Background: While new therapies are continuously introduced to treat muscular dystrophy, current assessment tests are challenging to quantify, cannot be used in non-ambulatory patients, or can de-motivate pediatric patients. We developed a simple, engaging, upper-limb assessment tool that measures muscle strength and fatigue in children, including children with muscular dystrophy. The device is a bio-feedback grip sensor that motivates children to complete maximal and fatiguing grip protocols through a game-based interface. Methods: To determine if the new system provided the same maximum grip force as what is reported in the literature, data was collected from 311 participants without muscle disease (186 M, 125 F), ages 6 to 30, each of whom played the four minute grip game once. We compared maximum voluntary contraction at the start of the test to normative values reported in the literature using Welch’s unequal variances t-tests. In addition, we collected data on a small number of participants with muscle disease to determine if the assessment system could be used by the target patient population. Results: Of the 311 participants without muscle disease that started the test, all but one completed the game. The maximum voluntary contraction data, when categorized by age, matched literature values for hand grip force within an acceptable range. Grip forced increased with age and differed by gender, and most participants exhibited fatigue during the game, including a degradation in tracking ability as the game progressed. Of the 13 participants with muscle disease, all but one completed the game. Conclusions: The study demonstrated the technical feasibility and validity of the new hand grip device, and indicated that the device can be used to assess muscle force and fatigue in longitudinal studies of children with muscular dystrophy.
Bibliographical noteFunding Information:
The authors thank Allison Schmitz, Bhargavi Rangan, Dena Sloan, Elsa Hauschildt, Ibrahim Yekinni, Lyndsey Calvin, Natalie Vig, Rachel Anderson, Samantha Lee, Stuart Bennett and Vikram Katti, all University of Minnesota students who spent long hours at the 2018 Minnesota State Fair collecting data. We also thank the University of Minnesota Driven to Discover Research Facility staff for facilitating the data collection process. We thank our clinical partners Joline Dalton, Peter Karachunski, and Molly Stark for helpful discussions regarding the unmet clinical need.
This study was funded by grants from the Greg Marzolf Jr. Foundation.
© 2021, The Author(s).
- Muscle fatigue
- Muscle force assessment
- Muscular dystrophy
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't