Rotator Cuff Tears
Rotator cuff tears occur both traumatically and over time, without a specific traumatic event. A number of factors may be involved, such as a genetic predisposition, extrinsic impingement and biomechanical imbalance of the shoulder girdle musculature, and co-morbidities. Associated conditions, including AC joint arthritis, proximal biceps pathology and cartilage abnormalities may also be present.
The rotator cuff includes 4 muscles: supraspinatus, infraspinatus, teres minor and subscapularis. Their primary function is to provide dynamic stability to the shoulder joint by balancing force couples, maintaining a stable fulcrum for glenohumeral (shoulder) motion. Cuff tears are extremely variable in size, location and shape, and may be accompanied with atrophy of the affected rotator cuff muscle.
Physical Examination and Work-Up
Patients often present with pain exacerbated by overhead activities and lifting. Pain is commonly located in the region of the deltoid but may also be more diffuse in location. Our physicians will assess range of motion, strength and perform multiple clinical tests to assess the integrity of the rotator cuff and surrounding structures.
Shoulder Clinical Rotator Cuff Tests
This clinical test assesses the integrity of the supraspinatus. The arm is passively elevated to 90 degrees in the scapular plane. The patient is asked to slowly lower their arm. The test is positive when weakness or pain causes them to drop the arm to their side.
This clinical test assesses for supraspinatus weakness and/or impingement. The arm is abducted to 90 degrees within the scapular plane and internally rotated (thumb to floor). The examiner applies a downward force to the forearm while the patient attempts to resist.
This clinical test assesses the integrity of the superior aspect of the subscapularis. The patient presses their abdomen with the palm of the affected arm, maintaining shoulder internal rotation. If the elbow drops posteriorly, the test is positive for subscapularis pathology.
Lift Off Test:
This clinical test assesses the integrity of the inferior aspect of the subscapularis. The patient places their hand on their lumbar spine with the palm facing outward. The patient is asked to lift their hand off their back (internally rotating the shoulder). An inability to do so indicates subscapularis pathology.
External Rotation Lag Sign:
This clinical test assesses the integrity of the infraspinatus. The patient’s arm is at their side with the elbow bent to 90 degrees, palm rotated inward. The shoulder is passively externally rotated, keeping the elbow at their side. The patient is asked to maintain the externally rotated position. If they fail to do so, the arm drifts into internal rotation, consistent with infraspinatus pathology.
This clinical test assesses the teres minor. The patient’s shoulder is placed in 90 degrees of abduction with 90 degrees of external rotation. The patient is asked to maintain this position. An inability to do so (arm falls into internal rotation) is consistent with teres minor pathology.
X-rays assess for bony injury, such as a greater tuberosity fracture, calcific tendinitis, degenerative changes of the glenohumeral and AC joints, and for proximal migration of the humeral head (indicated chronic rotator cuff pathology). An MRI is obtained when suspicion for a tear exists. The MRI evaluates the tear size and shape, and degree of tear retraction if present. The degree of muscle fatty atrophy is best seen on the sagittal images.
Non-operative management, including physical therapy, NSAIDs and possible a subacromial corticosteroid injection, is often the first line of treatment for most small and/or partial rotator cuff tears. If non-operative management fails or the tear type indicates repair, a rotator cuff repair is recommended. Surgery to repair a torn rotator cuff most often involves reattaching the tendon to the head of humerus. The majority of rotator cuff tears are repaired arthroscopically.
Post Op Rehabilitation
Following Rotator Cuff Repair, the operative shoulder is protected in a sling for sling for 4-6 weeks depending on the extent of injury. Light exercises of the elbow, wrist and hand are started immediately following surgery. After initial immobilization, a therapist helps restore full range of motion of the shoulder, then progresses strengthening. Throughout the rehabilitation progression, assessments will be performed in the COSMO Fit Lab to provide an individualized, criterion-based progression of the rehabilitation protocol and will be shared with your therapist.