Peripheral nerve stimulation - Outcome Medical of Georgia

J.N. Campbell and I. M. Longdirected at the assessment of five variablesI. Each patientsown impression of howmuch pain relief he was receiving fromuse of the stimulator device2. Patternsof drug use3. Sleeping habits4. Activity level5. Psychological well-being.In addition inquiriesas to patternsstimulator use and adverse effectswere made.Follow-up information was also obtainedon nine of 10 patientswith PNS implantationdone at the University of Minnesota. Patientchartsandinformation obtained from the patientspersonal physician were used assourcesof thisinformation.Summary of PatientsJohnsHopkinsHospital Seriessummaryof the resultsfor each patientis contained in Table along with thepatientsdiagnosistype of stimulator implanted and length of follow-up period. Anexcellent result is defined by the followingcriteriaI. The patient must continue to require theuse of the stimulator for pain relief thusallpatientswithofspontaneousremission are excluded. Only one patient had spontaneousremission andthispatient was consideredtreatment failure by other criteria.2. Analgesic use must be confined to occasional use of Tylenol acetaminophen oraspirin.3. All patientsmust have been able toresume their usual occupation or at lcast beactive at level compatible with their neurological deficit.4. All patientswho previously had beendepressed because of their pain must have hadan improvement in mood.5. Sleep disturbance previously associatedwith pain must have ceased.6. Each patient must have felt that use ofthe peripheral nerve stimulator providedmore than 50% relief of his pain.Of the 23 patientsfour were judged to havehad excellent results. Another five patientsmet some of these criteria and were judged tobe partial successes. The remaining 14 patientswere treatment failures. Eleven of thetreatmentfailuresoccurred in patientswithlow back pain syndrome with sciatica or painfrom metastatic disease. One of the treatmentfailureswas in patient Case who had hadtraumatic amputation of hs thumb withresulting dysesthesias.Trialsof percutaneousstimulation preoperatively had failed torelieve his pain however because of hisdesperate situation brachial plexusstimulator was implanted although thechancefor successwas thought to be poor.One of the four partial successpatientsCase had had nerve trauma in the handand had undergone number of handoperations. He had two distinct typesof painthe worse being sharp jabbing pain and theother burning dysesthesia. The stimulatorrelieved the former pain and allowed him toreturn to work. Subsequent to the stimulatorimplantation he had sympathectomy andinternal neurolysisof the median nerve whichhas relieved his second type of pain. He isnow able to resume normal life without useof analgesicsbut requiresthe use of thestimulator to control the sharp jabbing painto which he is still subject.Another partial successwas patient whohad had excellent resultsfor monthsbutthen developed an incomplete radial nervepalsy and partial return of pain in the areasdistal to the brachial plexusstimulationdevice. Thispatient is currently in the hospital undergoing diagnostic evaluation. Theother partial successeswere in patientswithlow back pain sciatica tvho claimed substantial pain relief with use of the stimulatorbut who were unable to resume normal livesbecause of remaining pain.Two of the excellent resultsoccurred in patientswith peripheral nerve trauma which hadfailed to improve despite multiple operations. Another was in patient with brachialneuritissecondary to radiation therapy forbreast carcinoma. The fourth case was inpatient who continued to have severe armpain following removal of cervical rib causing brachial plexuscompression.There was one infection which occurred inthe area where the receiver had been implanted on the anterior chest wall. The patientCase had had radical mastectomyandradiation therapy to thisarea and the infection probably resulted from poor healing. Shehas done well after relocation of the receiver.There was one noninfectioustissue reaction.Thiscomplication presumably reflectsanidiosyncratic reaction to the PNS implant as694J. iVcurosurg. Volume 45 lkcenbcr. /9763016