Visit our site
— ABIBLO.COM (@ABILBO3) August 31, 2019
0 Comments
Are there any special maneuvers that can be used for testing impingement?
The Neer (impingement) test and the Hawkins-Kennedy test. Both cause the supraspinatus tendons to rub against the acromion, thus eliciting pain in cases of impingement. Still, beware that it is usually very difficult to clinically identify the location of the problem, that is, to separate bursitis from tendinitis or even partial rotator cuff tears injection: local anesthetic and steroids injected into the bursa will relieve bursitis but not tendinitis nor partial rotator cuff tear. How do you examine for shoulder impingement? (1) By palpating the subacromial space (which elicits pain in patients with bursitis/tendinitis), and (2) by assessing the shoulder girdle muscles, especially during external/internal rotation and abduction. Supraspinatus problems can be identified by the empty can test, also described by Jobe, and so named because the patient’s position is similar to that assumed when emptying a can. To carry this out, have the patients (1) abduct the shoulder to 90 degrees and forward flex it at 30 degrees and (2) fully rotate the upper extremity (so that the thumbs are pointing toward the floor). While they do so, instruct them to forward flex the shoulder while you are applying resistance from behind. Patients with supraspinatus tendinitis or partial injury to the tendon will experience pain. Those with a partial- or full-thickness tear will be instead unable to achieve any forward flexion.
What are the symptoms of shoulder impingement?
The initial one is pain—aching and gradual (acute and tearing suggest instead a rotator cuff tear), centered around the anterior-superior-lateral aspect of the shoulder, and occasionally referred to the deltoid region. Pain interferes with sleep (especially when the patient rolls onto the affected shoulder) and is exacerbated by lateral or anterior raising of the arm and by forward flexion and internal rotation of the humerus (as if trying to reach into a back pocket). Pain worsens with time, and the joint may become stiff, causing “catching” sensations upon lowering of the arm. Weakness and inability to raise the arm suggest instead a rotator cuff tear. What is the “drop arm” test?
A good way to identify rotator cuff pathology. Ask patient to raise the extended arms to a complete overhead abduction. Those with rotator cuff tear will be unable to smoothly bring the arms down to the sides from their abducted position. In fact, they may even display a cogwheel effect. How do you diagnose rotator cuff tendinitis?
By carefully examining the shoulder and by knowing the function of the four rotator cuff muscles (i.e., abduction, external rotation, and internal rotation). The supraspinatus is the most important and most commonly damaged of the four. It links the top of the scapula to the humerus, inserting into its greater tuberosity. It is partially responsible for arm abduction (the initial 15–30 degrees are actually produced by the deltoid, the next 60 degrees by the supraspinatus, and the final 90 degrees by the deltoid again). Hence, inflammation of the supraspinatus tendon leads to pain at 30–90 degrees of abduction, as the humerus impinges the tendon against the acromion. It can be easily tested through the empty can test. The infraspinatus produces external rotation of the humerus, a function assisted by the teres minor. The two also cooperate to maintain glenohumeral stability. To test external rotators (infraspinatus and teres minor): (1) have the patient abduct both shoulders to 20–30 degrees, while keeping the elbows flexed at 90 degrees; (2) instruct the patient to push the arms outward (externally rotate) against resistance. External rotation elicits pain in tendinitis and weakness in tears. The subscapularis is the only of the four rotator muscles to originate from the anterior surface of the scapula (the others arise instead in the back). It connects the scapula to the humerus, serving as humeral head depressor and, in certain shoulder positions (adduction), as internal rotator. Function is evaluated through the “Gerber’s lift-off test”: (1) have patients place the hand behind the back, with palm facing out, and (2) instruct them to lift the hand away from the back and against resistance. Internal rotation elicits pain in tendinitis and weakness in tears. Note that given the anatomic closeness of the long head tendon of the biceps (which passes down the bicipital groove in a fibrous sheath between the subscapularis and supraspinatus tendons), patients with rotator cuff disease also may have biceps tendinitis What is the cause of shoulder impingement?
Mechanical wear and tear. True tear of the cuff is actually a problem of older subjects, whereas rotator cuff disease and impingement tend to affect primarily laborers (whose job requires repetitive and protracted overhead activity) or young athletes (whose sport also involves repetitive overhead motions, such as throwing, swimming, volleyball, and tennis and other racquetplaying activities). Raising the arm over the shoulder forces the humerus against the edge of the acromion. Usually, there is enough room between the acromion and rotator cuff to allow the tendons to slide easily underneath the bone while the arm is being elevated. Recurrent arm-raising, however, eventually creates impingement (i.e., friction on the subacromial bursa and the distal part of the tendon). With time, this causes irritation and swelling of the bursa (bursitis), further narrowing the space between the acromion and rotator cuff. As a result, impingement on the tendon becomes more severe, which is risky since its blood supply is limited. Hence, the resulting tendinitis and, ultimately, the degenerative damage. Bony spurs of the acromioclavicular (AC) joint (which sits directly above bursa and rotator cuff tendons) may further narrow the subacromial space, and so can abnormal acromial morphology (such as a hooked acromion). What is shoulder impingement?
A concept first introduced by Neer in 1972 to describe mechanical impingement of the rotator cuff tendon. This runs above the humeral head and glenoid, and below the acromial process, coracoacromial ligament, and acromioclavicular joint. Recurrent friction causes bursitis, tendinitis, and ultimately, tendon degeneration and tearing. What is the “Popeye” sign?
A sign of rupture of the long head of the biceps tendon. The patient reports a sudden, painful, and audible snap, associated with (1) retraction of the biceps belly toward the elbow and (2) bulging over the anterior upper arm —as in the cartoon character “Popeye.” In the elderly, this may occasionally result from trauma. Otherwise, it is usually due to long-standing tendinitis. Hence, it is preceded by a long history of shoulder pain, quickly resolving with a painful snap. |