What are the differences in clinical and surgical outcomes between lumbar spine fusion approaches?—a narrative review

Background and Objective: Lumbar interbody fusion (LIF) is a surgical procedure commonly used to treat various spinal pathologies, particularly degenerative disc diseases, spondylolisthesis, and chronic low back pain. This procedure involves removing the damaged disc and inserting a graft or an interbody cage into the intervertebral space to promote fusion between adjacent vertebrae. While originally described as a posterior approach [posterior LIF (PLIF)], this procedure has developed into other approaches, to include anterior (ALIF), transforaminal (TLIF), direct lateral (DLIF or LLIF), and oblique LIFs (OLIF). However, despite its utility and prevalence, there is inconclusive evidence supporting the clinical superiority of one technique over the others with described advantages and disadvantages based on approach. To better delineate their clinical utility, we reviewed the current literature to compare clinical and surgical outcomes between ALIF, OLIF, LLIF, TLIF, and PLIF. Methods: A non-systematic literature search of the PubMed database was conducted. The inclusion criteria were studies published in English and reporting results and outcomes following LIF surgery. The timeframe of the studies was narrowed to between 2005 and 2023. Key Content and Findings: Our review of the literature showed no significant difference in fusion rates, hospital lengths of stay, or patient-reported outcomes between the different approaches. There is evidence that anterior-based approaches (ALIF, LLIF, OLIF) can achieve higher lordosis correction, have lower levels of blood loss, and decreased rates of interbody subsidence compared to posterior-based approaches (PLIF, TLIF), while the posterior-based approaches may have quicker surgical times. In regards to complications, anterior approaches have higher rates of deep vein thrombosis (DVT) and vascular injuries. Rates of postoperative infection were largely similar among the approaches. Conclusions: Anterior-based LIF approaches may achieve superior lordosis correction, exhibit lower blood loss, and experience reduced rates of interbody subsidence compared to posterior-based approaches, while posterior approaches may offer decreased rates of catastrophic vascular or intra-abdominal structure injury, postoperative venous thrombosis, and faster surgical procedure times. Ultimately however, larger, more high-quality prospective studies are needed to further elucidate any differences in surgical and clinical outcomes between these individual techniques.