INTRODUCTION: XLIF has been shown to result in good short‐term outcomes with minimal morbidity. Long‐term outcomes have been assumed to mimic those of other interbody fusion procedures. However, no reports to date have focused specifically on fusion rates associated with XLIF.
METHODS: From our prospective, nonrandomized single‐site consecutive series of 710 XLIF patients, patients reaching 1 year follow‐up were asked to undergo a voluntary lumbar spine CT scan. CT scans from 66 patients with 1 year follow‐up have been obtained to date, which were reviewed to evaluate fusion, and compared with clinical results and patient satisfaction.
RESULTS: Patient age ranged from 34‐87yrs (average 61.8yrs). 88 levels were treated: 50 1‐levels, 10 2‐levels, and 6 3‐levels; 16 at L2‐3, 32 at L3‐4, and 37 at L4‐5. Grafting materials included a composite of DBM, local bone graft, and bone marrow aspirate. Twelve surgeries included supplemental unilateral pedicle screw fixation performed in the same surgical position. Average disk height improved from 6.1mm to 9.4mm at one‐year follow‐up and 100% at 24 months. Signs of fusion by Lenke scores of 1 or 2 were 97% at 6 months and 99% at 12 months. Fusion by CT criteria of >50% area fused was achieved in all but 3 levels (96.8%). Average VAS pain scores decreased from 8.6 at pre‐op to 1.7 at 12months with a slight increase to 2.1 at 24 months. At 1yr, 89% of patients were satisfied or very satisfied with their outcomes. The surgeon‐reported clinical assessment was good or excellent in 84%.
CONCLUSION: XLIF has proven to be a safe and effective procedure. This is the first report specifically highlighting fusion rates of XLIF by CT assessment. High rates of fusion can be reasonably expected using this minimally invasive interbody fusion procedure.