An iatrogenic popliteal pseudoaneurysm masked under compartment syndrome of leg.

This case describes a 60-year-old gentleman who presented with a pulsating mass behind his knee. Before this, he had a fasciotomy for suspected compartment syndrome of leg following knee arthroscopy, but this failed to resolve his leg symptoms. He was hemodynamically stable on presentation. His left calf was swollen with a circumference of 3 cm greater than right. There was a large pulsating mass palpable in his left popliteal fossa. Distal neurovascular status of the leg was intact. He had a normal cardiovascular, respiratory, abdominal and neurological examination. Ultrasound showed a cystic mass in the popliteal fossa suggestive of aneurysm. CT angiogram demonstrated a 6 × 5 × 4 cm pseudoaneurysm compressing and displacing the left popliteal artery with satisfactory three-vessel run-off. An emergency repair was performed. An arteriotomy was identified at the proximal end of pseudoaneurysm and it was closed with a patch of small saphenous vein. It led to a good clinical outcome.