Optimizing Hand Crank Configuration for Therapeutic Use of Amtrykes® for Children with Upper Extremity Motor Deficits

Abstract

Objective The purpose of this research study was to create a model to assist therapists, that determines the optimal positioning of the hand cranks when fitting a child for an AmTryke® with a disability that limits upper body strength, such as a brachial plexus injury. Method A fitting model was developed by testing the amount of force required to start moving the hand cranks on the AmTryke® when various amounts of weight were applied to the seat of the device. The data collected inserted into a table. A questionnaire developed and emailed to a convenient sample of pediatric physical and occupational therapists. Results Data from the fitting model display a linear growth in the amount of force required as weight increases. Data also showed that as the length of auxilliary hand crank is increased, the amount of force required decreases. Results from the survey indicate that the majority of participants have not used the AmTryke® in practice. Conclusion Data reveals that the greater the weight of the rider, the more force required. The longer the hand crank, the less force required. This data contributes to a manual for therapists to use when determining which arrangement will create optimal use of the AmTryke® for a child. The survey suggests that occupational and physical therapists within the convenience sample used, are not using the AmTryke® as a therapeutic intervention. While the low response rate in this study precludes generalization, this information is important to guide further study as well as to shape efforts to increase occupational and physical therapist's prevalence of use of the AmTryke® in a pediatric setting.