Anterior Lumbar Interbody Fusion in Left-sided Inferior Vena Cava and Right-sided Aortic Arch.

Spinal fusion via anterior lumbar interbody fusion (ALIF) can offer symptomatic relief to patients that suffer severe low back pain, radiculopathy, and claudication. However, a detailed working knowledge of the thoracic, abdominal, and lumbar anatomy, particularly of the vasculature, is vital. We report the case of a 68-year-old man who presented with radiculopathy and progressively worsening low back pain despite 9 months of unsuccessful conservative therapy and pain management. Preoperative computed tomography and magnetic resonance imaging revealed a rare anatomical variation, with an anomalous left-sided inferior vena cava and anomalous aorta. The patient was surgically treated with ALIF at L4,5 and L5 S1 via an altered surgical window. Given the anomalous anatomy of the patient, instead of performing the procedure after mobilizing both of the transposed abdominal great vessels, the inferior vena cava and the abdominal aorta, the ALIF was uneventfully performed in the window between these vessels. There were no perioperative or postoperative complications. At 12-week postoperative follow-up, X-ray imaging demonstrated successful implantation of ALIF cages with no recurrence of symptoms. A detailed working knowledge of anatomy is important, particularly if anatomical variations are present. This has implications for preoperative surgical planning, which is integral to the safety and the success of procedures.