- Discussion:
- glenohumeral arthritis;
- look for the characteristic osteophyte at the inferior aspect of the humeral head;
- nerve palsy:
- w/ atrophy of both the supraspinatus and infraspinatus, consider obtaining an
MRI of the shoulder, to
evaluate for space occupying lesion causing
suprascapular nerve palsy;
- also consider
EMG:
- glenohumeral instability (either
recurrent anterior or
multidirectional)
- commonly mistaken for impingement syndrome in younger patients;
- w/ large labral detachement or tear, symptoms may be similar to impingement syndrome;
- positive apprehension sign will confirm the diagnosis;
- subacromial injection of lidocaine does not usually relieve symptoms relating to shoulder instability;
-
cervical spondylosis (radiculitis);
-
frozen shoulder (non outlet impingement)
- soft tissue contractures of frozen shoulder may cause translation of humeral head w/
attempted flexion which can result in impingement despite normal acromial anatomy;
- patients w/ contracture of the posterior capsule (and loss of internal rotation) will be most
likely to demonstrate signs of impingement (despite normal acromial anatomy);
-
AC joint arthritis;
- lidocaine injection into acromioclavicular joint distinguishes
this problem from impingement;
- paralysis of the
trapezius
- interarticular pathology, such as glenohumeral arthritis, presents w/
bony crepitus and greater limitations of passive motion;
- true AP & axillary view of glenohumeral joint will show arthritis;
-
calcific tendinitis:
- cuff tear arthropathy
-
biceps tendonitis
-
reflex sympathetic dystrophy
-
thoracic outlet syndrome
-
os acromiale:
