Why does glenohumeral internal rotation deficit (GIRD) in throwing athletes lead to rotator cuff injuries?

Doctor’s answer

GIRD is common in overhead athletes like baseball, badminton, and volleyball players, primarily due to repetitive force causing thickening and contracture of the posterior inferior capsule. When the loss of internal rotation exceeds the compensatory increase in external rotation, it alters the humeral head's rotation center, increasing mechanical impingement and shear forces on the superior labrum and rotator cuff, leading to SLAP tears and internal impingement. Proper 'sleeper stretch' and posterior capsule release are key to prevention and treatment.

This content is for education. Diagnosis, treatment, and rehabilitation require an individual assessment by a sports medicine specialist.