Normal development of costal element ossification centers of sacral vertebrae in the fetal spine: a postmortem magnetic resonance imaging study
This postmortem magnetic resonance imaging (MRI) study of the fetal spine aimed to describe the timing of appearance, shape, volume, and relative positions of the S1–S3 costal element ossification centers (CEOCs).
We obtained sagittal 3D dual-echo steady-state with water excitation T2 images of the entire spine in 71 fetuses (gestational ages (GAs), 17–42 weeks). Computed tomography and histological examinations were performed on two fetal specimens (GAs, 21 and 30 weeks) to validate the MR images. The presence/absence of each sacral CEOC was recorded according to the GA. CEOC volume was measured. We analyzed the CEOC position relative to the vertebral column and ilium.
The S1, S2, and S3 CEOCs first appeared at 23, 22, and 29 weeks, respectively. The S1 and S2 CEOCs could be detected in all fetuses with GAs of ≥ 30 weeks and ≥ 35 weeks, respectively, while the S3 CEOCs were variably present until term. The percentages of detection of the S1 and S2 CEOCs were significantly greater than that of the S3 CEOCs at each GA. At S1 and S2, the CEOC volume increased exponentially with GA. The relative positions of the S1 and S2 CEOCs, but not the S3 CEOCs, significantly correlated with GA (P < 0.001).
We have described the timeline of appearance as well as the volume and position of the S1–S3 CEOCs in the fetal spine on postmortem MRI according to GA.
KeywordsFetal spine Costal element ossification center Sacrum
Costal element ossification center
Centrum ossification center
Neural arch ossification center
- 3D DESS WE
Three-dimensional dual-echo steady-state with water excitation
Magnetic resonance imaging
Compliance with ethical standards
This study was funded by the National Natural Science Foundation of China (Project Code: 31371213) and the Natural Science Foundation of Shandong Province, China (Project Code: ZR2013HM091).
Conflict of interest
The authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the Shandong University Ethics Committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
- 2.O’Rahilly R, Müller F, Meyer DB (1990) The human vertebral column at the end of the embryonic period proper 4. The sacrococcygeal region. J Anat 168:95–111Google Scholar
- 3.Francis C (1951) Appearance of centers of ossification in the human pelvis before birth. Am J Roentgenol Radium Ther 65(5):778–783Google Scholar
- 4.Bardeen CR (1905) Studies of the development of the human skeleton. (A). The development of the lumbar, sacral and coccygeal vertebrae. (B). The curves and the proportionate regional lengths of the spinal column during the first three months of embryonic development. (C). The development of the skeleton of the posterior limb. Am J Anat 4(3):265–302. https://doi.org/10.1002/aja.1000040302 CrossRefGoogle Scholar
- 6.Widjaja E, Whitby EH, Paley MN, Griffiths PD (2006) Normal fetal lumbar spine on postmortem MR imaging. AJNR Am J Neuroradiol 27(3):553–559Google Scholar
- 7.Thakkar RS, Flammang AJ, Chhabra A, Padua A, Carrino JA (2011) 3T MR Imaging of Cartilage using 3D Dual Echo Steady State (DESS). http://www.healthcare.siemens.pl/siemens_hwem-hwem_ssxa_websites-context-root/wcm/idc/groups/public/@global/@imaging/@mri/documents/download/mdaw/mtqw/~edisp/3t_mr_imaging_of_cartilage_using_3d_dual_echo_steady_state-00011808.pdf. Accessed March 2011
- 9.Chabert S, Villalobos M, Ulloa P, Salas R, Tejos C, San Martin S, Pereda J (2012) Quantitative description of the morphology and ossification center in the axial skeleton of 20-week gestation formalin-fixed human fetuses using magnetic resonance images. Prenat Diagn 32(3):252–258. https://doi.org/10.1002/pd.2942 CrossRefGoogle Scholar
- 10.O'Rahilly R, Müller F, Meyer D (1990) The human vertebral column at the end of the embryonic period proper. 3 The thoracicolumbar region. J Anat 168:81–93Google Scholar
- 13.Flecker H (1942) Time of appearance and fusion of ossification centers as observed by roentgenographic methods. AJR 47:97–159Google Scholar