Deficits in Glenohumeral Passive Range of Motion Increase Risk of Shoulder Injury in Professional Baseball Pitchers: A Prospective Study.

BACKGROUND: Shoulder injuries from repetitive baseball pitching continue to be a serious, common problem. PURPOSE: To determine whether passive range of motion of the glenohumeral joint was predictive of shoulder injury or shoulder surgery in professional baseball pitchers. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Passive range of motion of the glenohumeral joint was assessed with a bubble goniometer during spring training for all major and minor league pitchers of a single professional baseball organization over a period of 8 successive seasons (2005-2012). Investigators performed a total of 505 examinations on 296 professional pitchers. Glenohumeral external and internal rotation was assessed with the pitcher supine and the arm abducted to 90° in the scapular plane with the scapula stabilized anteriorly at the coracoid process. Total rotation was defined as the sum of internal and external glenohumeral rotation. Passive shoulder flexion was measured with the pitcher supine and the lateral border of the scapula manually stabilized. After examination, shoulder injuries and injury durations were recorded by each pitcher's respective baseball organization and reported to the league as an injury transaction as each player was placed on the disabled list. RESULTS: Highly significant side-to-side differences were noted within subjects for each range of motion measurement. There were 75 shoulder injuries and 20 surgeries recorded among 51 pitchers, resulting in 5570 total days on the disabled list. Glenohumeral internal rotation deficit, total rotation deficit, and flexion deficit were not significantly related to shoulder injury or surgery. Pitchers with insufficient external rotation (<5° greater external rotation in the throwing shoulder) were 2.2 times more likely to be placed on the disabled list for a shoulder injury (P = .014; 95% CI, 1.2-4.1) and were 4.0 times more likely to require shoulder surgery (P = .009; 95% CI, 1.5-12.6). CONCLUSION: Insufficient shoulder external rotation on the throwing side increased the likelihood of shoulder injury and shoulder surgery. Sports medicine clinicians should be aware of these findings and develop a preventive plan that addresses this study's findings to reduce pitchers' risk of shoulder injury and surgery.

Deficits in glenohumeral passive range of motion increase risk of elbow injury in professional baseball pitchers: a prospective study.

BACKGROUND: Injuries to the elbow joint in baseball pitchers appear common. There appears to be a correlation between shoulder range of motion and elbow injuries. PURPOSE: To prospectively determine whether decreased ROM of the throwing shoulder is correlated with the onset of elbow injuries in professional baseball pitchers. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: For 8 consecutive years (2005-2012), passive range of motion of both the throwing and nonthrowing shoulders of all major and minor league pitchers within a single professional baseball organization were measured by using a bubble goniometer during spring training. In total, 505 examinations were conducted on 296 pitchers. Glenohumeral external rotation and internal rotation were assessed in the supine position with the arm at 90° of abduction and in the plane of the scapula. The scapula was stabilized per methods previously established. Total rotation was defined as the sum of external rotation and internal rotation. Passive shoulder flexion was assessed with the subject supine and the scapula stabilized per methods previously established. Elbow injuries and days missed because of elbow injuries were assessed and recorded by the medical staff of the team. Throwing and nonthrowing shoulder measurements were compared by using Student t tests; 1-tailed Fisher exact tests were performed to identify significant associations between shoulder motion and elbow injury. Nominal logistic regression was performed to determine the odds of elbow injury. RESULTS: Significant differences were noted during side-to-side comparisons within subjects. There were 49 elbow injuries and 8 surgeries in 38 players, accounting for a total of 2551 days missed. Neither glenohumeral internal rotation deficit nor external rotation insufficiency was correlated with elbow injuries. Pitchers with deficits of >5° in total rotation in their throwing shoulders had a 2.6 times greater risk for injury. Pitchers with deficit of ≥5° in flexion of the throwing shoulder had a 2.8 times greater risk for injury. CONCLUSION: Bilateral differences in shoulder total rotation and flexion had a significant effect on the risk for elbow injuries in pitchers. Clinicians need to be aware of these findings and plan preventive programs that address these issues in hopes of reducing elbow injuries.

Glenohumeral internal rotation measurements differ depending on stabilization techniques.

BACKGROUND: The loss of glenohumeral internal rotation range of motion in overhead athletes has been well documented in the literature. Several different methods of assessing this measurement have been described, making comparison between the results of studies difficult. HYPOTHESIS: Significant differences in the amount of internal rotation range of motion exist when using different methods of stabilization. STUDY DESIGN: Descriptive laboratory study. METHODS: THREE TECHNIQUES WERE USED BILATERALLY IN RANDOM FASHION TO MEASURE GLENOHUMERAL INTERNAL ROTATION RANGE OF MOTION: stabilization of the humeral head, stabilization of the scapula, and visual inspection without stabilization. An initial study on 20 asymptomatic participants was performed to determine the intrarater and interrater reliability for each measurement technique. Once complete, measurements were performed on 39 asymptomatic professional baseball players to determine if a difference existed in measurement techniques and if there was a significant side-to-side difference. A 2-way repeated-measures analysis of variance was used. RESULTS: While interrater reliability was fair between all 3 methods, scapular stabilization provided the best intrarater reliability. A statistically significant difference was observed between all 3 methods (P < .001). Internal rotation was significantly less in the dominant shoulder than in the nondominant shoulder (P < .001). CONCLUSION: Differences in internal rotation range of motion measurements exist when using different methods. The scapula stabilization method displayed the highest intrarater reproducibility and should be considered when evaluating internal rotation passive range of motion of the glenohumeral joint. CLINICAL RELEVANCE: A standardized method of measuring internal rotation range of motion is required to accurately compare physical examinations of patients. The authors recommend the use of the scapula stabilization method to assess internal rotation range of motion by allowing normal glenohumeral arthrokinematics while stabilizing the scapulothoracic articulation.