Minimally Invasive versus Open Transforaminal Lumbar Interbody Fusion in Obese Patients

Study Design: Retrospective review of prospectively collected data. Objectives This study aimed to compare the clinical outcomes of obese patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) and open TLIF. Summary of Background Data: The perioperative benefits of minimally invasive surgery in obese patients have been described. However, there is limited literature on the patient-reported outcomes (PROs), satisfaction and return to work following MIS-TLIF and open TLIF in this subgroup of patients. Methods: Obese patients (BMI ≥30.0 kg/m 2 ) who underwent a primary, one- to two-level open and MIS-TLIF were stratified and matched using propensity scoring. Operative time, length of stay and perioperative outcomes were recorded. Patient-reported outcomes (PROs) including Oswestry Disability Index, Short Form-36 Physical Component Score, Mental Component Score, Visual Analogue Scale for back pain and leg pain were compared at each postoperative time point. Achievement of minimal clinically important difference (MCID), patient satisfaction and return to work were also assessed. Revision procedures were recorded at mean 10±3.3 years follow-up. Results: In total, 236 obese patients were included: 118 open TLIF and 118 MIS-TLIF. Length of stay was longer in the Open TLIF cohort and there was a trend towards a higher complication rate. However, there was no difference in operative time, transfusions or readmissions. Patients who underwent open TLIF reported worse ODI ( P =0.043) and VAS leg pain at 2 years, although the latter did not reach statistical significance ( P =0.095). Achievement of MCID for each PRO, patient satisfaction and return to work were also comparable. Conclusions: Obese patients who underwent MIS-TLIF had a shorter length of stay and improved functional disability at 2 years compared those who underwent open TLIF. However, a similar proportion achieved a clinical meaningful improvement. Patient satisfaction and return to work were also comparable at 2 years. Level of Evidence: Level III, retrospective cohort study.