Abstract
We evaluated the findings of MR imaging of patients with subacromial impingement syndrome.
We took MR images of 51 patients with subacromial impingement syndrome and examined their high signal intensities of the subacromial bursa, the subdeltoid bursa, and the glenohumeral joint, their cystic changes in the greater tuberosity, their high signal intensity in the rotator cuff, the acromiohumeral interval, and the shapes of the acromion.
A high signal intensity of the subacromial bursa was found in 68.6%. A high signal intensity of the subdeltoid bursa was found in 15.7%. A high signal intensity of the glenohumeral joint was found in 31.4%. Cystic changes in the greater tuberosity was found in 51.0%. A high signal intensity in the rotator cuff (an incomplete tear of the rotator cuff) was found in 45.1%. The acromiohumeral interval was 9.69mm (average). The shapes were flat type of the acromion 43.9%, smooth curve type 41.5%, and anterior hook type 14.6%.
Statistically there is a close relation between the high signal intensities in the rotator cuff on the bursal side and the cystic changes in the greater tuberosity.
The acromiohumeral interval of patients with subacromial impingement syndrome was within the normal limit. Anterior hook type was the fewest of the three types. So“supraspinatus outlet impingement”(written by Neer) was thought to be few.
