which pair of ribs articulates with the sternum at the sternal angle
Sternal angle The sternal angle, which varies around 162 degrees in males,[3] marks the approximate level of the 2nd pair of costal cartilages, which attach to the second ribs, and the level of the intervertebral disc between T4 and T5.[2] In clinical applications, the sternal angle can be palpated at the T4 vertebral level.