Femoral nerve palsy secondary to traumatic pseudoaneurysm and iliacus hematoma

The authors report a case of traumatic femoral nerve palsy caused by a pseudoaneurysm of the iliolumbar artery and a iliacus muscle hematoma. This case report details not only the classic history and physical findings seen in patients such as this one, but also illustrates an unusual source of the hematoma and a discussion of its treatment. A 20-year-old man was assaulted and presented to the authors's institution with a 1-week history of severe pain in the left anterior thigh and groin, weakness in the left quadriceps muscle, and numbness in the anterior thigh and medial distal leg. Imaging studies demonstrated a large, 9.4 x 6.4 x 5.2-cm iliacus hematoma as well as a pseudoaneurysm originating from the left iliolumbar artery. The patient underwent angiographic embolization of the pseudoaneurysm followed by surgical evacuation of the hematoma. The embolization was performed before surgery to prevent any possible rebleeding from the pseudoaneurysm during evacuation of the hematoma. Femoral nerve palsy caused by traumatic iliacus hematoma is an infrequent diagnosis often missed because of its insidious presentation. In this case, embolization of the iliolumbar artery pseudoaneurysm followed by surgical evacuation of the hematoma resulted in a nearly full recovery of the femoral nerve as of the last follow-up examination.