Comparison of biportal endoscopic vs minimally invasive transforaminal lumbar interbody fusion for single-level low-grade lumbar spondylolisthesis: A retrospective cohort study

Figure 2 Participant flow diagram. A total of 81 patients with lumbar spondylolisthesis who underwent surgery between December 2020 and December 2022 were screened. Eighteen patients were excluded according to the prespecified exclusion criteria: 11 with spondylolisthesis involving ≥ 2 levels, 3 with associated kyphosis, and 4 with associated cauda equina syndrome or spinal trauma, tumor, or infection. The remaining 63 patients were enrolled and allocated to the biportal endoscopic transforaminal lumbar interbody fusion group (n = 32) or the minimally invasive transforaminal lumbar interbody fusion group (n = 31). All patients completed the follow‑up and were included in the final analysis. BE-TLIF: Biportal endoscopic transforaminal lumbar interbody fusion; MI-TLIF: Minimally invasive transforaminal lumbar interbody fusion.