Features of thoracic vertebrae ribs and sternum bones

Thoracic Vertebrae:

1. Body (Vertebral Body):
   • Larger and heart-shaped compared to cervical vertebrae.
   • Supports the weight of the thoracic cage.
2. Vertebral Arch:
   • Surrounds and protects the spinal cord.
   • Formed by the pedicles and laminae.
3. Spinous Process:
   • Projects posteriorly from the junction of the laminae.
   • Serves as a site for muscle and ligament attachments.
4. Transverse Processes:
   • Extend laterally from the junction of the pedicles and laminae.
   • Articulate with the ribs, forming costovertebral joints.
5. Superior and Inferior Articular Processes:
   • Form facet joints with adjacent vertebrae, facilitating movement and stability of the spine.
6. Costal Facets:
   • Located on the body and transverse processes for articulation with the ribs.
7. Thoracic Vertebral Foramina:
   • Enclose and protect the spinal cord as it passes through the vertebral column.
8. Inferiorly Directed Spinous Process:
   • A characteristic feature that contributes to the downward slope of the thoracic spine.

Ribs:

1. Head:
   • Articulates with the costal facets of thoracic vertebrae.
   • Divided into two facets: one for the vertebral body and one for the intervertebral disc.
2. Neck:
   • A constricted region immediately lateral to the head.
3. Tubercle:
   • Articulates with the transverse process of the corresponding thoracic vertebra.
4. Shaft (Body):
   • The main, curved portion of the rib.
   • Supports the intercostal spaces and provides structural integrity to the thoracic cage.
5. Costal Angle:
   • The point where the rib begins to curve anteriorly.
6. Costal Groove:
   • Located on the inferior border.
   • Houses the intercostal vessels and nerve.

Sternum:

1. Manubrium:
   • The superior portion.
   • Articulates with the clavicles and the first two pairs of ribs.
2. Sternal Angle (Angle of Louis):
   • The junction between the manubrium and body.
   • Marks the level of the second rib and the site of tracheal bifurcation.
3. Body (Gladiolus):
   • The central and longest part.
   • Articulates with the costal cartilages of the second to seventh ribs.
4. Xiphoid Process:
   • The smallest and most inferior portion.
   • Usually cartilaginous in youth, gradually ossifying with age.

These features collectively form the thoracic cage, providing protection to vital organs and serving as attachment points for muscles involved in respiration and upper limb movement. Understanding these structures is crucial in the assessment and diagnosis of conditions affecting the thoracic region.