ABSTRACT
Background: Minimally invasive lumbar interbody fusion (MI-LIF) procedures are an effective treatment for patients with degenerative lumbar disease (DLD). However, consensus does not exist among surgeons for selecting 1 approach over another. The objectives were to collect patientreported, surgical and fusion outcome data at 1 year after surgery for patients receiving either anterior lumbar interbody fusion (ALIF), direct lateral interbody fusion (DLIF), oblique lumbar interbody fusion (OLIF), posterior lumbar interbody fusion (PLIF), transforaminal lumbar interbody fusion (TLIF) or midline lumbar interbody fusion (MIDLF) for DLD. Methods: A total of 340 patients with DLD were consecutively enrolled in a prospective, global, multicentre cohort study (MASTERS-D2;NCT02617563). Patients were treated according to the surgeon's choice with 1 of 6 MI-LIF procedures. Outcome data for disability (Oswestry Disability Index), back and leg pain (Visual Analogue Scale), quality of life (EQ-5D) were collected at baseline, 4 weeks, 3 months and 12 months. Demographic, surgical and safety data were also recorded. Fusion status was assessed by using computed tomography or x-rays at 1 year (plus or minus 6 mo) after surgery. Paired sample t tests were used to test for improvement from baseline. Results: One year after surgery, patients attained clinically significant improvements on all patient-reported outcome measures regardless of approach used. Patients who were selected to receive an ALIF comprised the highest proportion of smokers, were the youngest and had the longest operating time, but low fluoroscopy exposure. Anterolateral (ALIF, DLIF, OLIF) compared with posterior (MIDLF, PLIF, TLIF) approaches had the least amount of blood loss, despite similar or longer surgical times. Within 1 year of follow-up, 7 device-related and 7 surgery-related serious adverse events (SAEs) had been recorded. Assessment of fusion was hindered by the effects of COVID-19. In total, 196 out of 340 (57.6%) patients were assessed. The aggregate fusion rate for anterolateral approaches was 88.1% and for posterior approaches 85.1% at 12 months of follow-up. Conclusion: All 6 approaches for MI-LIF surgery demonstrate favourable patient-reported and surgical outcomes for patients with DLD. Continuing data collection up to 5 years after surgery will yield information on long-term effectiveness, safety, health economics and revision surgery and on the long-term impact of surgeons' choice of approach.