title: Bone maturity and thyroidal status at birth: role of the ultrasonographic evaluation of  the distal femoral epiphysis.
abstract: OBJECTIVE
  Thyroidal hormones are important for bone development, and ultrasonographic (US) evaluation of the distal femoral epiphysis (DFE) has recently been suggested as a new method for the assessment of skeletal maturity in infants. A delayed bone maturation, expressed by a smaller or absent DFE nucleus (in terms of DFE surface area, sum of the epiphyseal diameters, or DFE height and acetabular size), has been largely demonstrated in diagnosed hypothyroid infants, while no data analyze the role and meaning of the DFE dimensions (in terms of volume) in newborn before knowledge of the congenital neonatal screening results. The aims of the present study were to ultrasonographically evaluate the volume of DFE in newborns, and to determine whether it has any predictive role for the thyroidal status at birth.
  
  
  METHODS
  238 newborns (M/F: 121 /117) were evaluated. The gestational age, body weight and length at birth were registered. Neonatal screening for congenital hypothyroidism (CH), based on TSH levels on blood spot, was performed in all on the 3 rd day of life. The DFE volume was ultrasonographically evaluated, taking into account the three diameters of the DFE nucleus, within 48 hours of birth.
  
  
  RESULTS
  No newborn was found to have CH on neonatal screening. The DFE volume ranged between 0.00 cm and 0.61 cm (mean 0.14 ± 0.10 cm, median 0.13 cm). The DFE volume did not differ between males and females, while it was significantly greater in at term babies than in preterm babies. No differences in TSH values at screening were noted among the groups. The DFE volume was significantly related to gestational age, birth weight and length. A significant relationship was found between the DFE volume and TSH concentrations at screening.
  
  
  CONCLUSIONS
  US evaluation of DFE volume provides a simple method for assessing bone maturity at birth, which is related to gestational age, body weight and length at birth. Nonetheless, it has any predictive role for thyroidal status at birth, being not related to TSH levels on neonatal screening for CH.
authors.affiliation: Department of Pediatrics, University of Chieti, Chieti, Italy. alessavino@katamail.com
authors.forename: A
authors.initials: A
authors.lastname: Savino
authors.forename: S
authors.initials: S
authors.lastname: Carinci
authors.forename: I
authors.initials: I
authors.lastname: Bucci
authors.forename: G
authors.initials: G
authors.lastname: Sabatino
authors.forename: F
authors.initials: F
authors.lastname: Chiarelli
authors.forename: S
authors.initials: S
authors.lastname: Tumini
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging; D001724:Birth Weight; D001827:Body Height; D001846:Bone Development / Q000502:physiology*; D003409:Congenital Hypothyroidism / Q000000981:diagnostic imaging*; D004838:Epiphyses / Q000000981:diagnostic imaging*; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D007231:Infant, Newborn; D007719:Knee Joint / Q000000981:diagnostic imaging; D008297:Male; D015997:Neonatal Screening; D011237:Predictive Value of Tests; D012016:Reference Values; D013972:Thyrotropin / Q000097:blood; D014463:Ultrasonography
chemical_list: D013972:Thyrotropin