What Preoperative Factors Are Associated With Achieving a Clinically Meaningful Improvement and Satisfaction After Single-Level Transforaminal Lumbar Interbody Fusion for Degenerative Spondylolisthesis?

Study design Prospective cohort study. Objectives The purpose of this study was to identify preoperative factors associated with clinically meaningful improvement, patient satisfaction and expectation fulfilment at 2 years follow-up in patients undergoing single-level TLIF for degenerative spondylolisthesis. Methods Patients who underwent a primary, single-level TLIF for degenerative spondylolisthesis between 2006 and 2015 were identified from a prospectively maintained institutional spine registry. Baseline characteristics and PROMs including the Oswestry Disability Index (ODI), 36-Item Short-Form Physical Component Score (SF-36 PCS), Mental Component Score (SF-36 MCS), Visual Analogue Scale (VAS) back pain, and VAS leg pain were collected preoperatively, at 1 month, 3 months, 6 months, and 2 years. Results A total of 997 patients were included. Multivariate analyses showed that increasing age (OR 1.039, P < .001) and better preoperative ODI (OR .984, P = .018) were associated with achieving minimal clinically important difference (MCID) for VAS Back. Increasing age (OR 1.032, P = .007) and better preoperative VAS Back (OR .783, P < .001) were associated with achieving MCID for VAS Leg. Lower BMI (OR .952, P = .024) and better preoperative ODI (OR .976, P < .001) were associated with achieving MCID for SF-36 PCS. Importantly, a better preoperative SF-36 MCS was associated with MCID attainment for ODI (OR 1.038, P < .001), satisfaction (OR 1.034, P < .001) and expectation fulfilment (OR 1.024, P < .001). Conclusion Patients who were older, have less preoperative disability and better preoperative mental health were significantly more likely to attain clinically meaningful improvement in PROMs and postoperative satisfaction after single-level TLIF. Identification of these factors would aid surgeons in patient selection and surgical counselling for single-level TLIF.