Quantitative assessment of postural stability in individuals with degenerative cervical myelopathy compared with healthy controls.

Abstract

Objective: The aim of this study was to quantitatively assess postural stability using force plate center of pressure (COP) parameters in a large sample of Chinese patients with degenerative cervical myelopathy (DCM), compare the results with healthy controls, and examine correlations between balance measures (COP parameters, brief Balance Evaluation Systems Test [Brief-BESTest] scores) and clinical assessments, including MRI findings.

Methods: This cross-sectional observational study included 141 patients with DCM (diagnosed from June 2022 to May 2024) and 141 age- and sex-matched healthy controls. Postural balance was assessed using COP parameters and Brief-BESTest scores. Clinical assessments included the modified Japanese Orthopaedic Association (mJOA) score, 10-second grip and release test, 10-second step test, and Hoffman sign. MRI findings included the cross-sectional area (CSA) of the spinal cord at the most compressed level and increased signal intensity on T2-weighted images. COP parameters were compared between patients with DCM and controls, while correlations between COP parameters and Brief-BESTest scores and clinical/MRI findings were analyzed within the DCM cohort.

Results: Patients with DCM had significantly greater COP values in path length, ellipse area, average velocity, and average acceleration compared with controls (all p < 0.001), indicating notable balance impairment. Brief-BESTest scores and COP parameters showed moderate to strong correlations with mJOA scores (ρ = 0.310-0.768) and varied significantly across mJOA severity levels (p < 0.01). Moderate correlations were observed between CSA and balance measures (ρ = 0.212-0.487), while increased signal intensity on MRI had limited impact. Both the grip and release and step tests also correlated moderately with balance measures (ρ = 0.245-0.640).

Conclusions: Patients with DCM showed substantial balance impairment compared with healthy controls, with COP parameters and Brief-BESTest scores correlating well with mJOA scores, highlighting their utility in balance assessment. Moderate associations between CSA and balance suggest that structural MRI changes are relevant to postural stability in DCM. Future research could enhance balance assessment by integrating additional objective tools, such as motion analysis, providing a more comprehensive understanding of the effects of DCM on postural control.