Relationship between muscle strength and motor function in Duchenne muscular dystrophy

Arq Neuropsiquiatr. 2016 Jul;74(7):530-5. doi: 10.1590/0004-282X20160085.

Abstract

Objective: To investigate the relationship between muscle strength and motor function and between these variables and age.

Method: Muscle strength was measured by Medical Research Council (MRC) scale and motor function, by Motor Function Measure (MFM), in 40 non-ambulatory patients. Spearman tests investigated the relationships between muscle strength, motor function and age.

Results: Total MRC and MFM scores were strongly related to each other (r = 0.94; p < 0.001), but not to age (r = -0.19, r = -0.31, respectively; p > 0.05). Strong and moderate relationships between partial muscle strength and motor function scores were found. Higher correlation coefficients were found between total scores and Dimensions 2 (axial/ proximal control) and 3 (distal control) of MFM.

Conclusion: Muscle strength and motor function are strongly correlated and seem to decrease proportionally in DMD.

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Child
  • Cross-Sectional Studies
  • Disability Evaluation
  • Disease Progression
  • Female
  • Humans
  • Male
  • Motor Activity / physiology*
  • Muscle Strength / physiology*
  • Muscular Dystrophy, Duchenne / physiopathology*
  • Neuropsychological Tests
  • Reference Values
  • Statistics, Nonparametric
  • Young Adult