Introduction: Osteochondromas are benign bone tumors. They can be asymptomatic or damage adjacent structures and and can cause various types of complications among them pseudo aneurysms, which are uncommon consequences of this pathologic osseous growth. The advent of new radiologic modalities has allowed for early diagnostics and treatment of these entities.

Case Report: We report the case of a 29-year-old female, with no history of chronic disease, who consulted for a throbbing sensation behind the knee and a lump mass in the popliteal fossa. We conducted a doppler ultrasound and a CT-angiography, which demonstrated a popliteal artery aneurysm complicating an osteochondroma. A surgery, was done with no complication in the 24 months follow-up.

Conclusion: Early diagnosis followed by surgical resection is the mainstay of management popliteal artery aneurysm complicating osteochondromas. CT angiography is the modality of choice for the detection and evaluation of osteochondromas vascular complications.

Keywords: Bone exostosis, Computed tomography, Popliteal artery, Pseudo aneurysm, Ultrasound