Nicholas Langhals, Ph.D., Paul Cederna, MD
There are 1.7 million people living with limb loss in the U.S., increasing by 185,000 each year. All of these amputees will develop neuromas, or large, tangled bundles of nerve and scar tissue, due to the untreated nerve division and/or trauma at the amputation site. Of patients with neuromas, close to 25% will suffer from debilitating neuroma pain. It is well documented that neuroma pain leads to prosthesis abandonment due to compression of neuromas by the prosthetic socket. Currently accepted treatments focus on relieving symptoms without addressing the biology of a regenerating peripheral nerve, resulting in some alleviation for only 3-12 months. Repeated treatments, loss of productivity, and side effects of medications create increasing healthcare expenditures and reduce quality of life.
Plastic Surgery Faculty Paul Cederna, MD and Melanie Urbanchek, PhD, and Biomedical Engineering Faculty Cynthia Chestek, PhD, have developed a novel technology for recording neural signals as an interfacing modality between amputees and prosthetic limbs. Their strategy is to provide a new home for regenerative nerves by grafting a piece of denervated muscle to the end of the nerve. As the muscle degenerates and regenerates, it releases trophic factors that encourage neural regeneration. These regenerating muscle fibers serve as new home targets for the injured nerves and therefore prevent neuromas from forming. The team has validated this concept in 500+ rodents for up to 20 months. However, the current strategy of constructing these interfaces individually, by hand, requires substantial technical skill and procedure time, which will likely hinder clinician adoption of the technology.
Drs. Cederna, Urbanchek, and Chestek teamed up with Plastic Surgery Faculty Dr. Nicholas Langhals, colleagues Grant Kruger, PhD and Albert Shih, PhD, and students Jeffrey Plott and Jordan Kreda, in this Coulter project to develop a prototype surgical tool that creates appropriate, uniform sizes of muscle and affixes them to the end of the nerve. Prototype development was informed by clinical feedback on the form and function of the tool, with the goal of reducing procedure time by approximately 60-70%. The surgical tool design parameters and efficacy were validated using an acute pig model. Following completion of this work, this technology was well-positioned for license to an existing entity.