Implantable Peripheral Nerve Stimulator for Treatment of Phantom Limb Pain

Abstract Chronic phantom limb painPLPhas been reported to inflict as many asof people with amputationsPLP is described as feeling like burningtwistingitchingor pressure in part of the missing limbThese painful sensations have a substantial negative impact on quality of lifepeople who suffer PLP have high rates of depressiondifficulty sleepingregular absences from workdissociation with family friendsand limited use of their prosthesesThe use of medications to alleviate PLP is only abouteffective at managing painadditionallythese medications have many undesirable side effectsOpioids are a commonly prescribed pharmacological treatmenttypically in conjuection with other medicationsNon pharmaceutical approaches to PLP management have been reported with onlysuccess ratesImplantable spinal pain stimulators have demonstrated only limited effectiveness in managing PLPthe lack of specificity in targeting effected neural tissue diminishes clinical benefitIn contrastit has been demonstrated that stimulation used to restore sensation from the missing limb is highly effective at eliminating PLPRestoring these missing sensory inputs alters central processing of peripheral sensationthereby mitigating pain from the amputated limbIn additionsensory restoration has the benefit of improving stability and embodiment of a prosthesisIn response to the need for improved treatment for PLPRipple proposes to develop an implantable neural stimulation system to provide natural and intuitive sensation for prosthesis usersRipple is experienced in printing customflexibleand highly durable implantable electrode arraysWe are confident our nerve cuff technology meets all the requirements for a sensory feedback system capable of providing consistent and controlled electrical stimulationCoupled with Ripple s multichannel implantable stimulatorwe believe this custom electrode array will offer substantial improvement over existing options to treat PLPWe have developed this implantable multichannel stimulator with the capabilites of delivering arbitrary waveform stimulation pulses on multiple independent channelswhich are features required for sensory feedback stimulationAs a system integrator on the DARPA HAPTIX projectwe have already developed a prototype implantable stimulator capable of restoring sensation from a missing limb via peripheral nerve stimulationIn Phase Iwe will finalize array architectures for evaluation in cadaver studiescomplete integration of electrodes with our implantable stimulatorconduct benchtop verification of electrical and mechanical performance in accelerated lifetime testingsend implants out for third party evaluation of system biocompatibilityand complete amonth GLP animal study to validate safety and efficacyAt the end of Phase Iwe will submit an IDE to the FDA for first in human testing of the implantable systemIn Phase IIwe will conduct asubject clinical study to test the implantable stimulation system with the clinical team at Presbyterian StLuke s Medical Center in DenverCODrGiancarlo Barolat is a world expert in neurostimulation therapy for chronic pain and DrDavid Hahn leads the Institution for Limb Preservationan advanced center specializing in amputations and complex limb surgeriesEach unilateral prosthesis user will be implanted for one year as we evaluate the safety and efficacy of this implantable device to treat PLP Narrative Chronic phantom limb pain has no effective treatment despite impacting most people following amputation and limiting quality of lifeIt has been demonstrated that peripheral nerve stimulation used to restore sensation from the missing limb is highly effective at managing phantom limb painThuswe are developing an implantable peripheral nerve stimulator with a novel peripheral nerve interface to provide a non opioid treatment for people with amputations who suffer from phantom limb pain