Decreased Gait and Function in Duchenne Muscular Dystrophy

Abstract

Duchenne muscular dystrophy (DMD) is a genetic disorder linked to chromosome Xp21, due to absence of dystrophin production. It is clinically characterized by progressive muscle weakness, fatigue, and development of joint contractures that compromise general motor functionality, mainly the gait. Objective: To characterize the motor function and decrease gait in children with DMD using the Portuguese version of the Motor Function Measure scale (MFM-P). Methods: A review of medical records including chronological age and scores from MFM-P of children with a DMD who attended at the Neuromuscular Diseases Clinic at Campinas State University (UNICAMP), Brazil was performed in this study. A total of 36 medical records of male patients with confirmed clinical diagnosis of DMD, ambulatory or not, regardless of age; excluding those with other associated diseases or other types of muscular dystrophies were selected. Data were analyzed using Kolmogorov-Smirnov and Spearman correlation statistical tests. Results: Analysis of all data collected showed that 75% of our sample had D1 scores lower than 41.02%. There was a linear relationship between the scores of D2 and D3, but no association between D2 and D1 scores was noted. D1 score was between 40% and 80% in those patients presenting D2 scores between 80% and 100%. In all cases patients with low total score presented a greater risk for loss of gait and their functionality. Conclusion: The standing posture and the postural transfers were the worst activities observed in children with DMD, with positive correlation between proximal and distal motor function. Even with high scores according MFM-P in proximal function, the children showed strong predictors for loss of gait.

Corticosteroids in Duchenne muscular dystrophy: impact on the motor function measure sensitivity to change and implications for clinical trials

“…The D1 subscore has been shown to be the most informative dimension at this stage of the disease to evaluate change with the possibility to predict the loss of walking ability. 17,19,23 D1 subscore explores not only the ability to walk but also the ability to stand and to transfer from standing to sitting, which are interesting functional abilities in this stage of the disease. Although this study should be replicated in a different cohort to improve the robustness of the results, we strongly recommend consideration of MFM as an outcome measure in clinical trials including ambulatory patients with DMD treated with corticosteroids, especially as SRM values of at least 0.8 for the D1 subscore were observed after 6 months of corticosteroid treatment, confirming that this subscore was the most sensitive to change in this population.…”