ORLANDO, Fla. — The use of Coapt pattern recognition could make prosthesis control more intuitive, according to a speaker at the American Academy of Orthotists and Prosthetists Annual Meeting and Scientific Symposium, here.
Jack Uellendahl, CPO, said pattern recognition can simultaneously record all muscle activity in the residual limb of a user and classify patterns of associating user intent.
He tested the use of pattern recognition with the Coapt Complete Control System (Coapt Engineering), using 11 patients – nine patients with acquired amputations, two patients with congenital amputations and three patients with targeted muscle reinnervation.
The system is equipped with eight pairs of electrodes and a single reference and allows individual electrode contacts to be deactivated to one channel or shared on two or more channels. Electrode array can also be uniformly placed or targeted over specific active muscles, and the user can recalibrate the system when needed.
“Overall, multiple device control is simplified by elimination of cumbersome mode switching,” Uellendahl said. “Patients with targeted muscle reinnervation may even find the Coapt easier to use than a conventional system.”
There are some limitations, he said. Grip patterns cannot be accessed using pattern recognition, there is no simulation control and the use of many electrodes can be difficult on shorter limbs. In addition, the hardware needs additional space in the prosthesis; there could be additional costs; and muscle signals are required, potentially making brachial plexus injuries and similar lack of active muscle contractions unsuccessful.
There is also learning curve with this technology, Uellendahl added, but said with user training and further research, many of these obstacles can be overcome. – by Shawn M. Carter
Uellendahl J. Paper #F2. Presented at: American Academy of Orthotists and Prosthetists Annual Meeting and Scientific Symposium; March 9-12, 2016; Orlando, Fla.
Disclosure: Uellendahl reports he is an employee of Hanger Clinic.