Deltoid Muscle Disruption

Deltoid muscle disruption is a partial or complete rupture of the deltoid muscle or its attachment to bone. The deltoid is an important muscle for shoulder function and motion. With this rare injury, the deltoid muscle pulls off the roof of the shoulder (acromion), end of the collarbone, or part of the shoulder blade (scapula), resulting in loss of one attachment of the deltoid muscle and thus loss of function of this muscle. It is even less common for the deltoid to pull off the humerus (arm bone). This condition happens most commonly following open shoulder surgery when a surgeon has surgically taken down and repaired the deltoid muscle from the acromion and the deltoid repair fails because the patient is not compliant after surgery. Deltoid muscle disruption can result in poor shoulder function.