The tendon supraspinatus is a critical component of the rotator cuff, serving as the primary stabilizer for the shoulder joint during overhead activities. This thick, triangular tendon connects the supraspinatus muscle to the greater tubercle of the humerus, initiating the abduction of the arm for the first fifteen degrees before the deltoid muscle takes over. Its positioning beneath the acromion arch makes it susceptible to impingement and repetitive stress, which are common precursors to injury in both athletes and the general population.
Anatomy and Function
Anatomically, the supraspinatus tendon is one of four tendons that form the rotator cuff, a musculotendinous cuff surrounding the glenohumeral joint. The tendon runs laterally from the supraspinatus fossa of the scapula, passing through the subacromial space to insert on the superior facet of the greater tubercle. Its primary biomechanical role is to depress the humeral head against the upward pull of the deltoid during arm elevation, preventing superior migration that would lead to dislocation or impingement.
Common Pathologies
Disorders of the tendon supraspinatus are among the most frequent causes of shoulder pain and disability. Supraspinatus tendinopathy often results from chronic overuse, leading to degenerative changes or partial tears. Acute trauma, such as a fall on an outstretched hand, can cause full-thickness tears, resulting in significant weakness during active abduction. Additionally, calcific tendinitis, where calcium deposits form within the tendon, can provoke severe episodes of pain and reduced range of motion.
Symptoms and Diagnosis
Individuals with supraspinatus pathology typically report pain in the lateral shoulder that radiates down the deltoid, particularly during overhead reaching or lying on the affected side. Physical examination often reveals weakness during resisted abduction, especially between sixty and ninety degrees of elevation. Diagnostic imaging plays a crucial role; Magnetic Resonance Imaging (MRI) and ultrasound are highly effective in visualizing tendon integrity, tear size, and surrounding inflammation to confirm the clinical suspicion.
Treatment Strategies
Management of tendon supraspinatus injuries is typically conservative initially, focusing on reducing inflammation and restoring mechanics. Non-steroidal anti-inflammatory drugs (NSAIDs), coupled with structured physical therapy to improve scapular stability and rotator cuff strength, are the cornerstone of non-operative treatment. Corticosteroid injections may be utilized for acute flare-ups of pain, though their use is balanced against potential long-term risks to tendon integrity.
Surgical Intervention
When conservative measures fail to alleviate persistent pain or restore function, surgical options are considered. Arthroscopic repair is the gold standard for significant tears, where suture anchors are used to reattach the tendon to the humeral head. Post-operative rehabilitation is a meticulous process, requiring a gradual progression from immobilization to passive range of motion, and eventually to strengthening exercises, to ensure successful tendon healing and prevent re-tear.
Prognosis and Prevention
Prognosis for recovery varies based on tear size, patient age, and adherence to rehabilitation protocols. Smaller tears and partial thickness injuries generally respond well to non-surgical management, while larger full-thickness tears may require longer recovery periods even after surgery. Prevention centers on maintaining flexibility of the posterior shoulder capsule, strengthening the rotator cuff and scapular muscles, and avoiding sudden spikes in training intensity, particularly in throwing sports or occupations requiring repetitive overhead work.
