Showing papers by "Mark Hallett published in 1984"

Predictive value of urodynamic evaluation in newborns with myelodysplasia

Abstract: We examined 36 infants with myelodysplasia, using excretory urography, voiding cystourethrography, and urodynamic assessment in the newborn period and periodically thereafter to determine those at risk for decompensation of the urinary tract. Urodynamic evaluation showed 18 with dyssynergia of the detrusor and external sphincter, nine with synergic activity of the sphincter, and nine with no activity of the sphincter. Thirteen (72%) of the group with dyssynergia had or later were found to have hydroureteronephrosis, while this was the case in only two (22%) with synergy and one (11%) with absent activity. The conditions of these 16 patients improved after decompression by cutaneous vesicostomy or intermittent catheterization. Infants with dyssynergia of the detrusor-external sphincter are at high risk for deterioration of the urinary tract; they should be followed up closely, and intermittent catheterization should be started early. ( JAMA 1984;252:650-652)

Postural adjustments associated withrapid voluntary arm movements1.Electromyographic data

Abstract: Normal subjects made bilaterally symmetric rapid elbow flexions or extensions ("focal movement") while free standing or when supported by being strapped to a firm wall behind them (different "postural set"). In some trials a load opposed the movement two thirds of the way into its course. Electromyographic activity in leg and trunk muscles ("associated postural adjustments") demonstrated specific patterns for each type of movement. Activity in these muscles began prior to activity in the arm muscles and demonstrated a distal-to-proximal order of activation. The EMG patterns were characterised by alternating activity in the antagonist pairs similar to the triphasic pattern seen in the arm muscles. When the movement type was changed change of the pattern of the postural muscles occurred over several trials. It is concluded that the associated postural adjustments are pre-programmed motor activity linked to the focal movement, specific for the focal movement including anticipated events and the postural set.

Action tremor with alternating activity in antagonist muscles

Abstract: Action tremors due to alternating activity in antagonist muscles create different clinical manifestations. Tremors range in frequency from 2.5 to 7 Hz and may be brought out by either posture or goal-directed movement. Using physiologic criteria, tremors can be divided into groups with possible pharmacologic implications.

Shortening reaction of human tibialis anterior.

Abstract: The shortening reaction of tibialis anterior was observed in 6 of 25 normal subjects, in 6 of 40 patients with upper motor neuron syndromes, and in 11 of 17 patients with Parkinson9s disease. The latency of the shortening reaction was comparable with that of the latter part of the long-latency stretch reflexes. The magnitude of the shortening reaction increased with the velocity of the movement that produced it and increased with background voluntary force of plantar flexion in all but the patients with Parkinson9s disease. It was not affected by vibration in the patients with Parkinson9s disease. The presence of the shortening reaction was not correlated with the clinical impression of increased tone.

Physiologic analysis of the myoclonus of Alzheimer's disease.

Abstract: Ten patients with clinically diagnosed Alzheimer's disease, including three cases of trisomy 21 (Down's syndrome), developed a chronic myoclonic disorder. The technique of jerk-locked averaging of EEG activity was used to analyze the myoclonus. Seven subjects demonstrated a focal, contralateral central, negative cerebral potential antecedent to the myoclonic jerks. This EEG event differs from that previously reported to be associated with the myoclonus of subacute spongiform encephalopathy (Creutzfeldt-Jakob disease).

Clinical Characteristics and Prognosis of Vasculitic Mononeuropathy Multiplex

Abstract: • The initial appearance and course of 19 patients with mononeuropathy multiplex due to systemic vasculitis were evaluated. Neuropathy first occurred within one year of the onset of systemic vasculitis in all patients and within one year of the onset of rheumatoid arthritis in four of nine patients. Concurrent cutaneous arteritic lesions and elevated ESRs occurred more frequently in patients with rheumatoid arthritis than in those without it. The overall six-month and five-year survival rates were approximately 80% and 60%, respectively. Significant nerve improvement was noted in 86% of surviving patients after one year. There were no factors at initial appearance predictive of outcome.

Reflexes of the external urethral sphincter in children.

Abstract: • The electromyographic responses in the external urethral sphincter to electrical stimulation of the pudendal nerve and stretch of the external sphincter were analyzed in a pediatric population; the population included a group with recurrent urinary tract infections and a group with complete or almost complete upper spinal cord lesions. Electrical stimulation produced a response of reflex nature mediated in the sacral spinal cord, frequently beginning with two components that could be individually characterized and that behaved similarly to a flexor reflex. The response produced by stretch appeared to be similar to that produced by electrical stimulation.