Association of Degenerative Cervical Spondylolisthesis with Clinical Presentation and Surgical Outcomes in Degenerative Cervical Myelopathy: A Single-Centre Retrospective Cohort Study

Abstract Purpose: The clinical significance of degenerative cervical spondylolisthesis (DCS) in patients undergoing surgery for degenerative cervical myelopathy (DCM) remains unclear. We examined its association with clinical presentation, operative strategy, and postoperative outcomes. Methods: We retrospectively analysed prospectively collected data from 102 surgically treated patients with DCM (2013–2024), stratified by the presence of DCS on preoperative MRI. Neurological and patient-reported outcomes were evaluated before surgery, at 3–4 months, and at 1 year. Between-group comparisons were exploratory and unadjusted. Results: DCS was identified in 18 patients (17.6%). Patients with DCS were older (median 61.0 vs 56.5 years; p = 0.014) and had lower preoperative mJOA scores (13.0 vs 14.0; p = 0.006). Anterior surgery was less frequent (55.6% vs 85.7%; p = 0.007), whereas posterior surgery was more frequent (38.9% vs 13.1%; p = 0.016). Constructs included more levels (median 3 vs 2; p = 0.001). At 1 year, median mJOA remained lower in patients with DCS (14.5 vs 16.0; p = 0.040), but neither change in mJOA from baseline nor Hirabayashi recovery rate differed significantly between groups (p = 0.752 and p = 0.328, respectively). Conclusion: DCS was associated with worse baseline neurological function and more extensive surgical treatment. Although absolute postoperative mJOA was lower, neurological improvement was observed in both groups. Larger adjusted studies are needed to establish whether DCS independently influences surgical outcomes.