The joint between the attachment of the 8th and the 9th rib to the 7th rib is a

The joint between the attachment of the 8th and 9th rib with the 7th rib is a synol joint. Most of the joints in the thoracic cavity- Interchondral, sternochondral, costoveebral and costotransverse joints, are plain synol joints because the thoracic cavity needs to expand during inspiration. The exception are : 1st sternocostal joint: Synahrosis (fibrous) Interchondral joint between the 9th and 10th cailages is never synol and sometimes absent. Costochondral joints are primary cailaginous joints (Synchondrosis) Midline joints like manubriosternal and xiphisternal joints are secondary cailagenous joints of symphysis type. Ref: Gray&;s Anatomy 41st edition Pgno: 940