P14. Comparative effectiveness of expandable versus static lateral lumbar interbody fusion devices: two-year clinical and radiographic outcomes

BACKGROUND CONTEXT Minimally invasive (MIS) lateral lumbar interbody fusion (LLIF) procedures using large interbody static spacers may require excessive trialing and forceful impaction, leading to iatrogenic endplate disruption, excessive neural retraction and implant subsidence. The in situ expansion capability offered by expandable interbody spacers facilitates insertion to help reduce endplate damage and optimize endplate contact. PURPOSE This study reported radiographic and clinical outcomes of static and expandable interbody spacers following MIS LLIF, and device-related complications including implant subsidence. STUDY DESIGN/SETTING Prospective clinical study. PATIENT SAMPLE This study included 48 patients with degenerative disc disease who underwent MIS LLIF at 1-2 contiguous level(s) using a polyether-ether-ketone static or titanium expandable intervertebral spacer. Twenty-one patients were treated with static spacers, and 27 with expandable spacers. OUTCOME MEASURES Operative time, blood loss, length of hospital stay, visual analog scale (VAS) pain scores, Oswestry disability index (ODI), RAND 36-item survey, disc height, subsidence rates. METHODS Clinical and radiographic outcomes were analyzed at 12 and 24 months postoperatively. RESULTS Mean patient age was 66.6±9.7 years, 72.9% of patients were female. No significant differences were observed between static and expandable groups in operative time (64.0±39.2min, 73.7±39.7min), estimated blood loss (35.6±29.2cc, 40.0±30.8cc), or length of hospital stay (2.0±1.3days, 2.4±1.3days), respectively (p CONCLUSIONS In this cohort, clinical use of expandable interbody spacers resulted in better outcomes through 24-month follow-up compared to static interbody spacers, with expandable group showing significant improvements in pain and disability than the static group at 24 months. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.