Periodontal Ehlers-Danlos syndrome Periodontal EDS (pEDS) causes dental problems, particularly inflamed or absent gums and poor tooth development, on top of typical features of cEDS. It is rare but can be inherited from one parent only, as only one faulty gene is needed to develop the condition.
Ribs 1, 2, 11 and 12 can be describes as âatypicalâ â they have features that are not common to all the ribs. Rib 1 is shorter and wider than the other ribs. It only has one facet on its head for articulation with its corresponding vertebrae (there isnât a thoracic vertebrae above it).
The Ribs (pp. 34-6) 1  There are usually 12 of these elongated flat bones on each side of the thorax. 2  The ribs curve anteriorly and inferiorly from the thoracic vertebrae. 3  Each typical rib has a head, neck, tubercle, and shaft.