Electrical Stimulation for Hemiplegic Shoulder Pain

Study Overview
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Brief Summary
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Post-stroke shoulder pain is a major rehabilitation problem affecting moderate to severely impaired stroke survivors. Surface electrical stimulation (ES) of muscles surrounding the hemiparetic shoulder has been demonstrated to be beneficial, but despite the evidence for therapeutic benefit, the clinical implementation of surface ES for poststroke shoulder pain has been difficult. In order to address the limitations of surface ES, the investigative team pioneered the development of percutaneous intramuscular (IM) ES for the treatment of post-stroke shoulder pain. However, prior to acceptance by the clinical community, additional gaps in the scientific and clinical knowledge need to be addressed. This study begins to do so. The primary objective is to estimate the relative pain reduction associated with IM ES vs. usual care. We hypothesize that the IM ES group will exhibit a larger effect size with respect to pain reduction compared to usual care. A secondary objective is to estimate the effect on health related QOL of IM ES vs. usual care. Demonstration of improvement in QOL will validate the clinical relevance of the intervention. We hypothesize that the IM ES group will exhibit greater improvement in health related QOL compared to usual care.

Official Title
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Electrical Stimulation for Hemiplegic Shoulder Pain

Conditions
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Stroke, Shoulder Pain

Intervention / Treatment
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* Device: Intramuscular Electrical Stimulator
* Other: Outpatient Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: shoulder pain localized to the glenohumeral joint, subacromial area or deltoid insertion associated with any of the following conditions: a) rest; b) passive abduction or external rotation ROM; c) active abduction or external rotation ROM; or d) manual palpation weakness of shoulder abductors (≤4/5 on MRC if isolated movement is present) age ≥21-yrs time from stroke ≥ 3-mo shoulder pain onset after the most recent stroke duration of shoulder pain ≥ 3-mo severity of shoulder pain on BPI-SF 3 ≥4 cognitive ability to fulfill study requirements [a) exhibit 3 object immediate and 30 minute recall; b) ability to use a numeric rating scale (using a 0-10 numeric rating scale) by correctly ranking the tightness they feel on the unaffected arm of 3 low-pressure inflations with a standard sphygmomanometer cuff which follow a predetermined sequence (20, 40 and 0 mm Hg); and c) ability to follow 3-stage commands] availability of a reliable adult who can check the skin and assist the participant with the treatment protocol willing and able to report severity of shoulder pain throughout the study period willing to make all scheduled study visits post-implantation. Exclusion Criteria: evidence of joint or overlying skin infection insensate skin >1 opioid or nonopioid analgesics daily for shoulder pain daily intake of pain medications for any other chronic pain intra-articular or subacromial steroid injections to the shoulder in the previous 12-wks botulinum toxin injection to the trapezius, pectoralis or subscapularis muscle in the previous 12-wks receiving physical or occupational therapies for shoulder pain physician-diagnosed shoulder pathology symptomatic within the 5 yrs prior to CVA bleeding disorder INR>3.0 for those on warfarin [INR>3.0] poorly controlled diabetes [HbA1c>7.0] medical instability pregnancy uncontrolled seizures (>1/mo for 6-mo) uncompensated hemi-neglect severely impaired communication moderate to severe depression other confounding conditions such as ipsilateral upper limb lower motorneuron lesion, Parkinson's Disease, spinal cord injury, traumatic brain injury or multiple sclerosis other medical issues such as complex regional pain syndrome, bicipital tendonitis, myofacial pain syndrome, etc. the following cardiac conditions: a) history of arrhythmia with hemodynamic instability, such as ventricular tachycardia, supraventricular tachycardia and rapid ventricular response atrial fibrillation; b) any implantable stimulator such as demand pacemakers or defibrillators; and c) valvular heart disease including artificial valves (due to risk of infection and endocarditis) likely non-compliance factors such as distance from the center, inadequate social support, or psychiatric/psychologic factors

Ages Eligible for Study
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Minimum Age: 21 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: IM Electrical Stimulation (IM ES)<br>The IM ES Group will receive electrical stimulation treatment for three weeks (6 hrs daily) with an Intramuscular Electrical Stimulator following a one week electrode stabilization period. | Device: Intramuscular Electrical Stimulator<br>* A sterile percutaneous IM electrode is implanted in the shoulder using a 20-gauge hypodermic needle and connected to an external cable. The exit site and electrode are covered by a bandage, but the cable extends out. After a one week stabilization period, the cable is connected to a stimulator. A self-adhesive surface electrode serves as the indifferent electrode. Stimulation intensity is set by the investigator. The prescription for daily stimulation treatment will be 6 hrs. The duty cycle and daily dose will remain constant throughout the treatment, but stimulus parameters may be adjusted by the research staff as deemed appropriate. The treatment period will be 3 weeks, after which the electrode will be removed. Total time of electrode implantation is no more than 29 days.<br>|
| Active Comparator: Usual Care (UC)<br>The Usual Care Group will receive outpatient therapy for four weeks, coupled with prescribed daily home exercises. | Other: Outpatient Therapy<br>* Subjects will receive 8 hrs of outpatient therapy over a four week period from a treating therapist, coupled with prescribed daily home exercises. The therapist will implement an individualized treatment plan consistent with the needs of the participant.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Brief Pain Inventory Short Form | The BPI is a pain questionnaire, which assesses both pain intensity (sensory dimension) and the interference (reactive dimension) of pain in daily activities. Pain intensity is measured on a 0 - 10 scale, with 0 being no pain and 10 being worst possible. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ShoulderQ VGRS Scale | The ShoulderQ Visual Graphics Rating Scale (VGRS) T is a structured questionnaire designed to assess severity of HSP at rest during the day, on movement, and at night on a 0-30 scale where higher numbers indicate greater pain. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| SF-36 Bodily Pain Component | The SF-36v2 is a population-norm based health related quality of life measure, presented in T-scores where population average equals a score of 50 with a standard deviation of 10. Maximum is 100, with higher score indicating greater health realated quality of life. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Pain-free External ROM, Degrees | Passive pain-free Externa ROM is a motor recovery measure. The subject was supine with the shoulder adducted with hand resting on the abdomen, elbow flexed, and with the humerus supported by the mat. The axis of a universal goniometer was centered on the olecranon process of the ulna projecting through the humeral shaft toward the humeral head. The subject's shoulder was externally rotated passively to the pain threshold, defined as the start of any pain. Pain at rest was recorded as 0 degrees. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Fugl-Myer Motor Assessment (FMA) - Upper Extremity | The Fugl-Myer Motor Assessment (FMA) is a motor recovery measure. Volitional movement of the upper limb (shoulder, elbow, forearm, wrist, and hand) is examined in and out of synergies. Each item was graded on a 3-point ordinal scale and summed to provide a maximum score of 66, with higher scores indicating lower impairment. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Pain Interference Questionnaire | BPI-9 from Brief Pain Inventory, Short Form. Pain interference is on a 0 - 10 scale, with 0 being no interference, and 10 being complete interference. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Isometric Shoulder Abduction Moment, Ratio Affected to Unaffected | A measure of isometric strength in response to audio cue. Isometric shoulder abduction moment was measured with a Biodex Biomechanical Measurement System (Biodex Medical Systems, Shirley, NY). The average moment during the last second of the audible tone was calculated for each trial and those values were averaged over the three trials. Subjects underwent testing of both shoulders, non-paretic side first, and the results are presented as the ratio of the paretic shoulder to the non-paretic shoulder to decrease the influence of intra-subject variability between measurements. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Delay in Initiation of Shoulder Abduction EMG Activity | Electromyographic activity from the deltoid was also measured during the isometric abduction moment trials. Surface EMG recording electrodes (2 cm x 2 cm) were placed over the deltoid muscle and spaced approximately 4 cm apart. The EMG amplifier gain was adjusted to record as high-fidelity an EMG signal as possible during shoulder abduction. Delay of initiation (DOI) was defined as the duration between onset of the audibe tone and the onset of EMG signal. Raw EMG signals were analyzed visually to determine the earliest rise in EMG activity relative to steady state for delay of initiation. The mean DOI of the three trials were calculated, and the ratio of the paretic to non-paretic shoulder DOI were used as summary metrics. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 
| Delay in Termination of Shoulder Abduction EMG Activity | Electromyographic activity from the deltoid was also measured during the isometric abduction moment trials. Surface EMG recording electrodes (2 cm x 2 cm) were placed over the deltoid muscle and spaced approximately 4 cm apart. The EMG amplifier gain was adjusted to record as high-fidelity an EMG signal as possible during shoulder abduction. Delay of termination (DOT) was defined as the duration between cessation of the audible tone and return of the EMG signal to baseline. Raw EMG signals were analyzed visually to determine the earliest rise in EMG activity relative to steady state for delay of initiation, and return to steady for delay of termination. The mean DOT of the three trials were calculated, and the ratio of the paretic to non-paretic shoulder DOT were used as summary metrics. | Baseline (Week 0); Start of Treatment (Week 1); End of Treatment (EOT, Week 4); EOT + 6 wks (Week 10); EOT + 12 wks (Week 16) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Stroke, Shoulder pain, Electrical stimulation, Neuromuscular stimulation, Intramuscular stimulation