A rare presentation site for osteochondroma scapula and pelvis, intramembranous ossifying bones of axial skeleton: case series

Abstract

Osteochondroma is the most common primary bone tumour comprising over 33% of benign bone tumours. The formation of osteochondroma occurs because of exophytic protuberance on the surface of growing bones. The most common sites for osteochondroma are the distal femur, proximal tibia, and proximal humerus. We are presenting a case series of three patients with rare presentation sites of osteochondroma, scapula and pelvis. Osteochondroma is primarily disease of appendicular skeleton but we are reporting it in axial skeleton. Radiographic findings include fluffy cartilaginous outgrowth arising from the external surface of a long tubular bone that may be pedunculated or sessile. Osteochondromas usually develop in bones that develop by enchondral ossification and rarely develop in bones developing by intramembranous ossification like pelvis. These tumours are usually asymptomatic but can cause pubic visceral compression or neurovascular compromise by compressing external and internal iliac vessels and lumbosacral pluxes. Scapular osteochondroma can cause compression or neurovascular compromise in thoracic cavity and axillary vessels and brachial pluxes. Treatment with surgical excision gives consistent results and relief of pain.