Osteochondroma is a cartilage-capped bony projection arising from the external surface of bone and accounts for approximately 20–50% of all benign bone tumours ^[1,2,3]. Scapular osteochondromas represent a small proportion of shoulder girdle tumours ^[1,4]. Most lesions arise from the anterior surface and present earlier due to scapulothoracic impingement or snapping scapula syndrome ^[4,5].

A 6-year-old male child presented with a swelling over the left upper back, first noticed at 6 months of age. The swelling gradually increased in size over the past year, with recent pain and restriction of shoulder movements.

Clinical examination: 

A solitary, well-defined bony swelling measuring 9 × 6 × 4 cm was noted over the medial aspect of the spine of the left scapula (Fig. 1). It was non-tender, bony hard, and moved with scapular movements.

Radiological findings: 

Plain radiographs showed a well-defined exophytic lesion with cortical and medullary continuity and a thin cartilage cap measuring 2.5 mm. Magnetic resonance imaging revealed a well-defined heterointense exophytic lesion arising from the posterior margin of the left scapula at the junction of the body and spine, with no evidence of infiltration and a thin cartilage cap measuring approximately 2.5 mm (Fig. 2).

Surgical management: 

Complete excision was performed through a posterior approach. Post-operative radiographs confirmed complete removal (Fig. 3).

Histopathology: 

Sections showed mature hyaline cartilage cap with endochondral ossification and underlying trabecular bone (Fig. 4). No malignant features were noted.

Scapular osteochondromas are clinically significant, as they may disrupt scapulothoracic rhythm ^[2,5]. Flat bones such as the scapula have a relatively higher risk of malignant transformation ^[6]. The risk of malignant transformation, although low, has been well documented in literature ^[7,8]. Surgical excision is recommended for symptomatic lesions with good functional outcomes ^[9,10].

Posterior scapular osteochondroma in paediatric patients is rare. Awareness and timely surgical management lead to excellent outcomes.

Posterior scapular osteochondroma should be considered in children presenting with dorsal scapular swellings.