Ligamentum-preserved/temporary preserved minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar spondylolisthesis: technical note and two-years follow-up.

Study design Prospective study. Objective The aim of this study was to prospectively assess the clinical outcomes of modified MIS-TLIF for the treatment of single-segment lumbar spondylolisthesis. Summary of background data MIS-TLIF is a safe and effective procedure in the treatment of lumbar degenerative disease. To avoid durotomy and nerve root injury, we modified the surgical order of MIS-TLIF such that the interbody fusion procedure was performed before the decompression procedure. Methods One hundred thirty-nine patients with single-segment lumbar spondylolisthesis were separated into two groups. 67 patients underwent modified MIS-TLIF (group A). In group B, 72 patients underwent routine MIS-TLIF. The Japanese Orthopaedic Association (JOA) score and the visual analogue scale (VAS) scores for lower back pain (LBP) and leg pain were assessed during the postoperative follow-up, and the lumbar interbody fusion rate was evaluated by CT scanning. Results The mean operative time, incision length, average blood loss and incision pain level were not significantly different (P > 0.05) between the two groups. No nerve root or dural injuries were observed in group A. In group B, there were 2 cases of dural injury and 3 cases of nerve root injury. One patient experienced temporary numbness and weakness on dorsiflexion of the foot, which recovered in three months. No differences were identified between the two groups when postoperative JOA scores, back pain, leg pain VAS scores or the lumbar interbody fusion rate. Conclusion Both methods are effective in the treatment of lumbar degenerative disease. Modified MIS-TLIF is a safe and effective procedure that can significantly reduce the occurrence of injury to the dura and nerve root during decompression and the interbody fusion procedure.Level of Evidence: 3.