A Feasibility Study to Assess Safety and Functionality of Implantable Myoelectric Sensors for Upper Extremity Prosthetic Control in Transradial Amputees
Overview
- Phase
- N/A
- Intervention
- Not specified
- Conditions
- Amputation, Traumatic
- Sponsor
- The Alfred E. Mann Foundation for Scientific Research
- Enrollment
- 3
- Locations
- 1
- Primary Endpoint
- Device-Related Serious Adverse Events
- Status
- Completed
- Last Updated
- 9 years ago
Overview
Brief Summary
This study will evaluate the feasibility of using implanted myoelectric sensors (IMES) to control an electromechanical prosthetic wrist and hand.
Detailed Description
The study assesses the feasibility of an advanced prosthesis control system aimed at development of a more intuitive and functional prosthetic device. Tiny (2.5 mm by 16 mm) Implantable Myoelectric Sensors (IMES) will be implanted into the residual forearm muscles of three transradial amputee subjects. These devices wirelessly transmit electrical muscle signals to an electromechanical prosthetic wrist and hand. Following a two-week recovery from implantation of six to eight IMES into residual forearm muscles, subjects will initiate seven months of training. Subjects first train for approximately a month using a bench-top IMES system. When they receive their custom-fit IMES Prosthesis (including electromechanical wrist and hand) subjects initiate six months of additional training. Subjects will then be given the option to use the IMES Prosthesis for another sixteen months. The usability and functionality of the prosthetic system will be evaluated throughout the study.
Investigators
Eligibility Criteria
Inclusion Criteria
- •Patient is a health care beneficiary at the Walter Reed National Military Medical Center.
- •Patient has transradial amputation with one-third or greater residual forearm length as determined by the contralateral side.
- •Patient's residual forearm anatomy (based on number and size of residual muscles) will support the implantation and control of at least six IMES (in the opinion of the Investigator). This criterion will be verified during a study-specific screening test.
- •Patient is age 18 or above.
- •Patient can speak and comprehend English.
- •Patient is willing and capable of providing informed consent.
- •Patient has undergone amputee rehabilitation, including being trained to wear and use a body-powered and myoelectric prosthesis.
- •Patient reports wearing an upper limb prosthesis at least two hours per day.
- •Unilateral amputation with preserved function of the non-amputated arm; preserved function is investigator opinion as to whether the patient:
- •has the ability to independently don and doff a prosthesis,
Exclusion Criteria
- •Patient is less than three months from amputation surgery or major injury of the target residual limb.
- •Patient has major injury proximal to the level of amputation.
- •In the opinion of the Investigator, patient is prone to skin breakdown in the target residual limb.
- •Known nerve transection or palsy that may cause de-innervation of muscles in the target residual limb.
- •Known genetic neuromuscular disorder (e.g. multiple sclerosis, myasthenia gravis, muscular dystrophy).
- •Patient has a bleeding or clotting disorder.
- •Bilateral upper extremity amputation.
- •Patient has a major psychological disorder such as poorly controlled PTSD, schizophrenia, or paranoia such that cooperative status is inconsistent.
- •Patient has an active implant (e.g. pacemaker, implanted cardiac defibrillator \[ICD\], neurostimulator, drug infusion device).
- •Patients having any metal fragments or metal implants (e.g. orthopedic hardware) located within the residual forearm are excluded. The absence of metal shall be confirmed by an x-ray of the entire affected arm.
Outcomes
Primary Outcomes
Device-Related Serious Adverse Events
Time Frame: Information collected over the course of 2 years following implant of IMES
Tabulation of Device-Related Serious Adverse Events during the course of the study.
Change in Accuracy Test score
Time Frame: test conducted nine times: upon receipt and programming of custom-fit IMES prosthesis; once per month for six months of training; 1 year following implant; and 2 years following implant
The Accuracy Test requires subjects to execute a series of different hand movements using the IMES to control an electromechanical wrist and hand. Movements are chosen to demonstrate both independent and simultaneous control over the six different movements offered by the prosthesis: hand open/close, thumb adduct/abduct, wrist supinate/pronate. An occupation therapist will score the subject on each movement as follows: 0 = no movement observed; 1 = the intended movement was not observed, but unintended movements were observed; 2 = the intended movement was observed, in addition to unintended movements; 3 = the intended movement was observed. The change in Accuracy Scores across the nine tests completed will be presented. During the Accuracy Test, Electromyographic(EMG) signals transmitted by the IMES will be recorded. A video camera will record the movements of the prosthesis so that this output may be associated with the input IMES signals.
Secondary Outcomes
- Change in Box and Block Test (BBT) score(test conducted nine times: upon receipt and programming of custom-fit IMES prosthesis; once per month for six months of training; 1 year following implant; and 2 years following implant)
- Change in Southampton Hand Assessment Procedure (SHAP) test score(test conducted nine times: upon receipt and programming of custom-fit IMES prosthesis; once per month for six months of training; 1 year following implant; and 2 years following implant)
- Change in Assessment of Capacity for Myoelectric Control (ACMC) test score(test conducted nine times: upon receipt and programming of custom-fit IMES prosthesis; once per month for six months of training; 1 year following implant; and 2 years following implant)
- IMES Satisfaction Questionnaire(completed after six months of training following upon receipt and programming of custom-fit IMES prosthesis)