Cervical Paraspinal Muscle Atrophy Is Associated With Internal Carotid Artery Stenosis.

STUDY DESIGN: Retrospective cross-sectional study. OBJECTIVE: The objective of our study is to assess the relationship between carotid artery stenosis (CAS) and muscle morphology. SUMMARY OF BACKGROUND DATA: Paraspinal muscle degeneration, marked by fatty infiltration (FI) and reduced functional cross-sectional area (fCSA), contributes to spine instability, chronic pain, and disc degeneration. While abdominal aortic calcification is linked to lumbar muscle atrophy, cervical vascular-muscle associations remain underexplored. METHODS: Sixty-five patients undergoing primary cervical spine surgery between 2009 and 2018 with preoperative cervical MRI and CTA exams (≤12 mo apart) were included. T2-weighted axial MRIs at C3 were used to measure FI and fCSA in 5 bilateral muscle groups: sternocleidomastoid (SCM), anterior, posteromedial (PM), posterolateral (PL), and trapezius (TP). Carotid stenosis was measured on CTA using semiautomated software. Correlations between muscle parameters and stenosis were analyzed with Spearman correlation and multivariable regression, adjusted for age, BMI, and sex. RESULTS: Mean stenosis was significantly associated with FI in all muscle groups, including SCM (P=0.001), anterior (P=0.022), PL (P=0.031), PM (P=0.003), and TP (P=0.001). Maximum stenosis was associated with reduced fCSA in SCM (P=0.032) and anterior (P=0.032), as well as FI in SCM (P=0.005), TP (P=0.006), and PM (P=0.001). CONCLUSIONS: This is the first study linking CAS with cervical muscle atrophy, pointing toward vascular health's potential role in muscle degeneration and the need for further research into vascular and musculoskeletal health interplay.