Quantitative evaluation of cervical muscles in patients with degenerative cervical myelopathy using diffusion tensor imaging metrics

Aims The objective of this research was to assess the diffusion tensor imaging (DTI) parameters of deep cervical muscles in patients diagnosed with degenerative cervical myelopathy (DCM) before and after surgery at different follow-up stages, and to analyze their relationship with functional scores. Methods This study involved 30 patients with DCM who underwent cervical laminoplasty. DTI imaging and clinical assessments were performed preoperatively as well as at three-month and six-month follow-up. DTI parameters (fractional anisotropy (FA); mean diffusivity (MD); radial diffusivity (RD); and axial diffusivity (AD)) of cervical paraspinal muscles (multifidus and semispinalis cervicis) were measured, and mean values were calculated. Preoperative and postoperative changes in DTI parameters were analyzed using the Friedman test. Spearman correlation and linear regression analyses was conducted to assess the relationship between preoperative cervical paraspinal muscle DTI measurements and changes in modified Japanese Orthopedic Association (mJOA) scores and visual analogue scale (VAS) at preoperative and three-month and six-month follow-up. Multivariate logistic regression analysis was performed to assess the relationship between recovery rates of mJOA and VAS and changes of DTI metrics. Results Preoperative paraspinal muscle FA is associated with preoperative mJOA scores ( r = 0.372, p = 0.043). Preoperative paraspinal muscle FA significantly correlated with VAS change at three-month ( r = −0.461, p = 0.010) and six-month follow-up ( r = −0.477, p = 0.008), and also correlated with mJOA recovery rate at six-month follow-up ( r = 0.368, p = 0.045). Higher preoperative paraspinal muscle FA was a significant predictor of decreased VAS scores at three-month and six-month follow-up ( β = −0.411, p = 0.024; β = −0.385, p = 0.035) and increased mJOA scores at six-month follow-up ( β = 0.401, p = 0.028). Changes in FA (p = 0.033, OR 1.05 (95% CI 1.01 to 1.11)) and RD (p = 0.028, OR 1.27 (95% CI (1.03 to 1.58)) at six months’ follow-up may be variables influencing the VAS change. Conclusion In DCM patients, changes in DTI parameters from preoperative to postoperative follow-up stages can indicate paraspinal muscle recovery after cervical surgery. DTI examination before surgery can predict patient recovery outcomes. Cite this article: Bone Joint Res 2026;15(2):179–189.