The Influence of Body Mass Index on Functional Outcomes, Satisfaction, and Return to Work After Single-level Minimally-invasive Transforaminal Lumbar Interbody Fusion: A Five-year Follow-up Study.

Study Design: Retrospective study using prospectively collected registry data.

Objectives: To evaluate the effect of obesity on patient-reported outcome measures of pain, disability, quality of life, satisfaction, and return to work after single-level minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

Summary Of Background Data: MIS-TLIF is an appealing alternative for obese patients with potentially lower complication risk. However, there is limited data investigating the influence of obesity on outcomes 5 years after MIS-TLIF.

Methods: Prospectively collected registry data of 296 patients who underwent single-level MIS-TLIF at a single institution were reviewed. Patients had complete 2- and 5-year follow-up data. Patients were stratified into control (<25.0 kg/m), overweight (25.0-29.9 kg/m), and obese (≥30.0 kg/m) groups. Outcomes assessed were visual analogue scale for back pain, leg pain, Oswestry Disability Index, Short-form 36, North American Spine Society score for neurogenic symptoms, return to work (RTW), return to function (RTF), satisfaction, and expectation fulfilment. Length of operation, length of stay, and comorbidities were recorded.

Results: Among the patients, 156 (52.7%) had normal weight, 108 (36.5%) were overweight, and 32 (10.8%) were obese. There was no difference in length of operation or hospitalization (P > 0.05). All three groups had comparable preoperative scores at baseline (P > 0.05). At 5 years, the control group had significantly higher PCS compared with the overweight (P = 0.043) and obese groups (P = 0.007), although the change in scores was similar (P > 0.05). The rate of MCID attainment, RTW, RTF, expectation fulfilment, and satisfaction was comparable.

Conclusion: Nonobese patients had better physical well-being in the mid-term, although obese patients experienced a comparable improvement in clinical scores. Obesity had no impact on patients' ability to RTW or RTF. Equivalent proportions of patients were satisfied and had their expectations fulfilled up to 5 years after MIS-TLIF.

Level Of Evidence: 3.