Comparison of the Clinical Outcome in Overweight or Obese Patients After Minimally Invasive Versus Open Transforaminal Lumbar Interbody Fusion

STUDY DESIGN: This is a prospective single-center nonrandomized control clinical study involving 81 overweight or obese patients who underwent minimally invasive or open transforaminal lumbar interbody fusion (TLIF). OBJECTIVE: The objective of this study was to evaluate the safety and efficacy of minimally invasive TLIF as an alternative technique in overweight or obese patients. SUMMARY OF BACKGROUND DATA: Spinal surgery in obese patients is associated with increased complications, blood loss, and operative times. The potential benefits of minimally invasive lumbar surgery in obese patients have been discussed in a few studies. However, there have been no prospective clinical reports published on the comparison of minimally invasive or open TLIF (OTLIF) in obese patients. METHODS: Eighty-one patients, 25 male and 56 female, with an average age of 55.3 years (43-81 y) were prospectively evaluated. The main inclusion criterion was a body mass index ≥25. The mean body mass index was 28.9±3.2. All patients suffering from lumbar canal stenosis (n=43), spondylolisthesis (n=29), or postlaminectomy instability (n=9) underwent 1-level minimally invasive TLIF (MiTLIF, n=43) or OTLIF (n=39). The following data were compared between 2 groups: operative time, blood loss, x-ray exposure time, clinical and radiographic outcomes, and perioperative complications. The clinical outcome was assessed using the visual analogue scale and the Oswestry Disability Index (ODI). Radiographic evaluation of the lumbar spine was performed at 12 months postoperatively. RESULTS: In comparison with the OTLIF group, the MiTLIF group had significantly less operating time, less blood loss, and less postoperative back pain. The radiation time was significantly longer in the MiTLIF group. The clinical outcomes (Oswestry Disability Index scores) were basically identical in the 2 groups. Radiographic evaluation showed satisfactory bony union at the fixed level in both the MiTLIF group (42/43 cases) and the OTLIF group (38/39 cases). Overall complication rates were slightly higher in the OTLIF group, with 17.9% of overweight or obese patients having perioperative complications. CONCLUSIONS: MiTLIF is a safe and reliable procedure for treatment of overweight or obese patients. The minimally invasive technique offers several potential advantages when compared with the open procedure. Although this technique needs a longer x-ray exposure time, it may still be a good option for overweight or obese patients.