Presentation
History of trauma.
Patient Data
There is a bifid right fifth rib (normal variant) noted, while the rest of the ribs are unremarkable.
Non-fusion of lateral ossification centers in the sternebrae, resulting in the mesosternum having a honeycomb-like appearance (normal variant).
Case Discussion
The adult sternum is comprised of three sections connected by secondary cartilaginous joints:
The manubrium (the first sternebrae) is located superiorly, the mesosternum (or body, comprised of the second to fifth sternebrae) is in the center, and the xiphoid process (the sixth sternebrae) is inferior to these other elements.
This rarely reported developmental abnormality is caused by the non-fusion of lateral ossification centers in the sternebrae, resulting in the mesosternum having a honeycomb-like appearance.