Related Experiment Video
Updated: Jul 5, 2025
Development of a Novel Task-oriented Rehabilitation Program using a Bimanual Exoskeleton Robotic Hand
Published on: May 20, 2020
Moving a missing hand: children born with below elbow deficiency can enact hand grasp patterns with their residual
Justin J Fitzgerald1,2,3, Marcus A Battraw4, Michelle A James5,6
1Department of Biomedical Engineering, University of California, Davis, CA, USA.
Insights
Children with unilateral congenital below elbow deficiency (UCBED) can activate residual muscles for distinct hand movements, similar to their typical limb. This motor control development offers new possibilities for prosthetic device design.
Area of Science:
- Neuroscience
- Developmental Biology
- Biomedical Engineering
Background:
- Unilateral congenital below elbow deficiency (UCBED) affects children, resulting in a missing hand and forearm limb. Existing prosthetic designs often assume limited motor control in affected muscles, impacting device functionality.
- Unlike adults with acquired limb loss, children with UCBED never developed a hand, leading to assumptions about their residual muscle actuation capabilities.
Purpose of the Study:
- To investigate the motor control capabilities of residual muscles in children with UCBED.
- To determine if children with UCBED can intentionally activate distinct muscle patterns in their affected limb.
- To inform the design of advanced prosthetic devices that utilize the full extent of children's motor control.
Main Methods:
- Ultrasound imaging was employed to study muscle activation patterns in 6 children with UCBED.
- Researchers compared muscle activation during attempted movements of the missing hand with movements of the typical limb.
- The study focused on the ability to purposefully modulate affected muscle activity.
Main Results:
- All participants demonstrated the ability to intentionally and consistently activate at least five distinct muscle patterns when attempting various missing hand movements.
- The performance of muscle activation in the affected limb was comparable to that of the typically developed limb.
- These findings indicate that distinct motor control patterns develop even without a fully formed effector limb.
Conclusions:
- Children with UCBED possess significant, distinct motor control capabilities in their residual forearm muscles.
- These motor control abilities can be leveraged for the development of more intuitive and effective prosthetic devices.
- The study highlights that motor control development persists in the absence of a normal limb effector.
Abstract:
Children with a unilateral congenital below elbow deficiency (UCBED) have one typical upper limb and one that lacks a hand, ending below the elbow at the proximal/mid forearm. UCBED is an isolated condition, and affected children otherwise develop normal sensorimotor control. Unlike adults with upper limb absence, the majority of whom have an acquired loss, children with UCBED never developed a hand, so their residual muscles have never actuated an intact limb. Their ability to purposefully modulate affected muscle activity is often assumed to be limited, and this assumption has influenced prosthetic design and prescription practices for this population as many modern devices derive control signals from affected muscle activity. To better understand the motor capabilities of the affected muscles, we used ultrasound imaging to study 6 children with UCBED. We examined the extent to which subjects activate their affected muscles when performing mirrored movements with their typical and missing hands. We demonstrate that all subjects could intentionally and consistently enact at least five distinct muscle patterns when attempting different missing hand movements (e.g., power grasp) and found similar performance across affected and typically developed limbs. These results suggest that although participants had never actuated the missing hand they could distinctively and consistently activate the residual muscle patterns associated with actions on the unaffected side. These findings indicate that motor control still develops in the absence of the normal effector, and can serve as a guide for developing prostheses that leverage the full extent of these children's motor control capabilities.
More Related Videos
06:58A Structured Rehabilitation Protocol for Improved Multifunctional Prosthetic Control: A Case Study
Published on: November 6, 2015
09:14Surface Electromyographic Biofeedback as a Rehabilitation Tool for Patients with Global Brachial Plexus Injury Receiving Bionic Reconstruction
Published on: September 28, 2019
