Internal Rotation Lag Sign

Partial-thickness tears of the rotator cuff damage some but not all layers of the tendon tissue. In contrast, full-thickness tears extend through all layers of the tendon, often leading to a complete separation of the tendon from the bone.

The sensitivity of the Internal Rotation Lag Sign is high according to research published by Miller, Forrester, and Lewis in 2008, making it reliable for detecting significant injuries to the subscapularis muscle tendon but less effective for identifying mild or partial-thickness tears.

Internal rotation limitations often include pain and decreased range of motion due to stiff or painful shoulder or joints, rotator cuff injuries, or post-surgical changes. These can hinder daily activities and reduce overall shoulder function.