INCREASED MUSCLE STRENGTH IN PARALYZED PATIENTS AFTER SPINAL-CORD INJURY - EFFECT OF BETA-2-ADRENERGIC AGONIST

The administration of beta-2 adrenergic agonists in experimental anima ls result in an increased strength of skeletal muscle. In this study, we evaluated whether a beta-2 adrenergic agonist, metaproterenol, had an effect on muscle size and strength in a group of patients with musc ular atrophy following spinal cord injury. Ten male subjects were rand omly divided into 2 groups and agreed to participate in a prospective, double-blind, placebo-controlled, and crossover study. Metaproterenol (80 mg/day), or placebo, was administered orally for a period of 4 we eks. Muscle strength was measured by a force transducer interfaced wit h a microcomputer. Muscle size was calculated and expressed as a cross -sectional area of upper arm and forearm using a formula. Metaproteren ol induced a significant increase of muscle strength in both groups of subjects, compared with placebo (p <.001). Similarly, there was an in crease in a muscle size in the forearm following the administration of metaproterenol. Our data indicate that beta-2 adrenergic agonists may improve both muscle strength and size in patients with muscular atrop hy following spinal cord paralysis. (C) 1995 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medici ne and Rehabilitation