Technical description and single institution retrospective case series.

Evaluate technical feasibility and evaluate complications of mini-open retroperitoneal oblique lumbar interbody fusion (OLIF) at the L5–S1 level.

The mini-open retroperitoneal oblique lumbar interbody fusion (OLIF) approach was first described in 2012 as a surgical approach to achieve spinal fusion while limiting invasiveness of the exposure to the anterior lumbar spine. Surgeons who use this approach, along with those who described it in cadaveric studies describe it as a feasible approach in targeting the L2 down to the L5 level and recommend alternative approaches to the L5–S1 level due to the vascular challenges and possible complications.

Technical description and single institution case series of patients treated with the OLIF between 2013 and 2015 at the L5–S1 level. The previously described surgical approach was modified by identifying and ligating the iliolumbar vein before retracting the iliac artery and vein anteriorly instead of passing between the vessels.

Six patients (3 males, 3 females, mean age 62 years) were operated between 2013 and 2015. There were no vascular injuries or peripheral nerve trauma associated with the surgical procedure. Complications associated with the procedure included: cage displacement immediately postoperative requiring re-operation in one patient, transient psoas weakness in one patient, extended hospital stay for pain control in one patient, and transfusion was required in one patient.

Mini-open retroperitoneal oblique lumbar interbody fusion is feasible at the L5–S1 level with limited vascular complications through a technical modification for safe mobilization of the iliac vessels by first ligating the iliolumbar vein.