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Background: The incidence of upper extremity injury in baseball pitchers has increased over the past decade. This has resulted in a large body of research mainly focused on the kinematic and kinetic patterns of the elbow and shoulder to elucidate the cause of these injuries, with little attention on studying the associations of forearm rotation and upper arm joint moments. Hypothesis: There will be significant differences in forearm kinematics and kinetics when comparing the fastball pitch with the curveball pitch. There will be a positive association between forearm kinetics, specifically supination and pronation moments, and the elbow varus moment. Study Design: Descriptive laboratory study. Methods: A total of 78 pitchers were recruited for this study, and they underwent a pitching analysis using motion analysis techniques. A random-intercept, mixed-effects regression model was used to determine differences in forearm kinematics and kinetics when pitching a fastball compared with a curveball, as well as to determine if associations existed between forearm supination and pronation moments and the elbow varus moment. Results: There were a number of significant differences in forearm position when pitching a fastball compared with a curveball, with the curveball producing a more supinated forearm position. Significant associations were found between increasing forearm supination moments and an increase in elbow varus moment for both the fastball and the curveball (P = .002 and P < .001, respectively). For every 1-N·m increase in the supination moment, there was a 1-N·m and 1.1-N·m increase in the elbow varus moment for the fastball and curveball, respectively. Conclusion: The results demonstrated that the forearm position was not associated with the elbow varus moment. However, the supination moment was associated with the elbow varus moment. Clinical Relevance: On the basis of these findings, pitching coaches and trainers can understand the implications of proper lower arm pitching mechanics in the later portion of the pitch cycle as a potential risk of injury and, therefore, can develop coaching strategies to reduce incorrect positioning, especially when players are pitching the curveball. [ABSTRACT FROM AUTHOR]

Background: Access to health care services is a critical component of health care reform and may differ among patients with different types of insurance. Hypothesis/Purpose: The purpose was to compare adolescents with private and public insurance undergoing surgery for anterior cruciate ligament (ACL) and/or meniscal tears. We hypothesized that patients with public insurance would have a delayed presentation from the time of injury and therefore would have a higher incidence of chondral injuries and irreparable meniscal tears and lower preoperative International Knee Documentation Committee (IKDC) scores than patients with private insurance. Study Design: Cross-sectional study; Level of evidence, 3. Methods: This was a retrospective study of patients under 21 years of age undergoing ACL reconstruction and/or meniscal repair or debridement from January 2013 to March 2016 at a single pediatric sports medicine center. Patients were identified by a search of Current Procedural Terminology (CPT) codes. A chart review was performed for insurance type; preoperative diagnosis; date of injury, initial office visit, and surgery; preoperative IKDC score; intraoperative findings; and procedures. Results: The study group consisted of 119 patients (mean age, 15.0 ± 1.7 years). Forty-one percent of patients had private insurance, while 59% had public insurance. There were 27 patients with isolated meniscal tears, 59 with combined meniscal and ACL tears, and 33 with isolated ACL tears. The mean time from injury to presentation was 56 days (range, 0-457 days) in patients with private insurance and 136 days (range, 0-1120 days) in patients with public insurance (P = .02). Surgery occurred, on average, 35 days after the initial office visit in both groups. The mean preoperative IKDC score was 53 in both groups. Patients with meniscal tears with public insurance were more likely to require meniscal debridement than patients with private insurance (risk ratio [RR], 2.3; 95% CI, 1.7-3.1; P = .02). Patients with public insurance were more likely to have chondral injuries of grade 2 or higher (RR, 4.4; 95% CI, 3.9-5.0; P = .02). Conclusion: In adolescent patients with ACL or meniscal tears, patients with public insurance had a more delayed presentation than those with private insurance. They also tended to have more moderate-to-severe chondral injuries and meniscal tears, if present, that required debridement rather than repair. More rapid access to care might improve the prognosis of young patients with ACL and meniscal injuries with public insurance. [ABSTRACT FROM AUTHOR]

Background: The incidence of upper extremity injuries in baseball pitchers is increasing. Over the past decade there has been a great deal of research attempting to elucidate the cause of these injuries, focusing mainly on the mechanics of the pitching arm with no examination of other key segments, such as the trunk. This is surprising, as coaches will often comment on trunk position in an effort to improve pitching outcomes. Purpose: To determine the association between contralateral trunk lean and ball velocity and the moments about the elbow and glenohumeral joint. Study Design: Descriptive laboratory study. Methods: A total of 99 pitchers were recruited for this study and underwent a pitching analysis using 3-dimensional motion analysis techniques. A random intercept mixed-effects regression model was used to determine if statistically significant associations existed between contralateral trunk lean (away from the pitching arm side) and ball velocity, as well as the elbow varus moment and glenohumeral internal rotation moment. Results: The results demonstrated that the greatest contralateral trunk lean occurs around the time of the peak elbow varus moment. Statistically significant associations were found between contralateral trunk lean and increased ball velocity (P = .003) indicating that for every 10 increase in contralateral lean, ball velocity increased 0.5 m/s. Results also indicated that for every 10 increase in contralateral lean, elbow varus moments increased by 3.7 Nm and glenohumeral internal rotation moments increased by 2.5 Nm (P \ .001 for both). Conclusion: Study findings indicate that the positioning of the trunk plays a substantial role in pitching performance and pitcher injury potential. This work helps to demonstrate the importance of proper trunk mechanics in pitching and highlights the need for future research to understand the contribution of the trunk to pitching mechanics. Clinical Relevance: Pitching coaches and trainers can use the results of this study to stress the importance of proper trunk mechanics in pitching. Specifically, improving core strength and trunk control in an effort to maintain a more upright posture through the pitching cycle can reduce upper extremity joint stresses. [ABSTRACT FROM AUTHOR]

Background: Anterior cruciate ligament (ACL) reconstruction failure occurs in up to 10% of cases. Technical errors are considered the most common cause of graft failure despite the absence of validated studies. Limited data are available regarding the agreement among orthopaedic surgeons regarding the causes of primary ACL reconstruction failure and accuracy of graft tunnel Placement.Hypothesis: Experienced knee surgeons have a high level of interobserver reliability in the agreement about the causes of primary ACL reconstruction failure, anatomic graft characteristics, and tunnel placement.Study Design: Cohort study (diagnosis); Level of evidence, 3.Methods: Twenty cases of revision ACL reconstruction were randomly selected from the Multicenter ACL Revision Study (MARS)database. Each case included the patient's history, standardized radiographs, and a concise 30-second arthroscopic video taken at the time of revision demonstrating the graft remnant and location of the tunnel apertures. All 20 cases were reviewed by 10 MARS surgeons not involved with the primary surgery. Each surgeon completed a 2-part questionnaire dealing with each surgeon's training and practice, as well as the placement of the femoral and tibial tunnels, condition of the primary graft, and the surgeon's opinion as to the causes of graft failure. Interrater agreement was determined for each question with the kappa coefficient and the prevalence-adjusted, bias-adjusted kappa (PABAK).Results: The 10 reviewers have been in practice an average of 14 years and have performed at least 25 ACL reconstructions per year, and 9 were fellowship trained in sports medicine. There was wide variability in agreement among knee experts as to the specific causes of ACL graft failure. When participants were specifically asked about technical error as the cause for failure, inter-observer agreement was only slight (PABAK = 0.26). There was fair overall agreement on ideal femoral tunnel placement (PABAK= 0.55) but only slight agreement on whether a femoral tunnel was too anterior (PABAK = 0.24) and fair agreement on whether it was too vertical (PABAK = 0.46). There was poor overall agreement for ideal tibial tunnel placement (PABAK = 0.17).Conclusion: This study suggests that more objective criteria are needed to accurately determine the causes of primary ACL graft failure as well as the ideal femoral and tibial tunnel placement in patients undergoing revision ACL reconstruction. [ABSTRACT FROM AUTHOR]

Current pitching literature focuses primarily on the elbow and glenohumeral joints. This has led to a paucity of information regarding the forearm and wrist, and the limited data available are inconsistent. Therefore, this article seeks to provide a comprehensive description of the kinematics and kinetics of the wrist and forearm for the fastball, curveball, slider/cutter, and change-up for college-level baseball pitchers. Thirty-six collegiate pitchers were evaluated using motion analysis techniques. Results indicated that pitching the curveball generated the greatest forearm supination (16 ± 13°) compared with the other three pitch types (p < 0.05). The curveball and slider/cutter were pitched with less wrist extension and greater ulnar deviation compared with the fastball and change-up. The curveball was found to produce the greatest ulnar moment (7.3 ± 2.2 Nm) and was significantly different from the moments noted when pitching the fastball and change-up (5.1 ± 1.9 and 4.9 ± 1.9 Nm, respectively;p < 0.05). These results indicate that it may be possible to objectively determine pitch type from kinematic data of the wrist and forearm. It may also be possible that coaches may be able to identify abnormal pitching mechanics from more proximal segments by understanding the motion of the wrist. [ABSTRACT FROM PUBLISHER]