A profile of glenohumeral internal and external rotation motion in the uninjured high school baseball pitcher, part I: motion.
CONTEXT: The magnitude of motion that is normal for the throwing shoulder in uninjured baseball pitchers has not been established. Chronologic factors contributing to adaptations in motion present in the thrower's shoulder also have not been established. OBJECTIVES: To develop a normative profile of glenohumeral rotation motion in uninjured high school baseball pitchers and to evaluate the effect of chronologic characteristics on the development of adaptations in shoulder rotation motion. DESIGN: Cohort study. SETTING: Baseball playing field. PATIENTS OR OTHER PARTICIPANTS: A total of 210 uninjured male high school baseball pitchers (age = 16 +/- 1.1 years, height=1.8+/-0.1 m, mass=77.5+/-11.2 kg, pitching experience=6+/-2.3 years). INTERVENTION(S): Using standard goniometric techniques, we measured passive rotational glenohumeral range of motion bilaterally with participants in the supine position. MAIN OUTCOME MEASURE(S): Paired t tests were performed to identify differences in motion between limbs for the group. Analysis of variance and post hoc Tukey tests were conducted to identify differences in motion by age. Linear regressions were performed to determine the influence of chronologic factors on limb motion. RESULTS: Rotation motion characteristics for the population were established. We found no difference between sides for external rotation (ER) at 0 degrees of abduction (t(209) = 0.658, P = .51), but we found side-to-side differences in ER (t(209) =-13.012,P < .001) and internal rotation (t(209) =15.304, P < .001) at 90 degrees of abduction. Age at the time of testing was a significant negative predictor of ER motion for the dominant shoulder (R(2) = 0.019, P = .049) because less ER motion occurred at the dominant shoulder with advancing age. We found no differences in rotation motion in the dominant shoulder across ages (F(4,205) range, 0.451-1.730,P > .05). CONCLUSIONS: This range-of-motion profile might be used to assist with the interpretation of normal and atypical shoulder rotation motion in this population. Chronologic characteristics of athletes had no influence on range-of-motion adaptations in the thrower's shoulder. (+info)
A profile of glenohumeral internal and external rotation motion in the uninjured high school baseball pitcher, part II: strength.
CONTEXT: A database describing the range of normal rotator cuff strength values in uninjured high school pitchers has not been established. Chronologic factors that contribute to adaptations in strength also have not been established. OBJECTIVES: To establish a normative profile of rotator cuff strength in uninjured high school baseball pitchers and to determine whether bilateral differences in rotator cuff strength are normal findings in this age group. DESIGN: Cohort study. SETTING: Baseball playing field. PATIENTS OR OTHER PARTICIPANTS: A total of 165 uninjured male high school baseball pitchers (age = 16 +/- 1 years, height=1.8+/-0.1 m, mass=76.8+/-10.1 kg, pitching experience =7+/-2 years). MAIN OUTCOME MEASURE(S): Isometric rotator cuff strength was measured bilaterally with a handheld dynamometer. We calculated side-to-side differences in strength (external rotation [ER], internal rotation [IR], and the ratio of ER:IR at 90 degrees of abduction), differences in strength by age, and the influence of chronologic factors (participant age, years of pitching experience) on limb strength. RESULTS: Side-to-side differences in strength were found for ER, IR, and ER:IR ratio at 90 degrees of abduction. Age at the time of testing was a significant but weak predictor of both ER strength (R(2)=0.032, P = .02) and the ER:IR ratio (R(2)=0.051 , P = .004) at 90 degrees of abduction. CONCLUSIONS: We established a normative profile of rotator cuff strength for the uninjured high school baseball pitcher that might be used to assist clinicians and researchers in the interpretation of muscle strength performance in this population. These data further suggested that dominant-limb adaptations in rotator cuff strength are a normal finding in this age group and did not demonstrate that these adaptations were a consequence of the age at the time of testing or the number of years of pitching experience. (+info)
Performance after rotator cuff tear and operative treatment: a case-control study of major league baseball pitchers.
CONTEXT: Little is known about pitching performance or lack of it among Major League Baseball (MLB) pitchers who undergo operative treatment of rotator cuff tears. OBJECTIVE: To assess pitching performance outcomes in MLB players who needed operative treatment of rotator cuff tears and to compare performance in these athletes with that in a control group of MLB players. DESIGN: Case-control study. SETTING: Publicly available player profiles, press releases, and team injury reports. PATIENTS OR OTHER PARTICIPANTS: Thirty-three MLB pitchers with documented surgery to treat rotator cuff tears and 117 control pitchers who did not have documented rotator cuff tears were identified. MAIN OUTCOME MEASURE(S): Major League Baseball pitching attrition and performance variables. RESULTS: Players who underwent rotator cuff surgery were no more likely not to play than control players. Performance variables of players who underwent surgery improved after surgery but never returned to baseline preoperative status. Players who needed rotator cuff surgery typically were more experienced and had better earned run averages than control players. CONCLUSIONS: Pitchers who had symptomatic rotator cuff tears that necessitated operative treatment tended to decline gradually in performance leading up to their operations and to improve gradually over the next 3 seasons. In contrast to what we expected, they did not have a greater attrition rate than their control counterparts; however, their performances did not return to preoperative levels over the course of the study. (+info)