Phantom limb pain can be a frustrating challenge for amputees. Phantom motor execution, a new form of rehabilitation, could put an end to it for good
Physical rehabilitation that involves the fitting of a prosthesis is not without its growing pains. The road to being fully mobile and functional can sometimes be challenging. The speed bumps that could hinder a patients’ physical restoration include delayed wound healing, falls, issues with socket comfort, and funding. However, none are as frustrating and difficult to treat as phantom limb pain.
HPCSA-registered trauma counselor Elma Hofmeyr recently visited our practice to introduce us to an exciting advancement in the field. Having dealt closely with amputees, she has a special interest in relieving amputees of this often debilitating problem.
Numerous solutions to treat phantom limb pain, including medication, mirror therapy and prosthetic treatment, have been tried and tested. One seems to stand out, though. It’s called phantom motor execution (PME) and it brings new hope to amputees suffering from phantom limb pain by facilitating the treatment through a device called Neuromotus.
The concept, closely resembling mirror therapy, is based on augmented reality as opposed to virtual reality. You can “look” at the real world in real time on a screen, but it is augmented or changed. Patients sit in front of a screen, almost like the selfie mode on a phone, and are able to see themselves. However, a virtual limb is attached to the end of the residual limb.
Patients are able to use the residual limb’s muscles to move the virtual limb and perform basic physical tasks like flexing or extending and pronating or supinating, and control objects in a game.
This form of therapy is believed to work by exploiting competitive neuroplasticity and provide a more integral normalisation of cortical, subcortical and spinal circuits compared with interventions that don’t enable integration of sensory and motor information.
PME aims to reactivate the original central and peripheral circuitry involved in the motor control of the limb along with increasing the dexterity of stump muscles. The PME hypothesis entails that the training of phantom movements induces gradual neural changes similar to the changes found when perfecting a motor skill.
These purposefully induced neural changes disentangle pain-processing circuitry through competitive plasticity according to a 2018 study by Dr Max Ortiz Catalan and fellow researchers from Chalmers University of Technology in Sweden.
What’s more, in a 2014 study, also by Ortiz Catalan, one patient with chronic phantom limb pain who had
shown resistance to a variety of treatment for 48 years, showed satisfactory results after PME treatment with Neuromotus.
After the treatment, he reported that the sustained level of pain had been reduced to pain-free periods and that he was able to move his limb phantom pain free. In another 2014 study by Ortiz Catalan, 14 patients received 12 treatments of PME and, by the end of the treatment period, showed clinically significant improvements.
PME with Neuromotus is still in the early research phases, but it certainly poses a promising solution to many amputees suffering from phantom limb pain and gives new meaning to the words “hot-wiring your nervous system”.
Heinrich Grimsehl is a prosthetist in private practice and a member of the South African Orthotic and Prosthetic Association (SAOPA). email: info@hgprosthetics.co.za
