A vestige of an extra upper-limb skeleton in the left shoulder

摘要

A 31-year-old woman was unable to flex or abduct the left shoulder beyond 90°. She sometimes experienced a dull ache around the shoulder. Internal and external rotation of the shoulder was normal. There was no cosmetic defect and the shoulder region had a normal contour. The body of the left scapula had normal borders and a normal position on the chest wall. It was level and symmetrical with the right scapula. The left trapezius muscle was mildly atrophic. The left elbow and hand and the right shoulder were normal. On palpation there was a hard structure in the anterolateral section of the deltoid muscle. It was attached to the acromion and did not have independent movement. There were no other musculoskeletal orvisceral abnormalities.