The thoracic segment consists of 12 vertebrae (abbreviation Th). The features of the thoracic vertebrae are a relatively large body, a round vertebral foramen, tiled-sloping spinous processes, and fossae (characteristic dimples both on the tops of the transverse processes and on the upper and lower edges of the body). The aforementioned fosses are the place of attachment for the ribs. The rib tubercle is attached to the costal fossa of the transverse process, and the rib head is attached to the fossa located on the body of the vertebra. Due to the protective functions of internal organs, the thoracic section is the stiffest part of the spine. The thoracic section is physiologically curved backwards, forming the thoracic kyphosis (kyphosis thoracica). This kyphosis occurs when a child adopts a sitting position.