Shoulder problem Normally these tendons transmit the force of muscles originating on the shoulder Blade (scapula) to the arm providing motion and stability. The most commonly affected tendon is that of the supraspinatus muscle. Defects in the rotator cuff can come from an injury (cuff tear) or from degeneration (cuff wear). The degree to which a tendon is reparable depends on its quantity and quality. Degenerated tendons are often frail and retracted and may not be amenable to repair. Individuals that are elderly, smokers, or those having had cortisone injections often have weaker tendon tissue that fails without a significant injury. By
Subacromial bursitis (those) who were twenty-one to forty years old had less satisfactory results". The poorer outcome for patients over 60 years old was thought to be potentially related to "undiagnosed full-thickness tears of the rotator cuff". Subacromial bursitis Subacromial bursitis is a condition caused by inflammation of the bursa that separates the superior surface of the supraspinatus tendon (one of the four tendons of the rotator cuff) from the overlying coraco-acromial ligament, acromion, and coracoid (the acromial arch) and from the deep surface of the deltoid muscle. The subacromial bursa helps the motion of the supraspinatus tendon of the rotator cuff