Prospective study of spinal muscular atrophy before age 6 years. DCN/SMA Group.
Spinal muscular atrophy (SMA) is a common neuromuscular disorder of childhood, associated with a high mortality rate during the first 2 years of life. Most practitioners expect patients with SMA to follow a progressive course with loss of muscle strength and function over 2-10 years. Counselling sessions with parents frequently emphasize the high mortality rate and risk for respiratory failure. The progressive nature of SMA has been attributed to the loss of motor neurons. Fifty-eight children, ages 6 years and younger, were examined between January, 1987, and April, 1992, as part of a large, multicenter collaborative study of SMA. Muscle function was evaluated at regular intervals using a standardized protocol that was demonstrated to be reliable. We determined a prevalence of 56% for tongue fasciculations, a prevalence of 22% for facial weakness, and persistent deep tendon reflexes in one patient. Improved motor function and acquired milestones during the study were documented. This work should contribute toward a better understanding of the natural history of SMA.
Iannaccone
S T
ST
Department of Neurology, University of Texas Southwestern Medical Center, Dallas 75235-8897.
Browne
R H
RH
Samaha
F J
FJ
Buncher
C R
CR
D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009048:Motor Skills / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D009460:Neurologic Examination; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology; D012026:Reflex, Stretch / Q000502:physiology; D014897:Spinal Muscular Atrophies of Childhood / Q000175:diagnosis* / Q000503:physiopathology; D013391:Sucking Behavior / Q000502:physiology