Influence of Preoperative Severity on Postoperative Improvement Among Patients With Myeloradiculopathy Following Anterior Cervical Discectomy and Fusion

Study Design: Retrospective cohort. Objective: The aim was to determine how neck pain and disability improve following anterior cervical discectomy and fusion among patients with myeloradiculopathy. Summary of Background Data: Neck pain and disability have traditionally been assessed using the neck disability index (NDI) and visual analog scale (VAS). Few studies have investigated how neck pain/disability improve differently among patients with symptoms of both myelopathy and radiculopathy. Methods: Patients were identified through retrospective review of a prospective surgical database from 2013 to 2020. Patient-reported outcome measures (PROMs) collected included VAS neck and arm, NDI, 12-Item Short Form physical composite score (SF-12 PCS), Patient-Reported Outcomes Measurement Information System physical function (PROMIS PF), and Patient Health Questionnaire 9 (PHQ-9). PROMs were collected preoperatively and up to 1-year postoperatively. Patients were categorized by preoperative symptom severity: high VAS arm (>7); high NDI (>55); high VAS arm and NDI; and moderate symptoms. Linear and logistic regression evaluated the impact of preoperative symptom severity on PROM scores and achievement of minimum clinically important difference (MCID), respectively. Results: A total of 187 patients were included, 98 with neither high VAS arm nor NDI (moderate group), 14 with high NDI, 46 with high VAS arm, and 29 with high NDI and VAS arm. Postoperatively, greater symptom severity was a significant predictor of VAS neck (all timepoints; P <= 0.002, all), VAS arm (6 weeks; P=0.007), NDI (6 weeks to 6 months; P<0.001, all), SF-12 PCS (6 months; P=0.004), PROMIS PF (6 weeks; P=0.007), and PHQ-9 (6 weeks to 6 months; P<0.001, all). Mean postoperative improvement was different among the four severity groups for VAS arm, NDI, and VAS neck (except for 1-year) (P <= 0.002, all). Overall MCID achievement rates were significantly greater among higher symptom severity groups across VAS arm and NDI (P <= 0.003, both). Conclusion: PROM improvement and MCID achievement for NDI, VAS neck, and VAS arm differed based on symptom severity.