# Association between quantitative cervical cord compression metrics and upper extremity impairments in degenerative cervical myelopathy: a cross-sectional study

## TL;DR

This study finds that specific imaging metrics of cervical cord compression correlate with upper limb impairments in patients with degenerative cervical myelopathy.

## Contribution

The study identifies specific imaging biomarkers that correlate with upper extremity dysfunction in cervical myelopathy patients.

## Key findings

- Cervical cord cross-sectional area, anterior-posterior width, and compression ratio correlate with upper extremity motor function scores.
- Critical cutoff values for these metrics can help distinguish patients with upper extremity motor dysfunction.
- Imaging parameters of cord compression are potential biomarkers for assessing and planning treatment in DCM.

## Abstract

Degenerative cervical myelopathy (DCM) can lead to series of neurological dysfunction. This study aims to investigate the relationship between the compressed cervical cord and the severity of upper extremity impairments in DCM patients.

47 single-level DCM patients were included from January 2023 to May 2025. Cross-sectional area (CSA), anterior-posterior width (APW), right-left width (RLW), and compression ratio (CR = APW/RLW) of the most compressed cervical cord were measured. The modified Japanese Orthopedic Association (mJOA) scale, visual analog scale (VAS), neck disability index (NDI) and the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) were used to assess upper extremity impairments. Patients were categorized into two groups based on the presence of upper extremity motor dysfunction of mJOA score. Correlation analysis was used to determine the associations between the characteristics of the cervical cord compression and upper extremity impairments. Receiver operating characteristic (ROC) curve analysis was conducted to identify critical values.

In patients with single-level DCM, CSA, APW, and CR of the compressed cervical cord were correlated with upper extremity outcomes, including the mJOA subscore for upper extremity motor function (ρ = 0.54, 0.54, and 0.48; P < 0.05), VAS score for upper extremity (ρ = −0.32, −0.44, and −0.46; P < 0.05), and JOACMEQ subsection for upper extremity function (ρ = 0.33, 0.30, and 0.33; P < 0.05). ROC analysis identified critical cutoff values (CSA < 52.6 mm2, APW < 4.5 mm, and CR < 31.4%) that effectively discriminate upper extremity motor function in DCM patients.

In DCM patients, the imaging parameters of the compressed cervical cord are related to upper extremity deficits, suggesting that these characteristics could serve as potential biomarkers in diagnostic assessments and treatment planning.