Reevaluating the 50% facetectomy threshold in posterior cervical foraminotomy: a comparative clinical and...

Posterior cervical foraminotomy (PCF) is a motion-preserving procedure for cervical radiculopathy. Traditional guidelines recommend limiting facet resection to less than 50% to preserve spinal stability, a threshold derived from cadaveric biomechanical studies. However, the clinical relevance of this limit has not been fully validated.

To evaluate whether facet joint resection exceeding 50% during PCF adversely affects clinical outcomes or radiographic stability.

Retrospective cohort study conducted at a single tertiary referral center.

A total of 85 patients (204 operated levels) who underwent PCF between 2005 and 2023 were included. Patients were categorized into ≥50% resection (Group O, n=58) and <50% resection (Group C, n=27).

Clinical outcomes were assessed using self-report instruments, including the Visual Analog Scale (VAS) for neck and arm pain, the Neck Disability Index (NDI), and the Japanese Orthopaedic Association (JOA) score. Physiologic parameters were evaluated on radiographs and included C2-C7 Cobb angle, sagittal vertical axis, segmental range of motion (ROM), gliding distance, interspinous distance, disc height, bone bridge formation, and the presence of foraminal restenosis. Functional outcomes were not applicable in this cohort.

Clinical and radiographic data were assessed preoperatively and at 6 months and 2 years postoperatively. Segment-level analyses were performed using linear mixed-effects models to account for clustering within patients and to evaluate the association between the extent of resection and radiographic changes.

Both groups demonstrated significant postoperative improvement in VAS and NDI scores without inter-group differences at any time point. Spinal alignment and global motion parameters remained comparable during follow-up. Bone bridge formation was more frequent in the ≥50% resection group (66.7% vs 26.3%, p=.002). At the segmental level, greater resection was significantly associated with modest reductions in gliding (B = -0.016, p=.004) and interspinous distance (B = -0.108, p<.001) at 2 years, without evidence of instability.

Facet resection exceeding 50% during PCF did not compromise clinical outcomes or radiographic stability at 2 years, suggesting similar short-term performance to limited resection. Minor radiographic changes such as accelerated bone bridge formation, were observed, warranting further prospective evaluation of long-term stability. These preliminary findings suggest that surgeons may prioritize complete neural decompression over strict adherence to the 50% threshold when anatomically necessary.