In Vitro Biomechanical Experiment on the Effect of Unilateral Partial Facetectomy Performed by Percutaneous Endoscopy on the Stability of Lumbar Spine.

Objectives: This study's purpose is to investigate the lumbar biomechanical effects of unilateral partial facetectomy (UPF) of different facet joint (FJ) portions under percutaneous endoscopy.

Methods: Forty fresh calf spine models were used to simulate UPF under a physiological load performed through three commonly used needle insertion points (IPs): (1) The apex of the superior FJ (as the first IP); (2) The midpoint of the ventral side of the superior FJ (as the second IP); (3) The lowest point of the ventral side of the superior FJ (as the third IP). The range of motion (ROM) and the L4/5 intradiscal maximum pressure (IMP) were measured and analyzed under a physiological load in all models during flexion, extension, left-right lateral flexion, and left-right axial rotation.

Results: When UPF was performed through the second IP, the ROM of the lumbar spine and the L4/5 IMP in the calf spine models were not statistically different from the intact calf spine model.

Conclusions: UPF through the second IP resulted in a minimal impact on the biomechanics of the lumbar spine. Thus, it might be considered the most appropriate IP for UPF.