This Quick Recertification Series is not meant to replace in-depth studying for the recertification exam and should be used only as an adjunct. Furthermore, the information contained here may not be sufficient to provide diagnosis and treatment in the clinical setting.
ROTATOR CUFF DISEASE
GENERAL FEATURES
• The rotator cuff is a group of four muscles (supraspinatus, infraspinatus, subscapularis, and teres minor) situated in the periscapular region whose tendons run intra-articularly through the glenohumeral joint and attach at the proximal humerus.
• The major function of this muscle group is to enhance the support of the humeral head in the glenoid. Several of the muscles also have rotational and abduction functions at this joint.
• Tendon disease in this group occurs on a spectrum from impingement/ tendinosis to partial rupture of the tendon(s), to full rupture of the tendon(s).
• Most commonly, rotator cuff tears occur in the dominant arm as a degenerative process caused by blood supply issues and bone spur growth in older adults and less commonly as an acute injury in younger adults.
• There is some evidence that rotator cuff tears may occur more commonly in smokers and that smokers have a more prolonged recovery from rotator cuff surgery.
CLINICAL ASSESSMENT
• History
– Patients generally complain of shoulder pain that radiates to the anterolateral portion of the arm and is worse with overhead reaching and rotational activities at the glenohumeral joint.
– The pain is usually described as worsening over time and interferes with the patient's ability to sleep.
– Muscle weakness and limited range of motion may accompany the pain.
• Physical examination
– Decrease in active range of motion at the shoulder, especially in rotation and flexion, is common in both impingement/tendinosis and rotator cuff tear.
– Weakness in external rotation may suggest an infraspinatus tear (and, although less common, a teres minor tear).
– The lift-off test (patient places hand, palm up, on back and lifts off back) is helpful when examining subscapularis function.
– The drop arm test is performed by the examiner passively positioning the patient's arm in abduction and then the patient attempts to slowly lower the arm. An abrupt drop of the arm is positive and may indicate damage to the rotator cuff.
– Provocative tests for presence of impingement include the Hawkins test and Neer impingement test.
■ In the Hawkins test, the patient holds the arm in 90° of glenohumeral flexion and flexes elbow; tester internally rotates the glenohumeral joint. Finding is positive if this maneuver induces pain.
■ In the Neer impingement test the patient holds the forearm in pronation as the examiner forcibly flexes at the glenohumeral joint while stabilizing the scapula. Finding is positive if pain is induced.
– In long-standing rotator cuff tears, you may see periscapular muscular atrophy.
DIAGNOSIS
• Presumptive diagnosis may be made by history and physical examination findings.
• Plain radiography of the shoulder may show signs of acromioclavicular bone spurring of humeral head elevation.
• Noncontrast T2-weighted MRI of the shoulder is the standard evaluation for suspected rotator cuff disease; however, results may be normal in impinge ment syndrome. Findings suggestive of impingement syndrome include narrowed subacromial space, rotator cuff tendinosis, and fluid in the bursa. Partial and full-thickness tendon tears are generally evident on MRI.
• MRI arthrography may be performed in patients with possible glenoid labrum tears or who have previously had intra-articular surgery.
TREATMENT
• Impingement syndrome
– May be treated conservatively with cryotherapy and NSAIDs during symptomatic flares. Patients may also benefit from physical therapy for cuff strengthening and the use of modalities to decrease edema in the subacromial space.
– A subacromial injection of corticosteroid may offer temporary relief but should be used judiciously.
– If conservative treatment fails, surgical subacromial decompression should be considered.
• Rotator cuff tear
– Partial tears may be treated in the same way as impingement syndrome.
– Full-thickness tears in a younger adult should be operatively repaired in either an open or arthroscopic approach followed by physical therapy.
– In the elderly and persons with longstanding tears, even full-thickness tears may be treated conservatively with the hopes of maintaining as much function as possible.
QUESTIONS & ANSWERS
1. The integrity of the subscapularis tendon can be tested by
a. The lift-off test
b. The Neer impingement test
c. The Hawkins test
d. Resisted external rotation
Answer: a
Explanation: The Neer impingement test and Hawkins tests both test for nonspecific impingement. Resisted external rotation would give you information about the integrity of the infraspinatous muscle.
2. The presence of unilateral periscapular muscle atrophy and weakness on physical examination
a. Suggests acute injury to the rotator cuff tendons
b. May indicate traumatic subacromial bursitis
c. Correlates with long-standing rotator cuff tendon tear
d. Should alert the examiner to look for pathology outside of the rotator cuff
Answer: c
Explanation: Not enough time has elapsed in order to see muscle atrophy in acute rotator cuff tendon damage, including traumatic subacromial bursitis, therefore, the presence of unilateral periscapular muscle atrophy is highly suggestive of a longstanding rotator cuff tear.