A sixteen-ear-old boy came to our hospital complaining of the prominence of bony mass with audible and palpable grating localized at the medial side of the right scapula. Regular anteroposterior and tangential view of the scapula showed a bony mass on the sixth rib. At operation, there was an inflamed bursa containing bloody fluid between the scap ula and the sixth rib. The tumor was removed from the right sixth rib. Histological examination showed it to be an osteochondroma.
Snapping scapula (scapulothoracic syndrome) is a relatively common clincal condition. It may be attributed to two underlying causes: (1) changes in the interposed soft tissues, the muscles, and the bursae between the scapula and the chest wall and (2) changes in the congruence between anterior scapular surface and underlying chest wall.
The snapping scapula of this case was due to the projection of an exostosis of the right sixth rib and the inflamed bursae between the scapula and exostosis.
