SHOULDER WEAKNESS IN PROFESSIONAL BASEBALL PITCHERS

The purposes of this study were to: 1) compare shoulder range of motio n and strength in professional baseball pitchers (N = 47) compared wit h age-matched controls (N = 16), and 2) examine the relationship of in jury history to strength and range of motion. Based on injury history pitchers were categorized as: 1) none (N = 26), 2) injury requiring co nservative intervention (N = 9), or 3) injury requiring surgical inter vention (N = 12). Range of motion was measured for internal rotation ( IROM) and external rotation (EROM). Eccentric strength was measured by hand-held dynamometer for internal rotation (IR), external rotation ( ER), abduction (ABD), and supraspinatus muscle (SUP) strength. Injury history had no effect on strength and range of motion. Dominant EROM w as greater in pitchers, P < 0.0001, and controls, P < 0.05, with pitch ers having greater EROM motion bilaterally P < 0.0001. Pitchers were w eaker in SUP an the dominant vs nondominant side, P < 0.0001, and on t he dominant side for weight adjusted ER, ABD, P < 0.01, and SUP, P < 0 .0001, compared with controls. In conclusion, dominance and pitching r esulted in soft tissue adaptation. Pitchers displayed weakness in thre e of four tests by comparison with controls, suggesting that the deman ds of pitching are insufficient to produce eccentric strength gains an d may in fact lead to weakness. Dominant-side SUP weakness in pitchers may reflect subclinical pathology or chronic fatigue.