133 - Nerve Protection in Extreme Lateral Interbody Fusion...

#133 Nerve Protection in Extreme Lateral Interbody Fusion

MIS Techniques and Outcomes

Poster Presented by: F.G. Diaz

Author(s):

F.G. Diaz (1)
C.R. Cook (2)
R. Tyo (2)

(1) Michigan Head and Spine, Southfield, MI, United States
(2) DC2 Healthcare, Nashville, TN, United States

Abstract

Introduction: Extreme lateral interbody fusion (XLIF) has revolutionized the approach to the anterior lumbar spine by providing a direct access to the intervertebral space at any level of the lumbar spine above L5-S1. The need for an access surgeon to reach the anterior lumbar surface has virtually disappeared. It is necessary for the spine surgeon who performs XLIF surgery to be aware of the distinct neurological variability that exist at the different levels of the lumbar spine, and how to protect the nerves to prevent significant post-operative neurological complications.

Material and Method: Preoperative thin section multiplanar CT scanning facilitates the clear identification of the plexus within the body of the iliopsoas muscle, and allows the surgeon to precisely determine preoperatively the location of the nerves in relation to the lateral surface of the vertebral bodies at the level where the XLIF will be performed. 213 XLIF procedures have been performed in 150 patients at multiple levels. 120 levels were done using conventional EMR without CT assistance in the localization of the plexus, and 93 were done using the combination of EMR and CT localization.

Results: CT localization and guidance allowed the surgeon to precisely locate the nerves with EMG prior to their retraction in every patient using the CT/MRI method, and permitted the dissection away from the retractor placement with protection of the lumbar plexus. Postoperative paresthesias and iliopsoas muscle weakness developed in 40 patients using EMR guidance only, and lasted for up to six months. In patients who had CT/MRI guidance paresthesias developed in five patients, and iliopsoas weakness occurred in two; the paresthesias resolved in two months, and the muscle weakness in three weeks.

Conclusions: MRI/CT guidance allows the spine surgeon to locate the lumbar plexus preoperatively, and permits its safe dissection and protection during surgery.