Obesity Does Not Adversely Affect Longterm Outcomes of Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Matched Cohort Analysis

Minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) is an established technique for the treatment of degenerative spine disease. The larger body habitus of obese patients increases the intraoperative complexity of MI-TLIF. Therefore, it is unclear whether this procedure is appropriate for this population. The goal of this study was to compare postoperative outcomes for obese patients vs nonobese patients undergoing MI-TLIF through a matched cohort analysis. A retrospective review was performed to identify patients who underwent MI-TLIF at a single institution with a minimum follow-up of 5 years. Patients were divided into 2 cohorts: nonobese (body mass index <30 kg/m(2)) and obese (body mass index >= 30 kg/m(2)). Each cohort was matched for age, sex, and levels operated. Perioperative data and patient-reported outcomes were compared. Radiographic outcomes were measured at final follow-up. Standard binomial and categorical comparative analyses were performed. A total of 148 patients were included. Of obese patients, 17.6% required revision surgery compared with 16.2% of nonobese patients (P=.826). Both cohorts had a similar proportion of pelvic incidence-lumbar lordosis mismatch correction (P=.780). Mean change in functional outcome scores for each cohort did not differ significantly. Obese patients had clinically minor but statistically significantly greater blood loss and longer operative times than nonobese patients (P<.001). Obese and nonobese patients undergoing MI-TLIF showed no long-term differences in revision rate, radiologic outcome, or functional outcome after long-term follow-up. Obese patients had slightly greater blood loss and longer operative times. Our findings suggest that MI-TLIF is an appropriate alternative to traditional open lumbar fusion for obese patients.