Femoral Artery Pseudoaneurysm Caused by an Osteochondroma of the Femur: A Case Report

Abstract

Introduction The osteochondroma is the most common benign tumor of bone. Typically asymptomatic bony protuberances are discovered in childhood or adolescence. Although vascular complications are rare, these bony spikes can course along an artery and cause severe arterial complications. Reported here is a case involving the use of color duplex ultrasonography (CDU) to identify a superficial femoral artery (SFA) pseudoaneurysm as a result of an osteochondroma. Case Report A 12-year-old girl had been experiencing left lower extremity pain for approximately 2 months. The pain became progressively severe, and her parents noticed that she was limping. Magnetic resonance imaging (MRI) demonstrated a mass in the left thigh, suggesting the possibility of a femoral aneurysm. A bony spicule was noted on x-ray at the distal femur, projecting posteriorly. Clinical evaluation revealed an impressive pulsatile mass in the left distal medial thigh. The left thigh was noticeably larger than the right with poor pedal pulses compared with the asymptomatic limb. CDU was performed and identified an aneurysm of the SFA at the adductor canal. There was unusual oscillatory flow in the SFA proximal to the aneurysm with monophasic signals distally. The large aneurysm size displaced the normal anatomic course of the SFA and vein. Ankle-brachial indices (ABI) were 0.72 and monophasic in the affected limb and >1.0 and triphasic in the contralateral limb. Angiography confirmed the CDU and MRA findings, demonstrating a large pseudoaneurysm at the adductor canal caused by an osteochondroma of the femur. At time of surgical repair, the bony spicule was noted to have eroded into the femoral artery. Conclusion Vascular complications as a result of an osteochondroma are rare. Rapid diagnosis is necessary to prevent serious arterial compromise in these young patients. CDU can quickly and accurately confirm the presence of a pseudoaneurysm when an osteochondroma is suspected.