AURORA, CO — Can sonography be a useful tool in evaluating changes due to disease progression or therapeutic interventions in multiple sclerosis (MS) patients? A new VA study suggested it could be.
“Neurologically-based muscle weakness is a common symptom in people with multiple sclerosis (MS), who may also exhibit muscle morphology changes and intrinsic muscle dysfunction,” according to a study in Multiple Sclerosis and Related Disorders. “Diagnostic ultrasound (sonography) is a non-invasive, inexpensive, and clinically feasible method to measure muscle morphology.”1
The authors from the University of Colorado Anschutz Medical Campus and the Rocky Mountain Regional VAMC, both in Aurora, CO, sought to investigate possible asymmetries in lower limb muscle morphology and performance in MS patients and assess the relationships of muscle morphology measures with individual patient characteristics, muscle performance and functional mobility.1
The cross-sectional study was conducted at the Washington, DC VAMC and included 29 veterans with MS—52% female, 79% African American, 48.6 ± 11.2 years old, Mean Expanded Disability Status Scale: 3.6 ± 1.4. The participants completed seated knee extension isokinetic strength and power tests, functional assessments (Timed 25-Foot Walk-T25FW, 5-Times Sit-to-Stand-5STS), and quantitative B-mode ultrasound image acquisition of the rectus femoris muscle to derive morphology measures (thickness and echogenicity).
The limb with weaker knee extension strength was identified as the more-involved limb, and differences between the more and less-involved limb were quantified using a T-test for all muscle morphology and muscle performance measures. The researchers evaluated relationships between muscle morphology and patient characteristics, muscle performance and functional mobility.
The results indicated that the rectus femoris thickness from the more-involved limb was lower (p<0.001) than that of the less-involved limb, although echogenicity was not different between the two limbs (p=0.147). The study determined that rectus femoris thickness of the more-involved limb was directly related to age (r=-0.63, p<0.001), muscle strength (r=0.53, p=0.003) and power (r=0.53, p=0.003), and gait speed (r=0.42, p=0.024. Echogenicity was positively associated only with muscle strength (r=-0.46, p=0.013) and power (r=-0.50, p=0.006), however.
“Together, rectus femoris thickness and echogenicity of the more involved limb explained 44% and 48% of the variance in muscle strength and power, respectively (p<0.001),” the authors wrote.
Conclusion
This study supports the ability of sonography to measure muscle morphology in people with MS, identify asymmetries, and quantify associations with important clinical correlates. Compared with more invasive and costly alternatives, sonography is a clinically feasible, relatively low-cost tool that can be used to assess muscle morphology in people with MS. Further research is warranted to determine the potential clinical utility of sonographic measures of muscle morphology in evaluating changes due to disease progression or therapeutic interventions in this population.
- Mañago MM, Seamon BA, Boncella KL, Wallin MT, Maloni H, Hoover B, Blackman MR, Harris-Love MO. Ultrasound measures of muscle morphology in people with multiple sclerosis are associated with muscle performance and functional mobility. Mult Scler Relat Disord. 2023 May 10;75:104759. doi: 10.1016/j.msard.2023.104759. Epub ahead of print. PMID: 37192587.