Symptom duration and postoperative outcomes in degenerative cervical myelopathy: a systematic review and meta-analysis.

BACKGROUND

Surgical decompression is regarded as standard treatment for degenerative cervical myelopathy (DCM). However, the timing of surgery remains a critical yet unresolved issue in clinical practice. Therefore, this meta-analysis aimed to evaluate the impact of symptom duration on surgical outcomes and determine the optimal timing for surgery.

METHODS

A systematic search was conducted on 16th November 2025 using PubMed, Ovid, Scopus, and Web of Science databases to identify eligible articles. Studies comprising patients with DCM undergoing surgery, assessing outcome by mJOA score at a minimum of 12 months of follow-up, were included. A risk of bias in the included studies was assessed using the Quality in Prognostic Studies (QUIPS) tool.

RESULTS

From 1522 records, 14 studies encompassing a total of 3162 patients were included in the current meta-analysis. Symptom duration was significantly associated with postoperative mJOA score according to univariate (OR: 2.15; 95% CI: 1.64-2.81) and multivariate data (OR: 1.78; 95% CI: 1.23-2.57). Meta-regression showed that neither baseline mJOA score nor age affected the association. Moreover, early surgery resulted in reduced neck pain and disability measured by the NDI score (OR: 1.56; 95% CI: 1.24-1.95), but not quality of life according to EQ-5D (OR: 1.47; 95% CI: 0.74-2.89). At the 6-month and 12-month cut-off points, patients with longer symptom duration had significantly worse outcomes in terms of mJOA score, and after exclusion of high-risk-of-bias studies, only at the 12-month cut-off point. However, the test for subgroup differences was insignificant (p = 0.89).

CONCLUSION

Longer symptom duration is associated with poor surgical outcomes. Therefore, the duration of symptoms should be regarded as a clinically meaningful factor when counseling patients with DCM and planning surgical intervention. An optimal threshold for symptom duration, indicating when the surgery should be performed to prevent poor outcomes, cannot be recommended due to limitations of published data and needs to be established by further well-designed prospective studies. Future research should also aim to define optimal time cut-offs across different degrees of DCM severity and varied disease trajectories.