendons involved in a full-thickness tear, and the quantity of the subscapularis and infraspinatus muscle bellies. Agreement was less yet (60%) for detecting the presence of spurs at the acromioclavicular joint, a tear of the long head of the biceps tendon, amount of retraction of a full-thickness tear, and the quantity of the supraspinatus. The best kappa statistics were found for detecting the difference between a full- and partial-thickness rotator cuff tear (0.77), and for the number of tendons involved for full-thickness tears (0.55). Kappa for predicting the involved side of a partial-thickness tear was 0.44; for predicting the grade of a partial-thickness tear, it was -0.11.Fellowship-trained, experienced orthopaedic surgeons had good agreement for predicting full-thickness rotator cuff tears and the number of tendons involved and moderate agreement in predicting the involved side of a partial-thickness rotator cuff tear, but poor agreement in predicting the grade of a partial-thickness tear.

View details for DOI 10.1177/0363546507307504

View details for Web of Science ID 000251875900011

View details for PubMedID 17932406

Surgical treatment of lateral epicondylitis: A systematic review CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Lo, M. Y., Safran, M. R. 2007: 98-106


For the minority of people with lateral epicondylitis who do not respond to nonoperative treatment, surgical intervention is an option, but confusion exists because of the plethora of options. The surgical techniques for treating lateral epicondylitis can be grouped into three main categories: open, percutaneous, and arthroscopic. Our primary question was whether there was clear evidence suggesting one of these three approaches was superior in relieving pain, restoring strength, or reducing time to return to work. A 2002 Cochrane Collaboration Database review found no conclusions could be drawn regarding the efficacy of operative treatment given the lack of controlled trials. Although there is not enough literature to conduct a meta-analysis, we systematically reviewed the available literature to address our questions. Although there are advantages and disadvantages to each procedure, no technique appears superior by any measure. Therefore, until more randomized, controlled trials are done, it is reasonable to defer to individual surgeons regarding experience and ease of procedure.

View details for DOI 10.1097/BLO.0b013e3181483dc4

View details for Web of Science ID 000250100300017

View details for PubMedID 17632419

The role of arthroscopy in the treatment of glenohumeral arthritis SPORTS MEDICINE AND ARTHROSCOPY REVIEW Safran, M. R., Baillargeon, D. 2004; 12 (2): 139-145
Effects of injury and reconstruction of the posterior cruciate ligament on proprioception and neuromuscular control Workshop on the Role of Proprioception and Neuromuscular Control in the Management and Rehabilitation of Joint Pathology Safran, M. R., Harner, C. D., Giraldo, J. L., Fu, F. H., Lephart, S. M. HUMAN KINETICS PUBL. 2000: 225–235
Fibronectin-aggrecan complex as a marker for cartilage degradation in non-arthritic hips. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA Abrams, G. D., Safran, M. R., Shapiro, L. M., Maloney, W. J., Goodman, S. B., Huddleston, J. I., Bellino, M. J., Scuderi, G. J. 2014; 22 (4): 768-773


To report hip synovial fluid cytokine concentrations in hips with and without radiographic arthritis.Patients with no arthritis (Tonnis grade 0) and patients with Tonnis grade 2 or greater hip osteoarthritis (OA) were identified from patients undergoing either hip arthroscopy or arthroplasty. Synovial fluid was collected at the time of portal establishment for those undergoing hip arthroscopy and prior to arthrotomy for the arthroplasty group. Analytes included fibronectin-aggrecan complex (FAC) as well as a standard 12 cytokine array. Variables recorded were Tonnis grade, centre-edge angle of Wiberg, as well as labrum and cartilage pathology for the hip arthroscopy cohort. A priori power analysis was conducted, and a Mann-Whitney U test and regression analyses were used with an alpha value of 0.05 set as significant.Thirty-four patients were included (17 arthroplasty, 17 arthroscopy). FAC was the only analyte to show a significant difference between those with and without OA (p < 0.001). FAC had significantly higher concentration in those without radiographic evidence of OA undergoing microfracture versus those not receiving microfracture (p < 0.05).There was a significantly higher FAC concentration in patients without radiographic OA. Additionally, those undergoing microfracture had increased levels of FAC. As FAC is a cartilage breakdown product, no significant amounts may be present in those with OA. In contrast, those undergoing microfracture have focal area(s) of cartilage breakdown. These data suggest that FAC may be useful in predicting cartilage pathology in those patients with hip pain but without radiographic evidence of arthritis.Diagnostic, Level III.

View details for DOI 10.1007/s00167-014-2863-2

View details for PubMedID 24477496

Hip arthroscopy: from the beginning to the future-an innovator's perspective KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY Glick, J. M., Valone, F., Safran, M. R. 2014; 22 (4): 714-721


Hip arthroscopy is one of the fastest-growing areas of orthopaedic surgery. There are many reasons for this, including a better understanding of the pathophysiology of damage to the hip joint, improvements in imaging and technology advancements in arthroscopic instrumentation. This manuscript documents the historical development of hip arthroscopy, in general, as well as advances and ideas that have led to common techniques with regard to portal placement, traction and instrumentation. These advances have led to expanding indications for hip arthroscopy. This manuscript ends with some thoughts about the future of hip arthroscopy from the perspective of one of the leaders who helped shape hip arthroscopy, as it is performed today.

View details for DOI 10.1007/s00167-014-2859-y

View details for Web of Science ID 000333157000002

View details for PubMedID 24482213

Functional testing provides unique insights into the pathomechanics of femoroacetabular impingement and an objective basis for evaluating treatment outcome JOURNAL OF ORTHOPAEDIC RESEARCH Rylander, J., Shu, B., Favre, J., Safran, M., Andriacchi, T. 2013; 31 (9): 1461-1468


Femoroacetabular impingement (FAI) has been recognized as a significant clinical problem. While hip reshaping surgery for treating FAI has had positive clinical outcomes, there remains a need for objective functional outcomes of FAI treatment. We tested the hypothesis that during walking and stair climbing significant changes in hip kinematics would occur following hip reshaping surgery that indicate restoration of normal function post-operatively. Hip and pelvic kinematics were collected for 17 FAI patients pre- and 1 year post-operatively and compared to 17 healthy matched controls. Prior to surgery, FAI patients had significantly reduced hip internal rotation and hip sagittal plane range of motion during walking (p = 0.01, p < 0.001, respectively) and stair climbing (p = 0.01, p < 0.001, respectively) as compared with controls. Post-operatively, these motions were restored to normal during walking (p = 0.70, p = 0.46, respectively), but remained significantly reduced in the FAI patients during stair climbing (p = 0.03, p < 0.001, respectively). These results have important implications for understanding the functional pathomechanics of FAI and providing an objective basis for evaluating treatment outcome. The stair climbing results indicate that problems still exist in the hip joint for activities requiring higher ranges of hip motion and suggest a basis for exploring future improvements for the treatment of FAI.

View details for DOI 10.1002/jor.22375

View details for Web of Science ID 000322005300017

View details for PubMedID 23625839

Spontaneous Hip Labrum Regrowth After Initial Surgical D,bridement CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Abrams, G. D., Safran, M. R., Sadri, H. 2013; 471 (8): 2504-2508


BACKGROUND: Anecdotal evidence from second-look hip arthroscopies and animal studies has suggested spontaneous labral regrowth may occur after débridement. However, these observations have not been systematically confirmed. QUESTIONS/PURPOSES: We (1) determined whether labral regrowth occurs after débridement in human hips; (2) if so, described the characteristics of the reconstituted labrum; and (3) determined the association, if any, of age with the presence and quality of labral regrowth. METHODS: We retrospectively reviewed all 24 patients who previously had open hip surgical dislocation with labral débridement for treatment of femoroacetabular impingement (FAI) and concomitant hip arthroscopy 2 years after index procedure in association with planned removal of trochanteric hardware between January and December 1999. Data recorded included amount of labral resection at the index procedure using the clockface method, presence and quality of any labral regrowth, presence of any labral scarring or inflammation, and WOMAC(®) scores. Minimum clinical followup was 11 years (average, 12 years; range, 11-12 years). RESULTS: All patients demonstrated labral regrowth at arthroscopy at 2 years. Homogeneous regrowth of labral height was seen in 21 of 24 patients, with labral scarring noted in four of 24. Average WOMAC(®) score was 98 points (range, 90-100 points) at the time of hardware removal. Increasing patient age was independently associated with decreased WOMAC(®) score and inhomogeneous regrowth of the labrum. CONCLUSIONS: Labral regrowth after resection was seen in all patients at 2 years from index operation. Increasing age, however, was associated with poorer quality of the reconstituted labrum. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

View details for DOI 10.1007/s11999-013-2914-x

View details for Web of Science ID 000321549600017

View details for PubMedID 23483380

Biomechanical evaluation of a coracoclavicular and acromioclacicular ligament reconstruction technique utilizing a single continuous intramedullary free tendon graft. Journal of shoulder and elbow surgery Abrams, G. D., McGarry, M. H., Jain, N. S., Freehill, M. T., Shin, S., Cheung, E. V., Lee, T. Q., Safran, M. R. 2013; 22 (7): 979-985


Reconstruction of only the coracoclavicular (CC) ligaments may restore superior-inferior (S-I) but not anterior-posterior (A-P) stability of the acromioclavicular (AC) joint. Concomitant reconstruction of both the AC and CC ligaments may more reliably restore intact biomechanical characteristics of the AC joint.Ten matched pairs of shoulders were utilized. Five specimens underwent CC ligament reconstruction while an equal number underwent combined AC and CC ligament reconstruction utilizing an intramedullary tendon graft. Each of the reconstructions was compared with the intact contralateral control. Translational and load to failure characteristics were compared between groups.No difference was found in S-I translation between intact specimens and CC-only reconstructions (P = .20) nor between intact specimens and AC/CC reconstructions (P = .33) at 10 Newton (N) loads. Significant differences were noted in A-P translation between intact specimens and CC-only reconstructions (P < .001) but no difference in A-P translation between intact specimens and AC/CC reconstructions (P = .34).The A-P and S-I translational biomechanical characteristics of the AC joint were restored using the new technique described. Reconstruction of the CC ligaments only (versus AC/CC combined) led to significantly increased translational motion in the A-P plane as compared to intact control specimens.

View details for DOI 10.1016/j.jse.2012.09.013

View details for PubMedID 23313367

Hip-femoral acetabular impingement. Clinics in sports medicine Anderson, C. N., Riley, G. M., Gold, G. E., Safran, M. R. 2013; 32 (3): 409-425

View details for DOI 10.1016/j.csm.2013.03.010

View details for PubMedID 23773875

In vitro analysis of peri-articular soft tissues passive constraining effect on hip kinematics and joint stability. Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA Safran, M. R., Lopomo, N., Zaffagnini, S., Signorelli, C., Vaughn, Z. D., Lindsey, D. P., Gold, G., Giordano, G., Marcacci, M. 2013; 21 (7): 1655-1663


PURPOSE: Aim of the study is to assess the contribution of peri-articular soft tissues to hip joint kinematics and their influence on hip stability. METHODS: Four hemi-corpse specimens (3 males, average age 72 years) were studied using a custom navigation system. Hip kinematics (femoral head motion relative to the acetabulum and joint range of motion) were evaluated with the hip manually positioned in 36 different positions with (I) soft tissues intact, (II) after removal of the skin and muscles and (III) after partial capsulectomy. Each position was repeated 3 times in each state. RESULTS: Excellent interclass correlation for each test was determined (ICC range, 0.84-0.96). Femoral head anatomical centre displacement relative to the acetabulum occurred in all 3 planes, even with all the soft tissue intact (average, 3.3 ± 2.8 mm lateral translation; 1.4 ± 1.8 mm posterior translation and 0.3 ± 1.5 mm distally). These translations increased as more soft tissue was removed, except medial-lateral displacement, with an average 4.6 ± 2.9 mm lateral translation, 0.7 ± 1.3 mm posterior translation and 1.5 ± 1.9 mm distal translation when partial capsulectomy was performed. Range of motion increased in all 3 planes with increasing removal of the soft tissues. CONCLUSIONS: This study showed that femoral head anatomical centre displacement within the acetabulum occurs and increases with increasing removal of peri-articular soft tissues, confirming their influence on hip stability. Hip kinematics was also influenced by peri-articular soft tissues; specifically range of motion increases with increasing removal of those tissues. From clinicians' point of view, they have therefore to consider the influence of their surgeries on peri-articular soft tissues, since excessive translations may promote hip arthritis.

View details for DOI 10.1007/s00167-012-2091-6

View details for PubMedID 22752414

Hip-femoral acetabular impingement. Clinics in sports medicine Anderson, C. N., Riley, G. M., Gold, G. E., Safran, M. R. 2013; 32 (3): 409-425


Magnetic resonance imaging (MRI) has become a valuable technology for the diagnosis and treatment of femoroacetabular impingement (FAI). This article reviews the basic pathophysiology of FAI, as well as the techniques and indications for MRI and magnetic resonance arthrography. Normal MRI anatomy of the hip and pathologic MRI anatomy associated with FAI are also discussed. Several case examples are presented demonstrating the diagnosis and treatment of FAI.

View details for DOI 10.1016/j.csm.2013.03.010

View details for PubMedID 23773875

MR Imaging of the Hip Pathologies and Morphologies of the Hip Joint, What the Surgeon Wants to Know MAGNETIC RESONANCE IMAGING CLINICS OF NORTH AMERICA Botser, I., Safran, M. R. 2013; 21 (1): 169-?


MR imaging of the hip is frequently used in symptomatic patients before hip preservation surgery; it is used as a decision-making tool and as a planning tool. The MRI can confirm the preliminary working diagnosis, identify other possible sources of pain, and highlight anatomic areas that are not routinely viewed during surgery. In addition, MR imaging is capable of illustrating normal and abnormal bony morphology of the femur and pelvis; and in the case that arthrography is used, diagnostic injection can be administrated concurrently. This article highlights a surgeon's perspective on the use of MR imaging in the patient with nonarthritic hip pain.

View details for DOI 10.1016/j.mric.2012.08.008

View details for Web of Science ID 000312619200014

View details for PubMedID 23168190

Relationship between femoroacetabular contact areas and hip position in the normal joint: an in vitro evaluation KNEE SURGERY SPORTS TRAUMATOLOGY ARTHROSCOPY Signorelli, C., Lopomo, N., Bonanzinga, T., Muccioli, G. M., Safran, M. R., Marcacci, M., Zaffagnini, S. 2013; 21 (2): 408-414
Epidemiology of musculoskeletal injury in the tennis player BRITISH JOURNAL OF SPORTS MEDICINE Abrams, G. D., Renstrom, P. A., Safran, M. R. 2012; 46 (7): 492-498


Tennis is a popular sport with tens of millions of players participating worldwide. This popularity was one factor leading to the reappearance of tennis as a medal sport at the 1988 Summer Olympics in Seoul, South Korea. The volume of play, combined with the physical demands of the sports, can lead to injuries of the musculoskeletal system. Overall, injury incidence and prevalence in tennis has been reported in a number of investigations. The sport creates specific demands on the musculoskeletal system, with acute injuries, such as ankle sprains, being more frequent in the lower extremity while chronic overuse injuries, such as lateral epicondylitis, are more common in the upper extremity in the recreational player and shoulder pain more common in the high-level player. This review discusses the epidemiology of injuries frequently experienced in tennis players and examines some of these injuries' correlation with the development of osteoarthritis. In addition, player-specific factors, such as age, sex, volume of play, skill level, racquet properties and grip positions as well as the effect of playing surface on the incidence and prevalence of injury is reported. Finally, recommendations on standardisation of future epidemiological studies on tennis injuries are made in order to be able to more easily compare results of future investigations.

View details for DOI 10.1136/bjsports-2012-091164

View details for Web of Science ID 000305280500010

View details for PubMedID 22554841

Articular cartilage friction increases in hip joints after the removal of acetabular labrum JOURNAL OF BIOMECHANICS Song, Y., Ito, H., Kourtis, L., Safran, M. R., Carter, D. R., Giori, N. J. 2012; 45 (3): 524-530


The acetabular labrum is believed to have a sealing function. However, a torn labrum may not effectively prevent joint fluid from escaping a compressed joint, resulting in impaired lubrication. We aimed to understand the role of the acetabular labrum in maintaining a low friction environment in the hip joint. We did this by measuring the resistance to rotation (RTR) of the hip, which reflects the friction of the articular cartilage surface, following focal and complete labrectomy. Five cadaveric hips without evidence of osteoarthritis and impingement were tested. We measured resistance to rotation of the hip joint during 0.5, 1, 2, and 3 times body weight (BW) cyclic loading in the intact hip, and after focal and complete labrectomy. Resistance to rotation, which reflects articular cartilage friction in an intact hip was significantly increased following focal labrectomy at 1-3 BW loading, and following complete labrectomy at all load levels. The acetabular labrum appears to maintain a low friction environment, possibly by sealing the joint from fluid exudation. Even focal labrectomy may result in increased joint friction, a condition that may be detrimental to articular cartilage and lead to osteoarthritis.

View details for DOI 10.1016/j.jbiomech.2011.11.044

View details for Web of Science ID 000300863600017

View details for PubMedID 22176711

MRI and arthroscopy correlations of the elbow: a case-based approach. Instructional course lectures Abrams, G. D., Stoller, D. W., Safran, M. R. 2012; 61: 235-249


The number of elbow arthroscopies and indications for the procedure have increased significantly since the advent of modern elbow arthroscopy in the 1980s. In addition to the patient history, physical examination, and plain radiography, MRI is an important tool for the clinician in diagnosing several pathologies within and around the elbow. Understanding the pathophysiology and clinical presentation and being familiar with the MRI characteristics of a variety of elbow conditions will assist the physician in making an accurate diagnosis and help guide appropriate treatment.

View details for PubMedID 22301236

MRI and arthroscopy correlations of the hip: a case-based approach. Instructional course lectures McCall, D. A., Safran, M. R. 2012; 61: 327-344


Disorders of the hip joint can be physically disabling for the patient and a diagnostic challenge for the physician. Advances in imaging the hip with MRI can help the physician determine a more specific diagnosis for patients with acute or chronic hip pain. MRI and particularly magnetic resonance arthrography have helped raised awareness of nonarthritic hip problems and have made the diagnosis of hip problems much easier. Intra-articular and extra-articular processes can be evaluated with MRI; multiple sequences are available to increase the sensitivity and specificity for detecting specific pathology around the hip. Because the hip is a deep joint within a large soft-tissue envelope, MRI more precisely delineates the sources of hip pain by evaluating the soft tissues and ligamentous structures around the hip. It is helpful to understand the role of MRI in evaluating common pathologic conditions within the hip joint, including labral tears, chondral lesions, loose bodies, tears of the ligamentum teres, femoral acetabular impingement, developmental dysplasia of the hip, and pigmented villonodular synovitis. Hip arthroscopy, a less invasive technique for treating hip problems, has also contributed to the rapid growth of interest in this area of orthopaedic surgery. Hip arthroscopy can be used to evaluate disorders in the intra-articular region (central and peripheral compartments) and periarticular region (iliopsoas bursa and tendon disorders) as well as those in the peritrochanteric region.

View details for PubMedID 22301244

Preoperative and Postoperative Sagittal Plane Hip Kinematics in Patients With Femoroacetabular Impingement During Level Walking AMERICAN JOURNAL OF SPORTS MEDICINE Rylander, J. H., Shu, B., Andriacchi, T. P., Safran, M. R. 2011; 39: 36S-42S


Femoroacetabular impingement (FAI) has been linked to osteoarthritis. Treatment options range from nonoperative to operative, and current outcome measures are generally subjective or not conducted under actual activities of daily living. Thus, there is a need for the use of motion capture techniques to quantitatively assess the outcome of surgical intervention for those treated for FAI.The gait of FAI patients 1 year after operative treatment (arthroscopic hip reshaping) will be significantly closer to the normal range and pattern of hip flexion motion, relative to pretreatment.Case series; Level of evidence, 4.Eleven patients between 18 and 44 years of age with diagnosed FAI were enrolled in this study. Kinematics and kinetics for this group of patients were collected using motion capture techniques before arthroscopic bone-reshaping surgery and again 1 year after surgery. Pain and perceived activity level (Tegner scale) were also collected. All collected data were compared using a paired t test.Overall hip sagittal plane range of motion increased on the affected side from 27.6° ± 5.0° to 30.7° ± 4.3° (P = .02). The presence of abnormal reversals (second-order change in the slope in the hip flexion/extension curve) that was present in 5 patients preoperatively disappeared or was reduced in prevalence and magnitude in 4 of the patients postoperatively. Additionally, pain decreased and activity level increased postoperatively.The results supported the hypothesis that surgical intervention for FAI restores more normal patterns of gait and provides objective support that the surgical procedure is useful. The results help establish motion capture as a potential method for quantitatively assessing the outcome in FAI surgical interventions. The presence of abnormal reversals in hip flexion has been reported in end-stage hip osteoarthritis, and the presence of these reversals in FAI patients reinforces the idea of FAI being a precursor to hip osteoarthritis.

View details for DOI 10.1177/0363546511413993

View details for Web of Science ID 000292167400006

View details for PubMedID 21709030

Strains Across the Acetabular Labrum During Hip Motion A Cadaveric Model AMERICAN JOURNAL OF SPORTS MEDICINE Safran, M. R., Giordano, G., Lindsey, D. P., Gold, G. E., Rosenberg, J., Zaffagnini, S., Giori, N. J. 2011; 39: 92S-102S


Labral tears commonly cause disabling intra-articular hip pain and are commonly treated with hip arthroscopy. However, the function and role of the labrum are still unclear.(1) Flexion, adduction, and internal rotation (a position clinically defined as the position for physical examination known as the impingement test) places greatest circumferential strain on the anterolateral labrum and posterior labrum; (2) extension with external rotation (a position clinically utilized during physical examination to assess for posterior impingement and for anterior instability) places significant circumferential strains on the anterior labrum; (3) abduction with external rotation during neutral flexion-extension (the position the extremity rests in when a patient lies supine) places the greatest load on the lateral labrum.Descriptive laboratory study. Methods: Twelve cadaveric hips (age, 79 years) without labral tears or arthritis were studied. Hips were dissected free of soft tissues, except the capsuloligamentous structures. Differential variable reluctance transducers were placed in the labrum anteriorly, anterolaterally, laterally, and posteriorly to record circumferential strains in all 4 regions as the hip was placed in 36 different positions.The posterior labrum had the greatest circumferential strains identified; the peak was in the flexed position, in adduction or neutral abduction-adduction. The greatest strains anteriorly were in flexion with adduction. The greatest strains anterolaterally were in full extension. External rotation had greater strains than neutral rotation and internal rotation. The greatest strains laterally were at 90° of flexion with abduction, and external or neutral rotation. In the impingement position, the anterolateral strain increased the most, while the posterior labrum showed decreased strain (greatest magnitude of strain change). When the hip is externally rotated and in neutral flexion-extension or fully extended, the posterior labrum has significantly increased strain, while the anterolateral labrum strain is decreased.These are the first comprehensive strain data (of circumferential strain) analyzing the whole hip labrum. For the intact labrum, the greatest strain change was at the posterior acetabulum, whereas clinically, acetabular labral tears occur most frequently anterolaterally or anteriorly. The results are consistent with the impingement test as an assessment of anterolateral acetabular labral stress. The hyperextension-rotation test, often used clinically to assess anterior hip instability and posterior impingement, did not show a change in strain anteriorly, but did reveal an increase in strain posteriorly.Although this study does not include muscular forces across the hip joint, it does provide a clue as to the stresses about the labrum through the complete range of motions of the hip, which may help in providing a better understanding of the cause of labral tears and in the protection of labral repairs.

View details for DOI 10.1177/0363546511414017

View details for Web of Science ID 000292167400014

View details for PubMedID 21709038

An Anatomic Arthroscopic Description of the Hip Capsular Ligaments for the Hip Arthroscopist ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY Telleria, J. J., Lindsey, D. P., Giori, N. J., Safran, M. R. 2011; 27 (5): 628-636


To examine and describe the normal anatomic intra-articular locations of the hip capsular ligaments in the central and peripheral compartments of the hip joint.Eight paired fresh-frozen human cadaveric hips (mean age, 73.3 years) were carefully dissected free of soft tissue to expose the hip capsule. Needles were placed through the capsule along the macroscopic borders of the hip capsular ligaments. Arthroscopy was performed on each hip, and the relations of the needles, and thus the ligaments, to the arthroscopic portals and other soft-tissue and osseous landmarks in the hip were recorded by use of a clock-face reference system.The iliofemoral ligament (ILFL) ran from 12:45 to 3 o'clock. The ILFL was pierced by the anterolateral and anterior portals just within its lateral and medial borders, respectively. The pubofemoral ligament was located from the 3:30 to the 5:30 clock position; the lateral border was at the psoas-U perimeter, and the medial border was at the junction of the anteroinferior acetabulum and the cotyloid fossa. The ischiofemoral ligament (ISFL) ran from the 7:45 to the 10:30 clock position. The posterolateral portal pierced the ISFL just inside its superior/lateral border, and the inferior/lateral border was located at the posteroinferior acetabulum. In the peripheral compartment the lateral ILFL and superior/lateral ISFL borders were in proximity to the lateral synovial fold. The medial ILFL and lateral pubofemoral ligament borders were closely approximated to the medial synovial fold.The hip capsular ligaments have distinct and consistent arthroscopic locations within the hip joint and are associated with clearly identifiable landmarks in the central and peripheral compartments. The standard hip arthroscopy portals are closely related to the borders of the hip capsular ligaments.These findings will help orthopaedic surgeons know which structures are being addressed during arthroscopic surgery and may help in the development of future hip procedures.

View details for DOI 10.1016/j.arthro.2011.01.007

View details for Web of Science ID 000289557700006

View details for PubMedID 21663720

The Labrum of the Hip: Diagnosis and Rationale for Surgical Correction CLINICS IN SPORTS MEDICINE Freehill, M. T., Safran, M. R. 2011; 30 (2): 293-?


The treatment of labral pathologic condition of the hip has become a topic of increasing interest. In patients undergoing hip arthroscopy, tears of the acetabular labrum are the most commonly found pathologic condition and most common cause of mechanical symptoms. Although a labral tear may occur with a single traumatic event, often another underlying cause may be already present, predisposing the individual to injury. This article discusses the structure and function of the acetabular labrum, the diagnosis of labral injury through physical examination and imaging modalities, and the current treatment options, including labrectomy, labral repair, and reconstruction.

View details for DOI 10.1016/j.csm.2010.12.002

View details for Web of Science ID 000289811500007

View details for PubMedID 21419957

Hip Instability: Anatomic and Clinical Considerations of Traumatic and Atraumatic Instability CLINICS IN SPORTS MEDICINE Shu, B., Safran, M. R. 2011; 30 (2): 349-?


Hip instability is uncommon because of the substantial conformity of the osseous femoral head and acetabulum. It can be defined as extraphysiologic hip motion that causes pain with or without the symptom of hip joint unsteadiness. The cause can be traumatic or atraumatic, and is related to both bony and soft tissue abnormality. Gross instability caused by trauma or iatrogenic injury has been shown to improve with surgical correction of the underlying deficiency. Subtle microinstability, particularly from microtraumatic or atraumatic causes, is an evolving concept with early surgical treatment results that are promising.

View details for DOI 10.1016/j.csm.2010.12.008

View details for Web of Science ID 000289811500010

View details for PubMedID 21419960

Review of tennis serve motion analysis and the biomechanics of three serve types with implications for injury SPORTS BIOMECHANICS Abrams, G. D., Sheets, A. L., Andriacchi, T. P., Safran, M. R. 2011; 10 (4): 378-390


The tennis serve has the potential for musculoskeletal injury as it is an overhead motion and is performed repetitively during play. Early studies evaluating the biomechanics and injury potential of the tennis serve utilized skin-based marker technologies; however, markerless motion measurement systems have recently become available and have obviated some of the problems associated with the marker-based technology. The late cocking and early acceleration phases of the kinetic chain of the service motion produce the highest internal forces and pose the greatest risk of injury during the service motion. Previous biomechanical data on the tennis serve have primarily focused on the flat serve, with some data on the kick serve, and very little published data elucidating the biomechanics of the slice serve. This review discusses the injury potential of the tennis serve with respect to the four phases of the service motion, the history, and early findings of service motion evaluation, as well as biomechanical data detailing the differences between the three types of serves and how this may relate to injury prevention, rehabilitation, and return to play.

View details for DOI 10.1080/14763141.2011.629302

View details for Web of Science ID 000299832400010

View details for PubMedID 22303788

Case Report Bifid Iliopsoas Tendon Causing Refractory Internal Snapping Hip CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Shu, B., Safran, M. R. 2011; 469 (1): 289-293


Treatment of painful internal snapping hip (coxa saltans) via arthroscopic lengthening or release of the iliopsoas tendon is becoming preferred over open techniques because of the benefits of minimal dissection, the ability to address concomitant intraarticular disorders, and a low complication rate. Persistent snapping after release is uncommon, especially when performed arthroscopically. Reported causes include incomplete release, intraarticular disorders, and incorrect diagnosis. Anatomic variants are not discussed in the orthopaedic literature.We report a case of an 18-year-old softball player with internal snapping hip treated with arthroscopic iliopsoas release in the peripheral compartment. Postoperatively, the athlete continued to have painful snapping. Repeat arthroscopy with a larger capsulotomy revealed a bifid iliopsoas tendon causing refractory internal snapping hip, which resolved after revision arthroscopic release.Bifid iliopsoas tendon as a cause of persistent snapping of the hip has not been reported in the orthopaedic literature. Prior sonographic and anatomic studies suggest the bifid iliopsoas tendon exists but is uncommon. PURPOSE AND CLINICAL RELEVANCE: Recognition that a bifid iliopsoas tendon may be the source of painful internal snapping hip is important to prevent clinical failure of surgical management of the internal snapping hip. The differential diagnosis of failed iliopsoas lengthening surgery should include the consideration of an incompletely lengthened tendon attributable to bifid iliopsoas tendon anatomy. Prevention of this complication includes making a large enough capsulotomy to identify the tendon and to ensure it is not bifid.

View details for DOI 10.1007/s11999-010-1452-z

View details for Web of Science ID 000286938400040

View details for PubMedID 20593254

The Athlete's Elbow Preface CLINICS IN SPORTS MEDICINE Safran, M. R. 2010; 29 (4): XIII-XV

View details for DOI 10.1016/j.csm.2010.06.002

View details for Web of Science ID 000283562000002

View details for PubMedID 20883895

Ulnar Collateral Ligament Injury in the Overhead Athlete CLINICS IN SPORTS MEDICINE Hariri, S., Safran, M. R. 2010; 29 (4): 619-?


The ulnar collateral ligament (UCL), particularly the anterior portion of the anterior oblique ligament, is the primary static contributor to elbow valgus stability. UCL injuries are most common in athletes participating in overhead sports. Acute and chronic injuries to the UCL result in valgus instability, which may predispose the athlete to the development of disabling secondary elbow conditions. Provocative physical examination maneuvers include the valgus abduction test, the modified milking maneuver, and the moving valgus stress test. Plain radiographs and magnetic resonance imaging are the most common imaging modalities, although ultrasonography and computed tomography arthrograms can alternatively be used. UCL injuries can be treated initially with rest, anti-inflammatory medications, bracing, and/or physical therapy. Acute avulsion injuries can be repaired, especially in those under 20 years of age, but most UCL tears are now treated with reconstruction. Modifications of the Jobe figure-of-8 technique, and now the Altchek docking technique, are the most common reconstruction techniques. Many new and hybrid techniques have been described with limited clinical experience in the literature. Current techniques offer the athlete a greater than 90% chance of return to play at their preinjury level.

View details for DOI 10.1016/j.csm.2010.06.007

View details for Web of Science ID 000283562000008

View details for PubMedID 20883901

The Acetabular Labrum: Anatomic and Functional Characteristics and Rationale for Surgical Intervention JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Safran, M. R. 2010; 18 (6): 338-345


The past decade has seen unprecedented growth in the number of hip arthroscopies. Acetabular labral tears are the leading indication for arthroscopy of this joint. However, labral anatomy and function, as well as the effects of labral tears and surgical outcomes, have only recently been studied. Labral tears may cause pain and microinstability of the hip joint. They also may increase friction within the joint, cartilage consolidation, and strain within the articular cartilage, thereby possibly resulting in accelerated degeneration of the joint. Partial labrectomy and labral repair are the current surgical options, and basic science data suggest that labral repairs can heal and subsequently restore function. However, a good, validated outcomes measure to adequately assess active patients with a painful nonarthritic hip is needed to determine the efficacy of such repair and aid in managing patient expectations.

View details for Web of Science ID 000278238500006

View details for PubMedID 20511439

Arthroscopic Femoral Osteoplasty/Chielectomy for Cam-type Femoroacetabular Impingement in the Athlete SPORTS MEDICINE AND ARTHROSCOPY REVIEW Vaughn, Z. D., Safran, M. R. 2010; 18 (2): 90-99


Femoroacetabular impingement (FAI) represents an underlying bony abnormality of either the femoral head-neck junction or acetabulum, or most commonly, both. This often is associated with damage to intra-articular structures, primarily the labrum and chondral surfaces. Like pincer impingement, cam impingement has been associated with pain, limited hip range of motion, pain affecting athletic performance, and has been linked to the development of osteoarthritis. Cam impingement is the loss of offset of the femoral head-neck junction associated with loss of sphericity of the femoral head. Isolated cam impingement, although more common than isolated pincer impingement, it is much less common than both cam and pincer coexisting in people with FAI. Classically, the patient with isolated cam impingement is a young athletic male near 20 years of age. The classic pathology associated with the cam lesion is an acetabular articular cartilage injury in the anterosuperior acetabulum that is fairly well defined and may be deep, 1 to 1.5 cm from the acetabular rim, initially sparing the labrum, but eventually leading to labral detachment from the underlying bone. Treatment generally focuses on restoring the femoral head-neck offset by removing the excess bone. This article will review the underlying pathology of cam-type FAI, the evaluation and diagnosis, arthroscopic treatment, and reported outcomes.

View details for DOI 10.1097/JSA.0b013e3181dfce63

View details for Web of Science ID 000278105700006

View details for PubMedID 20473127

The Evidence for Surgical Repair of Articular Cartilage in the Knee JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Safran, M. R., Seiber, K. 2010; 18 (5): 259-266


The complex structure and biomechanical function of articular cartilage make chondral injuries a management challenge. Articular cartilage has limited, if any, capacity to heal and/or regenerate. Although the natural history of articular cartilage lesions has not been clearly studied, significant injuries are believed to progress, resulting in degenerative arthritis of the joint. Changes have been made in surgical techniques in an attempt to better manage these lesions, and a large industry has been built around arthroscopic and open surgical procedures for managing cartilage repair. However, there is limited evidence that any intervention significantly alters the natural history of these lesions. Randomized trials have been done to examine the outcomes of common restoration procedures performed in the United States today, such as microfracture, osteochondral autograft transfer, and autologous chondrocyte implantation. Because the natural history of articular cartilage lesions has not been defined, we can assess the utility of surgical interventions only by comparing methods.

View details for Web of Science ID 000277310300002

View details for PubMedID 20435876

Diagnosis and management of superior labrum anterior posterior lesions in overhead athletes BRITISH JOURNAL OF SPORTS MEDICINE Abrams, G. D., Safran, M. R. 2010; 44 (5): 311-318


Shoulder pain is a common complaint in overhead athletes, and superior labrum anterior posterior (SLAP) lesions are a common cause of this pain. The pathological cascade which results in the SLAP lesion consists of a combination of posterior inferior capsular tightness and scapular dyskinesis, resulting in a 'peel back' phenomenon at the biceps anchor and leading to the SLAP tear. Physical exam tests vary in their sensitivity and specificity in detecting SLAP lesions, so MRI is helpful in demonstrating the anatomical alteration. Treatment can be conservative, with posterior inferior capsular stretching and scapular open and closed chain exercises. Many SLAP lesions in overhead athletes require surgical treatment that involves repair of the labrum back to the glenoid. Treatment of concomitant injuries such as rotator cuff tears and Bankart lesions in conjunction with the SLAP repair may be necessary.

View details for DOI 10.1136/bjsm.2009.070458

View details for Web of Science ID 000276368100005

View details for PubMedID 20371556

Injuries about the shoulder in skiing and snowboarding BRITISH JOURNAL OF SPORTS MEDICINE McCall, D., Safran, M. R. 2009; 43 (13): 987-992


There has been a decrease in the overall injury rate, particularly the rate of lower-extremity injuries, for alpine skiing, with a resultant increase in the ratio of upper-extremity to lower-extremity injuries. The upper extremity is injured nearly twice as often during snowboarding than alpine skiing, with approximately half of all snowboarding injuries involving the upper extremity. Shoulder injuries are likely under-reported, as many patients seek evaluation for minor shoulder injuries with their local physicians, and not at the ski medical clinic, where most epidemiology studies obtain their data. Shoulder injuries account for 4 to 11% of all alpine skiing injuries and 22 to 41% of upper-extremity injuries. During snowboarding, shoulder injuries account for 8 to 16% of all injuries and 20 to 34% of upper-extremity injuries. Falls are the most common mechanism of shoulder injury, in addition to pole planting during skiing and aerial manoeuvres during snowboarding. Common shoulder injuries during skiing and snowboarding are rotator cuff strains, glenohumeral dislocations, acromioclavicular separations and clavicle fractures. It is still unclear, when comparing snowboarding and skiing injury data, which sport has the higher incidence of shoulder injuries. Stratifying shoulder injuries by type allows better delineation as to which sport has an increased incidence of certain injury patterns. The differing mechanisms of injury combined with distinct equipment for each sport plays a role in the type and frequency of shoulder injuries seen in these two subgroups. With the increased ratio of upper- to lower-extremity injuries during alpine skiing and the boom in popularity of snowboarding, shoulder injuries are seen with increasing frequency by those who care for alpine sport injuries. According to recent epidemiological data, only clavicle and humerus fractures have shown increased rates of incidence among alpine skiers. Over the past 30 years, there has been a general decrease in both upper- and lower-extremity injuries which can be attributed to improved designs of protective equipment, increased awareness of injury patterns and emphasis on prevention. In the future, physicians and therapists who treat this population must be comfortable and confident in their treatment algorithms to help keep skiers and snowboarders conditioned and ready for the slopes and develop strategies for the prevention of upper-extremity injuries associated with these activities.

View details for DOI 10.1136/bjsm.2009.068767

View details for Web of Science ID 000272170300007

View details for PubMedID 19945981

Graft Orientation Influences the Knee Flexion Moment During Walking in Patients With Anterior Cruciate Ligament Reconstruction AMERICAN JOURNAL OF SPORTS MEDICINE Scanlan, S. F., Blazek, K., Chaudhari, A. M., Safran, M. R., Andriacchi, T. P. 2009; 37 (11): 2173-2178


Anterior cruciate ligament graft orientation has been proposed as a potential mechanism for failure of single-bundle anterior cruciate ligament reconstruction and has been considered important in the restoration of normal ambulatory knee mechanics.To evaluate the possibility that patients adapt their mechanics of walking to the orientation of the anterior cruciate ligament graft. This was determined by testing the hypothesis that peak external knee flexion moment (net quadriceps moment) during walking in patients with anterior cruciate ligament reconstruction is correlated with coronal and sagittal anterior cruciate ligament graft orientations.Cross-sectional study; Level of evidence, 3.Gait analysis was performed to assess dynamic knee function during walking in 17 subjects with unilateral anterior cruciate ligament reconstructions. Magnetic resonance imaging was used to measure coronal and sagittal anterior cruciate ligament graft orientations.A negative correlation was observed between peak external knee flexion moment during walking and coronal angle of the anterior cruciate ligament graft (1.0 m/s walking speed, r = -0.87, P < .001; 1.3 m/s, r = -0.66, P = .004; 1.6 m/s, r = -0.24, P > .05); no correlation was found with the sagittal graft angle (1.0 m/s walking speed, r = 0.21, P > .05; 1.3 m/s, r = 0.20, P > .05; 1.6 m/s, r = 0.13, P > .05).The negative correlation between peak external knee flexion moment during walking and the coronal angle of the anterior cruciate ligament graft indicates that as the anterior cruciate ligament graft is placed in a more vertical coronal orientation, patients reduce their net quadriceps usage during walking.This finding supports the hypothesis that graft placement plays a critical role in the restoration of normal ambulatory mechanics after anterior cruciate ligament reconstruction and thus could provide a partial explanation for the increased incidence of premature osteoarthritis at long-term follow-up in patients with anterior cruciate ligament reconstruction.

View details for DOI 10.1177/0363546509339574

View details for Web of Science ID 000271216600012

View details for PubMedID 19729363

Stress fracture of the acetabular rim: arthroscopic reduction and internal fixation. A case report. journal of bone and joint surgery. American volume Epstein, N. J., Safran, M. R. 2009; 91 (6): 1480-1486

View details for DOI 10.2106/JBJS.H.01499

View details for PubMedID 19487528

The use of scaffolds in the management of art articular cartilage injury JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Safran, M. R., Kim, H., Zaffagnini, S. 2008; 16 (6): 306-311


Managing articular cartilage injury continues to be a difficult challenge for the clinician. Although the short- and intermediate-term results of autologous chondrocyte implantation appear to be favorable, resources are being directed toward research to improve the technology. One promising area of investigation is the combination of cultured chondrocytes with scaffolds. Clinicians desire techniques that may be implanted easily, reduce surgical morbidity, do not require harvesting of other tissues, exhibit enhanced cell proliferation and maturation, have easier phenotype maintenance, and allow for efficient and complete integration with surrounding articular cartilage. The characteristics that make scaffolds optimal for clinical use are that they be biocompatible, biodegradable, permeable, reproducible, mechanically stable, noncytotoxic, and capable of serving as a temporary support for the cells while allowing for eventual replacement by matrix components synthesized by the implanted cells. Clinical experience is growing with three scaffold-based cartilage repair techniques, each using a different type of scaffold material: matrix-induced autologous chondrocyte implantation, a hyaluronic acid-based scaffold, and a composite polylactic/polyglycolic acid polymer fleece. Clinical results are encouraging. Future directions in scaffold-based cartilage repair include bioactive and spatially oriented scaffolds.

View details for Web of Science ID 000256280600002

View details for PubMedID 18524981

Injury of the distal biceps at the musculotendinous junction JOURNAL OF SHOULDER AND ELBOW SURGERY Schamblin, M. L., Safran, M. R. 2007; 16 (2): 208-212


Although complete rupture of the distal biceps tendon at the osseous insertion has been well documented in the literature, musculotendinous ruptures of the distal biceps remain exceedingly uncommon. In this report, we present a series of 6 distal biceps musculotendinous ruptures in 6 different patients, verified either with magnetic resonance imaging or by direct visualization at surgical exploration. In 5 of 6 patients, a single traumatic injury was reported, whereas the sixth reported 2 episodes of injury and pain occurring approximately 1 week apart. A common mechanism of injury seems to prevail in this type of injury: glenohumeral elevation with the elbow extended and the forearm in supination. Although surgical outcomes of distal biceps osseous avulsions frequently lead to excellent results, the surgical options for musculotendinous junction injuries are limited, with outcome studies lacking. These 6 patients, who did not undergo repair, obtained a mean score of 97.5 on the Mayo Clinic Performance Index for the Elbow. Symptoms of musculotendinous injury to the distal biceps are similar to tendinitis or complete or partial avulsion of this muscle-tendon unit. The examination reveals an intact distal biceps tendon. In patients with a mechanism of injury consistent with a musculotendinous injury of the distal biceps, radiographic modalities, particularly magnetic resonance imaging, are recommended to confirm the diagnosis to differentiate it from the more common distal biceps tendon avulsion, or partial rupture, to limit the morbidity associated with potentially unnecessary operative procedures.

View details for DOI 10.1016/j.jse.2006.06.009

View details for Web of Science ID 000245426200013

View details for PubMedID 17169581

A peek into the possible future of management of articular cartilage injuries: Gene therapy and scaffolds for cartilage repair JOURNAL OF ORTHOPAEDIC & SPORTS PHYSICAL THERAPY Kim, H. T., Zaffagnini, S., Mizuno, S., Abelow, S., Safran, M. R. 2006; 36 (10): 765-773


Two rapidly progressing areas of research will likely contribute to cartilage repair procedures in the foreseeable future: gene therapy and synthetic scaffolds. Gene therapy refers to the transfer of new genetic information to cells that contribute to the cartilage repair process. This approach allows for manipulation of cartilage repair at the cellular and molecular level. Scaffolds are the core technology for the next generation of autologous cartilage implantation procedures in which synthetic matrices are used in conjunction with chondrocytes. This approach can be improved further using bioreactor technologies to enhance the production of extracellular matrix proteins by chondrocytes seeded onto a scaffold. The resulting "neo-cartilage implant" matures within the bioreactor, and can then be used to fill cartilage defects.

View details for DOI 10.2519/jospt.2006.2284

View details for Web of Science ID 000241065800006

View details for PubMedID 17063838

Short-term effectiveness of hyperthermia for supraspinatus tendinopathy in athletes - A short-term randomized controlled study AMERICAN JOURNAL OF SPORTS MEDICINE Giombini, A., Di Cesare, A., Safran, M. R., Ciatti, R., Maffulli, N. 2006; 34 (8): 1247-1253


Hyperthermia has been introduced as a physical therapy modality for soft tissue injuries.The authors tested the null hypothesis that there are no short-term differences after the use of hyperthermia, ultrasound, and exercises for tendinopathy of the supraspinatus tendon.Randomized controlled trial; Level of evidence, 1.The authors studied 37 athletes (29 men, 8 women; mean age, 26.7 +/- 5.8 years; range, 19-43 years) with supraspinatus tendinopathy who had had symptoms between 3 and 6 months. Subjects were randomly assigned to 3 groups. Group A (n = 14) received hyperthermia at 434 MHz. Group B (n = 12) received continuous ultrasound at 1 MHz at an intensity of 2.0 w/cm(2) 3 times a week. Group C (n = 11) undertook exercises, consisting of pendular swinging and stretching exercises 5 minutes twice a day every day. All interventions were undertaken for 4 weeks. Subjects were evaluated at baseline, immediately on completion of treatment, and at 6 weeks after the end of the intervention using mean pain score for pain at night, during movement, and at rest on a visual analog scale; pain on resisted movement and painful arc on active abduction between 40 degrees and 120 degrees on a 4-point scale; and Constant score.Patients who received hyperthermia experienced significantly better pain relief than did patients receiving ultrasound or exercises: group A, 5.96 to 1.2 (P = .03); group B, 6.3 to 5.15 (P = .10); group C, 6.1 to 4.9 (P = .09).Hyperthermia at 434 MHz appears safe and effective in the short term for the management of supraspinatus tendinopathy.

View details for DOI 10.1177/0363546506287827

View details for Web of Science ID 000239168600005

View details for PubMedID 16636345

MRI analysis of in vivo meniscal and tibiofemoral kinematics in ACL-deficient and normal knees JOURNAL OF ORTHOPAEDIC RESEARCH Shefelbine, S. J., Ma, C. B., Lee, K., Schrumpf, M. A., Patel, P., Safran, M. R., Slavinsky, J. P., Majumdar, S. 2006; 24 (6): 1208-1217


The objectives of this study were to analyze simultaneously meniscal and tibiofemoral kinematics in healthy volunteers and anterior cruciate ligament (ACL)-deficient patients under axial load-bearing conditions using magnetic resonance imaging (MRI). Ten healthy volunteers and eight ACL-deficient patients were examined with a high-field, closed MRI system. For each group, both knees were imaged at full extension and partial flexion ( approximately 45 degrees ) with a 125N compressive load applied to the foot. Anteroposterior and medial/lateral femoral and meniscal translations were analyzed following three-dimensional, landmark-matching registration. Interobserver and intraobserver reproducibilities were less than 0.8 mm for femoral translation for image processing and data analysis. The position of the femur relative to the tibia in the ACL-deficient knee was 2.6 mm posterior to that of the contralateral, normal knee at extension. During flexion from 0 degrees to 45 degrees , the femur in ACL-deficient knees translated 4.3 mm anteriorly, whereas no significant translation occurred in uninjured knees. The contact area centroid on the tibia in ACL-deficient knees at extension was posterior to that of uninjured knees. Consequently, significantly less posterior translation of the contact centroid occurred in the medial tibial condyle in ACL-deficient knees during flexion. Meniscal translation, however, was nearly the same in both groups. Axial load-bearing MRI is a noninvasive and reproducible method for evaluating tibiofemoral and meniscal kinematics. The results demonstrated that ACL deficiency led to significant changes in bone kinematics, but negligible changes in the movement of the menisci. These results help explain the increased risk of meniscal tears and osteoarthritis in chronic ACL deficient knees.

View details for DOI 10.1002/jor.20139

View details for Web of Science ID 000237825600011

View details for PubMedID 16652339

Postero-medial elbow problems in the adult athlete BRITISH JOURNAL OF SPORTS MEDICINE Eygendaal, D., Safran, M. R. 2006; 40 (5): 430-434


The ligamentous, osseous, musculotendinous, and neural structures at the postero-medial side of the elbow are at risk for various injuries in overhead athletes. The combination of valgus and extension overload during overhead activities results in tensile forces along the medial stabilising structures, with compression on the lateral compartment and shear stress posteriorly. The combination of tensile forces medially and shear forces posteriorly can result in ulnar collateral ligament (UCL) tears, flexor-pronator mass injuries, neuritis of the ulnar nerve, posterior impingement, and olecranon stress fractures. Most symptomatic conditions of the overhead athlete can be treated conservatively initially. In cases where conservative treatment is unsuccessful surgical intervention is indicated. Recent advances in arthroscopic surgical techniques and ligamentous reconstruction ensure that the prognosis for return to pre-injury level is good.

View details for DOI 10.1136/bjsm.2005.025437

View details for Web of Science ID 000236994800013

View details for PubMedID 16632574

Osteochondritis dissecans of the knee JOURNAL OF THE AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS Crawford, D. C., Safran, M. R. 2006; 14 (2): 90-100


Osteochondritis dissecans is a condition of the joints that appears to affect subchondral bone primarily, with secondary effects on articular cartilage. With progression, this pathology may present clinically with symptoms related to the integrity of the articular cartilage. Early signs, associated with intact cartilage, may be related to a softening phenomenon and alteration in the mechanical properties of cartilage. Later stages, because of the lack of underlying support of the cartilage, can present with signs of articular cartilage separation, cartilage flaps, loose bodies, inflammatory synovitis, persistent or intermittent joint effusion, and, in severe cases, secondary joint degeneration. Selecting and recommending a surgical intervention require balancing application of nonsurgical interventions with assessment of the degree of articular cartilage stability and the potential for spontaneous recovery.

View details for Web of Science ID 000235226900004

View details for PubMedID 16467184

Avoidance and management of intra-articular complications of anterior cruciate ligament reconstruction. Instructional course lectures Safran, M. R., Greene, H. S. 2006; 55: 475-488


An estimated 70,000 to 100,000 anterior cruciate ligament reconstructions are performed each year in the United States. With the increasing number of anterior cruciate ligament surgeries being performed, a concomitant increase in intraoperative complications can be expected. Complications include those associated with tunnel placement, notchplasty, graft fixation and advancement, suture laceration, graft laceration, guidewire insertion and removal, intra-articular hardware, posterior cruciate ligament laceration, compartment syndrome, and vascular injury.

View details for PubMedID 16958482

Extensor mechanism disruption after contralateral middle third patellar tendon harvest for anterior cruciate ligament revision reconstruction - art. no. E1 ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY Busfield, B. T., Safran, M. R., Cannon, W. D. 2005; 21 (10): 1268-1268


The contralateral central third patellar tendon autograft is a reliable graft choice for revision, and recently, for primary reconstruction of the anterior cruciate ligament (ACL). We report 2 complications including a lateral third tibial tuberosity fracture and a distal patellar tendon avulsion with contralateral patellar tendon autograft with disruption of the extensor mechanism of the donor knee. A patient sustained a lateral tibial tuberosity fracture of the donor knee and underwent open reduction and internal fixation. At 1-year follow-up, she had no extensor lag and full range of motion. Another patient sustained a distal patellar tendon avulsion of the donor knee and underwent primary repair. Three years postoperatively, she had a full range of motion and no extensor lag. Although contralateral middle third patellar tendon autograft for primary and revision ACL reconstruction is established in the literature, extensor mechanism complications can occur. Technical considerations are important to avoid weakening the remaining patellar tendon insertion. Postoperative nerve blocks or local anesthetics may alter pain feedback for regulation of weight bearing and contribute to overload of the donor knee.

View details for DOI 10.1016/j.arthro.2005.07.010

View details for Web of Science ID 000232907700019

View details for PubMedID 16226659

Effects of elbow flexion and forearm rotation on valgus laxity of the elbow. journal of bone and joint surgery. American volume Safran, M. R., McGarry, M. H., Shin, S., Han, S., Lee, T. Q. 2005; 87 (9): 2065-2074


Clinical evaluation of valgus elbow laxity is difficult. The optimum position of elbow flexion and forearm rotation with which to identify valgus laxity in a patient with an injury of the ulnar collateral ligament of the elbow has not been determined. The purpose of the present study was to determine the effect of forearm rotation and elbow flexion on valgus elbow laxity.Twelve intact cadaveric upper extremities were studied with a custom elbow-testing device. Laxity was measured with the forearm in pronation, supination, and neutral rotation at 30 degrees, 50 degrees, and 70 degrees of elbow flexion with use of 2 Nm of valgus torque. Testing was conducted with the ulnar collateral ligament intact, with the joint vented, after cutting of the anterior half (six specimens) or posterior half (six specimens) of the anterior oblique ligament of the ulnar collateral ligament, and after complete sectioning of the anterior oblique ligament. Laxity was measured in degrees of valgus angulation in different positions of elbow flexion and forearm rotation.There were no significant differences in valgus laxity with respect to elbow flexion within each condition. Overall, for both groups of specimens (i.e., specimens in which the anterior or posterior half of the anterior oblique ligament was cut), neutral forearm rotation resulted in greater valgus laxity than pronation or supination did (p < 0.05). Transection of the anterior half of the anterior oblique ligament did not significantly increase valgus laxity; however, transection of the posterior half resulted in increased valgus laxity in some positions. Full transection of the anterior oblique ligament significantly increased valgus laxity in all positions (p < 0.05).The results of this in vitro cadaveric study demonstrated that forearm rotation had a significant effect on varus-valgus laxity. Laxity was always greatest in neutral forearm rotation throughout the ranges of elbow flexion and the various surgical conditions.The information obtained from the present study suggests that forearm rotation affects varus-valgus elbow laxity. Additional investigation is warranted to determine if forearm rotation should be considered in the evaluation and treatment of ulnar collateral ligament injuries of the elbow joint.

View details for PubMedID 16140822

Soft-tissue stabilizers of the elbow Closed Meeting of the American-Shoulder-and-Elbow-Surgeons Safran, M. R., Baillargeon, D. MOSBY-ELSEVIER. 2005: 179S–185S


Elbow stability is afforded by both static and dynamic structures. Static structures include the complex bony architecture and soft-tissue stabilizers. Knowledge of the anatomy and biomechanics of the stabilizers is important to understand, diagnose, and treat elbow instability. Bony anatomy, detailed elsewhere, contributes to the inherent stability of the elbow. The static soft-tissue stabilizers consist of the anterior and posterior joint capsule and both medial and lateral collateral ligament complexes. Additional stability is conferred by dynamic structures--the muscles crossing the elbow joint.

View details for DOI 10.1016/j.jse.2004.09.032

View details for Web of Science ID 000227328400026

View details for PubMedID 15726079

Elbow injuries in athletes CLINICS IN SPORTS MEDICINE Safran, M. R. 2004; 23 (4): XVII-XIX

View details for DOI 10.1016/j.csm.2004.06.009

View details for Web of Science ID 000224471500002

View details for PubMedID 15474217

Ulnar collateral ligament injury in the overhead athlete: diagnosis and treatment CLINICS IN SPORTS MEDICINE Safran, M. R. 2004; 23 (4): 643-?


The ulnar collateral ligament (UCL) is more commonly injured than previously suggested. Injury to this ligament can result in secondary symptoms and problems in other parts of the elbow, including the ulnar nerve, the flexor-pronator musculotendinous unit, the radiocapitellar joint, and the posterior compartment of the elbow, in addition to being a cause of loose bodies within the elbow. This article briefly reviews the anatomy, biomechanics, and pathophysiology of injury, in addition to discussing evaluation and treatment of the athlete with an injured UCL.

View details for DOI 10.1016/j.csm.2004.05.002

View details for Web of Science ID 000224471500012

View details for PubMedID 15474227

Nerve injury about the shoulder in athletes, Part 2 - Long thoracic nerve, spinal accessory nerve, burners/stingers, thoracic outlet syndrome AMERICAN JOURNAL OF SPORTS MEDICINE Safran, M. R. 2004; 32 (4): 1063-1076


Nerve injuries about the shoulder in athletes are being recognized with increasing frequency. Prompt and correct diagnosis of these injuries is important to treat the patient and to understand the potential complications and natural history, so as to counsel our athletes appropriately. This 2-part article is a review and an overview of the current state of knowledge regarding some of the more common nerve injuries seen about the shoulder in athletes, including long thoracic nerve, spinal accessory nerve, burners and stingers, and thoracic outlet syndrome. Each of these clinical entities will be discussed independently, reviewing the anatomy, mechanism of injury, patient presentation (history and examination), the role of additional diagnostic studies, differential diagnosis, and management.

View details for DOI 10.1177/0363546504265193

View details for Web of Science ID 000221706200031

View details for PubMedID 15150060

Nerve injury about the shoulder in athletes, part 1 - Suprascapular nerve and axillary nerve AMERICAN JOURNAL OF SPORTS MEDICINE Safran, M. R. 2004; 32 (3): 803-819


Nerve injuries about the shoulder in athletes are being recognized with increasing frequency. Prompt and correct diagnosis of these injuries is important to treat the patient and to understand the potential complications and natural history so as to appropriately counsel athletes. This 2-part article is a review and an overview of the current state of knowledge regarding some of the more common nerve injuries seen about the shoulder in athletes.

View details for DOI 10.1177/0363546504264582

View details for Web of Science ID 000220915100032

View details for PubMedID 15090401

Distal biceps tendon ruptures - Incidence, demographics, and the effect of smoking Annual Meeting of the Knee-Society/Association of-Hip-and-Knee-Surgeons Safran, M. R., Graham, S. M. SPRINGER. 2002: 275–83


The purpose of the current study was to determine the incidence of distal biceps tendon ruptures within a defined population, to describe the demographics of affected individuals, and to identify potential risk factors. The healthcare system in this study provides care to a known number of members in an area defined by zip codes and proximity to the medical center. Medical records for all members who presented with injuries about the elbow during a 5-year period were reviewed. Thirteen men and one woman with an average age of 47 years comprised the study population. The dominant extremity was involved in 86% of patients. All patients described a mechanism involving excessive eccentric tension as the arm was forced from a flexed position. The incidence of injury in the membership population averaged 1.2 ruptures per 100,000 patients per year. Forty-three percent reported regular tobacco use, whereas only 9% of all members were smokers. A Poisson regression analysis revealed a 7.5 times greater risk of distal biceps tendon rupture in patients who smoke. The incidence of distal biceps tendon ruptures is 1.2 per 100,000 patients, with the majority in the dominant elbow of men who smoke and who are in their fourth decade of life.

View details for DOI 10.1097/01.blo.0000026560.55792.02

View details for Web of Science ID 000179273100042

View details for PubMedID 12439270

Sideline management of common dislocations. Current sports medicine reports Hodge, D. K., Safran, M. R. 2002; 1 (3): 149-155


This article reviews sideline assessment and treatment of commonly encountered joint dislocations. Although often deferred for formal management in an emergency room, many of these injuries can be safely and appropriately reduced by experienced hands on the field. This text provides a practical approach, outlining mechanism, presentation and physical exam, reduction, aftercare, and return to sport for many common joint dislocations. Emphasis is placed on awareness of possible complications of injury and from treatment, proper documentation of neurovascular status before and after intervention, and formal radiographic confirmation following joint reduction. When appropriate, the immediate sideline management of common joint dislocations may minimize morbidity encountered with later treatment in the hospital setting.

View details for PubMedID 12831707

Shoulder proprioception in baseball pitchers JOURNAL OF SHOULDER AND ELBOW SURGERY Safran, M. R., Borsa, P. A., Lephart, S. M., Fu, F. H., Warner, J. J. 2001; 10 (5): 438-444


We examined proprioceptive differences between the dominant and nondominant shoulders of 21 collegiate baseball pitchers without a history of shoulder instability or surgery. A proprioceptive testing device was used to measure kinesthesia and joint position sense. Joint position sense was significantly (P =.05) more accurate in the nondominant shoulder than in the dominant shoulder when starting at 75% of maximal external rotation and moving into internal rotation. There were no significant differences for proprioception in the other measured positions or with kinesthesia testing. Six pitchers with recent shoulder pain had a significant (P =.04) kinesthetic deficit in the symptomatic dominant shoulder compared with the asymptomatic shoulder, as measured in neutral rotation moving into internal rotation. The net effect of training, exercise-induced laxity, and increased external rotation in baseball pitchers does not affect proprioception, although shoulder pain, possibly due to rotator cuff inflammation or tendinitis, is associated with reduced kinesthetic sensation.

View details for DOI 10.1067/mse.2001.118004

View details for Web of Science ID 000171926100007

View details for PubMedID 11641701

Musculoskeletal injuries in the young tennis player CLINICS IN SPORTS MEDICINE Ben Kibler, W., Safran, M. R. 2000; 19 (4): 781-?


Tennis is becoming increasingly popular, especially with young athletes. Despite recent advances in epidemiologic research of tennis injuries, there still is a need for more injury research in all of the racquet sports. The data that does exist show that the young athlete is susceptible to injury in these different sports. Injury patterns in the skeletally immature racquet sports athlete are becoming apparent. Although most of the sports result in similar injury patterns, such as a predominance of lower extremity injury, there are differences. It appears that the physical demands of the sport are becoming more clearly documented, and the adaptive response to these demands is becoming understood. The adaptive response reveals a common origin for many of the injuries in the different sports. This is related most often to repetitive microtrauma with resultant loss in flexibility and strength. The sports medicine practitioner must understand these differences, know the demands, do serial musculoskeletal evaluations for maladaptations, and adhere to a periodized prehabilitation program of preventative exercises to maximize performance and minimize injury risk.

View details for Web of Science ID 000089536000012

View details for PubMedID 11019740

Zoster paresis of the shoulder - Case report and review of the literature CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Yaszay, B., Jablecki, C. K., Safran, M. R. 2000: 112-118


More than 95% of people in the United States are infected with the varicella zoster virus at some time in life, and this infection usually is manifested as chicken pox during childhood. The virus then establishes a latent infection of sensory ganglia, from which it may reactivate many years later to cause herpes zoster (shingles), a cutaneous painful rash along a dermatomal distribution. Less commonly, the varicella zoster virus may result in myotomal motor weakness or paralysis in addition to a painful dermatomal rash. A case of unilateral left C5-C6 segmental paresis attributable to herpes zoster in an otherwise healthy individual and a current review of the literature are presented. A case of zoster paresis of the shoulder muscles is presented to remind the orthopaedic community that this diagnosis may be confused with other diagnoses, including rotator cuff tear, and should be considered in the differential diagnosis of shoulder pain and shoulder girdle muscle weakness.

View details for Web of Science ID 000088559100017

View details for PubMedID 10943192

Proprioception in the posterior cruciate ligament deficient knee Specialty Day Meeting of the American-Orthopaedic-Society-for-Sports-Medicine / 63rd Annual Meeting of the American-Academy-of-Orthopaedic-Srgeons Safran, M. R., Allen, A. A., Lephart, S. M., Fu, F. H., Harner, C. D. SPRINGER. 1999: 310–17


This study was undertaken to evaluate knee proprioception in patients with isolated unilateral posterior cruciate ligament (PCL) injuries. Eighteen subjects with isolated PCL tears were studied 1-234 months after injury. The threshold to detect passive motion (TTDPM) was used to evaluate kinesthesia and the ability to passively reproduce passive positioning (RPP) to test joint position sense. Two starting positions were tested in all knees: 45 degrees (middle range) and 110 degrees (end range) to evaluate knee proprioception when the PCL is under different amounts of tension. TTDPM and RPP were tested as the knee moved into flexion and extension from both starting positions. A statistically significant reduction in TTDPM was identified in PCL-injured knees tested from the 45 degrees starting position, moving into flexion and extension. RPP was statistically better in the PCL-deficient knee as tested from 110 degrees moving into flexion and extension. No difference was identified in the TTDPM starting at 110 degrees or in RPP with the presented angle at 45 degrees moving into flexion or extension. These subtle but statistically significant findings suggest that proprioceptive mechanoreceptors may play a clinical role in PCL-intact and PCL-deficient patients. Further, it appears that kinesthesia and joint position sense may function through different mechanisms.

View details for Web of Science ID 000083126700009

View details for PubMedID 10525701

Peroneal tendon subluxation in athletes: new exam technique, case reports, and review MEDICINE AND SCIENCE IN SPORTS AND EXERCISE Safran, M. R., O'Malley, D., Fu, F. H. 1999; 31 (7): S487-S492


Traumatic peroneal tendon subluxation is an uncommon cause of ankle pain. As a result, the diagnosis is often delayed. A new technique of examining the patient in the prone position, allowing for easier visualization of the subluxation or dislocation, is described. Three illustrative cases, including a rare case of midsubstance rupture of the peroneal retinaculum are presented along with a review the literature. An acute repair in athletes and in those patients who do not want to risk the chance of a 40-50% failure rate after 4-6 wk of casting is currently recommended. Surgical repair can be facilitated using Mitek suture anchors for acute, symptomatic chronic, and subacute injuries. Deepening of the groove is performed only in those patients that have no sulcus or a convexity of the groove.

View details for Web of Science ID 000081388800009

View details for PubMedID 10416549

Lateral ankle sprains: a comprehensive review - Part 2: treatment and rehabilitation with an emphasis on the athlete MEDICINE AND SCIENCE IN SPORTS AND EXERCISE Safran, M. R., Zachazewski, J. E., Benedetti, R. S., Bartolozzi, A. R., Mandelbaum, R. 1999; 31 (7): S438-S447


This is the second part of a two-part comprehensive review of lateral ankle sprains. In the first part of our review, we discussed the etiology, natural history, pathoanatomy, mechanism of injury, histopathogenesis of healing, and diagnostic approach to acute and chronic lateral ligamentous ankle injuries. Conservative intervention and treatment of grade I-III and chronic, recurrent sprains of the lateral ankle ligaments and appropriate rehabilitation guidelines are the topics of this article. We review the use and benefit of different modalities and external supports and outline our five-phase intervention program of rehabilitation based on the histopathogenesis of ligament healing. We discuss the expected timing of recovery of the acute injury as well as the management of chronic, recurrent ankle sprains. Treatment of acute ankle sprains depends on the severity of the injury. Conservative therapy has been found to be uniformly effective in treating grade I and II ankle sprains. Some controversy exists regarding the appropriate treatment of grade III injuries, particularly in high-level athletes. Our belief is that the majority of these patients may also be treated well with conservative management. Other options for the management of grade III sprains will be briefly discussed at the end of this article.

View details for Web of Science ID 000081388800005

View details for PubMedID 10416545

Lateral ankle sprains: a comprehensive review - Part 1: etiology, pathoanatomy, histopathogenesis, and diagnosis MEDICINE AND SCIENCE IN SPORTS AND EXERCISE Safran, M. R., Benedetti, R. S., Bartolozzi, A. R., Mandelbaum, B. R. 1999; 31 (7): S429-S437


Ankle sprains are among the most common injuries sustained by athletes and seen by sports medicine physicians. Despite their prevalence in society, ankle sprains still remain a difficult diagnostic and therapeutic challenge in the athlete, as well as in society in general. The purpose of this section of our two-part study is to review scope of the problem, the anatomy and biomechanics of the lateral ankle ligaments, review the pathoanatomical correlates of lateral ankle sprains, the histopathogenesis of ligament healing, and define the mechanisms of injury to understand the basis of our diagnostic approach to the patient with this common acute and chronic injury. We extensively review the diagnostic evaluation including historical information and physical examination, as well as options for supplementary radiographic examination. We further discuss the differential diagnosis of the patient with recurrent instability symptoms. This will also serve as the foundation for part two of our study, which is to understand the rationale for our treatment approach for this common problem.

View details for Web of Science ID 000081388800004

View details for PubMedID 10416544

The effects of joint position and direction of joint motion on proprioceptive sensibility in anterior cruciate ligament-deficient athletes AMERICAN JOURNAL OF SPORTS MEDICINE Borsa, P. A., Lephart, S. M., Irrgang, J. J., Safran, M. R., Fu, F. H. 1997; 25 (3): 336-340


We studied a group of anterior cruciate ligament-deficient athletes to identify whether joint position and direction of joint motion have a significant effect on proprioception. Twenty-nine anterior cruciate ligament-deficient athletes were tested for their threshold to detect passive motion at both 15 degrees and 45 degrees moving into the directions of both flexion and extension. The single-legged hop test was used to identify function in the deficient limb. Results demonstrated statistically significant deficits in threshold to detect passive motion for the deficient limb at 15 degrees moving into extension. For the deficient limb, threshold to detect passive motion was significantly more sensitive moving into extension than flexion at a starting angle of 15 degrees; at a starting angle of 15 degrees moving into extension threshold was significantly more sensitive than at a starting angle of 45 degrees moving into extension. We conclude that in deficient limbs proprioception is significantly more sensitive in the end ranges of knee extension (15 degrees) and is significantly more sensitive moving into the direction of extension. To effectively restore reflex stabilization of the lower limb we recommend a rehabilitation program emphasizing performance-based, weightbearing, closed kinetic chain exercise for the muscle groups that act on the knee joint.

View details for Web of Science ID A1997XA52700011

View details for PubMedID 9167813

Technical considerations of revision anterior cruciate ligament surgery CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Safran, M. R., Harner, C. D. 1996: 50-64


Revision anterior cruciate ligament surgery will become more common as the number of primary anterior cruciate ligament reconstructions increases. Also contributing to this increase are those patients who had anterior cruciate ligament reconstruction using synthetic ligaments and other nonanatomic techniques that are no longer used. Preoperative planning is imperative to a successful outcome. This begins with determining the primary, and often times secondary, mechanism of failure for each patient. The determination of the etiology of failure is the first step in a carefully constructed preoperative plan, including the type of revision, skin incision, graft removal, hardware removal, tunnel placement, graft selection, graft fixation, and rehabilitation. The precise preoperative plan should have enough flexibility to accommodate unanticipated findings in the operating room. Rehabilitation protocols must be designed specifically for the revision surgery patient and be flexible enough to accommodate changes based on surgical findings and techniques. Finally, the importance of counseling the patient preoperatively regarding the potential results which, in general, are somewhat less satisfactory than with most primary reconstructions, must be emphasized. However, with proper planning, attention to detail, and adherence to basic principles of anterior cruciate ligament reconstruction, revision anterior cruciate ligament surgery can provide a satisfying solution to difficult knee instability cases.

View details for Web of Science ID A1996UD41500007

View details for PubMedID 8998899

Graft selection in knee surgery. Current concepts. The American journal of knee surgery Safran, M. R. 1995; 8 (4): 168-180


Recent advances in the understanding of knee mechanics and pathomechanics, in addition to newer techniques and instrumentation, have resulted in broadened indications for knee ligament surgery. Further, revision knee ligament or tendon surgery and delayed primary reconstruction are becoming more common as well. With the poor results of primary suture repair of the cruciate ligaments and the lateral collateral ligament, other graft sources often must be used. As a result, one must be familiar with the advantages and disadvantages of the different graft options available to the knee surgeon. This article discusses the current concepts regarding the advantages and disadvantages of the different graft options available to the knee surgeon.

View details for PubMedID 8590129



Athletes expose their elbows to significantly high forces, in addition to multiple repetitive motions. Athletic injuries about the elbow include ligamentous, tendon, articular, and nerve injuries. The proper diagnosis requires a thorough knowledge of the anatomy, pathomechanics, and physical findings associated with these injuries. Treatment entails a methodical progression from nonoperative to operative intervention.

View details for Web of Science ID A1995RK06000007

View details for PubMedID 7609961



There are many causes of knee pain in the athlete. Clearly, common things, such as meniscal tears, ligament sprains, contusions, and patellofemoral dysfunction, are common. The infrequency of other entities, however, should not make the physician complacent. A thorough history and physical examination will, in most cases, elicit inconsistencies in the occasional athlete presenting with one of these uncommon causes of knee pain (Table 1). Diagnosing these uncommon causes, when they do present to the health care provider, allows for early and correct treatment with a more rapid return to sports.

View details for Web of Science ID A1995RK06000011

View details for PubMedID 7609965



Automotive airbag technology has reduced the number of injuries and fatalities resulting from motor vehicle crashes. With the increasingly frequent application of this safety feature in automobiles, recent reports of airbag-associated injuries have emerged, including ocular and non-lethal cardiac trauma. We report three cases of airbag-related upper extremity injuries seen at a level-I trauma center over a 6-month period. A heightened awareness of this type of injury in patients injured in motor vehicle crashes with airbag deployment is recommended. The awareness, identification, and management of these high energy injuries will take on added meaning as the airbag technology becomes universally applied.

View details for Web of Science ID A1995RD56300018

View details for PubMedID 7723098



We performed a retrospective review of a series of knee arthroscopic procedures that were completed using local, general, or regional anesthesia to evaluate the efficacy of these anesthetic techniques. Operative time, complications or failures, procedures successfully performed, recovery room time and postoperative stay, and patient satisfaction were recorded. Local anesthesia with intravenous sedation compared favorably with the other techniques: operative time was not increased, a large variety of operative procedures were successfully completed, recovery time was significantly shortened, and patient satisfaction remained high. This technique offers several advantages over other types of anesthesia for knee arthroscopy, including improved cost effectiveness.

View details for Web of Science ID A1995QC08700008

View details for PubMedID 7726350

Revision ACL surgery: Technique and results utilizing allografts 1994 Instructional Course Lectures, at the 61st Annual Meeting of the American-Academy-of-Orthopaedic-Surgeons Safran, M. R., Harner, C. D. AMER ACAD ORTHOPAEDIC SURGEONS. 1995: 407–415

View details for Web of Science ID A1995BH44U00036

View details for PubMedID 7797879



Elbow injuries are becoming more common as increasing numbers of people participate in throwing and racquet sports. The understanding and treatment of elbow injuries is becoming more sophisticated in conjunction with better noninvasive and invasive diagnostic techniques. The majority of injuries to the elbow in the athlete are chronic, overuse injuries. These injuries are the result of repetitive intrinsic or extrinsic overload, or both, resulting in microrupture of soft tissue such as ligament or tendon. In children, apophyses, being the weakest link in the immature musculoskeletal system, are susceptible to stress injuries. Elbow injuries are most commonly caused by valgus stress, from throwing or axial compression, resulting in increased force absorbed by the medial elbow. With repetitive valgus stress, patients may develop chondromalacia, loose bodies in the posterior or lateral compartments, injury to the ulnar collateral ligament, myotendinous injury to the flexor-pronator muscle group, osteochondritis dissecans, or ulnar neuritis. The purpose of this paper is to (1) define the significance of elbow injuries in athletics, (2) review the anatomy and biomechanics of the elbow, and (3) discuss the prevention and treatment of elbow injuries.

View details for Web of Science ID A1995QB44700039

View details for PubMedID 7641448

DORSAL DEFECT OF THE PATELLA JOURNAL OF PEDIATRIC ORTHOPAEDICS Safran, M. R., McDonough, P., Seeger, L., Gold, R., Oppenheim, W. L. 1994; 14 (5): 603-607


Dorsal defect of the patella is a benign subchondral lesion of unknown etiology, located in the superolateral region of the patella. The lesion presents with a characteristic radiographic appearance consisting of a rounded focus of radiolucency surrounded by a sclerotic margin. Although often an incidental finding on knee radiographs, it occasionally may be symptomatic. It occurs in males and females with equal frequency, is bilateral in up to one third of individuals, and is most frequently found in adolescents. This report describes a series of eight such lesions in five patients.

View details for Web of Science ID A1994PC79600009

View details for PubMedID 7962501

151 endoprosthetic reconstructions for patients with primary tumors involving bone. Contemporary orthopaedics Safran, M. R., KODY, M. H., Namba, R. S., Larson, K. R., Kabo, J. M., Dorey, F. J., Eilber, F. R., Eckardt, J. J. 1994; 29 (1): 15-25


As part of the UCLA limb salvage program, 151 patients received 151 endoprostheses for primary tumors involving bone. Follow-up of all patients was to death (56), revision (21), or a minimum two years for the 74 additional survivors (range: 24-114 months; mean: 52 months). Endoprosthetic replacements were of the distal femur (81), proximal femur (19), proximal humerus (13), proximal tibia (11), scapula (11), total femur (8), total humerus (4), intercalary prostheses (2), and one each of the distal humerus and the pelvis. There were three soft tissue sarcomas, five benign bone lesions, and 143 primary malignant tumors of bone. MSTS function was good-excellent in 78%. There were 64 local complications in 55 patients (36%). Mechanical failure occurred in 24 patients (15.9%), local recurrence occurred in ten (6.6%), minor wound healing problems in nine (5.9%), and infection in eight (5.3%). Few systemic complications were reported. Function appeared to be location dependent. All of the 29 patients with benign or low grade malignant tumors (parosteal, IA, IB) have survived. Of the 116 patients with stage IIA and IIB disease, 59% survived three years, and a Kaplan-Meier analysis projects that 56% are expected to survive at five years. Only 17 (11%) of these 151 endoprostheses have been revised; an additional four (3%) eventually came to amputation. The Kaplan-Meier analysis revealed that 91% of the prostheses survived three years and 83% survived five years. The Cox Proportional Hazards model revealed that for patients with stage IIA and IIB disease, the risk of death is four times the risk of the need for revision at five years. Although endoprosthetic reconstructions have their own unique complications, they have proven durable in this series of patients. Local problems usually can be managed without amputation, and patient satisfaction is high.

View details for PubMedID 10172089



The effect of a single injection of unpreserved blood on joint stiffness and on synovial and cartilage histomorphology in the ankle joints of rabbits was determined at ten and 28 days after injection. The same volume of saline was placed in the contralateral ankle for comparison. After ten days, the hemarthrosis ankle was stiffer than the control ankle (p < 0.027), whereas at 28 days there was no statistical difference in stiffness between the hemarthrosis and control ankles, regardless of whether the limbs had been immobilized. Also after ten days, the hemarthrosis ankles had varying amounts of clotted blood, darkened articular cartilage, hypertrophic synovium with reactive blood vessels, and macrophages containing heme. The gross and histologic appearance of the saline ankles was normal. After 28 days, there were no differences in gross or microscopic appearance between the two ankles of the caged or immobilized rabbits. All ankles exhibited retreating inflammatory response in the synovium and mild synovial thickening. Acute hemarthrosis, unassociated with fracture or discernible joint injury, caused only transient changes in joint stiffness and synovial histology. These results indicate that the presence of blood in an otherwise grossly uninjured joint should not lead to ultimate compromise in cartilage integrity or joint function. Therapeutic arthrocentesis for acute posttraumatic hemarthrosis does not appear to be necessary for the prevention of permanent problems.

View details for Web of Science ID A1994NP39100037

View details for PubMedID 8194245

Precision-fit surface hemiarthroplasty for femoral head osteonecrosis. Long-term results. journal of bone and joint surgery. British volume Amstutz, H. C., Grigoris, P., Safran, M. R., Grecula, M. J., Campbell, P. A., Schmalzried, T. P. 1994; 76 (3): 423-427


Cemented Ti-6Al-4V components were used to resurface ten femoral heads in nine young adult patients with osteonecrosis of the femoral head (average age 32 years; range 20 to 51). There were eight hips at Ficat stage III and two at stage IV. Five hips have maintained satisfactory function for an average period of 11.2 years (10 to 12.2) with no radiographic evidence of component loosening or osteolysis; five have been revised after an average period of 7.8 years (3.3 to 10.3) for pain caused by deterioration of the acetabular cartilage. No component required revision for loosening and the specimens retrieved at revision showed no evidence of osteolysis despite burnishing of the titanium bearing surface and the presence of particulate titanium debris in the tissues.

View details for PubMedID 8175846



Periarticular long bone fractures usually result in soft-tissue swelling because of edema and hemorrhage, as well as progressive, often permanent joint stiffness. The authors evaluated the effects of chlorothiazide, a commonly used diuretic, and acetazolamide, a weaker diuretic with a different mechanism of action, on joint stiffness and swelling using an established rabbit hindlimb model. Bilateral distal tibial fractures were produced in 30 adolescent New Zealand white rabbits. Twelve rabbits served as age-matched controls and received no treatment, 11 were treated with chlorothiazide, and seven were treated with acetazolamide, each for five days at doses adjusted for body weight but equivalent to human dosing. Eleven limbs were excluded from study because of fracture angulation in excess of 10 degrees. The mean stiffness ratios, comparing preoperative stiffness with stiffness at the end of the three-week study period, for diuretic-treated rabbits were significantly less than those in the control rabbits; there was no difference between the two treated groups. The total swelling and time to peak swelling did not differ among the three groups; however, peak swelling was least in the chlorothiazide group, the strong diuretic, when compared with the control and acetazolamide groups. The marked effect of diuretics on joint stiffness and their minimal effect on limb swelling were unexpected results and, taken in conjunction with previous treatment modalities tested in this model, indicate a complex, still poorly understood sequence of events leading to joint stiffness after periarticular injury.

View details for Web of Science ID A1994NL07400043

View details for PubMedID 8168315



Although compartment syndromes of the forearm are infrequently encountered, they are well described in the literature. Forearm compartment syndrome uncommonly occurs after percutaneous arterial blood sampling and is usually associated with anticoagulant therapy. Our review of the English literature revealed no other cases of forearm compartment syndrome after arterial blood sampling in patients with bleeding diathesis due to chronic renal failure. This article discusses a 30-year-old woman with Good-pasture's syndrome who developed a compartment syndrome after a brachial artery blood gas. The cause, diagnosis, and treatment of compartment syndrome and uremic bleeding, as well as a review of the literature, are discussed.

View details for Web of Science ID A1994NM10900017

View details for PubMedID 8060080



The mainstay of local control of primary bone malignancies in the skeletally immature has been amputation or, in selected cases, rotationplasty. The development of expandable endoprostheses has permitted an alternative approach for local control in the growing child. Between January 1985 and December 1987, 12 skeletally immature patients with primary malignant bone tumors were treated with extremity reconstruction with cemented custom-expandable endoprostheses after wide resection of their lesions. All patients were observed until death (four) or revision (two) with a minimum two-year follow-up period for the survivors (average, 3.1 years). Seven patients have undergone a total of 11 expansions and one patient was lengthened with a revision-expandable prosthesis. Four patients have not needed expansion. Eight patients have had a total of ten complications. Seven of the ten complications (70%) were prosthesis related and associated with failure of the expansion mechanism. The Musculoskeletal Tumor Society (MSTS) overall rating was good to excellent in seven patients (58%), fair in three (25%), and poor in two (17%). In five distal femoral arthroplasties and one total femoral arthroplasty where the tibial bearing component was cemented through the physis, tibial and epiphyseal growth was observed to be normal and equal to the nonoperative side. This suggests that partial central epiphyseal and physeal ablation does not cause physeal arrest. Although the high rate of expansion mechanism failure necessitates redesign, preliminary results suggest that expandable endoprostheses do offer an alternative to amputation and rotationplasty as a means of local control and extremity reconstruction in children with primary malignant bone tumors.

View details for Web of Science ID A1993ML67800032

View details for PubMedID 8242930

Continued growth of the proximal part of the tibia after prosthetic reconstruction of the skeletally immature knee. Estimation of the minimum growth force in vivo in humans. journal of bone and joint surgery. American volume Safran, M. R., Eckardt, J. J., Kabo, J. M., Oppenheim, W. L. 1992; 74 (8): 1172-1179


We studied five skeletally immature patients who had a cemented endoprosthetic replacement involving the proximal part of the tibia because of a malignant tumor. In each patient, the cement-column fractured, allowing additional physeal growth. With plain radiographs and scanograms, we determined the cross-sectional areas of the physes, the cement-mantle, and the tibial component. Using the known tensile strength of polymethylmethacrylate cement, we then calculated the minimum force that the growth plates must have overcome to fracture the cement. This averaged 584 newtons per square centimeter. This observation of continued tibial growth after partial physeal ablation with a cemented prosthesis in skeletally immature patients presented a unique opportunity to estimate the force generated in the human physis during growth.

View details for PubMedID 1400545

WARM-UP AND MUSCULAR INJURY PREVENTION AN UPDATE SPORTS MEDICINE Safran, M. R., Seaber, A. V., Garrett, W. E. 1989; 8 (4): 239-249


Musculotendinous injuries are responsible for a significant proportion of injuries incurred by athletes. Many of these injuries are preventable. Importantly, musculotendinous injuries have a high incidence of recurrence. Thus, muscle injury prevention is advocated by coaches and trainers. Yet, most of the recommendations for muscle injury prevention are attempted by athletes and taught by coaches without supporting scientific evidence. This paper reviews the mechanics of muscular injury, associated and predisposing factors, and methods of prevention with a review of the supporting research and rationale for these methods with an emphasis on warm-up, stretching and strengthening. Muscles that are capable of producing a greater force, a faster contraction speed and subjected to a greater stretch are more likely to become injured. Many factors have been associated with muscular injury. From current research, some conclusions and recommendations for muscle injury prevention can be made. Overall and muscular conditioning and nutrition are important. Proper training and balanced strengthening are key factors in prevention of musculotendinous injuries as well. Warm-up and stretching are essential to preventing muscle injuries by increasing the elasticity of muscles and smoothing muscular contractions. Improper or excessive stretching and warming up can, however, predispose to muscle injury. Much research is still needed in this important aspect of sports medicine.

View details for Web of Science ID A1989AU97100004

View details for PubMedID 2692118



This study is an attempt to provide biomechanical support for the athletic practice of warming up prior to an exercise task to reduce the incidence of injury. Tears in isometrically preconditioned (stimulated before stretching) muscle were compared to tears in control (nonstimulated) muscle by examining four parameters: 1) force and 2) change of length required to tear the muscle, 3) site of failure, and 4) length-tension deformation. The tibialis anterior (TA), the extensor digitorum longus (EDL), and flexor digitorum longus (EDL) muscles from both hindlimbs of rabbits comprised our experimental model. Isometrically preconditioned TA (P less than 0.001), EDL (P less than 0.005), and FDL (P less than 0.01) muscles required more force to fail than their contralateral controls. Preconditioned TA (P less than 0.05), EDL (P less than 0.001), and FDL (P less than 0.01) muscles also stretched to a greater length from rest before failing than their nonpreconditioned controls. The site of failure in all of the muscles was the musculotendinous junction; thus, the site of failure was not altered by condition. The length-tension deformation curves for all three muscle types showed that in every case the preconditioned muscles attained a lesser force at each given increase in length before failure, showing a relative increase in elasticity, although only the EDL showed a statistically significant difference. From our data, it may be inferred that physiologic warming (isometric preconditioning) is of benefit in preventing muscular injury by increasing the and length to failure and elasticity of the muscle-tendon unit.

View details for Web of Science ID A1988T693500006

View details for PubMedID 3377095



We compared the biomechanical properties of passive and stimulated muscle rapidly lengthened to failure in an experimental animal model. The mechanical parameters compared were force to tear, change in length to tear, site of failure, and energy absorbed by the muscle-tendon unit before failure. Paired comparisons were made between 1) muscles stimulated at 64 Hz (tetanic stimulation) and passive (no stimulation) muscles, 2) muscles stimulated at 16 Hz (wave-summated stimulation) and passive muscles, and 3) muscles stimulated at 64 Hz and at 16 Hz. Both tetanically stimulated and wave-summation contracted muscles required a greater force to tear (at 64 Hz, 12.86 N more, P less than 0.0004; and at 16 Hz, 17.79 N more, P less than 0.003) than their nonstimulated controls, while there was no statistical difference in failure force between muscles stimulated at 16 Hz and 64 Hz. The energy absorbed was statistically greater for the stimulated muscles than for the passive muscles in Groups 1 and 2 (at 64 Hz, 100% more, P less than 0.0003; and 16 Hz, 88% more, P less than 0.0002). In Group 3, the tetanically contracted muscle-tendon units absorbed 18% more energy than the wave-summated stimulated muscles (P less than 0.01). All muscles tore at the distal musculotendinous junction, and there was no difference in the length increase at tear between muscles in each group. These findings may lead to enhanced understanding of the mechanism and physiology of muscle strain injuries.

View details for Web of Science ID A1987N199900004

View details for PubMedID 3674268