Female Sex and Supine Proximal Lumbar Lordosis Are Associated With the Size of the LLIF "Safe Zone" at L4-L5.

Study Design: Retrospective chart review.

Objective: Identify demographic and sagittal alignment parameters that are independently associated with femoral nerve position at the L4-L5 disk space.

Summary Of Background Data: Iatrogenic femoral nerve or lumbar plexus injury during lateral lumbar interbody fusion (LLIF) can result in neurological complications.