After a 36-week gestation, a 2,500-g female infant was born without complications via breech delivery. An Apgar score of 9 was obtained at three minutes. Her 22-year-old mother (gravida 2) was diabetic and receiving 30 units of isophane insulin suspension (NPH insulin) twice daily (morning and evening) to control her diabetes. Aside from maternal diabetes, there was no other history of familial disease, including congenital anomalies.
Physical examination showed an alert female infant with a sacral crease that was approximately 2.5 cm in length. She had an equinovarus deformity of the right foot, and the left foot was in a fixed dorsiflexed position. There were no spontaneous movements of the lower limbs. The hips were maintained in flexed external rotation, and the knees also were flexed. Withdrawal responses to pinprick were obtained only down to the waist level. The muscle mass of the lower limbs was decreased. The buttocks