Background: Many osteochondromas are asymptomatic and are incidentally discovered on radiography.
Asymptomatic lesions require no treatment. Tumours with pain secondary to muscle irritation,
vascular compression, and malign degeneration require surgical excision.
Case Report: A 21-year-old man presented abdominal distension since several months accompanied by
occasionally nausea and vomiting. There were also mild haematuria. Bowel sounds were presented on abdominal examination. At abdominal palpation, a large fixed mass at the left iliac crest was evidenced. There was no rebound tenderness.
At abdominal x-ray revealed a bone mass originating from the left iliac crest. Abdominal MRI
was suggestive for an osteochondroma. The mass was measured 10,0 x 9,5 cm in greatest dimension and the thickness of the cartilaginous cape was less than 2 milimeters. The patient underwent excisional biopsy of the bone lesion. Histopathology confirmed the diagnosis of osteochondroma. Recovery was uneventful at one year without recurrence of the tumour.
Conclusions: Osteochondroma of iliac bone is a rare tumor especially in the inner region of the bone, which can cause abdominal symptoms.

Keywords: Osteochondroma, bone tumour