Predictive factors for outcomes of anterior-only surgery in multilevel pincer-type cervical spondylotic myelopathy: The role of the posterior compression score.

Abstract

Retrospective observational study. To evaluate the predictive value of the posterior compression score (PCS) for determining the appropriateness of anterior-only surgery in patients with multilevel pincer-type cervical spondylotic myelopathy (CSM). Patients with multilevel pincer-type CSM who underwent anterior decompression and fusion at our institution between January 2018 and December 2023 were retrospectively analyzed. Preoperative PCS was calculated based on MRI findings. Clinical outcomes included Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), and visual analog scale (VAS) for neck and arm pain, with calculation of the JOA recovery rate. Radiological outcomes included postoperative residual compression and improvement in sagittal canal diameter. Logistic regression and receiver operating characteristic (ROC) curve analyses were used to assess the relationship between PCS and postoperative outcomes and to determine the optimal cutoff value. Patients were stratified into low- and high-score groups based on the cutoff value, and 1:1 nearest-neighbor propensity score matching (PSM, caliper = 0.1) was performed to compare clinical and radiological outcomes between groups. A total of 148 patients were included, with a mean follow-up of 12.8 ± 3.3 months. Overall, 93 patients (62.8%) achieved a JOA recovery rate ≥50%, and 144 patients (97.3%) achieved an NDI improvement ≥50%. ROC analysis demonstrated good predictive performance of PCS (AUC = 0.85, 95% CI: 0.78-0.92), with an optimal cutoff value of 2 points for predicting a JOA recovery rate ≥50%. Patients in the low-PCS group (PCS ≤2, n = 91) showed significantly higher JOA recovery (58.2% ± 9.4 vs. 38.8% ± 24.0) and NDI improvement (70.2% ± 5.5 vs. 61.4% ± 20.7) than those in the high-PCS group (P < 0.05). After PSM, baseline characteristics were balanced between groups, with no significant differences in operative time, intraoperative blood loss, postoperative VAS, C2-C7 lordotic angle, or range of motion (ROM) (P > 0.05). However, postoperative JOA scores and recovery rates remained significantly higher, while NDI scores were significantly lower, in the low-PCS group compared with the high-PCS group (P < 0.05). Four cases of reoperation within 24 h occurred, all in the high-PCS group. PCS is a simple and objective indicator for assessing the suitability of anterior-only surgery in patients with multilevel pincer-type CSM. A PCS ≤2 predicts favorable neurological recovery, whereas PCS > 2-particularly > 4-indicates poorer recovery and a higher risk of reoperation, warranting cautious surgical selection.