Radiological differences between patients with degenerative cervical myelopathy according to different levels of maximum compression

Degenerative cervical myelopathy(DCM) is a common disease that causes spinal cord dysfunction. Cervical sagittal alignment and motion parameters, as well as cervical musculature, play important roles in disease evaluation and treatment. Previous studies have mainly focused on radiological differences between patients with DCM and healthy individuals. The aim of this study was to analyze differences in radiological characteristics between patients with high-level and low-level DCM in order to provide preliminary evidence for early recognition and understanding of the underlying pathological changes. This retrospective study included 76 patients with DCM who underwent surgical treatment. Patients were divided into a high-level group (26 cases, C3-4 and C4-5) and a low-level group (50 cases, C5-6 and C6-7) according to the level of maximum compression. Cervical sagittal parameters, muscle cross-sectional area, and fatty infiltration ratio were measured and compared between the two groups. After FDR correction, RomCobb5-7 remained significantly lower in the high-level group. No significant between-group differences were found in muscle cross-sectional area. However, fatty infiltration showed clear segment-specific differences: upper cervical muscle FI ratios were higher in the high-level group, whereas lower cervical muscle FI ratios were higher in the low-level group. In multivariable analyses, MCC was positively associated with several FI ratios, whereas RomCobb2–5 and RomCobb5–7 were not significantly associated with muscle FI ratios. Segment-specific differences in cervical sagittal parameters and muscle fatty infiltration were observed between high-level and low-level DCM. The underlying mechanism may be partly related to segment-specific neural involvement. These findings may improve understanding of the radiological and muscular characteristics of DCM at different compression levels.