Background: Lateral lumbar interbody fusion (LLIF) is not associated with many of the complications seen in other interbody fusion techniques. This study used computed tomography (CT) scans, the radiographic gold standard, to assess interbody fusion rates achieved utilizing the LLIF technique in high-risk patients.
Methods: We performed a retrospective review of patients who underwent LLIF between January 2008 and July 2013. Forty-nine patients underwent nonstaged or staged LLIF on 119 levels with posterior correction and augmentation. Per protocol, patients received CT scans at their 1-year follow-up. Of the 49 patients, 21 patients with LLIF intervention on 54 levels met inclusion criteria. Two board-certified musculoskeletal radiologists and the senior surgeon (JZ) assessed fusion.
Results: Of the 21 patients, 6 patients had had previous lumbar surgery, and the cohort's comorbidities included osteoporosis, diabetes, obesity, and smoking, among others. Postoperative complications occurred in 12 (57.1%) patients and included anterior thigh pain and weakness in 6 patients, all of which resolved by 6 months. Two cases of proximal junctional kyphosis occurred, along with 1 case of hardware pullout. Two cases of abdominal atonia occurred. By CT scan assessment, each radiologist found fusion was achieved in 53 of 54 levels (98%). The radiologists' findings were in agreement with the senior surgeon.
Conclusion: Several studies have evaluated LLIF fusion and reported fusion rates between 88%-96%. Our results demonstrate high fusion rates using this technique, despite multiple comorbidities in the patient population. Spanning the ring apophysis with large LLIF cages along with supplemental posterior pedicle screw augmentation can enhance stability of the fusion segment and increase fusion rates.
Keywords: Comorbidity; lumbar vertebrae; spinal fusion; surgical procedures–minimally invasive; tomography–x-ray computed.