Phantom Limb

The investigator-sponsored clinical study, funded by the University of California San Diego Department of Anaesthesiology, obtained three major measurements for both phantom pain and residual pain along with a change in both phantom and residual pain BioElectronics’ Model 088 device delivers a pulsed shortwave therapy. (Credit: Towfiqu barbhuiya on Unsplash) US-based medical technology products developer BioElectronics has announced the publication of a study using its pulsed shortwave therapy device to treat phantom and residual limb pain. The study is titled “Treating intractable postamputation pain with wearable, non-invasive, non-thermal, pulsed shortwave therapy: a randomized, double-masked, sham-controlled, crossover pilot study”. It was an investigator-sponsored clinical study, funded by the University of California San Diego Department of Anaesthesiology. In the study, patients initially wore BioElectronics’ Model 088 device, with about half of the patients wearing the sham device, on the residual part of the limb for 28 days. After 28 days, the patients started wearing the opposite device (the sham group) wore the active device, and the treatment group wore the sham device, for the next 28 days. The study obtained three major measurements for both phantom pain and residual pain along with a change in both phantom and residual pain before, during, and after each 28 days. The researchers presented the findings in a series of graphs over time depending on whether the patient was wearing the sham or active device. Patients wearing sham device reported no change in the median phantom limb pain or pain in the residual limb, and no median change in their global assessment of pain. In contrast, patients wearing active device reported a 40% to 50% decrease in the median measures for both average and worst residual and phantom limb pain by the seventh day, which continued through day 28. Most patients wearing the active device reported the highest level of change in residual pain by day 21, and this continued through day 28. The researchers conclude that the study identified beneficial treatment effects associated with using BioElectronics’ Model 088 in the setting of a low-cost and low-risk intervention. Based on the results, the medical device maker aims to pursue qualified distribution partners to market and sell its unique pulsed shortwave device.

WEDNESDAY, Jan. 10, 2024 -- For patients undergoing amputation, targeted muscle reinnervation (TMR) at the time of amputation improves pain scores and reduces the rate of neuroma formation, according to a study published in the January issue of Plastic and Reconstructive Surgery . Evelyn G. Goodyear, from Ohio State University Wexner Medical Center in Columbus, and colleagues conducted a cross-sectional retrospective chart review involving patients undergoing TMR between 2015 and 2020 to examine symptomatic neuroma recurrence and neuropathic pain outcomes between cohorts undergoing TMR at the time of amputation (acute) versus TMR following symptomatic neuroma formation (delayed). One hundred five limbs were identified from 103 patients, including 73 and 32 acute and delayed TMR limbs, respectively. The researchers found that 19 and 1 percent of the delayed and acute TMR groups had symptomatic neuromas recur in the distribution of original TMR, respectively. Overall, 85 percent of patients in the acute TMR group and 69 percent of patients in the delayed TMR group completed pain surveys. Of this subgroup, significantly lower phantom limb pain Patient-Reported Outcome Measurement Information System (PROMIS) pain interference, residual limb pain (RLP) PROMIS pain intensity, and RLP PROMIS pain interference scores were reported by acute TMR patients versus delayed TMR patients. "These results highlight the promising role of TMR in the prevention of neuropathic pain and neuroma formation when performed at the time of amputation," the authors write. Abstract/Full Text Disclaimer: Statistical data in medical articles provide general trends and do not pertain to individuals. Individual factors can vary greatly. Always seek personalized medical advice for individual healthcare decisions. Posted January 2024 More news resources FDA Medwatch Drug Alerts Daily MedNews News for Health Professionals New Drug Approvals New Drug Applications Drug Shortages Clinical Trial Results Generic Drug Approvals Subscribe to our newsletter Whatever your topic of interest, subscribe to our newsletters to get the best of Drugs.com in your inbox.

“We are able to produce sensations as long as the spinal cord is intact,” said Lee Fisher, Ph.D., senior author of the study. “Our approach has the potential to become an important intervention for lower-limb amputation and, with proper support from industry partners, translated into the clinic in the next five years." After racking up more than 30 years’ worth of experience in treating chronic pain, spinal cord stimulators have recently begun to expand their remit. Even as the devices continue to tack on new indications across various forms of pain, researchers are now studying the use of the technology in restoring mobility and limb function after a stroke, paralysis or other injuries. In the latest such example of that work, a study published Thursday in Nature Biomedical Engineering tasked spinal cord stimulation tech with improving the connections between the brain and a prosthetic foot in lower-limb amputees. The proof-of-concept study—which included just three participants and was led by researchers from the University of Pittsburgh School of Medicine—proved successful, according to the study’s authors. The result paves the way for further clinical trials examining a potential new use for spinal cord stimulators. In the study, the researchers rigged a standard spinal cord stimulation system to deliver its sensory signals—via electrodes implanted over the spinal cord in the lower back—as the participants stood or walked on their prosthetic legs. The level of stimulation was programmed to automatically change with the amount of pressure being exerted on the leg, based on transmissions from wireless sensors embedded into a shoe insole underneath the prosthetic foot. The system proved to be an accurate mimic of the sensations associated with walking and standing, supported by marked improvements in the participants’ balance and stability. According to the study, one participant experienced a 19-point improvement on the 100-point Sensory Organization Test, which assesses balance control. In addition, one participant saw their score on the 30-point, stability-focused Functional Gait Assessment improve by five points. On top of the improved sensory connections between the participants and their prosthetic devices, the system also helped to reduce the phantom limb pain associated with their amputated limbs. Altogether, the trio of patients reported an average reduction of 70% in their phantom limb pain—a particularly notable achievement, according to the researchers, since that form of pain is very common among lower-limb amputees and often doesn’t respond to standard pain medications. In a Pitt press release, the researchers highlighted the fact that their system was created using commercially available technologies already widely used by doctors. “We are leveraging those technologies to produce meaningful improvement in function and reduction of pain,” said Lee Fisher, Ph.D., senior author of the study and an associate professor of physical medicine and rehabilitation at Pitt. “That’s exciting, and we’ve been building it for a while.” They also noted that the system proved successful across individuals who’d undergone amputation for various reasons, as two of the participants’ amputations stemmed from diabetic peripheral neuropathy, while the third’s was a traumatic case. “We are able to produce sensations as long as the spinal cord is intact,” Fisher said in the release, adding that that broad accessibility means the system could potentially be available sooner than later: “Our approach has the potential to become an important intervention for lower-limb amputation and, with proper support from industry partners, translated into the clinic in the next five years."