Feasibility of Posterior Cervical Foraminotomy in Cervical Foraminal Stenosis: Prediction of Surgical Outcomes by the Foraminal Shape on Preoperative Computed Tomography.

STUDY DESIGN: A retrospective cohort study.

OBJECTIVE: The aim of this study was to compare the feasibility of posterior cervical laminoforaminotomy (PCF) for V- or parallel-shaped foraminal stenosis (FS).

SUMMARY OF BACKGROUND DATA: During PCF, the need for extensive facet resection would depend on the extent of any pathology. When resection is extensive, the possibilities of instability and incomplete decompression should be considered.

METHODS: From March 2004 to March 2015, we enrolled 36 patients following single-level PCF procedures for FS. We classified patients by foraminal shape on preoperative computed tomography (CT) scan into V-shaped and parallel-shaped groups. We then compared arm and neck pain using a numeric rating scale (NRS) and clinical outcomes using Odom criteria. Radiological evaluation included dynamic X-rays for instability and CT scans for facet resection.

RESULT: We enrolled 16 and 20 patients in the V-shape and parallel-shape groups, respectively. By Odom criteria, no patient was graded fair or poor in the V group, but five patients were graded as fair and one patient as poor in the parallel group. Continued postoperative arm pain at 1 year, which was related to incomplete decompression, was significantly higher in parallel group. Only one patient complained of postoperative neck pain with an NRS >5, and another five patients sustained radiculopathy with an NRS >5. Among five patients who complained sustained radiculopathy, one patient required revision surgery for incomplete decompression. The amount of facet removal was not different significantly between groups, and no patient had postoperative instability.

CONCLUSION: Although PCF seems to be a good surgical option for V-shaped FS, we experienced worse outcomes for patients with parallel-shaped FS. We recommend that ACDF or more aggressive posterior foraminotomy be performed with fusion when presented with parallel neuroforaminal compression.

LEVEL OF EVIDENCE: 4.