Fully implantable peripheral nerve stimulation for the treatment of hemiplegic shoulder pain: a case report.

This case report describes the first participant treated with a fully implantable, single-lead peripheral nerve stimulation system for refractory hemiplegic shoulder pain. During the 6-wk trial stage, a temporary lead was placed percutaneously near the terminal branches of the axillary nerve to the deltoid. The primary outcome measure was the Brief Pain Inventory-Short Form Question 3, a 0-10 pain numeric rating scale. The participant experienced 75% pain reduction and proceeded to the implantation stage, where he received a single-lead, implantable pulse generator. After 3 wks, the participant became pain-free. However, 7 wks after implantation, the system was turned off because of an unrelated acute medical illness. Hemiplegic shoulder pain reemerged with a Brief Pain Inventory-Short Form Question 3 score of 9. After 11 wks of recovery, peripheral nerve stimulation was reinitiated and the participant became pain-free through the 9-mo follow-up. At 12 mos, Brief Pain Inventory-Short Form Question 3 score was 1. This case report demonstrates the feasibility of a single-lead, fully implantable peripheral nerve stimulation system for refractory hemiplegic shoulder pain.

Treatment of post-amputation pain with peripheral nerve stimulation.

BACKGROUND: Present treatment methods are often unsatisfactory in reducing post-amputation pain. Peripheral nerve stimulation (PNS) could reduce the pain, but it is rarely used because present methods require invasive surgical access and precise placement of the leads in close proximity (≤ 2 mm) with the nerve. METHODS: The present study investigated the feasibility of delivering PNS to patients with moderate-to-severe post-amputation pain in the lower extremity using a fine-wire lead placed percutaneously under ultrasound guidance a remote distance (0.5-3.0 cm) away from the sciatic and/or femoral nerves. RESULTS: Fourteen of the 16 subjects who completed in-clinic testing responded to stimulation, reported ≥ 75% paresthesia coverage, obtained clinically significant pain relief, and proceeded to a two-week home trial with a percutaneous PNS system. Two of the 14 responders had their leads removed early because of accidental dislodgement (N = 2), two had temporary discomfort near the lead (N = 2), and one had return of post-amputation pain despite stimulation (N = 1) and did not complete the home trial. The nine responders who completed the home trial reported reductions in their mean daily worst post-amputation pain (56 ± 26%, 56 ± 26%, N = 9), average residual limb pain (72 ± 28%, 42 ± 27%, N = 7), average phantom limb pain (81 ± 28%, 47 ± 48%, N = 7), residual limb pain interference (81 ± 27%, 53 ± 17%, N = 6), phantom limb pain interference (83 ± 31%, 56 ± 46%, N = 7), and Pain Disability Index (70 ± 38%, 55 ± 32%, N = 9) during the second week of stimulation and four weeks after the end of stimulation, respectively. All nine responders rated their change in quality of life as improved at the end of stimulation and at the end of the four-week follow-up period. Subjects reported minor decreases in the Beck Depression Inventory scores (43 ± 51%, 32 ± 57%, N = 9). Most subjects had no substantial changes other than minor decreases (N = 3) in pain medication. CONCLUSION: Achievement of significant pain relief and improvements in quality of life with a minimally invasive method of PNS holds promise for providing relief of post-amputation pain.

Electrical stimulation of the urethra evokes bladder contractions and emptying in spinal cord injury men: case studies.

OBJECTIVE: Electrical stimulation of the urethra can evoke bladder contractions in persons with spinal cord injury (SCI). The objective of this study was to determine whether electrical stimulation of the urethra could evoke bladder contractions that empty the bladder. METHODS: The first patient was a 45-year-old man with a T6 ASIA A SCI secondary to a gunshot wound 15 years prior. The second patient was a 51-year-old man with a T2 ASIA A SCI secondary to a fall from scaffolding 2 years prior. Both patients demonstrated neurogenic detrusor overactivity on urodynamics and managed their bladder with clean intermittent catheterization and oxybutynin medication. Following informed consent, each patient discontinued oxybutynin 2 days prior to urodynamic testing. Urodynamics were performed with a custom 12 French balloon catheter mounted with ring-shaped electrodes (3 mm) positioned in the prostatic urethra. After filling the bladder to approximately three-fourth of capacity at a rate of 25 ml/minute, the urethra was stimulated with a range of parameters to determine whether electrical stimulation could evoke a bladder contraction and empty the bladder. RESULTS: Electrical stimulation of the prostatic urethra evoked bladder contractions (peak detrusor pressures of 60-80 cm H(2)O) that emptied the bladder in both subjects. In the first subject, stimulation (9-12 mA, 20 Hz) emptied 64-75%, leaving post-void residual volumes (PVRs) of 41-20 ml. In the second subject, stimulation (20 mA, 20 Hz) emptied 68-77%, leaving PVRs of 56-45 ml. CONCLUSION: Urethral stimulation evoked bladder emptying in persons with SCI.

Electrical stimulation of the urethra evokes bladder contractions in a woman with spinal cord injury.

OBJECTIVE: Electrical stimulation of pudendal urethral afferents generates coordinated micturition in animals and bladder contractions in men after spinal cord injury (SCI), but there is no evidence of an analogous excitatory urethra-spinal-bladder reflex in women. The objective of this study was to determine whether electrical stimulation of the urethra could evoke bladder contractions in a woman with SCI. CASE REPORT: A 38-year-old woman with a C6 ASIA A SCI who managed her bladder with clean intermittent catheterization and oxybutynin demonstrated neurogenic detrusor overactivity on urodynamics. Oxybutynin was discontinued 2 days prior to urodynamic testing with a custom 12F balloon catheter mounted with ring-shaped electrodes located in the bladder neck, mid urethra, and distal urethra. The inflated balloon was placed against the bladder neck to stabilize the catheter electrodes in place along the urethra. However, the balloon limited emptying during contractions. Urodynamics were performed at a filling rate of 25 mL/minute until a distention-evoked bladder contraction was observed. The urethra was stimulated over a range of bladder volumes and stimulus parameters to determine whether electrical stimulation could evoke a bladder contraction. FINDINGS: Electrical stimulation via urethral electrodes evoked bladder contractions that were dependent on bladder volume (>70% capacity) and the intensity of stimulation. CONCLUSIONS: This is the first report of an excitatory urethra-spinal-bladder reflex in a woman with SCI. Future studies will determine whether this reflex can produce bladder emptying.

Intramuscular electrical stimulation for hemiplegic shoulder pain: a 12-month follow-up of a multiple-center, randomized clinical trial.

OBJECTIVE: Assess the effectiveness of intramuscular electrical stimulation in reducing hemiplegic shoulder pain at 12 mos posttreatment. DESIGN: A total of 61 chronic stroke survivors with shoulder pain and subluxation participated in this multiple-center, single-blinded, randomized clinical trial. Treatment subjects received intramuscular electrical stimulation to the supraspinatus, posterior deltoid, middle deltoid, and upper trapezius for 6 hrs/day for 6 wks. Control subjects were treated with a cuff-type sling for 6 wks. Brief Pain Inventory question 12, an 11-point numeric rating scale was administered in a blinded manner at baseline, end of treatment, and at 3, 6, and 12 mos posttreatment. Treatment success was defined as a minimum 2-point reduction in Brief Pain Inventory question 12 at all posttreatment assessments. Secondary measures included pain-related quality of life (Brief Pain Inventory question 23), subluxation, motor impairment, range of motion, spasticity, and activity limitation. RESULTS: The electrical stimulation group exhibited a significantly higher success rate than controls (63% vs. 21%, P = 0.001). Repeated-measure analysis of variance revealed significant treatment effects on posttreatment Brief Pain Inventory question 12 (F = 21.2, P < 0.001) and Brief Pain Inventory question 23 (F = 8.3, P < 0.001). Treatment effects on other secondary measures were not significant. CONCLUSIONS: Intramuscular electrical stimulation reduces hemiplegic shoulder pain, and the effect is maintained for > or =12 mos posttreatment.

Intramuscular neuromuscular electric stimulation for poststroke shoulder pain: a multicenter randomized clinical trial.

OBJECTIVE: To assess the effectiveness of intramuscular neuromuscular electric stimulation (NMES) in reducing poststroke shoulder pain. DESIGN: Multicenter, single-blinded, randomized clinical trial. SETTING: Ambulatory centers of 7 academic rehabilitation centers in the United States. PARTICIPANTS: Volunteer sample of 61 chronic stroke survivors with shoulder pain and subluxation. INTERVENTION: Treatment subjects received intramuscular NMES to the supraspinatus, posterior deltoid, middle deltoid, and trapezius for 6 hours a day for 6 weeks. Control subjects were treated with a cuff-type sling for 6 weeks. Main outcome measure Brief Pain Inventory question 12 (BPI 12), an 11-point numeric rating scale administered in a blinded manner at the end of treatment, and at 3 and 6 months posttreatment. RESULTS: The NMES group exhibited significantly higher proportions of success based on the 3-point or more reduction in BPI 12 success criterion at the end of treatment (65.6% vs 24.1%, P<.01), at 3 months (59.4% vs 20.7%, P<.01), and at 6 months (59.4% vs 27.6%, P<.05). By using the most stringent "no pain" criterion, the NMES group also exhibited significantly higher proportions of success at the end of treatment (34.4% vs 3.4%, P<.01), at 3 months (34.4% vs 0.0%, P<.001), and at 6 months (34.4% vs 10.3%, P<.05). CONCLUSIONS: Intramuscular NMES reduces poststroke shoulder pain among those with shoulder subluxation and the effect is maintained for at least 6 months posttreatment.