Unilateral Versus Bilateral Cages in Lumbar Interbody Fusions: A Meta-Analysis of Clinical and Radiographic Outcomes

World Neurosurg. 2024 Jun:186:158-164. doi: 10.1016/j.wneu.2024.03.142. Epub 2024 Mar 30.

Abstract

Background: Bilateral cages are often used for interbody fusion. However, this procedure may not be possible in some cases making unilateral cages a reasonable alternative. The literature remains divided on the clinical and radiological distinctions when comparing unilateral to bilateral cages in lumbar interbody fusion. Thus, this meta-analysis will analyze the clinical and radiographic outcomes between these 2 groups.

Methods: PubMed, Cochrane, and Google Scholar (page 1-20) were searched till January 2024. The clinical outcomes evaluated were the incidence of adverse events, surgery-related parameters, and patient reported outcomes.

Results: Lower rates of pseudoarthrosis, subsidence, were reported in the bilateral cages group (P = 0.01, P = 0.001, respectively) whereas shorter operative time (OR time), and lower estimated blood loss were seen in unilateral cage group (P < 0.001, and P = 0.003). There was no statistically significant difference in the remaining analyzed outcomes.

Conclusions: Unilateral cages were shown to be superior due to their reduced OR time and estimated blood loss. As for the higher rate of pseudoarthrosis, this outcome may not be related to the cage numbers and it did not affect clinical outcomes. Nevertheless, one must consider other factors such as radiographic sagittal parameters before making a surgical decision.

Keywords: Bilateral; Cage; Interbody fusion; Pseudoarthrosis; Unilateral.

Publication types

  • Meta-Analysis
  • Comparative Study
  • Review

MeSH terms

  • Blood Loss, Surgical / statistics & numerical data
  • Humans
  • Lumbar Vertebrae* / diagnostic imaging
  • Lumbar Vertebrae* / surgery
  • Operative Time
  • Postoperative Complications / epidemiology
  • Postoperative Complications / etiology
  • Pseudarthrosis
  • Spinal Fusion* / methods
  • Treatment Outcome