- Stage I:
- edema and hemorrhage:
- reversible lesion usually seen in the second and third decade;
- exam:
- palpable tenderness over the greater tuberosity at supraspinitus insertion
- palpalble tenderness along the anterior edge of the acromion;
- painful arc of abduction between 60 and 120 deg increased with resistance at 90 deg;
- Stage II:
- chronic inflammation or repeated episodes of impingement leads to fibrosis & thickening of supraspinatus, biceps, & subacromion bursa;
- at this stage there is inability to reverse process by activity modification;
- generally pts are between 25-40 years, however, age is less important than the duration of symptoms, which is usually years;
- symptoms consist of an aching discomfort, often interfering w/ sleep & work, and may progress to interfere w/ activities of daily living
- mild limitation to both passive and active range of motion;
- arthroscopic acromioplasty & subacromial decompression do not require deltoid detachment & are assoc w/ cost savings & more rapid rehab;
- arthroscopic acromioplasty is perhaps most suited for type II lesions (w/ partial tears), and is less useful for those with no tears or complete tears;
- Stage III:
- rotator cuff tears, biceps ruptures, and bone changes;
- following a prolonged history of refractory tendinitis, significant tendon degeneration is the hallmark of stage 3;
- pts are usually in the 5th or 6th decade, and often admit to prolonged periods of pain, particularly at night;
- weakness can be bothersome;
- as further rotator cuff degeneration occurs:
- limitation to shoulder motion;
- infraspinatus atrophy;
- weakness of shoulder abduction and external rotation;
- biceps tendon involvement with rupture or degenerative changes occuring in a high percentage of pts with rotator cuff tears;
- AC joint tenderness, esp if degenerative changes are present;
- although pain related weakness can be present at any stage, injection of 1% lidocaine within the subacromial space in Stage 3 will not eliminate weakness and limitation of active motion;
- radiographic changes:
- cystic changes about the greater tuberosity
- sclerotic changes beneath the anterior third of the acromion;
- osteophytes along the undersurface of acromion often associated with the coracoacromial ligament;
- AC joint changes;
- late narrowing of the subacromial space
Impingement syndrome in the absence of rotator cuff tear (stages 1 and 2).