Postnatal maturation of peripheral nervesin preterm and full-term infants

Abstract

The conduction velocity of the ulnar and posterior tibial nerves was measured serially during the first year of life in normal preterm and full-term infants. At birth the preterm infants had significantly slower velocities than did the full-term infants. The conduction velocities of the ulnar and posterior tibial nerves remained significantly slower until 9 months and 3 months of age, respectively. When related to postconceptional age, however, the conduction velocities in preterm infants were slower than those of full-term infants only at 40 weeks; from 44 weeks onward there was no significant difference in the mean velocities. The rate of maturation of the peripheral nerves of preterm infants is thus retarded for only a few weeks after birth; subsequently it is the same as that of full-term infants of similar postconceptional age. The conduction velocity of the ulnar and posterior tibial nerves was measured serially during the first year of life in normal preterm and full-term infants. At birth the preterm infants had significantly slower velocities than did the full-term infants. The conduction velocities of the ulnar and posterior tibial nerves remained significantly slower until 9 months and 3 months of age, respectively. When related to postconceptional age, however, the conduction velocities in preterm infants were slower than those of full-term infants only at 40 weeks; from 44 weeks onward there was no significant difference in the mean velocities. The rate of maturation of the peripheral nerves of preterm infants is thus retarded for only a few weeks after birth; subsequently it is the same as that of full-term infants of similar postconceptional age.