Costochondral Joints.

The costochondral joints are primary cartilaginous joints between the anterior end of the rib and its cartilage. They let no movements.

Chondrosternal Joints.

These are joints between the medial ends of lst-7th costal cartilages and lateral border of the sternum. They’re frequently referred to as by clinicians as sternocostal joints.

First chondrosternal joint is primary cartilaginous joint (synchondrosis) and doesn’t allow any movement.

The costal cartilage of 1st rib is connected with manubrium sterni by a plate of fibrocartilage and thus it’s not a normal primary cartilaginous joint (synchondrosis).

2Nd to seventh costal cartilages articulate with the sternum by synovial joints. Every joint has just one cavity, with the exception of the 2nd costosternal joint where the cavity is splitted into 2 parts.