Percutaneous Stimulation Research Articles

Effects of percutaneous acupuncture stimulation on the viscoelastic properties of tendon during isometric contraction

This study aimed to investigate the effects of percutaneous acupuncture stimulation on the viscoelasticity of human tendon structures during isometric contraction. Nine healthy men participated. The experimental order was pre-test, acupuncture stimulation, and post-test. Real and sham acupuncture applications were used at the stimulus site of the medial gastrocnemius muscle (MG), and a crossover trial was performed on the same subjects at a later date. Before and after acupuncture stimulation, tendon elongation and MG aponeurosis were directly measured by ultrasonography while the subjects performed isometric plantar flexions up to the maximum voluntary contraction (MVC) followed by relaxation. The relationship between the estimated MG muscle force (Fm) and tendon elongation (L) during the ascending phase was fitted to a linear regression, the slope of which was defined as the stiffness of the tendon structures. Additionally, the ratio (%) of the area within the Fm–L loop to the area under the curve during contraction and relaxation was calculated and defined as hysteresis. Stiffness rate of change (RC) in real and sham acupuncture was 137.5±116.5% and 55.0±10.4%, respectively (p<0.05). Thus, real acupuncture demonstrated significantly higher values than sham acupuncture. The hysteresis measurement results in real acupuncture indicated a downward tendency (pre-treatment: 25.6±5.1%, post-treatment: 16.1±13.0%), while sham acupuncture indicated an upward tendency (pre-treatment: 26.5±10.9%, post-treatment: 28.4±6.9%). These results indicated that percutaneous acupuncture stimulation reduces hysteresis, enhances stiffness, and improves the viscoelasticity of tendon structures.

9. Multimodal intraoperative evoked potential monitoring (IOM) for hip surgery

Introduction The incidence of sciatic nerve palsy after hip surgery ranges from 2.7% in primary total hip arthroplasty up to 7.6% in developmental dysplasia surgery. So far, intraoperative monitoring using multimodal evoked potential for hip surgeries to assess sciatic and femoral nerves functional integrity has not been described. Material and methods Thirty patients who underwent hip surgery using IOM of sciatic and femoral nerves have been evaluated. All the patients received total intravenous anaesthesia. Multimodal IOM includes: (a) somatosensory evoked potentials (SEP) and (b) motor evoked potentials (MEP) recorded bilaterally in lower extremities limb muscles from quadriceps, tibialis anterior, gastrocnemius, peroneal and abductor hallucis bilaterally. In addition, we also have developed a new IOM technique: (c) posterior root muscle reflex (PRMR) and (d) anterior root muscle response (ARMR). To elicit PRMR and ARMR, percutaneous stimulation of cauda equine was performed by self-adhesive electrodes placed over the skin of the projection of the first and third lumbar interspinous space (anode) and over the abdomen skin of the umbilicus (cathode). A paired stimuli of identical parameters are used with an interstimulus interval of 50 ms and duration of 0.5–1 ms. The recording electrodes for PRMR and ARMR were identical as the electrodes used for recording MEPs. Results Baselines were successful in all patients. Detection of significant changes occured in eight patients (8/30, 26,6%). In six patients (6/30, 20%) changes were reversible and in two patients (2/30, 6,7%) changes were irreversible and correlated with the postoperative neurological deficit. Conclusion Multimodal IOM techniques applied to hip surgery allow identification of the momentthat may damage peripheral nerves of roots before an irreversible injury occurred and/or avoid permanent postoperative neurological deficits. PRMR and ARMR could emerge as a new intraoperative monitoring techniques to assess the functional integrity of lumbosacral plexus and nerves. These new techniques have potential to give more specific information than MEPs and SEPs.

Exercise‐induced hyperthermia exacerbates the rightward displacement in the force‐frequency relationship compared with passive hyperthermia (1104.27)

This study examined the extent to which exercise‐induced hyperthermia (ExH) influences contractile function and modulates the force‐frequency relationship, compared with passive hyperthermia (PaH). ExH was induced in ten males by cycling at 60% VO2max in 38°C conditions and PaH by sitting in a 48°C chamber. Prior to and following ExH and PaH, an 8 s train of stimulation (10, 20, 50 and 100 Hz; 2 s per frequency) and a potentiated twitch were evoked on the relaxed knee extensors via percutaneous stimulation. Core (~37.0 to ~38.5ºC) and muscle (~34.7 to ~38.5ºC) temperature were increased similarly during both trials (P&lt;0.01). The development of ExH and PaH resulted in a decrease in the 20:50 Hz force ratio, indicative of low‐frequency‐fatigue (P&lt;0.01). This alteration was more pronounced after ExH than PaH (P&lt;0.01). A rightward displacement in the force‐frequency relationship occurred after ExH and PaH (P&lt;0.05), but was exacerbated by ExH (P&lt;0.05). Peak twitch force decreased following ExH (P&lt;0.05) and was maintained after PaH. The exacerbated rightward shift in the force‐frequency relationship during ExH appears to stem from adjustments influencing force summation at low frequencies of stimulation. This is likely due to the development of peripheral fatigue, evidenced by a reduction in peak twitch force production.

Home-Based Functional Electrical Stimulation for Long-Term Denervated Human Muscle: History, Basics, Results and Perspectives of the Vienna Rehabilitation Strategy.

We will here discuss the following points related to Home-based Functional Electrical Stimulation (h-b FES) as treatment for patients with permanently denervated muscles in their legs: 1. Upper (UMN) and lower motor neuron (LMN) damage to the lower spinal cord; 2. Muscle atrophy/hypertrophy versus processes of degeneration, regeneration, and recovery; 3. Recovery of twitch- and tetanic-contractility by h-b FES; 4. Clinical effects of h-b FES using the protocol of the “Vienna School”; 5. Limitations and perspectives. Arguments in favor of using the Vienna protocol include: 1. Increased muscle size in both legs; 2. Improved tetanic force production after 3-5 months of percutaneous stimulation using long stimulus pulses (> 100 msec) of high amplitude (> 80 mAmp), tolerated only in patients with no pain sensibility; 3. Histological and electron microscopic evidence that two years of h-b FES return muscle fibers to a state typical of two weeks denervated muscles with respect to atrophy, disrupted myofibrillar structure, and disorganized Excitation-Contraction Coupling (E-CC) structures; 4. The excitability never recovers to that typical of normal or reinnervated muscles where pulses less than 1 msec in duration and 25 mAmp in intensity excite axons and thereby muscle fibres. It is important to motivate these patients for chronic stimulation throughout life, preferably standing up against the load of the body weight rather than sitting. Only younger and low weight patients can expect to be able to stand-up and do some steps more or less independently. Some patients like to maintain the h-b FES training for decades. Limitations of the procedure are obvious, in part related to the use of multiple, large surface electrodes and the amount of time patients are willing to use for such muscle training.

Home-based Functional Electrical Stimulation for long-term denervated human muscle: History, basics, results and perspectives of the Vienna Rehabilitation Strategy

We will here discuss the following points related to Home-based Functional Electrical Stimulation (h-b FES) as treatment for patients with permanently denervated muscles in their legs: 1. Upper (UMN) and lower motor neuron (LMN) damage to the lower spinal cord; 2. Muscle atrophy/hypertrophy versus processes of degeneration, regeneration, and recovery; 3. Recovery of twitch- and tetanic-contractility by h-b FES; 4. Clinical effects of h-b FES using the protocol of the “Vienna School”; 5. Limitations and perspectives. Arguments in favor of using the Vienna protocol include: 1. Increased muscle size in both legs; 2. Improved tetanic force production after 3-5 months of percutaneous stimulation using long stimulus pulses (&gt; 100 msec) of high amplitude (&gt; 80 mAmp), tolerated only in patients with no pain sensibility; 3. Histological and electron microscopic evidence that two years of h-b FES return muscle fibers to a state typical of two weeks denervated muscles with respect to atrophy, disrupted myofibrillar structure, and disorganized Excitation-Contraction Coupling (E-CC) structures; 4. The excitability never recovers to that typical of normal or reinnervated muscles where pulses less than 1 msec in duration and 25 mAmp in intensity excite axons and thereby muscle fibres. It is important to motivate these patients for chronic stimulation throughout life, preferably standing up against the load of the body weight rather than sitting. Only younger and low weight patients can expect to be able to stand-up and do some steps more or less independently. Some patients like to maintain the h-b FES training for decades. Limitations of the procedure are obvious, in part related to the use of multiple, large surface electrodes and the amount of time patients are willing to use for such muscle training.

Prevention of Percutaneous Spinal Cord Stimulation Electrode Migration: A 15-Year Experience

Percutaneous spinal cord stimulation electrodes have a propensity to migrate longitudinally, which is a costly complication that often compromises therapeutic effect. After implementing simple changes to our percutaneous electrode anchoring technique, we no longer encounter this migration. The current retrospective study updates previously reported results. We retrospectively examined data in a consecutive series of patients in whom we had secured a new percutaneous electrode by injecting < 0.1 cm(3) of adhesive into the silicone elastomer lead anchor. From 1998 through 2006, we used whichever anchor was supplied with each lead until we observed one case of migration through a short anchor; thereafter, we used a long, tapered anchor exclusively. From 2007 through 2013, we further modified our technique by adding a fascial incision to accommodate the tip of the anchor and by increasing the strength of our suture material. In the first series of 291 patients, followed through July 2007 (mean 4.75 years, range 1.1-9.0 years), 4 (1.37%) experienced electrode migration requiring surgical revision. Only one lead had moved with respect to its anchor; the other three anchors remained securely bonded to their leads. No migration (0.00%) occurred in the second series of 142 patients, followed through 2013 (mean follow-up 2.86 years, range 0.10-5.45 years). Improvements to our simple, inexpensive technique apparently have eliminated the most common complication of spinal cord stimulation.

Urologic Agents for Treatment of Bladder Dysfunction in Neurologic Disease

Bladder dysfunction, which is commonly associated with neurologic disorders, can present in myriad ways, from complete retention of urine to total urinary incontinence. The multiple options for treating neurogenic bladder dysfunction range from minimally invasive lifestyle changes to major surgical interventions. Interventions may be driven by patient-reported nuisance or by medical necessity, as in the case of impaired compliance with associated upper urinary tract compromise. Pharmacologic treatment has long been the mainstay in the management of bladder dysfunction, particularly for overactive bladder symptoms [1]. While there are many different medications for overactive bladder dysfunction, most are in the category of antimuscarinics. Each medication has a slightly different side effect profile, which may be important in the drug selection process [2]. When these are not tolerated or are ineffective, beta agonists, phosphodiesterase inhibitors, tricyclic antidepressants, and the gamma aminobutyric acid (GABA)-B agonist baclofen can be added or substituted. For difficulty emptying, alpha adrenergic antagonists can be used [3]. Intravesical options are also available for overactive bladder (OAB) symptoms. The most common is botulinum toxin, which works by decreasing the activity of the detrusor smooth muscle, thereby decreasing OAB symptoms [4]. Percutaneous nerve stimulation may also be used [5•].

Epidural Hematomas After Removal of Percutaneous Spinal Cord Stimulator Trial Leads

We report 2 cases of spinal epidural hematoma formation after the removal of percutaneous spinal cord stimulator trial leads and discuss the possible etiologies of these complications. Two patients developed spinal epidural hematomas shortly after removal of their percutaneous trial leads and required multilevel laminectomies for evacuation of the hematoma. Patient 1 reported taking aspirin the morning that his leads were pulled, whereas patient 2 had not taken aspirin in the 7 days before commencing his trial. There were 2 days between identification and evacuation of patient 1's hematoma, and he did not fully recover from the injury to his spinal cord. Patient 2 underwent surgery immediately with complete resolution of his symptoms. Currently, the neuromodulation community ascribes to the American Society of Regional Anesthesia and Pain Medicine guidelines, which state that nonsteroidal anti-inflammatory drugs do not significantly increase the risk for epidural hematoma with neuraxial anesthesia and, therefore, there is no need to discontinue these drugs before epidural or spinal anesthesia. We suggest that these guidelines may not be appropriate for neuromodulatory techniques that likely subject the surrounding vasculature to more trauma than neuraxial anesthesia. We recommend discontinuing nonsteroidal anti-inflammatory drugs, particularly aspirin, before neuromodulation procedures. Further investigation will establish a timeframe for holding these drugs to optimize patient safety.

The effect of repetitive bilateral arm training with rhythmic auditory cueing on motor performance and central motor changes in patients with chronic stroke

The aim of this study was to compare the effects of bilateral arm training with auditory cueing (BATRAC) versus control intervention on motor performance of the upper extremity (UE) and to explore the central neurophysiological mechanism underlying this effect in moderately impaired chronic stroke patients. This was a randomized-controlled clinical trial. Overall, 76 chronic stroke patients (mean age = 50.2 ± 6.2 years), 6–67 months after the onset of the first stroke were enrolled. They received either BATRAC (with both UE trained simultaneously in symmetric and asymmetric patterns) or control intervention (unilateral therapeutic exercises for the paretic UE). Each session lasted for 1 h, scheduled as three sessions/week (on an alternate day) for 8 successive weeks. Outcome measures included the Fugl-Meyer motor performance test for the UE (FMUE) and percutaneous transcranial magnetic stimulation to elicit motor-evoked potential (MEP) in paretic abductor pollicis brevis muscle. Group comparisons indicated a significantly better improvement in the MEP parameters (transcranial magnetic stimulation threshold, central motor conduction time, and MEP amplitude) in the BATRAC group. The FMUE scores increased in both groups, but there was no significant difference between groups in the FMUE scores. These findings recommend the use of BATRAC in chronic stroke patients not only to improve motor performance but also to induce central neurophysiological effects.

Spinal Epidural Hematoma After Spinal Cord Stimulator Trial Lead Placement in a Patient Taking Aspirin

Spinal epidural hematoma is a rare, but potentially devastating, consequence of accessing the epidural space for anesthesia or interventional pain procedures. There is no consensus to stop aspirin therapy before interventional chronic pain procedures. A 73-year-old woman with postlaminectomy pain syndrome and lumbar radiculopathy underwent percutaneous spinal cord stimulator lead placement. She had been taking aspirin 81 mg/d for several years. Twenty-four hours later, she developed an epidural hematoma. Prompt recognition and surgical management resulted in no long-term neurological sequelae. The only variable that could have led to our patient's epidural hematoma is aspirin. This is the first reported case of aspirin leading to an epidural hematoma following an interventional chronic pain procedure. Prior to interventional pain procedures, one should contemplate cessation of aspirin therapy because there are, at present, no consensus guidelines to direct such a decision.

This Month in Adult Urology

No AccessJournal of UrologyThis Month in Adult Urology1 Mar 2014This Month in Adult Urology William D. Steers William D. SteersWilliam D. Steers More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2013.12.016AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "This Month in Adult Urology." The Journal of Urology, 191(3), pp. 571–572 References 1 : The impact of repeat biopsies on infectious complications in men with prostate cancer on active surveillance. J Urol2014; 191: 660. Link, Google Scholar 2 : Efficacy and safety of the coadministration of tadalafil once daily with finasteride for 6 months in men with lower urinary tract symptoms and prostatic enlargement secondary to benign prostatic hyperplasia. J Urol2014; 191: 727. Link, Google Scholar 3 : Inflammatory and tissue remodeling urinary biomarkers before and after mid urethral sling surgery for stress urinary incontinence. J Urol2014; 191: 703. Link, Google Scholar 4 : Effect of repeated prostate biopsies on erectile function in men on active surveillance for prostate cancer. J Urol2014; 191: 744. Link, Google Scholar 5 : Prediction of early and late complications after oral mucosal graft harvesting: multivariable analysis from a cohort of 553 consecutive patients. J Urol2014; 191: 688. Link, Google Scholar 6 : Maintenance percutaneous posterior nerve stimulation for refractory lower urinary tract symptoms in patients with multiple sclerosis: an open label, multicenter, prospective study. J Urol2014; 191: 697. Link, Google Scholar © 2014 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 191Issue 3March 2014Page: 571-572 Advertisement Copyright & Permissions© 2014 by American Urological Association Education and Research, Inc.MetricsAuthor Information William D. Steers More articles by this author Expand All Advertisement PDF DownloadLoading ...

Effects of Pulse Current on Endurance Exercise and Its Anti-Fatigue Properties in the Hepatic Tissue of Trained Rats

Fatigue is synonymous with a wide spectrum of familiar physiological conditions, from pathology and general health, to sport and physical exercise. Strenuous, prolonged exercise training causes fatigue. Although several studies have investigated the effects of electrical stimulation frequency on muscle fatigue, the effects of percutaneous pulse current stimulation on fatigue in the hepatic tissue of trained rats is still unclear. In order to find an effective strategy to prevent fatigue or enhance recovery, the effects of pulse current on endurance exercise and its anti-fatigue properties in exercised rats were studied. Rats were subjected to one, three or five weeks of swimming exercise training. After exercise training, rats in the treated group received daily applications of pulse current. All rats were sacrificed after one, three or five weeks of swimming exercise, and the major biochemical indexes were measured in serum and liver. The results demonstrate that pulse current could prolong the exhaustion swimming time, as well as decrease serum ALT, AST and LD levels and liver MDA content. It also elevated serum LDH activity, liver SOD activity and glycogen content. Furthermore, pulse current increased the expression of Bcl-2 and decreased the expression of Bax. Taken together, these results show that pulse current can elevate endurance capacity and facilitate recovery from fatigue.

Maintenance Percutaneous Posterior Nerve Stimulation for Refractory Lower Urinary Tract Symptoms in Patients with Multiple Sclerosis: An Open Label, Multicenter, Prospective Study

Percutaneous tibial nerve stimulation is an effective second line therapy for lower urinary tract symptoms. Data on percutaneous tibial nerve stimulation maintenance treatment are scarce. In this study we evaluate its effectiveness and propose an algorithm of percutaneous tibial nerve stimulation maintenance treatment in patients with multiple sclerosis. In this prospective, multicenter, open label trial consecutive patients with multiple sclerosis and lower urinary tract symptoms unresponsive to medical therapy were treated with 12 weekly sessions of percutaneous tibial nerve stimulation. Responder patients (50% or greater improvement of lower urinary tract symptoms as measured by the patient perception of bladder condition questionnaire) entered a maintenance phase with individualized treatment frequency based on patient response. Lower urinary tract symptoms were assessed using a 3-day frequency volume chart, urodynamics and patient perception of bladder condition questionnaire. Treatment satisfaction was evaluated using a global response assessment scale and a treatment satisfaction visual analog scale. A total of 83 patients were included in the study and 74 (89%) responded to initial treatment. Persistent efficacy occurred in all initial responders after a mean treatment of 24 months. The greatest frequency of maintenance percutaneous tibial nerve stimulation was every 2 weeks. Lower urinary tract symptoms and patient treatment satisfaction improved with time compared to initial treatment (p <0.05). Bladder diary parameters and voiding parameters improved compared to baseline (p <0.05). Prolonged percutaneous tibial nerve stimulation treatment leads to a persistent improvement of lower urinary tract symptoms in patients with multiple sclerosis.

Neuroestimulación percutánea del nervio tibial posterior frente a neuroestimulación de B 6 (Sanyinjiao) en incontinencia urinaria de urgencia

ObjectiveComparison of effectiveness between electroacupuncture of SP 6 (Sanyinjiao) and percutaneous stimulation of the posterior tibial nerve. DesignProspective, blind randomized two-arm controlled pilot study. LocationPelvic Floor Unit, part of the Rehabilitation Interlevel Clinical Management Unit at the Hospital Universitario Reina Sofía (Córdoba, Spain). ParticipantsConsecutive sampling of 24 patients with urge incontinence that satisfied inclusion criteria, under the age of 75, with mild-severe involvement according to the International Consultation on Incontinence Questionnaire (ICIQ-SF) and the Bladder Control Self-Assessment Questionnaire (B-SAQ) and who have undergone conservative treatment for over 1 year, with a good level of collaboration. InterventionsElectrostimulation of SP 6 (Sanyinjiao) to one of the arms of the study, and percuta neous tibial nerve stimulation to the other, both subject to a total of 12 weekly sessions. Main outcome variablesVoiding frequency (diurnal and nocturnal), urge and leaking episodes, B-SAQ and ICIQ-SF results before and after treatment. ResultsA clinical and statistically significant improvement was visible in all outcome variables with both treatments. Results of percutaneous tibial nerve stimulation were superior to those of electroacupuncture of SP 6 for B-SAQ. No significant differences were found for the rest of variables. ConclusionsBoth percutaneous tibial nerve stimulation and electroacupuncture of SP 6 (Sanyinjiao) improve urge incontinence. Results are slightly better with percutaneous tibial nerve stimulation, without statistical significance, where neurostimulation ranks higher than electroacupuncture.

Avaliação da adição do tramadol sobre o tempo de regressão do bloqueio motor induzido pela lidocaína: estudo experimental em ratos

JUSTIFICATIVA E OBJETIVOS: O tramadol bloqueia potenciais somatossensitivos in vitro e pode ser associado a anestésicos locais com o intuito de melhorar a qualidade da analgesia. O objetivo deste estudo foi avaliar se o tramadol altera o tempo de regressão do bloqueio motor da lidocaína em duas diferentes concentrações. MÉTODO: Ratos machos da linhagem Wistar, pesando de 250 a 300 g, foram submetidos a bloqueio de nervo ciático guiado por neuroestimulação percutânea. Os animais foram distribuídos em quatro grupos (n = 5 por grupo): lidocaína a 2% (GI), lidocaína a 0,5% (GII), lidocaína a 2% / tramadol 1,25 mg (GIII), e lidocaína a 0,5% / tramadol 1,25 mg (GIV). Foram avaliados tempo de regressão parcial e tempo de regressão completa do bloqueio motor. RESULTADOS: Todos os animais apresentavam bloqueio motor completo no momento do despertar da anestesia, que regrediu completamente durante o período de observação. O tempo de regressão completa do efeito da lidocaína a 2% foi 41 ± 1,71 minutos, lidocaína a 0,5% foi 25,26 ± 0,83 minutos, lidocaína a 2% / tramadol foi 46,06 ± 0,88 minutos e lidocaína a 0,5% / tramadol foi 36,15 ± 1,18 minutos. A associação da lidocaína a 0,5% ao tramadol 1,25 mg foi mais eficaz que lidocaína a 0,5% isoladamente. Os dados são apresentados como média ± erro padrão da média (epm). Considerou-se significativo p < 0,05 usando a ANOVA seguido do teste de Tukey. CONCLUSÃO: Tramadol possui efeitos semelhantes a anestésicos locais e, quando usado como adjuvante da lidocaína, prolonga a duração do bloqueio motor em ratos.

Evaluation of a New Powerful Bone-Anchored Hearing System: A Comparison Study

The recent introduction of digital hearing aid technology for bone-conduction devices employing percutaneous stimulation may be beneficial for patients with conductive and mixed hearing loss and single sided deafness. Performance of a recently released sound processor for bone-anchored implants, the Ponto Pro Power from Oticon Medical (bone-conduction device 2 [BCD2]), was compared with that of the Baha Intenso from Cochlear (bone-conduction device 1 [BCD1]). Direct comparison of the subject's own device (BCD1) with the new device (BCD2) was examined in a nonrandomized design. Subjects were initially tested with BCD1. BCD2 was tested after a 4 wk acclimatization period. Eighteen subjects with mixed hearing loss and with at least 4 mo experience with BCD1 completed the study. Mean air-conduction and bone-conduction thresholds averaged across the frequencies of 500, 1000, 2000, and 4000 Hz were 73.9 and 34.2 dB HL, respectively. Performance of the two devices was evaluated objectively by measuring aided free-field thresholds, speech perception in quiet, and speech perception in noise. A subjective evaluation was carried out with the Abbreviated Profile of Hearing Aid Benefit (APHAB) (Cox and Alexander, 1995) and the Speech, Spatial and Qualities of Hearing Scale (SSQ) questionnaire (Gatehouse and Noble, 2004). In addition, user experiences, user satisfaction, and device preference were obtained via proprietary questionnaires. Statistical significance was established with analysis-of-variance (ANOVA) and paired t-statistics with Bonferroni correction. Aided free-field thresholds and speech reception thresholds (SRTs) in quiet were not statistically significantly different for either device (p > 0.05). In contrast, SRTs in noise were 2.0 dB lower (p < 0.001) for BCD2 than for BCD1. APHAB questionnaire scores on all subscales provided statistically significantly greater benefit (p < 0.05) for BCD2 than for BCD1. Also, with the SSQ most items in the speech and sound quality domain were significantly more favorable (p < 0.05) for BCD2 than for BCD1. Finally, all subjects preferred BCD2 over BCD1 with 14 subjects reporting a strong preference and four subjects an average preference for the digital signal processing provided by BCD2 over previous technology provided by BCD1.

Percutaneous Nerve Stimulation in Chronic Neuropathic Pain Patients due to Spinal Cord Injury: A Pilot Study

The long-term prognosis for neuropathic pain resolution following spinal cord injury (SCI) is often poor. In many SCI patients, neuropathic pain continues or even worsens over time. Thus, new treatment approaches are needed. We conducted a pilot study to evaluate the feasibility and effect of percutaneous (electrical) nerve stimulation (P(E)NS) in SCI patients with chronic neuropathic pain. In 18 weeks, 12 P(E)NS treatments were scheduled. Assessment with questionnaires was performed at baseline (T0), after 8 weeks (T8), 18 weeks (T18), and 12 weeks post-treatment (T30). From 26 screened patients, 17 were included. In total, 91.2% questionnaires were returned, 2 patients dropped out, and 4.2% of the patients reported minor side effects. Pain scores on the week pain diary measured with the numerical rating scale improved significantly at T8, from 6.5 at baseline to 5.4, and were still significantly improved at T18. Pain reduction of ≥ 30% directly after a session was reported in 64.6% sessions. In total, 6 patients experienced reduction in size of the pain areas at T18 and T30, with a mean reduction of 45.8% at T18 and 45.3% at T30. P(E)NS is feasible as an intervention in SCI patients and might have a positive effect on pain reduction in a part of this patient group.

Sacral neuromodulation for fecal incontinence and “low anterior resection syndrome” following neoadjuvant therapy for rectal cancer

It was the aim of this prospective study to analyze both feasibility and effectiveness of sacral neuromodulation for fecal incontinence and "low anterior resection syndrome" following neoadjuvant therapy for rectal cancer. All patients who underwent sacral neuromdulation following neoadjuvant therapy for rectal cancer (preoperative radiochemotherapy, oncologic rectal resection with total mesorectal excision) were prospectively enrolled in the study. Only patients with failure of conservative treatment and without any evidence of residual or recurrent tumor disease were candidates for sacral neuromdulation which was performed by a two-stage procedure (diagnostic percutaneous test stimulation followed by definite implant). In addition to feasibility, primary end points included success (reduction of incontinent episodes), continence and defecation status (assessed by Cleveland Clinic Incontinence Score and Altomare score), and quality of life (EQ-5D). Anal manometry was performed preoperative and at 12-month follow-up. Follow-up information was derived from clinical examination 3, 6, and 12 months postoperatively. Nine patients (three females, six males) with a mean age of 61 years underwent sacral neuromodulation following neoadjuvant therapy for rectal cancer. Implantation rate was 100 %. No septic morbidity was observed. After a mean follow-up of 12 months, mean Cleveland Clinic Incontinence Score was reduced from 18.2 to 6.0 (p < 0.01). Incontinence episodes were significantly reduced from 7 to 0.5 (per day) and 20 to 8 (per week). Fecal urgency, fragmented defecation, and soiling were improved or resolved in two thirds. Altomare score was significantly reduced from 21.0 to 9.3 (p < 0.01). Anorectal manometry did not correlate with clinical success. Quality of life was significantly improved (EQ-5D generic: 0.42 vs. 0.74, EQ-5D-VAS score: 20 vs. 90, p < 0.01). Preliminary results of sacral neuromodulation in patients with fecal incontinence and symptoms of "low anterior resection syndrome" are promising and enrich the therapeutic modalities if conservative management has failed.

Spinal Cord Stimulation for Radicular Pain Following Retained Bullet in the Spinal Canal

We are reporting on the implantation of a spinal cord stimulator to treat intractable radicular pain following a retained bullet fragment in the spinal canal. Such retained fragments are associated with risks including pain, neurological deficit, infection, toxic effects, and migration. Our patient was a young man with radicular pain and history of a gunshot entering the abdomen. Computed tomography of the spine had revealed a nearly complete bullet in the right paracentral canal at L4, partially extending into the lateral recess. He presented 17 months after his injury with gradually worsening pain and parasthesias radiating from the back to the whole right leg and foot. There was no weakness. As the patient had failed conservative therapy, procedural options were considered. In this case, the potential benefits of epidural steroid injection by any approach might not have outweighed risks of infection, related to foreign body and local steroid, or possible migration due to mechanical forces during injection. As he may well need repeated epidural steroid injections to manage his pain, this increases his risk for infection. A percutaneous trial spinal cord stimulation lead was placed, with epidural entry well away from the bullet. After good results, a permanent system was implanted. There was no evidence of infection or migration, and excellent pain relief was achieved. Bullets and other foreign bodies retained in the spinal canal can cause progressive neurologic symptoms through reactive tissue formation and compression. Spinal cord stimulation can relieve radicular pain while avoiding risks associated with altering the location of the offending foreign body. Key words: Spinal cord stimulation, radicular pain, retained bullet, gunshot wound, spinal canal, spinal injury, lumbar spine

Challenges and Opportunities in Restoring Function After Paralysis

Neurotechnology has made major advances in development of interfaces to the nervous system that restore function in paralytic disorders. These advances enable both restoration of voluntary function and activation of paralyzed muscles to reanimate movement. The technologies used in each case are different, with external surface stimulation or percutaneous stimulation generally used for restoration of voluntary function, and implanted stimulators generally used for neuroprosthetic restoration. The opportunity to restore function through neuroplasticity has demonstrated significant advances in cases where there are retained neural circuits after the injury, such as spinal cord injury and stroke. In cases where there is a complete loss of voluntary neural control, neural prostheses have demonstrated the capacity to restore movement, control of the bladder and bowel, and respiration and cough. The focus of most clinical studies has been primarily toward activation of paralyzed nerves, but advances in inhibition of neural activity provide additional means of addressing the paralytic complications of pain and spasticity, and these techniques are now reaching the clinic. Future clinical advances necessitate having a better understanding of the underlying mechanisms, and having more precise neural interfaces that will ultimately allow individual nerve fibers or groups of nerve fibers to be controlled with specificity and reliability. While electrical currents have been the primary means of interfacing to the nervous system to date, optical and magnetic techniques under development are beginning to reach the clinic, and provide great opportunity. Ultimately, techniques that combine approaches are likely to be the most effective means for restoring function, for example combining regeneration and neural plasticity to maximize voluntary activity, combined with neural prostheses to augment the voluntary activity to functional levels of performance. It is a substantial challenge to bring any of these techniques through clinical trials, but as each of the individual techniques is sufficiently developed to reach the clinic, these present great opportunities for enabling patients with paralytic disorders to achieve substantial independence and restore their quality of life.