Joseph Goodgold

An electromyographic study of induced myotonia in rats.

Abstract A systemic electromyographic study has been made of myotonia in rats induced by the subcutaneous injection of 25-azacholesterol. The myotonia was characterized by trains of discharges continuously varying in frequency and amplitude (myotonic potentials) and spontaneous random bursts of short duration potentials. The mean duration of the myotonic motor unit action potentials were 1.6 ± 0.2 msec compared to 2.6± 0.4 msec for the normal action potentials. It was found that the fast muscles (anterior tibialis and gastrocnemius) became profoundly myotonic whereas the slow muscle (soleus) was virtually unaffected.

A noninvasive technique to assess completeness of spinal cord lesions in humans

The effect of scalp stimulation delivered through electrodes overlying the motor cortex was evaluated in five healthy subjects and six patients with traumatic spinal cord injury. The latency to the onset of the electromyographic response was measured in the biceps brachii and abductor pollicis brevis muscles. In all the patients, latencies to the muscle (biceps brachii) whose innervation originated above the lesion were in the normal range; whereas, latencies to the muscle (abductor pollicis brevis) whose innervation originated below the lesion were prolonged. Electromyographic signals were recorded in muscles which showed no voluntary motor activity. No lateral differences in latencies were found in healthy subjects; however, in the patients, significant differences were obtained between the right and left abductor pollicis brevis muscles. The results of this study demonstrate that the spinal cord of patients with a lesion deemed to be clinically complete, contains nerve fibers which descend through the lesion and are capable of conveying impulses leading to muscle contraction.

Clofibrate-induced myotonia in the rat

Clofibrate induced electromyographic and contractile responses in rats consistent with myotonia.

Transmembrane potentials of human muscle cells in vivo

Abstract A system was designed and constructed which permits recording the resting and action potential of muscle fibers in man in vivo . The procedure involves passing a cannula containing a microelectrode through the skin into the muscle. No anesthesia is required. An average resting potential of 77.5 mv (with a standard deviation of 11.3 mv and a standard error of 1.2 mv) was observed for the anterior tibial muscle in normal subjects.

A light microscopic study of denervation atrophy in serial sections

Type I and type II muscle fibers from rat extensor digitorum longus muscle were sequentially followed in serial sections after various time intervals following denervation. The type II fibers exhibited the greatest degree of atrophy as well as showing a systematic diameter variability along its length.

Book Review of Stroke Rehabilitation

Excerpt To the editor: Although I was disturbed when I originally read the review ofStroke Rehabilitation(1) by Dr. McDowell (2), I did not write to the journal in recognition of the propriety of a...