[Electrophysiologic and anatomic parallels in the status of the external rectal sphincter in healthy children and in those with anorectal developmental abnormalities].
Electromyography was used to examine the external rectal sphincter in 44 neonate patients and in 24 patients aged 2 months to 3 years with different anorectal developmental abnormalities. The same examinations were performed in the control groups: in 30 normal neonates, in 15 premature (grade I-II) neonates, and in 64 normal children aged 1 to 14 years. According to the data of comparative morphometry, a study was made of the autopsy material of the external rectal sphincter from 15 full-term stillborns and 16 premature (grade I-II) stillborns as well as from 11 infants with anorectal developmental abnormalities who died within the first days after birth without any surgical intervention. It is concluded that in patients with anorectal developmental abnormalities, the contractility of the external rectal sphincter is considerably lower than in the respective weight groups of normal children and that such patients demonstrated the lack of the normal time-course of changes in its increase with age.