Enchondroma of acromion: case report of an unusual tumor location

Abstract

Enchondroma is a benign cartilaginous tumor and is rarely located on the shoulder girdle. The lesion that affects the subacromial area can cause rotator cuff impingement’s clinical signs. Our aim is to present this patient who has shoulder pain and was finally diagnosed with an acromial enchondroma. A 62-year-old female patient had an insidious left shoulder pain in the last 2 years. At the physical examination of the left shoulder, subacromial impingement syndrome’s sign was noticed. Plain radiographs didn’t have any typical features and magnetic resonance imaging (MRI) images were used for diagnosis. Well-circumscribed hypointense content on T1-weighted images was observed, and the lesion was seen as hyperintense on T2-weighted images. At the same time, subacromial effusion was noticed. Because of enchondroma’s small size, the patient was followed up with medical treatment and radiographical features. At one year follow-up, there was no change in the size of the lesion and no increased complaint about her left shoulder. Physicians should keep in mind that enchondroma may occur rarely in acromion and this condition may cause subacromial impingement. Therewithal, this diagnosis which is a rare reason for subacromial impingement syndrome should be considered in the differential diagnosis of shoulder pain.

Keywords

• Enchondroma
• neoplasm
• acromion
• shoulder
• impingement

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