Surgical prevention of terminal neuroma and phantom limb pain: a literature review

The incidence of extremity amputation is estimated at about 200,000 cases annually. Over 25% of patients suffer from terminal neuroma or phantom limb pain (TNPLP), resulting in pain, inability to wear a prosthetic device, and lost work. Once TNPLP develops, there is no definitive cure. Therefore, there has been an emerging focus on TNPLP prevention. We examined the current literature on TNPLP prevention in patients undergoing extremity amputation. A literature review was performed using Ovid Medline, Cochrane Collaboration Library, and Google Scholar to identify all original studies that addressed surgical prophylaxis against TNPLP. The search was conducted using both Medical Subject Headings and free-text using the terms “phantom limb pain,” “amputation neuroma,” and “surgical prevention of amputation neuroma.” Fifteen studies met the inclusion criteria, including six prospective trials, two comprehensive literature reviews, four retrospective chart reviews, and three case series/technique reviews. Five techniques were identified, and each was incorporated into a target-based classification system. A small but growing body of literature exists regarding the surgical prevention of TNPLP. Targeted muscle reinnervation (TMR), a form of physiologic target reassignment, has the greatest momentum in the academic surgical community, with multiple recent prospective studies demonstrating superior prevention of TNPLP. Neurorrhaphy and transposition with implantation are supported by less robust evidence, but merit future study as alternatives to TMR.

Utilizing an Augmented Reality System to Address Phantom Limb Syndrome in a Cloud-Based Environment

Phantom Limb Syndrome (PLS) is the perception of sensations, often including chronic intense pain localized to the site of an amputated or denervated limb. This syndrome is relatively common in amputees; the pain often reflects the amount of pre-amputation pain, and is often refractory to excision of amputation neuroma, rubbing, electrical stimulation, peripheral nerve or spinal blocks, narcotics, and sympathectomy (Alviar et al., 2011). Mirror therapy, a present method of rehabilitation, is estimated to be only 60% effective in upper limb amputees while also requiring expensive equipment and monitoring by a caretaker or technician. This paper is aimed at designing an affordable, effective, and accessible alternative solution to address the rehabilitation challenges associated with PLS. Using the power of Augmented Reality (AR) coupled with open source software, such as Unity3D and Vuforia, and commonly used devices like cellphones and computers, the prototype can read muscle activity and create an onscreen image of a virtual hand in place-of the individual's lost hand and can mimic basic hand movements through the use of an AR camera. Due to the limited processing power present within most cellphones, the solution is being refined to capitalize on Cloud computing. In doing so, the hand model can be rendered offsite and streamed directly to the phone, resulting in a higher equality image. The efficacy of this solution has not yet been tested on human subjects by virtue of legal restrictions. This system is currently being forwarded to qualified individuals who have the necessary credentials to perform clinical trials in a certified lab environment.