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Eleven patients with chronic spastic hemiparesis were treated with biosignal processing (BSP), a modified biofeedback method in which the patient practices useful tasks, not isolated individual movements. A surface EMG measures sequential movements, and an acoustic signal monitors muscle exertion. The patient first learns how the signal develops by using the unaffected limb. Then the patient tries to reproduce the course of the signal in the paretic limb. Patients received 12 to 30 treatments for upper and/or lower extremities. We measured maximum strength as expressed through the EMG signal; ability to perform the trained action as measured by specific grading systems; and general increase in movement competence during a Bobath movement test. Ten patients showed improved strength; four made marked progress in the performance of specific tasks with the upper extremity, as did four with the lower extremity. Four patients in each group improved in general movement. We recommend the integration of useful tasks into movement exercises in EMG biofeedback therapy. 
Wissel J. Hosp. Am Urban, Berlin, Germany. Arch Phys Med Rehabilitation 

The purpose of this study was to evaluate the efficacy of the use of neuromuscular stimulation (NMS)-induced contraction of the paralyzed muscles to produce an active muscle pump for removing excess fluid and compare its effect with elevation of the upper extremity. The effects of 30 minutes of NMS of the finger and wrist flexors and extensors were compared with the effects of 30 minutes of limb elevation alone. Each of eight cerebrovascular accident (CVA) patients with visible hand edema received both treatments, one on each of 2 consecutive days. Measures of hand and arm volume and upper and lower arm girth were taken before and after each treatment. Analyses comparing mean percentage change scores for both treatments showed large and significant treatment effects for all dependent measures. The finding suggests that NMS was more effective for reduction of hand edema than limb elevation alone for this sample of eight CVA patients. 
Faghri PD. University of Connecticut, USA. Journal Hand Therapy 

Background and Purpose: Overcoming chronic hemiparesis from a cerebrovascular accident (CVA) can be challenging for many patiens, especially after the first 12 months after the CVA. With the use of established motor control theories, the present study investigated electromyogram (EMG)-triggered neuromuscular stimulation and bilateral coordination training. Methods: Twenty-five CVA subjects volunteered to participate in this motor recovery protocol study. Subjects were randomly assigned to 1 of 3 groups: (1) coupled protocol of EMG-triggered stimulation and bilateral movement (n=10); (2) EMG-triggered stimulation and unilateral movement (n=10); or (3) control (n=5). all participants completed 6 hours of rehabilitation during a 2-week period according to group assignments. Motor capabilities of the wrist and fingers were evaluated on the basis of 3 categories of motor tasks in a pretest - posttest control group design. Results: Significant findings for the (1) number of blocks moved in a functional task, (2) chronometric reaction times to initiate movements, and (3) sustained muscle contraction capability all favored the coupled bilateral movement training and EMG-triggered neuromuscular stimulation protocol group. In addition, the unilateral movement/stimulation group exceeded the control group in the number of blocks moved and rapid onset of muscle contractions. Conclusions: This new evidence is convincing in that subjects in the coupled protocol group were able to demonstrate enhanced voluntary motor control across 3 categories of tasks. Chronic hemiparesis decreased considerably in the wrist and fingers as CVA patients expanded their motor repertoire. 
Cauraugh J.H. Journal: Stroke 

Purpose: The aims of this project are to assess the efficacy of EMG-controlled neuromuscular stimulation in enhancing the upper-extremity motor recovery of chronic stroke survivors, and to determine whether EMG-controlled neuromuscular stimulation mediates its effect on motor recovery via central mechanisms. Methodology: Phase I of the study will identify neurophysiologic measures of brain function that correlate with objective measures of motor impairment. Chronic stroke survivors will be evaluated with objective measures of motor impairment (active range of motion, joint torques, Fugl-Meyer Motor Assessment, and EMG initiation and termination characteristics) and neurophysiologic measures of central motor function (Single Photon Emission Computed Tomography, Transcortical Magnetic Stimulation and Somatosensory Evoked Potentials). Phase II will consist of a single-blinded, randomized clinical trial to assess the effects of EMG-controlled neuromuscular stimulation on objective measures of motor impairment and measures of central motor function identified in phase I. Progress: A total of 20 chronic stroke survivors will be enrolled in phase I over a 2-year period, and 34 chronic stroke survivors in phase II over a 3-year period. Implications: This study will demonstrate that EMG-controlled neuromuscular stimulation enhances the motor recovery of chronic stroke survivors, and that the motor recovery is mediated by central mechanisms. The proposed intervention may be effective for acute stroke survivors and persons with other forms of cerebral motor dysfunction such as traumatic brain injury, cerebral palsy and multiple sclerosis. EMG-controlled neuromuscular stimulation may also be effective for lower limb motor recovery. Finally, techniques developed for assessing central motor function may be useful for evaluating other interventions directed at stroke rehabilitation. 
John Chae MD Center for Physical Medicine and Rehabilitation University of Cleveland, USA 

Purpose: The general purpose of this project is to develop a device for facilitating motor relearning for stroke survivors. The device will detect weak electromyographic (EMG) signals generated by a paretic muscle and consequently deliver stimulation currents to the same muscle to result in its strong contraction. The device will consist of a set of electrodes for sensing and stimulation and electronic circuitry for signal processing and stimulus generation. Methodology: During Phase I, we shall pursue the following objectives to produce and assess a pre-prototype device: first, we shall develop a tripolar intramuscular electrode that is suitable for both EMG sensing and muscle stimulation. The electrode should have a diameter small enough to be loaded into a 19-gauge hypodermic needle for percutaneous implantation. It should be durable enough to withstand muscle contraction without breakage for at least 4 weeks, and sufficiently flexible and include an anchoring mechanism capable of maintaining the intended position for the same period. Then we shall develop electronic circuits that, when connected to the tripolar intramuscular electrode, can reliably detect EMG signals and deliver stimulation pulses to the target muscle. The detecting circuitry should be able to detect very weak EMG signals, in the order of 1 V in a paretic muscle, while having high immunity to the very strong stimulation artifact generated by the stimulus current. The stimulation circuitry should be able to generate charge-balanced, current-regulated, biphasic pulses for safe and effective intramuscular stimulation. Finally, we shall evaluate the performance of the sensing-stimulation system in three stroke survivors. The implantation of the intramuscular electrode should be simple for the physician and well tolerated by the patients. The patient should be able to control the stimulation reliably after a short period of training and adjustment. The desirable exercise modes should be obtained in the paretic limbs without accompanying pain or discomfort. The use of the device should result in improved range of motion and flexion-extension torque at the involved joints. Progress: Electrodes have been designed and developed for the purpose of sensing EMG signals and stimulating the muscle from which those EMG signals were detected. A laboratory version of the EMG-controlled stimulator has been developed. The device is capable of processing two EMG signals and using them to control the onset and termination of stimulation pulses from four stimulation channels. Future plans: The tripolar electrodes and the EMG-controlled stimulator will be tested on a number of persons with hemiplegia. After the system has been miniaturized, subjects will use the device for exercise at home, and the effectiveness of the intervention will be assessed. 
Zi-Ping Fang, PhD Cleveland FES Center, USA 

The study examined the efficacy of functional electric stimulation (FES) and biofeedback (BFB) treatment of gait dysfunction in patients with hemiplegia after stroke. These two therapeutic modalities were tested alone and in combination in a prospective, controlled, randomized trial. The authors hypothesized that in concurrent use, these two modalities would complement one another. Thirty-six hemiplegic patients undergoing rehabilitation after stroke were accepted for study and randomized into four groups to receive either control, FES, BFB, or combined therapies. Each patient received 30 minutes of treatment three times per week for six weeks, in addition to their general rehabilitation program. Quantitative gait analysis was performed biweekly on each subject during the experimental therapy and for four weeks afterward. Thirty-two subjects completed the study. Combined therapy with BFB and FES resulted in improvements in both knee and ankle minimum flexion angles during swing phase that were statistically significant with p = 0.05 and p = 0.02, respectively. Velocity of gait, cycle time, and symmetry of stance phases also improved. The length of time elapsed since the stroke did not prove to be a significant factor. 
Cozean C.D. Ohio State University. Arch Phys Med Rehabilitation 

Use of electrical stimulation early in stroke rehabilitation may benefit recovery of function. This case report describes the clinical outcomes following electrical stimulation for the supraspinatus of a 25-year-old patient four weeks after a right-sided stroke. In this patient, use of electrical stimulation for a total of four hours in 4.5 weeks, appeared to have a number of benefits: subluxation was reduced and patient attention to the arm was increased. There was also a notable improvement in functional use of the arm when task-specific upper limb training was incorporated. Whilst not conclusive, the results of this case study reinforce the value of electrical stimulation in the early management of the upper limb in a stroke patient who clearly demonstrated inattention to his upper limb. The results also highlight the need for well controlled studies to investigate the benefits of electrical stimulation and to establish the optimal timing and parameters for this intervention. Therapists can then more effectively optimise effective upper limb rehabilitation following stroke. 
Mackenzie-Knapp M. School of Physiotherapy, La Trobe University, Bundoora, Australia. Aust J. Physiother.

This case report describes the first survivor with chronic stroke who was treated with percutaneous, intramuscular neuromuscular electrical stimulation (NMES) for shoulder subluxation and pain. The patient developed shoulder subluxation and pain within 2 mo of his stroke. After discharge from acute inpatient rehabilitation, he developed shoulder and hand pain, which was treated with subacromial bursa steroid injection and ibuprofen with eventual resolution. The patient remained clinically stable until approximately 15 months after his stroke-when he developed severe shoulder pain associated with shoulder abduction, external rotation, and downward traction. The patient could not tolerate transcutaneous NMES because of the pain of stimulation. At approximately 17 mo post-stroke, the patient's posterior deltoid, middle deltoid, and supraspinatus muscles were percutaneously implanted with intramuscular electrodes. After 6 wk of percutaneous, intramuscular NMES treatment, marked improvements in shoulder subluxation and pain, and modest improvements in activities of daily living and motor function were noted. One year after the onset of treatment, the patient remained pain free, but subluxation had recurred. However, the patient was able to volitionally reduce the subluxation by abducting his shoulder. The patient remained pain free for up to 40 months after the initiation of percutaneous, intramuscular NMES treatment. This case report demonstrates the feasibility of using percutaneous, intramuscular NMES for treating shoulder subluxation and pain in hemiplegia. 
Chae J. Dep.of Physical Medicine and Rehabilitation, Cleveland, USA. Am J Phys Med Rehabilitation 


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