Aberrant iliac artery: far lateral lumbosacral surgical anatomy

A 44-year-old man presented after 3 weeks of progressively worsening atraumatic onset pain in the right anteromedial thigh. The pain was sharp and radiated to the anteromedial shin and medial foot. The patient had no associated weakness, numbness, or bowel/bladder dysfunction. Nonsteroidal anti-inflammatory, pain, and neuropathic-relieving drugs had limited effect. He underwent interlaminar injections, which provided transient relief of his shin symptoms. After conservative management failed, a spine surgeon (not affiliated with our practice) recommended an anterior lumbar interbody fusion via far lateral approach. The patient presented to our spine clinic for a second opinion. Closed magnetic resonance imaging revealed an aberrant iliac artery impinging on the lumbar plexus and a foraminal herniation at L4-L5 on the right, an orientation more lateral than expected or seen on the contralateral side. We recommended physical therapy that focused on core strength and adequate stretching prior to considering surgery. The patient's symptoms have since resolved. Common iliac artery anomalies are rare. No known incidence exists. The finding in this case was incidental and, if missed, could have led to vascular compromise. To prevent such an injury during minimally invasive (transpsoas lateral approach) spine surgery, we recommend careful examination of radiographs for aberrant vessels.