Single-position Lateral Lumbar Interbody Fusion and Percutaneous Pedicle Screw Fixation Allows for Adequate Correction of Spinal Sagittal Imbalance

Presented at SMISS Annual Forum 2016
By J. Thomas
With

Disclosures: J. Thomas B; Nuvasive Corporation

Atlantic Neurosurgical and Spine Specialists, Wilmington, NC

Introduction

Placement of bilateral pedicle screw fixation (PSF) in the lateral decubitus (LD) position after lateral lumbar interbody fusion is safe, reproducible and allows for improved operating room efficiency. One perceived limitation of this technique is that adequate correction of lumbar and segmental lordosis (LL and SL) may not be achieved without prone positioning.

Aims/Objectives

This study aims to demonstrate that prone positioning after lateral interbody fusion is not necessary to adequately correct spinal sagittal imbalance. 

Methods

A retrospective review of prospectively collected data was performed for adult patients who underwent extreme lateral or oblique lumbar interbody fusion (XLIF or OLIF) followed by placement of bilateral PSF placed either in the LD or prone position. Patient demographics, case times, and pre- and post-operative spinopelvic parameters were examined. Student’s T-test was used as appropriate. 

Results

42 patients underwent either XLIF or OLIF followed by bilateral percutaneous PSF from November 2015 through July 2016. Mean age was 58.4 in the LD group and 68.3 in the prone group. 162 screws were placed in 35 patients in the LD position (4.63 per patient) while 40 screws were placed in 7 patients in the prone position (6.67 per patient). Average number of levels in the LD group was 1.3 and was 2.6 in the prone group (p=0.07). Average case time was 103.2 minutes for LD patients and 182.7 minutes for prone patients (p=0.00). For those patients flipped prone the average flip time was 30 minutes. Baseline pelvic incidence-lumbar lordosis (PI-LL) mismatch was 8.1 in the LD group and 12.3 in the prone group (p=0.43). Mean improvement in PI-LL mismatch was 4.6 degrees in the LD group and 13.6 degrees in the prone group (p=0.09). Mean improvement in SL was 4.86 in the LD group and 6.75 degrees in the prone group (p=0.71). Mean improvement in LL was 4.86 in the LD group and 16.6 degrees in the prone group (p=0.05). When corrected for the number of levels performed the difference in LL correction was not statistically significant. There were no major complications. 

Conclusions

Placement of bilateral PSF with the patient remaining in the LD position after lateral lumbar interbody fusion is safe and efficient. Repositioning patients to a prone position did not afford any statistically significant increase in mean improvement of SL, LL or PI-LL mismatch. This single-position technique allows for adequate correction of sagittal balance without the need for prone positioning.