Lateral versus Anterior Lumbar Interbody Fusion: 2-Year Outcomes from a Prospective Multi-Center Study

Presented at SMISS Annual Forum 2016
By Kee Kim MD
With Peter Passias MD, Ryan DenHaese MD, Clint Hill MD, K. Strenge MD, Alexandre de Moura MD, Chris Ferry MS, Brieta Bejin MS, Kim Martin PhD, Sarah Martineck PA, Tom Glorioso MS, Paul Arnold MD, Ripul Panchal DO,

Disclosures: Kee Kim MD A; Lanx Inc., B; Zimmer Biomet Spine. Peter Passias MD B; Medicrea., Ryan DenHaese MD B; Zimmer Biomet Spine. E; Zimmer Biomet Spine., Clint Hill MD B; Zimmer Biomet Spine., K. Strenge MD B; Zimmer Biomet Spine., Alexandre de Moura MD None, Chris Ferry MS E; Zimmer Biomet Spine., Brieta Bejin MS E; Zimmer Biomet Spine. , Kim Martin PhD E; Zimmer Biomet Spine., Sarah Martineck PA B; Zimmer Biomet Spine., Tom Glorioso MS B; Zimmer Biomet Spine., Paul Arnold MD None, Ripul Panchal DO B; Zimmer Biomet Spine.,

Introduction

Lateral lumbar interbody fusion (LLIF) has become an increasingly popular minimally disruptive technique when treating pain secondary to degeneration and/or instability. However, limited prospective data currently exists comparing the LLIF technique to traditional interbody approaches, particularly anterior lumbar interbody fusion (ALIF). Given that both interbody techniques afford generous disc visualization and the placement of a large stable graft, it is valuable to further understand whether the respective access approaches and/or posterior fixation type may differentiate the outcomes associated with each. 

Aims/Objectives

The aim of this study was to provide prospective long-term evidence comparing circumferential LLIF and ALIF with either interspinous process fixation (ISPF) or pedicle screw fixation (PSF). 

Methods

Data was collected as part of a prospective, controlled, multi-center (11 investigators) study with 24-months follow-up.
A total of 103 subjects were enrolled. All subjects underwent single-level circumferential LLIF (n=57) or ALIF (n=46) for the treatment of degenerative disc disease and/or spondylolisthesis. Interbody technique was selected at the discretion of the surgeon in accordance with their institutional standard-of-care. Subjects were randomized to ISPF or PSF in the posterior aspect. Intraoperative, patient reported, complication/revision, and radiographic outcomes were reported. Statistical comparison was performed using a linear mixed model. 

Results

Specific to the interbody approach, LLIF subjects demonstrated significantly less intraoperative blood loss, operative time, and incisions lengths; however, ALIF subjects required significantly less fluoroscopy. All cohorts demonstrated significant improvement in ODI scores from baseline out to 24mos. At 24mos, the collective ALIF and LLIF cohorts achieved mean ODI score decreases of 22.2 and 27.0pts, respectively. Furthermore, the cohorts achieved ZCQ Physical/Symptom score improvements
of 0.7/1.08pts (ALIF) and 0.83/1.02pts (LLIF), respectively. 24mos interbody fusion success (score of BSF-3): ALIF: 94.7%; LLIF: 88.9%. The only significant difference observed was in ODI improvement at 6weeks, with LLIF+ISPF subjects exceeding all other cohorts (p < 0.05). 

Conclusions

2-year outcomes substantiated all cohorts/techniques as clinically effective interventions when treating single-level degenerative pathology. Outcomes were not notably differentiating between cohorts at longer follow-up. Both LLIF and ISPF exhibited less invasive characteristics when compared to their alternative techniques, translating to greater pain reduction earlier in the post-operative period. In conclusion, the data supports LLIF as a viable alternative to traditional ALIF when anatomically suitable.