Effects of Myoelectric Channel Count and Targeting for Upper Limb Prosthetic Control

Conditions

• Amputation
• Amputation, Congenital
• Amputation, Traumatic
• Amputation; Traumatic, Arm: Forearm, Between Elbow and Wrist
• Prosthesis User
• Upper Limb Amputation Below Elbow (Injury)

Eligibility Criteria

Sex

ALL

Age

18 Years - N/A

Healthy Volunteers

Not accepted

Interventions

• Experimental socket with 4 untargeted channels active — DEVICE
  Participants will utilize the experimental socket made with untargeted EMG channels. Untargeted sites will ideally be located by creating a band of electrode pairs at the largest muscular circumference distal to the elbow. Only 4 channels will be active during this condition.
• Experimental socket with 8 untargeted channels active — DEVICE
  Participants will utilize the experimental socket made with untargeted EMG channels. Untargeted sites will ideally be located by creating a band of electrode pairs at the largest muscular circumference distal to the elbow. Only 8 channels will be active during this condition.
• Experimental socket with up to 16 untargeted channels active — DEVICE
  Participants will utilize the experimental socket made with untargeted EMG channels. Untargeted sites will ideally be located by creating a band of electrode pairs at the largest muscular circumference distal to the elbow. All16 channels (or the maximum number of channels based on limb size) will be active during this condition.
• Experimental socket with 8 targeted channels active — DEVICE
  Participants will utilize the experimental socket made with targeted EMG channels. This socket will follow Coapt's clinical instructions for targeted site location to identify and mark locations for 8 targeted EMG channels.
• Coapt EMG Cuff — DEVICE
  This device is the commercially available Coapt EMG Cuff. This armband cuff with electrodes can be strapped onto the user's arm to connect with the Coapt app and play virtual games with their EMG signals.

Study Details

The goal of this clinical trial is to systematically evaluate whether or not two commonly held fundamental assumptions for pattern recognition control translates to functional performance when tested on individuals aged 18 years or older with upper limb absence at the transradial level while wearing a physical prosthesis. The specific aims of this study are: 1. To evaluate the effect of changing untargeted myoelectric channel count on the functional performance of transradial prosthesis users wearing a fully functional prosthesis via functional outcomes measures such as the Box and Blocks test. 2. To evaluate the effect of changing myoelectric channel targeting of a fixed number of myoelectric channels on the functional performance of transradial prosthesis users wearing a fully functional prosthesis via functional outcomes measures such as the Box and Blocks test. Researchers will perform a randomized crossover study to compare system configurations with different number of sensor channels and with various strategies for sensor placement on the limb. Participants will be assigned to a random test sequence that includes the following four different EMG channel conditions: Condition A: 4 untargeted channels Condition B: 8 untargeted channels Condition C: Up to 16 untargeted channels Condition D: 8 targeted channels Researchers will evaluate the effects of changing myoelectric channel counts on the functional prosthesis performance of individuals with transradial limb loss via functional outcome measures. Participants will: * Attend up to 5 in-lab sessions that are expected to last 4 hours. * Conduct site visits every 1-2 weeks to complete functional and self reported outcome measures with each condition. * Play virtual games with the Coapt Cuff for 15 minutes a day, 3 days a week in between visits.

Key Dates

Start date

Oct 31, 2025

Status verified

Sep 2025

Primary completion

Jun 30, 2026

Completion

Jun 30, 2026

Study Design

Enrollment

32 participants (estimated)

Allocation

RANDOMIZED

Intervention model

CROSSOVER

Primary purpose

BASIC_SCIENCE

Arms

• Experimental: Condition A: 4 untargeted channels
  The 4-channel untargeted condition (Condition A) will utilize every fourth channel, and their location will be targeted at positions that are 'on the 45s' when examining a cross section of the forearm with the elbow bent to 90 degrees and the thumb pointed up. This condition is conducted and completed during a site visit. Outcome measures will be conducted to assess functional outcomes and self-report measures.
• Experimental: Condition B: 8 untargeted channels
  The 8-channel condition (Condition B) will use the same channels as the 4-channel condition but add the four channels that bisect the original four channels. This condition is conducted and completed during a site visit. Outcome measures will be conducted to assess functional outcomes and self-report measures.
• Experimental: Condition C: Up to 16 untargeted channels
  The 16-channel untargeted condition (Condition C) will utilize all 16 electrodes. Due to different limb sizes a full singular ring of 16 channels may not be possible on all human subjects. In these situations, the clinicians fabricating will use their best clinical judgement in order to fit as many electrode channels as possible onto the arm. If there is no reasonable way to fit 16 channels within the socket, then the maximum possible number of channels will be placed in the socket and the "16-channel" condition will be completed with the maximum number of available channels. This condition is conducted and completed during a site visit. Outcome measures will be conducted to assess functional outcomes and self-report measures.
• Active Comparator: Condition D: 8 targeted channels
  This socket will use 8 targeted EMG channels identified and marked by the study prosthetist using Coapt's clinical instructions for identifying electrode sites. This condition is conducted and completed during a site visit. Outcome measures will be conducted to assess functional outcomes and self-report measures.
• Other: At-home Pattern Recognition Practice
  The subject will use a commercially available EMG Coapt Cuff to practice pattern recognition while at home between study visits. They will be asked to play virtual games with the Coapt Cuff for 15 minutes a day, 3 days a week in between visits. The time between visits will be based on scheduling availability of the participant and study team but is expected to be approximately 1-2 weeks.

Primary Outcome Measure

The Assessment of Capacity for Myoelectric Control (ACMC) [ Time Frame: 4 hours ]

Central Contacts

• Brianna Rozell
  774-233-0876
  [email protected]
• Craig Kelly
  774.233.0878
  [email protected]

Locations (2)

Find similar trials in Chicago, IL

Related Studies

• A Novel Approach to Upper Extremity Amputation to Augment Volitional Control and Restore Proprioception
  Recruiting · Brigham and Women's Hospital · Bethesda, Maryland
• AMI Construction in Lower Extremity Residual Limbs
  Recruiting · Brigham and Women's Hospital · Bethesda, Maryland
• Powered Prosthesis for Use With TF Osseointegration Recipients
  Recruiting · Shirley Ryan AbilityLab · Chicago, Illinois
• Understanding How Powered Componentry Impacts K2-Level Transfemoral Amputee Gait
  Recruiting · Shirley Ryan AbilityLab · Chicago, Illinois