Surgical anatomy of the minimally invasive lateral lumbar approach

The lateral lumbar interbody fusion approach (LLIF), which encompasses the extreme lateral interbody fusion or direct lateral interbody fusion techniques, has gained popularity as an alternative to traditional posterior approaches. With rapidly expanding applications, this minimally invasive surgery (MIS) approach is now utilized in basic degenerative pathologies as well as complex lumbar degenerative deformities and tumors. Given the intimate relationship of the psoas muscle, and hence the lumbar plexus, to this MIS approach, several authors have examined the surgical anatomy of this approach. Understanding this regional neural anatomy is imperative given the potential for serious injuries to both the motor and sensory nerves of the lumbar plexus. In this review, we critically and comprehensively discuss all published studies detailing the surgical anatomy of the lateral lumbar approach with respect to the MIS LLIF techniques. This is a timely review given the rapidly growing number of surgeons utilizing this technique.