Facet Arthrodesis with the FFX Device: One-Year Results from a Prospective Multicenter Study

Background: Facet osteosynthesis can be performed to treat facet syndrome (FS) and reduce spinal instability following laminectomy in patients with lumbar spinal stenosis (LSS). The present study evaluated clinical and radiological outcomes following facet osteosynthesis with the FFX device. Methods: Patients with FS or LSS were prospectively enrolled in a single-arm, multicenter study. The device was placed at affected levels with or without concomitant posterior lumbar interbody fusion (PLIF) procedures. The visual analog scale (VAS) for back and leg pain and Oswestry Disability Index (ODI) were evaluated preoperatively and postoperatively. Computed tomography scans to assess fusion and migration were performed 1 year following surgery. Results: Fifty-three patients (26 men/27 women) with a mean age of 65.0 +/- 9.6 years (range: 37-83 years) were enrolled. A total of 205 FFX devices were implanted with 15 patients undergoing concurrent PLIF procedures. There were no intraoperative or postoperative surgical complication reported, and no patient required revision surgery. Mean VAS leg and back pain scores significantly improved from 5.57 to 2.09 (P < .001) and 5.74 to 3.13 (P < .001), respectively, between the preoperative and 1 year follow-up assessments. Mean ODI scores also significantly improved from 44.7% to 24.0% (P < .001) during the same time period. Facet fusion occurred with 86.3% of device placements after 12 months. There was 1 (0.5%) asymptomatic device migration. Eight devices (3.9%) were considered misplaced. Conclusions: The use of the FFX device is associated with a significant reduction in both pain and disability following surgery with a high facet joint fusion rate.