Normal development of sacrococcygeal centrum ossification centers in the fetal spine: a postmortem magnetic resonance imaging study

Evaluation of sacral hiatus changes in children using ultrasound

Background and objectives

The intercornual distance in the sacral hiatus has yet to be studied precisely in children. This age-stratified, observational study aimed to clarify the changes in sacral hiatus dimensions and to quantify the correlations between the intercornual distance of the sacral hiatus and age, height, weight, and head circumference by using real-time ultrasonography.

Methods

The patients were stratified into three groups: neonates and infants, toddlers, and schoolchildren. In the operating room, the ultrasonic probe was placed at the sacral cornua to obtain a transverse view of the sacral hiatus, and the intercornual distance was measured three times in millimetres.

Results

The study included a total of 156 patients. The mean ± SD (95%CI) of intercornual distance in neonates and infants (<12 months) was 11.58 ± 1.79 (11.11-12.04) mm, 13.29 ± 1.97 (12.71-13.86) mm in toddlers (13-36 months), and 13.36 ± 2.49 (12.64-14.08) mm in schoolchildren (>36 months).The mean values of neonates and infants were different from those of toddlers and schoolchildren (p < 0.001), but it was similar between toddlers and schoolchildren (p > 0.05, 95 % CI mean difference -1.10 to 0.95).Intercornual distance was correlated with age, height, weight, and head circumference before one year of age (Spearman's R values > 0.7), but there was no correlation thereafter (Spearman's p value > 0.05).

Conclusion

In the first year after birth, the intercornual distance increases rapidly with body growth; after one year of age, the sacral hiatus dimension changes significantly. Ultrasound is superior for assessing the gradually ossified cartilage components in older children.

Normal fetal development of the cervical, thoracic, and lumbar spine: A postmortem study based on magnetic resonance imaging

OBJECTIVE

Before evaluating spinal pathology, it is essential to have knowledge of the normal spinal development at different gestational ages. This study aims to characterize normal spinal growth in human fetuses during the second and third trimesters.

METHODS

Postmortem 3.0 T magnetic resonance imaging (MRI) was performed on 55 fetuses at 17-42 gestational weeks by using three-dimensional T2-weighted sequences. Morphological changes and quantitative measurements of the fetal spine were assessed. The correlation between centrum ossification center volume (COCV) and gestational age was investigated.

RESULTS

The cervical, thoracic, and lumbar COCVs showed a positive relationship with gestational age (p < 0.05). No gender differences were found in the volumetric development of the cervical, thoracic, and lumbar centrum ossification centers (COCs). The average volumetric growth rate per COC was larger in the lumbar spine than in the cervical and thoracic spine. The L1-L5 COCVs also showed a linear positive relationship with gestational age.

CONSULTS

Postmortem 3.0 T MRI clearly demonstrated spinal changes in external contour and internal structure with gestational age. These findings expand our understanding of the early growth pattern of the human spine and could be further used to assess the developmental conditions of the fetal spine.

Congenital pelvic skeletal anomalies: Clinical and radiographic evaluation of newborns with gastrointestinal malformation

BACKGROUND

Congenital pelvic skeletal anomalies (CPSA) may appear as isolated defects or in association with other anomalies like congenital malformations of the digestive system (CMDS). Minor CPSA in non-syndromic patients are often overlooked. We aimed to assess the frequency of CPSA in newborns with CMDS to review the diagnostic approaches.

STUDY DESIGN

A retrospective review of medical records of 201 newborns who underwent X-rays for different neonatal indications was conducted. In 122 patients CMDS were diagnosed and classified according to the ICD-10 classification; 79 non-CMDS patients acted as controls. Pelvic skeletal segments were examined by X-rays.

RESULTS

Patients with CMDS, showed a higher risk of CPSA (Odds ratio 2.89; 95% CI 1.34 6.23) and other associated malformations in comparison to non-CMDS patients. Newborns with malformations of the large intestine have the highest risk of adjacent CPSA (48%), as it is a developmental defect originating from the same somite. In addition to skeletal agenesis/hypoplasia, we reported dysmorphic and bifid vertebras, trident ileum, and elongated neural arches.

CONCLUSIONS

The high incidence of CPSA in CMDS suggests performing a routine radiographic pelvic evaluation in cases of CMDS in order to identify complex phenotypes that could originate from the same developmental field.