bursitis, greater tuberosity fracture, and adhesive capsulitis. However, MRI provides more information about adjacent structures in the shoulder such as the capsule, glenoid labrum muscles and bone and these factors should be considered in each case when selecting the appropriate study. Xray X-ray projectional radiography cannot directly reveal tears of the rotator cuff, a 'soft tissue', and consequently, normal X-rays cannot exclude a damaged cuff. However, indirect evidence of pathology may be seen in instances where one or more of the tendons have undergone degenerative calcification (calcific tendinitis). The humeral head may migrate upwards (high-riding humeral head) secondary to tears of the infraspinatus, or combined tears of the supraspinatus and infraspinatus. The migration can be measured by the distance between: A line crossing the center of a line between the superior and inferior rims of the glenoid articular surface (blue in image). The center of a "best-fit" circle positioned over the humeral articular surface (green in image) Normally, the former is positioned inferiorly to the latter, and a reversal is therefore indicating a rotator cuff tear. Prolonged contact between a high-riding humeral head and the acromion above it, may lead to X-rays findings of wear on the humeral head and acromion and secondary degenerative arthritis of the glenohumeral joint (the ball and socket joint of the shoulder), called cuff arthropathy, may follow. Incidental X-ray findings of bone spurs at the adjacent acromioclavicular joint may show a bone spur growing from the outer edge of the clavicle downwards towards the rotator cuff. Spurs may also be seen on the underside of the acromion, once thought to cause direct fraying of the rotator cuff from contact friction, a concept currently regarded as controversial. In-office testing As part of clinical decision-making, a simple, minimally invasive, in-office procedure may be performed, the rotator cuff impingement test. A small amount of a local anesthetic and an injectable corticosteroid are injected into the subacromial space to block pain and to provide anti-inflammatory relief. If pain disappears and shoulder function remains good, no further testing is pursued. The test helps to confirm that the pain arises from the shoulder primarily rather than referred from the neck, heart, or gut. If pain is relieved, the test is considered positive for rotator-cuff impingement, of which tendinitis and bursitis are major causes. However, partial rotator-cuff tears may also demonstrate good pain relief, so a positive response cannot rule out a