Spontaneous Disappearance of an Acromioclavicular Joint Cyst: A Case Report

Abstract not available. Introduction provided instead.

Rotator cuff injuries are common. In most cases, the first symptom is shoulder pain, spinatus muscle atrophy, or inability to elevate or rotate the arm (or loss of strength in either action). An acromioclavicular (AC) joint cyst is a rare first symptom of a full-thickness rotator cuff tear.^1-9 This cyst can be observed as a variable-in-size swelling, above the AC joint, that is caused by synovial fluid.^1,2,6,8-12 In this report, we describe a case of an AC joint cyst on the right shoulder.