Upper-extremity blood flow restriction: the proximal, distal, and contralateral effects-a randomized controlled trial.

BACKGROUND: Blood flow restriction (BFR) training with low weight is purported to induce similar physiological changes to high-weight regimens with the benefit of less tissue stress. We hypothesized that low-weight training with BFR would produce increased gains in strength and hypertrophy for muscle groups proximal, distal, and contralateral to tourniquet placement compared with low-weight training alone. METHODS: In this prospective, randomized controlled trial, healthy subjects were randomized into a 6-week low-weight training program either with or without BFR on 1 extremity. Outcome measures included limb circumference and strength. Comparisons were made between the BFR and non-BFR extremities, BFR and control groups, and non-BFR extremity and control groups. RESULTS: A total of 24 subjects (14 BFR and 10 control subjects) completed the protocol. Significantly greater gains were observed in dynamometric strength both proximal (shoulder scaption [30% greater], flexion [23%], and abduction [22%]) and distal (grip strength [13%]) to the tourniquet in the BFR limb compared with both the non-BFR extremity and the control group (P < .05). Arm and forearm circumferences significantly increased in the BFR limb compared with the non-BFR limb and control group (P = .01). The non-BFR extremity demonstrated greater grip strength than the control group (9%, P < .01). No adverse events were reported. CONCLUSION: Low-weight BFR training provided a greater increase in strength and hypertrophy in the upper-extremity proximal and distal muscle groups compared with the control group. The non-BFR extremity showed a significant increase in grip strength compared with the control group, indicating a potential systemic effect.

Proximal, Distal, and Contralateral Effects of Blood Flow Restriction Training on the Lower Extremities: A Randomized Controlled Trial.

BACKGROUND:: Blood flow restriction (BFR) training involves low-weight exercises performed under vascular occlusion via an inflatable cuff. For patients who cannot tolerate high-load exercises, BFR training reportedly provides the benefits of high-load regimens, with the advantage of less tissue and joint stress. HYPOTHESIS:: Low-load BFR training is safe and efficacious for strengthening muscle groups proximal, distal, and contralateral to tourniquet placement in the lower extremities. STUDY DESIGN:: Randomized controlled trial. LEVEL OF EVIDENCE:: Level 1. METHODS:: This was a randomized controlled trial of healthy participants completing a standardized 6-week course of BFR training. Patients were randomized to BFR training on 1 extremity or to a control group. Patients were excluded for cardiac, pulmonary, or hematologic disease; pregnancy; or previous surgery in the extremity. Data collected at baseline and completion included limb circumferences and strength testing. RESULTS:: The protocol was completed by 26 patients, providing 16 BFR and 10 control patients (mean patient age, 27 years; 62% female). A statistically greater increase in strength was seen proximal and distal to the BFR tourniquet when compared with both the nontourniquet extremity and the control group ( P < 0.05). Approximately twice the improvement was seen in the BFR group compared with controls. Isokinetic testing showed greater increases in knee extension peak torque (3% vs 11%), total work (6% vs 15%), and average power (4% vs 12%) for the BFR group ( P < 0.04). Limb circumference significantly increased in both the thigh (0.8% vs 3.5%) and the leg (0.4% vs 2.8%) compared with the control group ( P < 0.01). Additionally, a significant increase occurred in thigh girth (0.8% vs 2.3%) and knee extension strength (3% vs 8%) in the nontourniquet BFR extremity compared with the control group ( P < 0.05). There were no reported adverse events. CONCLUSION:: Low-load BFR training led to a greater increase in muscle strength and limb circumference. BFR training had similar strengthening effects on both proximal and distal muscle groups. Gains in the contralateral extremity may corroborate a systemic or crossover effect. CLINICAL RELEVANCE:: BFR training strengthens muscle groups proximal, distal, and contralateral to cuff placement. Patients undergoing therapy for various orthopaedic conditions may benefit from low-load BFR training with the advantage of less tissue stress.

The Development and Validation of a Subjective Assessment Tool for the Hip in the Athletic Population.

BACKGROUND: No validated functional assessments are available that are designed specifically to evaluate the performance and function of the athletic hip. Subsections of some validated outcome assessments address recreation, but a full assessment dedicated to athletic hip function does not exist. Current hip scoring systems may not be sensitive to subtle changes in performance and function in an athletic, younger population. HYPOTHESIS: The patient-athlete subjective scoring system developed in this study will be validated, reliable, and responsive in the evaluation of hip function in the athlete. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Based on the results of a pilot questionnaire administered to 18 athletic individuals, a final 10-item questionnaire was developed. Two hundred fifty competitive athletes from multiple sports completed the final questionnaire and 3 previously validated hip outcome assessments. Each athlete was self-assigned to 1 of 3 injury categories: (1) playing without hip/groin trouble; (2) playing, but with hip/groin trouble; and (3) not playing due to hip/groin trouble. The injury categories contained 196, 40, and 14 athletes, respectively. Correlations between the assessment scores and injury categories were measured. Responsiveness testing was performed in an additional group of 24 injured athletes, and their scores before and after intervention were compared. RESULTS: The Kerlan-Jobe Orthopaedic Clinic (KJOC) Athletic Hip Score showed high correlation with the modified Harris Hip Score, the Nonarthritic Hip Score, and the International Hip Outcome Tool. The new score stratified athletes by injury category, demonstrated responsiveness and accuracy, and varied appropriately with improvements in injury category after treatment of injuries. CONCLUSION: The new KJOC Athletic Hip Score is valid, reliable, and responsive for evaluation of the hip in an athletic population. The results support its use for the functional assessment of the hip in future studies.

The effect of a dynamic PCL brace on patellofemoral compartment pressures in PCL-and PCL/PLC-deficient knees.

BACKGROUND: The natural history of posterior cruciate ligament (PCL) deficiency includes the development of arthrosis in the patellofemoral joint (PFJ). The purpose of this biomechanical study was to evaluate the hypothesis that dynamic bracing reduces PFJ pressures in PCL- and combined PCL/posterolateral corner (PLC)-deficient knees. STUDY DESIGN: Controlled Laboratory Study. METHODS: Eight fresh frozen cadaveric knees with intact cruciate and collateral ligaments were included. PFJ pressures and force were measured using a pressure mapping system via a lateral arthrotomy at knee flexion angles of 30°, 60°, 90°, and 120° in intact, PCL-deficient, and PCL/PLC-deficient knees under a combined quadriceps/hamstrings load of 400 N/200 N. Testing was then repeated in PCL- and PCL/PLC-deficient knees after application of a dynamic PCL brace. RESULTS: Application of a dynamic PCL brace led to a reduction in peak PFJ pressures in PCL-deficient knees. In addition, the brace led to a significant reduction in peak pressures in PCL/PLC-deficient knees at 60°, 90°, and 120° of flexion. Application of the dynamic brace also led to a reduction in total PFJ force across all flexion angles for both PCL- and PCL/PLC-deficient knees. CONCLUSION: Dynamic bracing reduces PFJ pressures in PCL- and combined PCL/PLC-deficient knees, particularly at high degrees of knee flexion.

Influence of Bulk Microphysics Schemes upon Weather Research and Forecasting (WRF) Version 3.6.1 Nor'easter Simulations.

This study evaluated the impact of five, single- or double- moment bulk microphysics schemes (BMPSs) on Weather Research and Forecasting model (WRF) simulations of seven, intense winter time cyclones impacting the Mid-Atlantic United States. Five-day long WRF simulations were initialized roughly 24 hours prior to the onset of coastal cyclogenesis off the North Carolina coastline. In all, 35 model simulations (5 BMPSs and seven cases) were run and their associated microphysics-related storm properties (hydrometer mixing ratios, precipitation, and radar reflectivity) were evaluated against model analysis and available gridded radar and ground-based precipitation products. Inter-BMPS comparisons of column-integrated mixing ratios and mixing ratio profiles reveal little variability in non-frozen hydrometeor species due to their shared programming heritage, yet their assumptions concerning snow and graupel intercepts, ice supersaturation, snow and graupel density maps, and terminal velocities lead to considerable variability in both simulated frozen hydrometeor species and radar reflectivity. WRF-simulated precipitation fields exhibit minor spatio-temporal variability amongst BMPSs, yet their spatial extent is largely conserved. Compared to ground-based precipitation data, WRF-simulations demonstrate low-to-moderate (0.217-0.414) threat scores and a rainfall distribution shifted toward higher values. Finally, an analysis of WRF and gridded radar reflectivity data via contoured frequency with altitude (CFAD) diagrams reveals notable variability amongst BMPSs, where better performing schemes favored lower graupel mixing ratios and better underlying aggregation assumptions.

Validation of IMERG precipitation in Africa.

Our understanding of hydroclimatic processes in Africa has been hindered by the lack of in-situ precipitation measurements. Satellite-based observations, in particular, the TRMM Multi-Satellite Precipitation Analysis (TMPA) have been pivotal to filling this void. The recently-released Integrated Multi-satellitE Retrievals for GPM (IMERG) project aims to continue the legacy of its predecessor, TMPA, and provide higher resolution data. Here, we validate IMERG-V04A precipitation data using in-situ observations from the Trans-African Hydro-Meteorological Observatory (TAHMO) project. Various evaluation measures are examined over a select number of stations in West and East Africa. In addition, continent-wide comparisons are made between IMERG and TMPA. The results show that the performance of the satellite-based products varies by season, region and the evaluation statistics. Precipitation diurnal cycle is relatively better captured by IMERG than TMPA. Both products exhibit a better agreement with gauge data in East Africa and humid West Africa than in the Southern Sahel. However, a clear advantage for IMERG is not apparent in detecting the annual cycle. Although all gridded products used here reasonably capture the annual cycle, some differences are evident during the short rains in East Africa. Direct comparison between IMERG and TMPA over the entire continent reveals that the similarity between the two products is also regionally heterogeneous. Except for Zimbabwe and Madagascar, where both satellite-based observations present a good agreement, the two products generally have their largest differences over mountainous regions. IMERG seems to have achieved a reduction in the positive bias evident in TMPA over Lake Victoria.

Neuromuscular Evaluation With Single-Leg Squat Test at 6 Months After Anterior Cruciate Ligament Reconstruction.

BACKGROUND: Criteria for return to unrestricted activity after anterior cruciate ligament (ACL) reconstruction varies, with some using time after surgery as the sole criterion-most often at 6 months. Patients may have residual neuromuscular deficits, which may increase the risk of ACL injury. A single-leg squat test (SLST) can dynamically assess for many of these deficits prior to return to unrestricted activity. HYPOTHESIS: A significant number of patients will continue to exhibit neuromuscular deficits with SLST at 6 months after ACL reconstruction. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Patients using a standardized accelerated rehabilitation protocol at their 6-month follow-up after primary ACL reconstruction were enrolled. Evaluation included bilateral SLST, single-leg hop distance, hip abduction strength, and the subjective International Knee Documentation Committee (IKDC) score. RESULTS: Thirty-three patients were enrolled. Poor performance of the operative leg SLST was found in 15 of 33 patients (45%). Of those 15 patients, 7 (45%) had concomitant poor performance of the nonoperative leg compared with 2 of 18 patients (11%) in those who demonstrated good performance in the operative leg. The poor performers were significantly older (33.6 years) than the good performers (24.2 years) (P = .007). Those with poor performance demonstrated decreased hip abduction strength (17.6 kg operative leg vs 20.5 kg nonoperative leg) (P = .024), decreased single-leg hop distance (83.3 cm operative leg vs 112.3 cm nonoperative leg) (P = .036), and lower IKDC scores (67.9 vs 82.3) (P = .001). CONCLUSION: Nearly half of patients demonstrated persistent neuromuscular deficits on SLST at 6 months, which is when many patients return to unrestricted activity. Those with poor performance were of a significantly older age, decreased hip abduction strength, decreased single-leg hop distance, and lower IKDC subjective scores. CLINICAL RELEVANCE: The SLST can be used to identify neuromuscular risk factors for ACL rupture. Many patients at 6 months have persistent neuromuscular deficits on SLST. Caution should be used when using time alone to determine when patients can return to unrestricted activity.

Impact of fellowship training on clinical practice of orthopaedic sports medicine.

BACKGROUND: Approximately 90% of current orthopaedic graduates are engaging in fellowship training, with sports medicine being the most commonly chosen specialty. The purpose of this study was to evaluate the impact of fellowship training on clinical decision-making by fellowship-trained sports medicine surgeons. METHODS: A survey was designed to assess the importance of fellowship on common clinical decisions made in the nonoperative and surgical treatment of knee, shoulder, and elbow disorders. The survey also included questions for the respondents on their comfort level with a variety of routine and complex surgical procedures. The survey was sent to alumni of 113 orthopaedic sports medicine programs across the United States. RESULTS: Completed surveys were returned by 310 surgeons who had been in practice for an average of 9.0 years. They represented alumni of twenty-nine orthopaedic sports medicine fellowship programs across sixteen states. Fellowship was considered very important for surgical decision-making in the knee and shoulder. For nonoperative treatment, fellowship had a greater impact on shoulder disorders than on knee or elbow disorders. Fellowship was significantly more important than residency (p < 0.001) for determining preferred surgical equipment, implants, and braces. Among the surgical procedures assessed, respondents were least comfortable with the treatment of multi-ligamentous knee injuries, posterior cruciate ligament injuries, and shoulder instability with bone loss. CONCLUSIONS: Fellowship has a significantly higher impact than residency on industry-related decision-making. Fellowship-trained sports surgeons should consider seeking additional training in the treatment of multi-ligamentous knee injuries, posterior cruciate ligament injuries, shoulder instability with bone loss, and elbow disorders. The current findings were limited by the relatively small respondent pool, which represented only 26% of sports medicine fellowship programs in the United States.

The effect of platelet enriched plasma on clinical outcomes in patients with femoroacetabular impingement following arthroscopic labral repair and femoral neck osteoplasty.

To compare the clinical outcome of patients treated with and without platelet-rich plasma (PRP) injection while undergoing arthroscopic labral repair and femoral neck osteoplasty for femoral acetabular impingement. Patients were randomized at the time of surgery to receive either an intra-articular injection of 5 cc of PRP, or an equal volume of 0.9% normal saline. All patients underwent arthroscopic labral repair and osteoplasty of the femoral neck and, at the conclusion of the case, received the injection. One week following surgery, thigh circumference (measured 10 cm distal to the tip of the greater trochanter) and the presence of ecchymosis of the thigh were recorded. Clinical outcome scores, including Non-Arthritic Hip Score, Modified Harris Hip Score and Hip Outcome Score were collected prior to surgery at 1, 3, 6 and a minimum of 12 months post-operatively. Thirty-five patients were enrolled into this study. Twenty patients received a PRP injection and 15 received a saline injection. Thigh circumference was compared pre-operatively and 1 week post-operatively. There was no significant difference between the two groups. Ecchymosis was compared between the two groups at 1 week post-operatively. Four of the 20 patients in the PRP group and 10 of the 15 in the placebo group demonstrated bruising on the lateral thigh. This was compared with a Chi-Square test and found to be statistically significant (P = 0.005). There was no significant difference in any of the outcome scores between the two groups. An intra-articular injection of PRP after labral repair did not improve the clinical outcome up to 1 year post-operatively in patients undergoing arthroscopic labral repair and osteoplasty of the femoral neck. Level of evidence is level I study.

Radiological errors in the Canadian Journal of Emergency Medicine.

OBJECTIVES: To systematically evaluate the accuracy of text descriptions and labeling of radiologic images published in the Canadian Journal of Emergency Medicine (CJEM). Error detection by radiologists and emergency physicians and the clinical significance and educational value of these errors were assessed. Errors were also correlated with radiologist involvement in publication and imaging modality. METHODS: Thirty-three issues of CJEM were examined from January 2003 to May 2008. Electronic copies of all radiologic images published were obtained with their caption and description from the text. Identifying information was removed to present images in an anonymous fashion. Images were presented to two radiologists who, working in consensus, critically appraised each image and accompanying text. Images were then presented to two emergency department physicians who, working in consensus, critically appraised each image and accompanying text. All images with errors detected by either radiology or emergency physicians were then discussed to determine if errors would have affected clinical management or educational value. The emergency physicians also identified "underlabeled" images where it was felt that further labeling would enhance their educational value. RESULTS: Forty-five articles with 82 images were obtained. At least one error was observed in 18 (40%) articles and 20 (24%) images. Two errors were present in three images, resulting in 23 errors. Of the 23 errors, 17 were image description errors and 6 were labeling errors. Five errors were detected by both radiology and emergency physicians, whereas 15 were detected only by radiologists and 3 were detected only by emergency physicians. Of these errors, 12 (52%) were rated as potentially affecting both clinical management and educational value, 5 (22%) as only affecting educational value, and 6 (26%) as nonsignificant. Radiologists were involved in six articles, including 12 images that contained no errors. There was no official radiologist involvement in 39 articles, including 70 images, 18 (26%) of which contained errors. In addition, 26 images were identified by emergency physicians as potentially benefiting from enhanced labeling to improve educational value. CONCLUSIONS: Radiologic images published in the CJEM are generally of high quality; however, 23 errors were found in 82 images, 18 (78%) of which were rated as potentially affecting clinical management, educational value, or both. Radiologist involvement in the publication process may be of assistance as no errors were seen in articles that included radiologists as authors.

Clinical assessment of scapula and hip joint function in preadolescent and adolescent baseball players.

BACKGROUND: Proper scapulothoracic and hip mechanics are essential aspects of the throwing kinetic chain. Little is known regarding these entities in preadolescent and adolescent baseball players. HYPOTHESIS: Scapular malposition and dyskinesis as well as hip dysfunction are highly prevalent in preadolescent and adolescent baseball players and may be identified by simple clinical testing. STUDY DESIGN: Descriptive laboratory study. METHODS: A total of 112 baseball players aged 7 to 18 years were recruited from local Little Leagues, traveling teams, and high schools. Participants were divided into 2 groups: preadolescents (players aged 7-12 years) and adolescents (players aged 13-18 years). Scapular symmetry was tested with the yes/no method of Kibler and by measuring forward shoulder posture via the "coracoid distance." Hip abductor strength was measured by use of a handheld digital dynamometer. Functional gluteal and core strength was assessed by video analysis of the subjects performing the single-legged squat test. Hip range of motion was measured in the prone position by use of a handheld goniometer. RESULTS: Compared with the preadolescent group, the adolescent group had a significantly higher prevalence of scapular dyskinesis in the throwing shoulder (50% vs 25.9%, P = .011). The adolescents had significantly higher normalized hip abduction strength in both the stride (17.41 vs 12.62 N/kg, P < .001) and stance (17.82 vs 12.61 N/kg, P < .001) legs. The preadolescent group was unable to perform the single-legged squat test correctly in either the stance (0% preadolescent vs 13% adolescent, P = .0127) or stride (0% preadolescent vs 9.3% adolescent, P = .0567) leg. The mean coracoid distance was elevated in the dominant (throwing) shoulder after controlling for scapular dyskinesis (P < .0001). Presence of scapular dyskinesis was associated with a higher mean coracoid distance (P = .0067). CONCLUSION: There was a high prevalence of dominant shoulder scapular dyskinesis in the adolescent compared with the preadolescent group, as well as universally poor single-legged squat test performance. The mean coracoid distance was higher in the dominant or throwing side compared with the nondominant side independent of scapular dyskinesis. Presence of scapular dyskinesis was associated with higher mean coracoid distance. CLINICAL RELEVANCE: Identification of players thought to be at increased risk for throwing injuries and initiation of targeted rehabilitation programs may decrease injury rates in preadolescent and adolescent baseball players.

Biomechanical comparison of the interval throwing program and baseball pitching: upper extremity loads in training and rehabilitation.

BACKGROUND: The interval throwing progression has been part of baseball rehabilitation and conditioning for decades, yet little is known about the upper extremity loads an athlete is subjected to during this progression. HYPOTHESIS: A biomechanical comparison of fastball pitching, variable-effort pitching, and throwing various flat-ground distances will show significant torque differences in the throwing shoulder and elbow. STUDY DESIGN: Descriptive laboratory study. METHODS: Twenty-nine healthy college baseball pitchers were analyzed using a quantitative motion analysis system. The participants threw from flat ground at distances of 18, 27, 37, and 55 m, having been instructed to throw "hard, on a horizontal line." The participants then threw fastballs 18.4 m from a mound at 3 different effort levels: 60%, 80%, and full effort. The kinetic values for humeral internal rotational torque (HIRT) and elbow valgus load (EVL) were extracted for each throw. Repeated-measures analyses of variance (ANOVAs) were used to compare all 7 throwing conditions within pitchers. The kinetic data were also compared against ball velocity to evaluate throwing efficiency. A separate analysis was conducted using a 3-level repeated-measures ANOVA with post hoc paired t tests comparing just the variable-effort throws from the mound. RESULTS: No statistically significant differences were found in either HIRT or EVL between any of the flat-ground distances and throwing from the mound (P > .05). Despite similar biomechanical loads compared with the mound, throwing from flat ground showed significantly decreased ball velocity (82% of maximum). Statistically significant differences were found in humeral internal rotational torque and elbow valgus load between fastball pitching off the mound at 60% and 100%, as these parameters increased with throwing effort (P < .05). At 60% perceived effort from the mound, pitchers generated forces of 76% and ball speeds approaching 84% of maximum. CONCLUSION: Partial-effort pitching demonstrates significantly lower loads on the shoulder and elbow. Flat-ground throwing at even the shortest distances had similar biomechanical loads compared with pitching from the mound, yet at significantly lower ball velocity. This illustrates the mechanical advantage and increased efficiency of throwing from a mound. No increase in shoulder or elbow loads was seen with increasing distances from flat ground, as pitchers began using a "crow hop" for the longer distances, facilitating the throw with their lower extremity. The mechanical advantage of throwing from a mound or using the crow hop is likely protective during rehabilitation and training throws. CLINICAL RELEVANCE: The findings of this study may be used to improve rehabilitation programs designed for baseball players returning from shoulder or elbow injury.

Pitch velocity is a predictor of medial elbow distraction forces in the uninjured high school-aged baseball pitcher.

BACKGROUND: Medial elbow injuries are common among baseball pitchers. Easily accessed methods to assess medial elbow stress may be useful in identifying individuals with increased injury risk. HYPOTHESIS: Pitch velocity (PV) is positively associated with higher medial elbow adduction moments. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Participants included 26 uninjured high school pitchers, 15 to 18 years in age. Three-dimensional data and PV were collected as athletes threw 10 fastballs for strikes to a regulation-distance target. Variables of interest were the normalized peak internal elbow adduction moment and peak PV. Linear regression was performed to evaluate the influence of PV on the adduction moment. RESULTS: For the group, mean PV was 71 mph (range, 58-81 mph), and the adduction moment was 0.558 Nm/Ht × mass (range, 0.378-0.723). PV was positively associated with the adduction moment (P < 0.01, R(2)= 0.373). CONCLUSIONS: Talented young pitchers may be more susceptible to elbow injuries as a consequence of a biomechanical coupling between PV and upper extremity joint moments. CLINICAL RELEVANCE: PV may be measured easily and serve as an indicator of medial elbow stress.

Outcome of type II superior labral anterior posterior repairs in elite overhead athletes: Effect of concomitant partial-thickness rotator cuff tears.

BACKGROUND: There are conflicting reports in the literature regarding the outcome of superior labral anterior posterior (SLAP) repairs in overhead athletes and a paucity of data demonstrating ability to return to prior level of competition. HYPOTHESIS: Kerlan-Jobe Orthopaedic Clinic shoulder and elbow score provides more accurate assessment of shoulder function and ability to return to previous level of athletic competition after SLAP lesion repair than does the conventional American Shoulder and Elbow Surgeons scoring system. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Twenty-three elite (collegiate or professional) overhead athletes who were more than 1-year status postarthroscopic repair of type II SLAP lesions were evaluated using both the Kerlan-Jobe Orthopaedic Clinic shoulder and elbow score and American Shoulder and Elbow Surgeons score. P values were computed using the analysis of variance model. Postoperative American Shoulder and Elbow Surgeons and Kerlan-Jobe Orthopaedic Clinic scores from subjects were compared with control values obtained from a healthy athletic cohort; the relationship between the scores was investigated using the linear regression model and assessed using Pearson correlations. RESULTS: At a mean 38-month follow-up, 13 athletes were playing pain free at the time of the questionnaire administration, 6 were playing with pain, and 4 were not playing because of pain. Regarding American Shoulder and Elbow Surgeons scores, 22 athletes (96%) had good-excellent scores, whereas 1 (4%) had a fair score. The Kerlan-Jobe Orthopaedic Clinic scores revealed 9 excellent (39%), 3 good (13%), 4 fair (17%), and 7 poor (30%) results for the same study group. Of the 23 patients, 13 (57%) had returned to their pain-free preinjury levels of competition at final follow-up. The inability to return to this level of competition correlated with the presence of a partial-thickness rotator cuff tear (P = .0059). The Kerlan-Jobe Orthopaedic Clinic demonstrated better overall accuracy (85%) than did the American Shoulder and Elbow Surgeons (70%) in evaluating return to pain-free preinjury levels. CONCLUSION: Return to preinjury level of competition for elite overhead athletes after type II SLAP lesion repairs was 57%, despite high American Shoulder and Elbow Surgeons scores. Return to play status correlated with the presence of a partial-thickness rotator cuff tear. The Kerlan-Jobe Orthopaedic Clinic score, designed specifically for the evaluation of the overhead athlete, was a more accurate assessment tool than was the American Shoulder and Elbow Surgeons in this population of elite overhead athletes with SLAP tears.

Clinical follow-up of professional baseball players undergoing ulnar collateral ligament reconstruction using the new Kerlan-Jobe Orthopaedic Clinic overhead athlete shoulder and elbow score (KJOC Score).

BACKGROUND: There are no validated outcome measures consistently used in the literature to report results of ulnar collateral ligament reconstruction in overhead athletes. HYPOTHESIS: The Kerlan-Jobe Orthopaedic Clinic Overhead Athlete Shoulder and Elbow score (KJOC score) will correlate with other validated scores for upper extremity assessment but will be more accurate in evaluating ulnar collateral ligament reconstruction outcomes in professional baseball players. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Fifty-five professional baseball players who underwent ulnar collateral ligament reconstruction were asked to complete the KJOC score, the Disabilities of the Arm, Shoulder and Hand (DASH) score, and the DASH sports module. Players were separated into 3 categories-(1) playing without pain, (2) playing with pain, and (3) not playing because of pain-and compared with 123 asymptomatic throwers. Pearson (parametric) and Spearman rank (nonparametric) correlations among the 3 systems were conducted to validate the KJOC score. Means across categories were compared using a Wilcoxon rank-sum test, and a threshold score separating categories 1 and 3 was determined using receiver operator characteristic discrimination analysis. RESULTS: Significant correlations were found between the KJOC score and the DASH (-.693, P < .0001), and the DASH sports module (-0.804, P < .0001). Only the KJOC score was able to discriminate between categories 2 and 3, as well as category 1 and the uninjured population. In addition, the KJOC score was the most sensitive and accurate method of discriminating category 1 from category 3, with a threshold score of 81.3. CONCLUSION: The results of this study validate the use of the KJOC score for evaluation of overhead athletes undergoing ulnar collateral ligament reconstruction. The KJOC score is the most sensitive score for detecting subtle changes in performance in the throwing athlete.

The development and validation of a functional assessment tool for the upper extremity in the overhead athlete.

BACKGROUND: There are no validated upper extremity instruments designed specifically to evaluate the performance and function of overhead athletes. Current shoulder and elbow scoring systems may not be sensitive to subtle changes in performance in this high-demand population. HYPOTHESIS: The scoring system developed in this study will be valid, reliable, and responsive in the evaluation of overhead athletes. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Based on the results of a pilot questionnaire administered to 21 overhead athletes, a final 10-item questionnaire was developed. Two hundred eighty-two healthy, competitive overhead athletes completed the new questionnaire, as well as 2 established upper extremity questionnaires, and were self-assigned into injury categories: (1) playing without pain, (2) playing with pain, and (3) not playing due to pain. Correlations between the scores and differences between injury categories were measured. Responsiveness testing was performed in an additional group of 55 injured athletes, comparing their scores before and after an intervention. RESULTS: The new score showed high correlation with the Disabilities of the Arm, Shoulder and Hand (DASH) score and the DASH sports/performing arts module. The new score correctly stratified overhead athletes by injury category (P < .0001). The new score also demonstrated excellent responsiveness, varying appropriately with improvements in injury category after treatment of injuries (P < .05). CONCLUSION: The new patient-reported instrument is valid and responsive in the evaluation of overhead athletes. Reliability was also demonstrated for the 13-item pilot questionnaire. The results support its use for the functional assessment of overhead athletes in future studies.

The effect of pitching biomechanics on the upper extremity in youth and adolescent baseball pitchers.

BACKGROUND: Increased pitch counts have been linked to increased complaints of shoulder and elbow pain in youth baseball pitchers. Improper pitching mechanics have not been shown to adversely affect the upper extremity in youth pitchers. HYPOTHESIS: The correct performance of 5 biomechanical pitching parameters correlates with lower humeral internal rotation torque and elbow valgus load, as well as higher pitching efficiency, in youth and adolescent pitchers. STUDY DESIGN: Descriptive laboratory study. METHODS: In sum, 169 baseball pitchers (aged 9-18) were analyzed using a quantitative motion analysis system and a high-speed video while throwing fastballs. The correct performance of 5 common pitching parameters was compared with each pitcher's age, humeral internal rotation torque, elbow valgus load, and calculated pitching efficiency. RESULTS: Motion analysis correlated with video analysis for all 5 parameters (P < .05). Youth pitchers (aged 9-13) performing 3 or more parameters correctly showed lower humeral internal rotation torque, lower elbow valgus load, and higher pitching efficiency (P < .05). CONCLUSIONS: Youth pitchers with better pitching mechanics generate lower humeral internal rotation torque, lower elbow valgus load, and more efficiency than do those with improper mechanics. Proper pitching mechanics may help prevent shoulder and elbow injuries in youth pitchers. CLINICAL RELEVANCE: The parameters described in this study may be used to improve the pitching mechanics of youth pitchers and possibly reduce shoulder and elbow pain in youth baseball pitchers.

Electromyographic analysis of forearm muscles in professional and amateur golfers.

BACKGROUND: No fine-wire electromyography studies have been performed to compare the activity of forearm muscles in professional golfers versus amateur golfers. HYPOTHESIS: The fine-wire electromyographic activity of forearm muscles differs between professional and amateur golfers during the different phases of the golf swing. STUDY DESIGN: Controlled laboratory study. METHODS: Ten male right-handed amateur golfers and 10 male right-handed professional golfers without history of elbow symptoms were tested with fine-wire electromyographic electrodes inserted into the flexor carpi radialis, pronator teres, flexor carpi ulnaris, and extensor carpi radialis brevis muscles of both forearms. Electromyographic data were synchronized with video data, and the muscle activity was expressed as a percentage of maximum manual muscle test activity for each phase of the golf swing. RESULTS: Compared with professional golfers, amateur golfers had more muscle activity in the pronator teres of the trail arm (right arm in a right-handed golfer) in the forward swing phase (120.9% maximum manual muscle test vs 57.4% maximum manual muscle test; P = .04) and a trend toward increased activity in the acceleration phase (104.8% maximum manual muscle test vs 53.1% maximum manual muscle test; P = .08). In contrast, professional golfers had more muscle activity in the pronator teres of the lead arm (left arm in a right-handed golfer) in the acceleration phase (88.1% maximum manual muscle test vs 36.3% maximum manual muscle test; P = .03) and a trend toward increased activity in the early follow-through phase (58.1% maximum manual muscle test vs 28.8% maximum manual muscle test; P = .06). CONCLUSION: Pronator teres muscle activity in the golf swing differs significantly between professional and amateur golfers. CLINICAL RELEVANCE: Exercises with an emphasis on stretching and strengthening of the pronator teres may be useful in treating and/or preventing medial epicondylitis in amateur golfers.

The effect of tennis racket grip size on forearm muscle firing patterns.

BACKGROUND: Inappropriately sized tennis racket grip is often cited in the popular media as a risk factor for overuse injuries about the forearm and elbow. Currently, a hand measurement technique developed by Nirschl is commonly used by tennis racket manufacturing companies as the method for determining a player's "recommended" grip size. HYPOTHESIS: Quarter-inch changes from that recommended by Nirschl in tennis racket grip size will have no significant effect on forearm muscle firing patterns. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen asymptomatic Division I and II collegiate tennis players performed single-handed backhand ground strokes with rackets of 3 different grip sizes (recommended measurement, undersized (1/4) in, and oversized (1/4) in). Fine-wire electromyography was used to measure muscle activity in extensor carpi radialis longus and brevis, extensor digitorum communis, flexor carpi radialis, and pronator teres. Repeated-measure analysis of variance was used for within-group comparisons, comparing different grips in specified phases for backhand ground strokes (P