Neurosurg Focus. 2026 Jul 1;61(1):E12. doi: 10.3171/2026.3.FOCUS2624.
ABSTRACT
OBJECTIVE: The optimal surgical treatment for lumbar spinal stenosis (LSS) with degenerative spondylolisthesis (DS) remains controversial. Posterior lumbar facet arthroplasty preserves motion after decompression and may address some of the limitations of fusion techniques. The Total Posterior Spine System (TOPS) investigational device exemption trial compared decompression with facet arthroplasty to decompression plus fusion (open with interbody). This study reports the 3-year outcomes from this trial.
METHODS: This randomized, controlled, multicenter trial enrolled 321 patients with LSS and grade I DS across 37 sites (2:1 randomization of arthroplasty to fusion). Eligible patients were 35-80 years old, had failed ≥ 6 months of nonsurgical treatment, and met thresholds for disability and leg pain. The primary endpoint was a composite clinical success score at 36 months, defined by four criteria: 1) no reoperation or lumbar injection, 2) no major device adverse events, 3) ≥ 15-point improvement in the Oswestry Disability Index (ODI), and 4) no new/progressive neurological deficit. Secondary outcomes included the ODI score, visual analog scale (VAS) scores for back and leg pain, the Zurich Claudication Questionnaire (ZCQ), device-related adverse events, and reoperations.
RESULTS: One hundred seventy-nine patients in the arthroplasty (TOPS) group and 74 in the fusion group were eligible for the 36-month analysis. The composite clinical success achievement rate was significantly higher in the arthroplasty group (76.0%) than in the fusion group (56.8%; p = 0.0038). The rate of reoperation or lumbar injection was significantly lower for the arthroplasty group (14.0%) compared to the fusion group (25.3%; p = 0.0222). Arthroplasty was associated with a significantly higher minimal clinically important difference (MCID) achievement rate for VAS back pain score compared with fusion (85.2% vs 72.2%; p = 0.041). Although there was no significant difference in ODI score, VAS leg pain score, or ZCQ component scores between groups, the arthroplasty group trended toward higher MCID achievement rates across all patient-reported outcome measures. There was no significant difference in reoperation failure rates between groups (5.8% for arthroplasty vs 9.5% for fusion; p = 0.329).
CONCLUSIONS: Decompression and dynamic stabilization with lumbar facet arthroplasty was associated with statistically significantly superior clinical outcomes and lower rates of secondary invasive procedures, including reoperations and injections, compared with decompression and fusion. Long-term follow-up is critical in defining the role of lumbar facet arthroplasty for the treatment of DS.
PMID:42385242 | DOI:10.3171/2026.3.FOCUS2624
