Other joints of thoracic wall
Manubriosternal joint is a midline joint which is a symphysis. The surfaces are covered by hyaline cartilages. There is an intervening disc of fibrocartilages. It may ossify in elderly people. Sometimes (30% of people) cavitation may occur in the intervening disc. After cavitation the joint becomes as synovial joint. It is a degenerative change. Although it doesn't change the fact that, it is a symphysis.
Every rib makes costochondral joint with its costal cartilage. It is a primary cartilaginous joint. Costalcartilages represent the unossified part of rib.
It is a small synovial joint. It can be seen between sixth and seventh, seventh and eighth and eighth and ninth costalcartilages. Ninth and tenth are connected by ligamentous fibres.
It is also a midline joint. It is a symphysis between body of sternum and xiphoid process. It commonly ossifies at middle age.
First costal cartilage
1st costalcartilage articulates with manubrium. It is a primary cartilaginous joint. Thus manubrium and 1st ribs are fixed with each other and move as one.
Second - seventh costal cartilages
2nd to 7th costalcartilages articulate with body of sternum by synovial joint. 2nd costal cartilages articulate with body of sternum and manubrium.