Does indirect decompression by oblique lateral interbody fusion produce similar clinical and radiological outcomes to direct decompression by open transforaminal lumbar interbody fusion

Objectives: Open transforaminal lumbar interbody fusion (O-TLIF) remains the most popular and widely practiced lumbar fusion method even today, providing direct decompression. Oblique lateral interbody fusion (OLIF) is a novel retroperitoneal approach that allows placement of a large interbody cage which provides an indirect neural decompression, and screws can be placed minimal invasively or through the Wiltse OLIF (W-OLIF) approach. We aim to find out the short-term efficacy of W-OLIF to O-TLIF in terms of radiological and clinical outcomes in patients of lumbar degenerative diseases. Materials and Methods: Fifty-two patients were divided equally into two groups (group O-TLIF and group W-OLIF). Several parameters were measured, such as the spinal cord cross-sectional area (SC-CSA), foraminal cross-sectional area (F-CSA), disc height (DH), foraminal height (FH), Schizas grade for stenosis, and Meyerding’s grading for olisthesis. Functional scores were measured using the visual analog scale (VAS) for low back pain (LBP) and lower limbs, Oswestry Disability Index. All parameters were repeat measured at 3 months follow-up. Statistical analysis was done using SPSS software. Results: Both groups were similar in composition preoperatively. There was significant improvement in all clinical and radiological parameters post-surgery in either group. However, at 3 months, The DH, FH, FSA, and VAS (LBP) were better in the W-OLIF group than in O-TLIF. Procedure-related complications were seen in both groups (15% in the O-TLIF group and 19% in the W-TLIF group), but only one patient in O-TLIF required revision due to cage migration. Conclusion: Similar improvement occurs in most of the clinical and radiological parameters in the W-OLIF group compared to the O-TLIF group. Few radiological parameters such as the DH, FH, and F-CSA and the VAS (LBP) correction are superior in the W-OLIF group in the short-term follow-up. We conclude that indirect decompression by W-OLIF provides equivalent, if not better, results than the traditional O-TLIF lumbar fusion.