Published In

Rare Disease and Orphan Drugs Journal

Document Type

Article

Publication Date

10-21-2025

Subjects

Duchenne muscular dystrophy, Longitudinal lower limb contractures, Gait spatiotemporal parameters

Abstract

Aim: The absence of dystrophin in patients with Duchenne Muscular Dystrophy (DMD) causes muscle fiber necrosis and fibrosis and eventually muscle weakness and contractures. This study aimed to investigate the timing and extent of lower limb contracture development and to examine how contractures, muscle strength, and kinematic (e.g., limb position or joint movement) deviations relate to longitudinal changes in gait spatiotemporal parameters.

Methods: Seventy-five ambulatory boys with DMD participated in this prospective longitudinal study of contractures, isometric muscle strength, and gait analysis. Nonlinear mixed modeling (NLMIXED) exponential growth curve models were developed to investigate the effects of contractures, muscle strength, and kinematic deviations on longitudinal changes in gait spatiotemporal parameters.

Results: Ankle plantar flexion contractures were present as early as 4 years of age. Hip flexion contractures, assessed by the Thomas test, and knee flexion contractures, assessed by knee extension in supine, developed around 13 years of age and did not exceed ten degrees. Over time, gait speed, stride length, and cadence decreased. Statistically significant covariates for gait speed included hip flexor contracture (limitation in hip extension), hip extensor and ankle plantar flexor strength, and pelvic tilt Gait Variable Score (GVS). Plantar flexor strength was a significant covariate for stride length, while pelvic obliquity GVS significantly correlated with cadence.

Conclusion: Subtle changes in hip extensor and ankle plantar flexor strength, along with pelvic range of motion during gait, are indicators of DMD disease progression. Gait analysis, including easily accessible measures of gait speed and normalized stride length, may provide a more sensitive indicator of DMD disease progression than manual assessments of contractures and muscle strength.

Rights

© The Author(s) 2025. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, sharing, adaptation, distribution and reproduction in any medium or format, for any purpose, even commercially, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Locate the Document

http://dx.doi.org/10.20517/rdodj.2024.56

DOI

10.20517/rdodj.2024.56

Persistent Identifier

https://archives.pdx.edu/ds/psu/44194

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