THE EFFECT OF INTRAUTERINE BREECH POSITION ON POSTNATAL MOTOR FUNCTIONS OF THE LOWER-LIMBS

The effect of intra-uterine movement restriction on the development of motor functions was studied longitudinally by comparing infants born after uncomplicated breech position (n = 13) with control infants (ver tex position, n = 5-10). Before birth, fetal leg posture was studied a t regular intervals by means of real time ultrasound observations, and classified as complete (n = 1), inconsistent (n = 6), or incomplete ( n = 6) breech position. Limited extension of the hips, preference post ure and joint position in percentage of time (each until 12 weeks), wi thdrawal reflex and magnet response (until 26 weeks) and posture while sitting, standing and walking without support (up to 12-18 months) we re assessed longitudinally. The results showed statistically significa nt, positive relationships between intra-uterine breech position and n eonatal limited extension of the hip-joint, between limited extension of the hip-joint and the percentage of time that the hips are in flexi on during the first 12 weeks, between this flexion of the hips (in per centage of time) and an abnormally 'flexed' walking pattern at 12-18 m onths, and finally, between a positive magnet response at 6 months and an abnormal walking pattern at 12-18 months. These findings suggest t hat intra-uterine movement restriction of the legs can cause long term alterations in the development of motor functions (leg posture, refle xes and posture while walking), possibly mediated by alterations in pr oprioceptive feedback mechanisms.