Efficacy of Functional Electrical Stimulation (FES) in Persons Receiving Botulinum Neurotoxin for Upper Extremity Spasticity

Single Blind, Randomized Study to Determine the Safety and the Efficacy of Using Functional Electrical Stimulation (FES) and Repetitive Task Practice vs. Repetitive Task Practice Alone in Persons Receiving Botulinum Neurotoxin Type A Injections for Upper Extremity Spasticity

FES is a form of treatment with a device to aid movement in people who have had damage to their brain or spinal cord. Small electrical impulses are used to excite/stimulate the nerves that supply paralyzed muscles. This activates those muscles, enabling them to produce basic but useful movement. Self-adhesive patches (electrodes) are placed on the skin close to the nerve that supplies the muscle and are connected by wires to a stimulator that produces the impulses. In this way, FES is used to correct the muscle weakness that is caused by injury to the brain or spinal cord.

Repetitive task practice is an "activity-based" therapy program that has been shown to enhance the recovery of hand and arm functions after stroke. This therapy consists of a set of training activities that are designed by a qualified therapist specific to your functional abilities that are to be performed with the impaired hand. These activities are designed to stimulate functional improvement with repetitive practice.

Spasticity is a nervous system disorder where certain muscles are continuously contracted. Botox injections are commonly used to help to reduce spasticity in areas of the body with increased muscle tone. This research is designed to look at any additional benefit that may occur when Botox injections are combined with specific occupational therapy exercises and with a device that uses functional electrical stimulation (FES) to help improve muscle function after stroke.

This is a single-blinded, randomized controlled trial examining the effect of repetitive task practice (RTP) and functional electrical stimulation (FES) in individuals who receive routine clinical Botox ® injections for upper extremity spasticity. Botox® injections in combination with repetitive task practice (RTP) is used routinely to manage upper limb spasticity after stroke or acquired brain injury. RTP is an activity-based rehabilitation program that has been shown effective in promoting motor recovery (Wolf et al., 2002), but it requires a sufficient level of baseline motor function. Since FES enhances motor function, we hypothesize that an FES-assisted RTP intervention will provide greater improvement in hand function than RTP alone in patients receiving Botox ® injections.

The primary outcome will be upper extremity use during activities of daily living assessed observationally by the motor activities log (MAL-O). Secondary outcomes will be 1) dexterous hand function as measured by the action research arm test (ARAT); 2) client's perception of self-performance in activities of daily living assessed with the (MAL - Self Report); 3) global upper extremity impairment assessed by the Chedoke-McMaster Assessment (CMA); and 4) clinical spasticity assessed by the Modified Ashworth Scale (MAS).

The primary endpoint will be 6 weeks post-injection. Outcomes will also be assessed at a secondary endpoint, 12 weeks post-injection, to determine the persistence of treatment effects.

Inclusion Criteria:

• Minimum 6 months post injury/insult with unilateral upper limb spasticity of the elbow, wrist and/or finger flexors.
• Preinjection Modified Ashworth scores > 2 in at least one of the following areas: elbow, wrist, or finger flexors.
• Subjects must meet criteria for CMA Hand Impairment Scale Stage 2 and be able to complete Task 3 (thumb to index finger) of the CMA Hand Impairment Scale Stage 3, or demonstrate 50% gross grasp to be included.
• Botulinum toxin A (Botox®) stable patients (have received at least two prior doses of the agent with first dose occurring at least 6 months prior to study enrollment).
• Able to answer reliably to yes/no questions.
• Able to follow reliably 1-step instructions.
• Written informed consent.
• Females enrolled in this study who are of childbearing age will be required to use adequate measures of birth control for the entire study period. Those who do not agree will be excluded.

Exclusion Criteria:

• Uncontrolled, clinically significant medical condition other than the condition under evaluation.
• Severe, fixed joint contracture in the affected arm. Patients with mild contracture that does not significantly impact function will be included based upon the assessment of the PI.
• Known allergy or sensitivity to any of the components in the study medication.
• Females who are pregnant, breast-feeding, or planning a pregnancy during the study or who think that they may be pregnant at the start of the study, or females of childbearing potential who are unable or unwilling to use a reliable form of contraception during the study.
• Concurrent participation in another investigational drug or device study or participation in the 30 days immediately prior to study enrollment.
• Treatment with botulinum toxin of any serotype for any reason in less than 3 months prior to initial date of injection for the study.
• Any medical condition that may put the subject at increased risk with exposure to botulinum toxin type A including diagnosed myasthenia gravis, Eaton-Lambert syndrome, amyotrophic lateral sclerosis, or any other disorder that might interfere with neuromuscular function.
• Evidence of recent alcohol or drug abuse.
• Infection or skin disorder at an anticipated injection and/or electrical stimulation sites.
• Any condition or situation that, in the investigator's opinion, may put the subject at significant risk, confound the study results, or interfere significantly with the subject's participation in the study.
• Use of aminoglycoside antibiotics, curare like agents, or other agents that might interfere with neuromuscular function.
• Individuals with a cardiac pacemaker, a defibrillator, or baclofen pump.
• Individuals with an unhealed or healing fracture or dislocation in the arm to be evaluated.