ObjectiveTo compare the effectiveness of endoscopic anterior cervical discectomy and fusion (Endo-ACDF) and microscope-assisted ACDF (Micro-ACDF) in the treatment of single-level cervical spondylotic myelopathy (CSM). MethodsA retrospective analysis was conducted on the clinical data of 44 patients with single-level CSM who underwent ACDF between February 2022 and January 2024 and met the selection criteria. These patients were divided into Endo-ACDF group (22 cases) and Micro-ACDF group (22 cases). There was no significant difference (P>0.05) between the two groups in baseline data, including gender, age, body mass index, disease duration, surgical level, and preoperative Japanese Orthopaedic Association (JOA) score, Cobb angle, and the degree of prevertebral soft tissue swelling (PSTS) at C2-6. The operation time, postoperative hospital stay, intraoperative blood loss, postoperative drainage volume, total blood loss, and hidden blood loss were recorded and compared between the two groups. The Cobb angle and PSTS degree at C2-6 were measured based on X-ray films at 2-3 days after operation. The JOA score was used to assess spinal cord function at 1 year after operation. The differences between pre- and post-operation (change values) in these indicators were calculated and compared between groups. Results All operations in both groups were successfully completed. Compared to the Micro-ACDF group, the Endo-ACDF group had significantly longer operation time and significantly lower total blood loss and hidden blood loss (P<0.05). No significant difference was found between the two groups in intraoperative blood loss, postoperative hospital stay, or postoperative drainage volume (P>0.05). No operation-related complication occurred during or after the procedures. All patients were followed up 12-16 months (mean, 13.9 months). At 1 year after operation, the JOA scores and Cobb angles in both groups showed significant improvement compared to preoperative values (P<0.05). However, the change values for JOA scores and Cobb angles showed no significant difference between the groups (P>0.05). The postoperative PSTS degree at C2-6 was significantly different from preoperative values in both groups (P<0.05), but the change value did not differ significantly between the two groups (P>0.05). The imaging re-examination showed the satisfactory positioning of the cages and internal fixation.ConclusionBoth Endo-ACDF and Micro-ACDF provide satisfactory effectiveness in treating single-level CSM, with no significant difference in the PSTS degree. Furthermore, Endo-ACDF is associated with less hidden blood loss.