Minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) in treatment of degenerative diseases of lumbosacral spine compared to modified open TLIF: a prospective randomised controlled study.

Introduction: The aim of this study was to determine the clinical and radiological outcomes of minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) compared to modified open TLIF via the Wiltse approach for treatment of degenerative diseases of the lumbosacral region. The results were evaluated over a post-operative period of 48 months.

Material and method: Radiological data and medical records of patients who underwent MIS TLIF and modified open TLIF between May 2017 and May 2021 were reviewed. Parameters monitored to evaluate the surgical results were: clinical status, operation time, blood loss, radiation dose to patient, day of discharge, analgesic consumption, fusion, and complications rate. For functional assessment, the Visual Analogue Scale for back pain (VAS-BP), VAS for leg pain (VAS-LP), Oswestry Disability Index (ODI), Patient Satisfaction Rate (PSR), and the complication rate were used.

Results: This study included 57 patients randomly divided into two groups: 30 operated on using the MIS TLIF technique, and 27 operated on using the modified open TLIF technique via the Wiltse approach. 48-month follow-up rates were similar for the two cohorts. Patients did not differ significantly at baseline in terms of ODI, VAS-BP, or VAS-LP. Perioperatively, MIS TLIF was associated with significantly less blood loss (167.3 ± 80.0 vs. 297.9 ± 81.5 ml, p = 1.1E-05), slightly longer procedures (185.7 ± 45.2 vs. 183.1 ± 66.4 minutes, p = 0.76), a lower radiation dose (MIS 16.9 ± 7.1 vs. 22.0 ± 9.7 mGy OPEN p = 0.012), and shorter hospitalisations (MIS 5.9 ± 1.8 vs. 7.7 ± 1.6 days OPEN). The most common complication was radiculitis, which accounted for 33% and 37% in the MIS and the TLIF groups, respectively. The second most common complication was malposition of the fixation material, which accounted for 18.5% in the TLIF group and 20% in the MIS group. The level of fusion achieved was 92.6% in the MIS group versus 92.3% in the TLIF group. There was lower consumption of analgesics in MIS. Patient Satisfaction Rate (PSR) was 90%.

Conclusions: Clinical and radiological outcomes after MIS TLIF in patients with degenerative disease of the lumbosacral region are generally favourable. MIS TLIF was associated with decreased blood loss perioperatively, a lower radiation dose and an earlier discharge, but there was no difference between MIS TLIF and modified open TLIF in 48-month outcomes in terms of disability, back pain, leg pain, quality of life, or patient satisfaction rate or complication rate. Although the differences taper off over time, MIS TLIF has undeniable advantages in the perioperative and early postoperative periods.