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).
When the diaphragm contracts in inspiration, initially the lower ribs are fixed and the dome of the diaphragm descends, thus increasing the vertical diameter of thorax. Respiration involves Inspiration and Expiration which are accompanied by the alternate increase and decrease of the volume of thoracic cavity.y elevation of first and second ribs by scalene muscles which is otherwise fixed in quiet respiration, by elevation of clavicle by sternocleidomastoid and other muscles also elevate the ribs, thus help expanding the thoracic cavity and ultimately in inspiration. Accessory muscles involved in forced expiration are.