Electromyographic rehabilitation of facial function and introduction of a facial paralysis grading scale for hypoglossal-facial nerve anastomosis.

For reinnervation of facial paralysis, the XII-VII nerve anastomosis provides tone and mass contraction but rarely allows selective muscle control. The efficacy of EMG rehabilitation was evaluated in 30 patients who had no coordinated control of facial muscles. EMG signals from bilateral homologous facial muscle sites were converted into computer-compatible waveform traces and displayed on a video monitor. This facilitated modification of neuromuscular responses using behavioral shaping techniques. A six-point Facial Nerve Grading Scale was introduced for hypoglossal-facial nerve anastomosis to assess the results of EMG rehabilitation. Rehabilitation lasted from 3 to 18 months. Ten patients (33%) achieved the highest possible grading (II) with symmetry and synchrony of function and spontaneity of expression; 17 (57%) reached grade III, which allowed voluntary control of eye and mouth function; 3 (10%) showed minimal gains. It is suggested that neural plasticity allows therapeutic manipulation of central facilitory and inhibitory mechanisms, and possible unmasking of neural connections between the ipsilateral VII and XII nerve motor nuclei which leads to improved facial function.

Hypoglossal-facial nerve anastomosis and electromyographic feedback rehabilitation.

Electromyographic (EMG) feedback has been proposed to enhance rehabilitation following hypoglossal-facial nerve anastomosis. Sixteen of 25 patients who underwent hypoglossal-facial nerve anastomosis with and without postoperative EMG rehabilitation were videotaped for evaluation of facial movement by four observers unaware of these patients' rehabilitation therapy. Using a House Facial Nerve Grading System and intragroup comparison, a trend discernible in this preliminary study indicates a chance for better facial function with EMG feedback rehabilitation.

Helping hemiparetics to help themselves. Sensory feedback therapy.

Despite the presence of some voluntary movement, the loss of discrete control impairs functioning of the arm and hand in most hemiparetics. Seventy hemiparetic patients, aged 12 to 78 years, were treated and followed up for six months to three years. Electromyographic activity monitored from dysfunctional primary movers during attempted movement was displayed to the patients as a continuous oscilloscopic trace, reflecting generated muscle activity and allowing its quantification. Coupled with operant conditioning techniques, these displays were modified gradually by reinforcing the patient's effort with auditory feedback during successive approximations to a desired level. Such therapeutic use of electromyographic displays often resulted in a progressive improvement of voluntary movement. More than half the patients acquired and retained purposive movements that meaningfully improved their functional capabilities.

Sensory feedback therapy in patients with brain insult.

Brain insults, regardless of etiology, may disrupt the CNS servosystems concerned with patterned voluntary movements and result in disorders of such movement. To aid functional recovery, we applied in these patients oscilloscopic display of digitally integrated EMG, monitored from malfunctioning primary movers, during attempted execution of movement (sensory feedback therapy). Such display provided the patient with an immediate and continuous visual feedback loop reflecting the events underlying the movement and occuring in the monitored muscle (force, displacement and rate). This information is essential for motor control of patterned voluntary movement. Coupled with auditory reward for optimal performance, such feedback also assumed reinforcing qualities and motivated the patient to execute voluntary movements with progressive improvement. Sixty patients with longstanding CNS insult, resulting in motor impairment, were treated and followed for periods of four months to four years. One half of these patients learned and retained voluntary movements that significantly improved their functional capabilities. Temporary substitution of feedback information about fundamental events in dysfunctional muscles can apparently be of lasting value in treatment of some patients with brain insult.

EMG feedback therapy: review of treatment of 114 patients.

Advances in the understanding of the relationship of proprioceptive (kinesthetic) feedback to motor physiology have prompted the study of therapeutic effects of audiovisual displays of EMG activity. Patients with various manifestations of disturbed neuromotor control were studied prospectively for three years. This group included 114 patients with hemiparesis, torticollis, dystonia, and spinal cord or peripheral nerve injury. Initially, all but one of these patients had some residual volitional motor activity, which was insufficient for adequate function, and all patients had had conventional therapy with little or no functional recovery. Prior to EMG feedback therapy, the duration of illness was from three months to 35 years. The shaping of a patient's motor responses usually occurred gradually, often over an 8 to 12 week period. This modification was accomplished by feeding processed audio-visual signals back to the patient. These signals were proportional to the degree of activity of the muscles responsible for the defective function. The concept of microvolt-second, as a unit of muscle activity, is introduced and defined. Patterned movements, which were previously defective were observed to improve to varying degrees. Following the initial course of treatment, reinforcement was required by some patients. The mechanisms of improvement after EMG feeback therapy are not well understood; however, some hypotheses are presented. The results of this study indicate that EMG feedback therapy may induce significant functional recovery in patients with disturbed neuromotor control.

Integrated EMG feedback in the management of spasmodic torticollis and focal dystonia: a prospective study of 80 patients.

In summary, then, without consideration of specific circuits or transmitter agents, one can conceive of a hypothetical model that involves both learning and the functional nature of the defect in torticollis and focal dystonia to describe the results obtained. The model must be further elaborated upon and tested, preferably in a quantitative manner. Naturally, the specific finding of a defective transmitter agent (e.g., GABA) such as described in parkinsonian syndrome (dopamine) or the interruption of a specific pathway that causes and improves a dyskinesia is desirable. In this chapter we have described the use of integrated EMG feedback for the treatment of focal dystonia or spasmodic torticollis. Although we have achieved significant results, it remains clear that further research in the treatment of these disorders is required. However, since this treatment does not require medication or surgery and the possibility for significant improvement is greater than 40%, it should be attempted in patients with focal dystonia or torticollis prior to other forms of therapy. SFT should be considered as a standard mode in the medical armamentarium used for the treatment of these disorders, either primarily or in conjunction with other forms of medical, surgical, and physical therapy.