RT Journal Article SR Electronic T1 Evaluation of shoulder internal rotator muscle strength in baseball players with physical signs of glenohumeral joint instability JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 430 OP 432 DO 10.1136/bjsm.37.5.430 VO 37 IS 5 A1 Falla, D L A1 Hess, S A1 Richardson, C YR 2003 UL http://bjsm.bmj.com/content/37/5/430.abstract AB Objectives: To identify whether subjects with glenohumeral translational instability present with a strength deficit in their internal rotator musculature, and therefore to determine if general strengthening exercises are warranted for the management of this condition. Methods: Eighteen male baseball players were allocated to two groups on the basis of expert clinical evaluation of the presence (n = 8) or absence (n = 10) of shoulder translational instability. A strain gauge was used to calculate the force generated during maximal isometric internal rotation contractions in neutral shoulder rotation and 30° of internal rotation. Results: The Mann-Whitney test identified no significant difference in force production during the maximum contractions in neutral rotation between the two subject groups. In the position of 30° shoulder internal rotation, subjects with glenohumeral translational instability produced significantly greater force than the control group (p<0.05). Conclusions: High load strength testing cannot be used as a diagnostic tool to identify people with glenohumeral instability. Similarly, heavy resistance strengthening exercises for the internal rotator musculature are not warranted during rehabilitation.