Influence of head position and head position-change on body posture in pre-term infants (A.T.N.R.).

Although body posture in pre-term infants is generally studied to describe developmental aspects, no consensus exists in literature about the influence of head position and head position change upon body posture in pre-term infants. In a weekly assessed longitudinal study of 15 healthy pre-term infants we extensively observed and analysed the flexion and extension patterns of the limbs in relation to a "spontaneous" head position turning from 32 to 36 weeks of conceptional age. A significant flexion/extension pattern was only observed with respect to the leg: turning of the head induced extension of the chin leg and flexion of the other leg. This pattern persisted during the total 3 hours observation sessions, occurred at every age and in all states, but rapidly disappeared within maximal 20 seconds after the head-turning. No consequent significant pattern was observed with respect to the other limbs or the various other combinations of limb posture changes analysed. An Asymmetric Tonic Neck Reflex was seen after only 3 percent of the head position changes.