Eric M. Berkson

Microfracture for osteochondral lesions of the ankle: outcome analysis and outcome predictors of 105 cases.

PURPOSE The purpose of this study was to identify outcomes and outcome predictors of arthroscopic debridement with osteochondral bone stimulation (microfracture) for osteochondral lesions of the ankle. METHODS One hundred five consecutive patients with osteochondral lesions of the ankle who underwent ankle arthroscopy with microfracture were prospectively followed up for a mean of 31.6 +/- 12.1 months. Study patients were evaluated at 6 weeks, 3 months, 6 months, 12 months, and annually after surgery. Assessments via a visual analog scale for pain during daily activities and sport activity, the Roles and Maudsley score, and the American Orthopaedic Foot & Ankle Society ankle and hindfoot scoring system were obtained at each visit. Outcome predictors were analyzed by logistic regression model. RESULTS There were no failures of treatment with lesions smaller than 15 mm. In contrast, only 1 patient met the criteria for success in the group of lesions greater than 15 mm. Statistical analysis revealed that increasing age, higher body mass index, history of trauma, and presence of osteophytes negatively affected outcome. The presence of instability and the presence of anterolateral soft-tissue scar were correlated with a successful outcome. CONCLUSIONS This study found a strong correlation between lesion size and success across its entire population. For lesions smaller than 15 mm, regardless of location, excellent results were obtained. In addition, increasing age, higher body mass index, history of trauma, and presence of osteophytes negatively affect outcome. The presence of instability and anterolateral soft-tissue scar correlated with a successful outcome. LEVEL OF EVIDENCE Level IV, prognostic case series, prognostic study.

High-energy tibial plateau fractures.

Abstract The severity of a tibial plateau fracture and the complexity of its treatment depend on the energy imparted to the limb. Low‐energy injuries typically cause unilateral depression‐type fractures, whereas high‐energy injuries can lead to comminuted fractures with significant osseous, soft‐tissue, and neurovascular injury. Evaluation includes appropriate radiographs and careful clinical assessment of the soft‐tissue envelope. Treatment is directed at safeguarding tissue vascularity and emphasizes restoration of joint congruity and the mechanical axis of the limb. Temporary joint‐spanning external fixation facilitates soft‐tissue recovery, whereas minimally invasive techniques and anatomically contoured plates can limit damage to the soft tissues and provide stable fixation. Alternatively, the use of limited internal fixation and definitive external fixation can minimize soft‐tissue disruption, avoid complications, and allow fracture union. Complications, including infection, loss of fixation, and malalignment, are best avoided by following these biologically respectful treatment principles.

Problems with cementless total knee arthroplasty at 11 years followup.

One hundred two patients with 131 consecutive cementless total knee arthroplasties that retained the posterior cruciate ligament were followed up prospectively. The average age of the patients was 58 years (range, 32–75 years). The mean followup on the surviving knee arthroplasties was 11 years (range, 7–16 years). The patellar component was metal-backed in the first 112 (85%) knees, cementless all-polyethylene in the last 17 (13%) knees, and two knees had a prior patellectomy. Forty-four metal-backed patellar components (48%) were revised; nine were loose, and 35 had polyethylene wear through. Thirteen femoral components (12%) were revised because of femoral abrasion from a failed metal-backed patellar component. No other femoral component was revised, loose, or had osteolysis develop. Nine (8%) tibial components had failure of ingrowth; eight have been revised. Partial radiolucencies occurred in 53% of the tibias. Thirteen (12%) small osteolytic lesions developed, all around screws or screw holes in the tibial components. At an average of 11 years followup, cementless fixation yielded mixed results: cementless femoral fixation was excellent and metal-backed patellar components had a 48% patellar revision rate. Cementless tibial components had an 8% aseptic loosening rate and a 12% incidence of small osteolytic lesions. Based on these results, the authors have abandoned cementless fixation in total knee arthroplasty.

Comparison of two and three-dimensional computerized polyethylene wear analysis after total hip arthroplasty

Background: The accurate determination of acetabular polyethylene wear in vivo is necessary to assess the clinical performance of the bearing surfaces of total hip replacements. Our objective in this study was to determine the clinical performance of two and three-dimensional computerized wear analysis and to assess the implications of this performance on requirements for patient enrollment in studies designed to detect wear of total hip prostheses.Methods: Two and three-dimensional digital computerized analyses of acetabular polyethylene wear were performed on 153 hips in 140 patients. The acetabular components consisted of a polyethylene insert in a titanium shell, articulating with a 28-mm cobalt-chromium femoral component. The average duration of radiographic follow-up was 8.4 years. The correlation coefficient for two-dimensional versus three-dimensional analysis was calculated, as was the difference between the wear detected by the two techniques. The same observer analyzed each image twice, allowing an assessment of the repeatability of the two-dimensional and three-dimensional analyses. The impact of the clinical performance of each technique on the sample size needed for adequate power in prospective studies was evaluated.Results: There was a high correlation between two-dimensional and three-dimensional wear analysis (r 2 = 0.933). In thirty-one (5.2%) of 595 observations, the wear values derived with the two-dimensional and three-dimensional techniques were not consistent. Logistic regression demonstrated that acetabular anteversion had a significant effect on the likelihood of such inconsistency occurring. The two-dimensional technique detected 90.1% of the total linear wear subsequently detected by the three-dimensional analysis. The average wear value was 1.09 mm as detected by two-dimensional analysis and 1.21 mm as detected by three-dimensional analysis. The two-dimensional technique was four times more repeatable than the three-dimensional technique. Power analysis indicated that up to 1.4 times more patients need to be enrolled if the three-dimensional technique is used for wear analysis.Conclusions: While three-dimensional analysis detected 10% more wear, its repeatability was four times worse than that of the two-dimensional technique and, as a consequence, patient enrollment requirements for wear detection were higher. The poor quality of the lateral radiographs contributed to the decrease in the repeatability of the three-dimensional analysis. Three-dimensional analysis may be useful for highly anteverted cups, but the limited improvement in wear detection achieved with that technique, coupled with its inferior repeatability, limits its clinical value.Level of Evidence: Diagnostic study, Level IV-2 (poor reference standard). See Instructions to Authors for a complete description of levels of evidence.

A Distributed Wearable, Wireless Sensor System for Evaluating Professional Baseball Pitchers and Batters

This paper introduces a compact, wireless, wearable system that measures signals indicative of forces, torques and other descriptive and evaluative features that the human body undergoes during bursts of extreme physical activity (such as during athletic performance). Standard approaches leverage high-speed camera systems, which need significant infrastructure and provide limited update rates and dynamic accuracy. This project uses 6 degree-of freedom inertial measurement units worn on various segments of an athlete’s body to directly make these dynamic measurements. A combination of low and high range sensors enables sensitivity for both slow and fast motion, and the addition of a compass helps in tracking joint angles. Data from the battery-powered nodes is acquired using a custom wireless protocol over an RF link and analyzed offline. Several professional pitchers and batters were instrumented with the system and data was gathered over many pitches and swings. We show some biomechanically descriptive parameters extracted from this data, and highlight ongoing work and system improvements

Extracorporeal shock wave for chronic proximal plantar fasciitis: 225 patients with results and outcome predictors.

UNLABELLED Plantar fasciitis can be a chronic and disabling cause of foot pain in the adult population. For refractory cases, extracorporeal shock wave therapy (ESWT) has been proposed as therapeutic option to avoid the morbidity of surgery. We hypothesized that the success of extracorporeal shock wave therapy in patients with chronic plantar fasciitis is affected by patient-related factors. A retrospective review of 225 patients (246 feet) who underwent consecutive ESWT treatment by a single physician at our institution between July 2002 and July 2004 was performed. Subjects were included only if they had plantar fasciitis for more than 6 months and failure to response to at least 5 conservative modalities. Patients were evaluated prospectively with health questionnaires, Roles and Maudsley scores, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot scores at regular intervals. Follow-up was 30.2 +/- 8.7 months post procedure. Multivariable analysis was performed to assess factors leading to successful outcomes. Success rates of 70.7% at 3 months and 77.2% at 12 months were noted in this population. Previous cortisone injections, body mass index, duration of symptoms, presence of bilateral symptoms, and plantar fascia thickness did not influence the outcome of ESWT. The presence of diabetes mellitus, psychological issues, and older age were found to negatively influence ESWT outcome. Whereas many factors have been implicated in the development of plantar fasciitis, only diabetes mellitus, psychological issues, and age were found to negatively influence ESWT outcome. LEVEL OF CLINICAL EVIDENCE 2.

The Effect of Cyclic Loading on Rotated Bone-Tendon-Bone Anterior Cruciate Ligament Graft Constructs

Background Single-incision anterior cruciate ligament reconstruction with a bone–patellar tendon–bone construct is commonly performed with 180° rotation of the graft. It has been hypothesized that further rotation of the graft to 540° can effectively shorten the graft to address graft length–tunnel mismatch. Initial biomechanical failure characteristics of rotated constructs have been reported, but cyclic loading of tendons has not been performed. Hypothesis Graft rotation affects the biomechanical properties of the construct. Study Design Controlled laboratory study. Methods Thirty-five bone–patellar tendon–bone composite porcine right knee specimens were randomized into 3 groups and were externally rotated to 0°, 180°, or 540°. Each group was then cyclically loaded in an artificial synovial fluid medium between 50 and 250 N for 5000 cycles, loaded between 50 and 500 N for an additional 5000 cycles, and finally subjected to load-to-failure testing. Results Graft rotation shortened constructs by 1.7 ± 0.8 mm at 180° of rotation and 7.6 ± 2.0 mm at 540° of rotation (P < .01). There was a statistically significant increase in strain during cyclic loading at 540°. No significant differences in maximum load, yield stress, yield strain, or modulus of elasticity were detected in single-cycle load-to-failure testing after cyclic loading. Conclusion Rotation of bone–patellar tendon–bone constructs to 540° predictably shortens the effective graft length at the expense of increased strain with cyclic loading at stresses equivalent to walking and running. Clinical Relevance Although rotation to 540° potentially addresses graft length–tunnel mismatch, further clinical evaluation is required to evaluate the impact of increased strain on knee laxity and to determine the effects of physiologic loading of rotated bone–patellar tendon–bone constructs in vivo.

Shoulder Instability in Professional Football Players

Background: Shoulder instability is a common problem in American football players entering the National Football League (NFL). Treatment options include nonoperative and surgical stabilization. Purpose: This study evaluated how the method of treatment of pre-NFL shoulder instability affects the rate of recurrence and the time elapsed until recurrence in players on 1 NFL team. Design: Retrospective cohort. Methods: Medical records from 1980 to 2008 for 1 NFL team were reviewed. There were 328 players included in the study who started their career on the team and remained on the team for at least 2 years (mean, 3.9 years; range, 2-14 years). The history of instability prior to entering the NFL and the method of treatment were collected. Data on the occurrence of instability while in the NFL were recorded to determine the rate and timing of recurrence. Results: Thirty-one players (9.5%) had a history of instability prior to entering the NFL. Of the 297 players with no history of instability, 39 (13.1%) had a primary event at a mean of 18.4 ± 22.2 months (range, 0-102 months) after joining the team. In the group of players with prior instability treated with surgical stabilization, there was no statistical difference in the rate of recurrence (10.5%) or the timing to the instability episode (mean, 26 months) compared with players with no history of instability. Twelve players had shoulder instability treated nonoperatively prior to the NFL. Five of these players (41.7%) had recurrent instability at a mean of 4.4 ± 7.0 months (range, 0-16 months). The patients treated nonoperatively had a significantly higher rate of recurrence (P = 0.02) and an earlier time of recurrence (P = 0.04). The rate of contralateral instability was 25.8%, occurring at a mean of 8.6 months. Conclusion: Recurrent shoulder instability is more common in NFL players with a history of nonoperative treatment. Surgical stabilization appears to restore the rate and timing of instability to that of players with no prior history of instability.

Athletic Assistive Technology for Persons with Physical Conditions Affecting Mobility

ABSTRACT Recent advances in technology have allowed athletes with physical conditions to perform at increasingly high levels. After the ruling that one such athlete had an advantage over “able-bodied” athletes before the 2008 Olympics, many question whether these technological advances have even augmented athletic abilities. Although much progress has been achieved, technology for “disabled” athletes must be far advanced to allow them to reach and surpass the ability level of able-bodied athletes. Here, we review the current state of assistive devices created to assist athletes with physical conditions affecting their mobility. We form a quantitative comparison between athletes with and without physical conditions, lay out recent advancements in the development of sports-related assistive devices, and discuss the implications of these devices. Using the Paralympics as a guide, this work serves as an overview of the current state of assistive technology for athletes with mobility conditions and a tool for future researchers attempting to bridge the gap between athletes with and without physical conditions.

Injuries observed in a prospective transition from traditional to minimalist footwear: correlation of high impact transient forces and lower injury severity

ABSTRACT Objectives: Minimalist running is increasing in popularity based upon a concept that it can reduce impact forces and decrease injury rates. The purpose of this investigation is to identify the rate and severity of injuries in runners transitioning from traditional to minimalist footwear. The secondary aims were to identify factors correlated with injuries. Methods: Fourteen habitually shod (traditional running shoes) participants were enrolled for this prospective study investigating injury prevalence during transition from traditional running shoes to 5-toed minimalist shoes. Participants were uninjured, aged between 22-41 years, and ran at least twenty kilometers per week in traditional running shoes. Participants were given industry recommended guidelines for transition to minimalist footwear and fit with a 5-toed minimalist running shoe. They completed weekly logs for identification of injury, pain using Visual Analogue Scale (VAS), injury location, and severity. Foot strike pattern and impact forces were collected using 3D motion analysis at baseline, 4 weeks, and 12 weeks. Injuries were scored according to a modified Running Injury Severity Score (RISS). Results: Fourteen runners completed weekly training and injury logs over an average of 30 weeks. Twelve of 14 (86%) runners sustained injuries. Average injury onset was 6 weeks (range 1–27 weeks). Average weekly mileage of 23.9 miles/week prior to transition declined to 18.3 miles/week after the transition. The magnitude of the baseline impact transient peak in traditional shoes and in minimalist shoes negatively correlated with RISS scores (r = −0.45, p = 0.055 and r = −0.53, p = 0.026, respectively). Conclusion: High injury rates occurred during the transition from traditional to minimalist footwear. Non-compliance to transition guidelines and high injury rates suggest the need for improved education. High impact transient forces unexpectedly predicted lower modified RISS scores in this population.