Wednesday, September 26, 2018 10:35 AM – 12:00 PM Understanding Lumbar Stenosis/Spondylolisthesis: 15. Decreased operative time and estimated blood loss in lateral trans psoas versus anterior approach to lumbar interbody fusion for degenerative spondylolisthesis

Abstract

BACKGROUND CONTEXT The lateral trans psoas approach was introduced as a less-invasive alternative with potentially accelerated postoperative recovery relative to the traditional anterior approach to lumbar interbody fusion. Lumbar fusion through the lateral trans psoas approach is associated with low estimated blood loss, improvement in postoperative patient reported outcomes, and low complication rates, but is also associated with exposure-related sensory and motor changes in the ipsilateral lower extremity. Both anterior and lateral trans psoas approaches for single level fusions at any lumbar segment yield similar complication rates, radiographic and early clinical outcomes. There is, however, a paucity of literature specifically comparing anterior lumbar interbody fusion with lateral trans psoas for degenerative spondylolisthesis. PURPOSE The goal of the study was to compare outcomes of lateral trans psoas versus anterior approaches to lumbar interbody fusion for single level degenerative spondylolisthesis. The hypothesis is that lateral trans psoas lumbar interbody fusion for degenerative spondylolisthesis results in less estimated blood loss and operative time as well as similar postoperative patient-reported outcomes, without increasing complications rates, compared to anterior lumbar interbody fusion. STUDY DESIGN/SETTING The study was a retrospective cohort of consecutive patients undergoing single-level interbody fusion for L4-5 degenerative spondylolisthesis via anterior retroperitoneal or lateral trans psoas approach between 2008 and 2012 at a single academic center. PATIENT SAMPLE Patients undergoing lumbar interbody fusion at the L4-5 level for degenerative spondylolisthesis at a single academic center. OUTCOME MEASURES Differences in patient demographics, peri-operative data (estimated blood loss, operative time, adjunct procedures or additional implants), 30-day complications (infection, DVT/PE, weakness/paresthesia, etc.), and patient reported outcomes (leg and back Numerical Rating Scale, and Oswestry Disability Index) were assessed. METHODS Differences between groups were assessed with chi-squared or Fisher's exact tests, with a two-sided level of significance of α=0.05. Mean and 95% confidence intervals (CI) were reported for normally distributed variables, versus median and interquartile range (IQR) for non-normally distributed variables, RESULTS Both estimated blood loss during surgery (median 100 ml, IQR 50-100 ml) and operative time (241 minutes, CI 209-273 minutes) were significantly less for lateral trans psoas approach than for anterior approach (median 250 ml, IQR 150-400 p CONCLUSIONS The lateral trans psoas approach is associated with diminished blood loss and operative time compared to the anterior approach, without an increase in complication rates or difference in patient reported outcomes. Continued efforts to directly compare approaches for specific indications will minimize complications and improve outcomes. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.