Bone Abstracts

Backround: Usually, skeletal development and bone age in children are still examined by x-ray. In obstetrics the use of fetal ultrasonography (US) of the distal femoral epiphyseal (DFE) and proximal tibial epiphyseal (PTE) ossification centers helps to identify intrauterine growth retardation. And US has been shown to be an excellent tool to assess the mineralization of bones. First ultrasound studies were following the mineralization of bones in young infants.

Objectives: To evaluate the skeletal development of the proximal femur epiphysis (PFE), of the DFE and the PTE by musculoskeletal ultrasound in premature and mature newborns. To perform approximate age related values for the size of the ossification centers and the epiphyseal cartilage thickness.

Methods: The ossification stages of the PFE, DFE and of the PTE were determined in 180 premature and mature newborns at a biological age of 25–47 weeks in this prospective study. The size of visible ossification centers and cartilage thickness between the ossification zone and the cartilage surface in the DFE and PTE was measured. The visible onset of mineralization was recorded.

Results: The onset of visible mineralization of the DFE was recorded earliest in the 30th mature week and of the PTE earliest in the 31st mature week. The onset of visible mineralization in the PFE was earliest seen in the 43rd mature week. The mean size of the ossification centers of the DFE and the PTE (measured in two planes) was increasing by the maturity. In a comparison of three age groups (biological age 30–33 weeks, 34–37 weeks and 38–41 weeks), the mean size of the ossification centers was significant increasing (P<0.01). There was no significant difference between male and female newborns and between both sides.

Conclusions: MSUS is an excellent tool to follow skeletal development in premature and mature newborns. Our preliminary data of ossification center sizes and cartilage thickness emphasize that ultrasound may be an useful tool to calculate the mature age of neonates.

Disclosure: The authors declared no competing interests.