Avulsion fracture lesser tuberosity of the humerus usually occurs in association with fractures involving two or three parts of the proximal humerus or in association with a posterior fracture dislocation of the shoulder joint. The usual mechanism of injury resulting in an avulsion fracture is an abduction external rotation trauma of the shoulder. Because the subscapularis tendon is linked directly to the fractured fragment, avulsion causes insufficiency of the muscle-tendon unit.

Radiographer: TSRM Fabio Imola