Snapping scapula caused by abnormal angulation of the superior angle of the scapula

Abstract

Snapping scapula (crepitus between the scapula and the chest wall) is not a rare condition; however, it only occasionally becomes painful and disabling. Boinet1 first described a case of snapping scapula in 1867. The etiology of snapping scapula is classified into two categories: skeletal or soft-tissue abnormalities.2,5-7 Skeletal abnormalities include varied conditions that lead to scapulothoracic incongruity, such as bone tumors of the scapula or ribs (osteochondromas or exostoses), abnormal anterior angulation of the superior angle of the scapula, Luschka's tubercle, bony prominence of the scapula, omovertebral bone, and malunion after fractures of the scapula or ribs. However, in some cases previously reported,2,11 it was difficult to find obvious skeletal abnormalities and the clear cause of the symptoms was unknown. There have been many reports that mostly revealed good results of surgical treatment for snapping scapula;2,3,5-10 however, it is still controversial whether operative treatment is necessary.11