Skin to calcaneus distance in the neonate

Background: Current recommendations for obtaining blood from neonates advise avoidance of the midline area of the heel and are based on postmortem studies. Objective: Because of the potential pain and tissue damage from repeated heel pricking in the same area, to investigate using ultrasonography whether the distance from skin to calcaneus is less at the midline than at the borders. Methods: One hundred consecutive healthy preterm and 105 consecutive healthy term neonates were studied 48-72 hours after delivery. The skin to perichondrium distance (SPD) was measured on two occasions by ultrasound at the external, midline, and internal areas of the heel. Findings: Mean SPD was 0.2 mm less at the midline than at the other sites. The proportion of measurements = 33 weeks gestation and term infants with an SPD = 33 weeks gestation. This means that soft tissue damage and pain from repeated pricking in the same area can be reduced.