Risk factors for residual neuropathic pain using specific screening tools in postoperative patients with ossification of the posterior longitudinal ligament of the cervical spine.

Purpose: Ageing, long illness duration, and poor preoperative Japanese Orthopaedic Association (JOA) score were reported to be risk factors for residual pain after cervical ossification of the posterior longitudinal ligament (cOPLL). In this study, we focused on residual neuropathic pain (NeP) and aimed to elucidate risk factors for residual NeP after cOPLL.

Methods: Total of 234 patients who underwent cOPLL surgery were included. NeP was evaluated using painDETECT (PDQ) and Spine painDETECT (SPDQ) questionnaires. Score of ≥ 13 / ≥ 0 was defined as NeP for PDQ/SPDQ. Patient backgrounds factors, preoperative radiographic factors and surgical factors were reviewed, and comparisons between the NeP(+) and NeP(-) groups were made. Independent risk factors for residual NeP were evaluated using multiple logistic regression analysis.

Results: Prevalence of residual NeP after cOPLL was 22.6% on PDQ and 55.1% on SPDQ. Preoperative JOA score was significantly lower in the NeP(+) group for PDQ compared with that in the NeP(-) group. Additionally, cervical lordosis angle was significantly lower in the NeP(+) group for SPDQ compared with that in the NeP(-) group. Following multiple logistic regression analysis, poor preoperative JOA score was identified as a risk factor for NeP on the PDQ. Poor preoperative JOA score and low cervical lordosis angle were identified as risk factors using the SPDQ.

Conclusions: We found high prevalence of residual NeP after cOPLL. Patients with a poor preoperative JOA score and low cervical lordosis angle might be at risk for residual NeP after surgery evaluated by PDQ or SPDQ and should be monitored with greater care after surgery.