Respiratory System: Osteology of the Thoracic Cavity (YBOD200)

This set covers the surface anatomy, skeletal framework, specific characteristics of ribs and vertebrae, and the joints/ligaments of the thoracic cavity as presented in the lecture.

Jugular notch

The superior border of the manubrium located between the sternal heads of the clavicle.

Sternal Angle of Louis

A bony landmark felt as a transverse ridge approximately $5\,cm$ below the jugular notch.

The Nipple (anatomical location)

Lies about $12\,cm$ from the midsternal line in the 4th intercostal space, though its position in females differs considerably.

True Ribs

Ribs $1$ to $7$, whose costal cartilage articulates directly with the sternum.

False Ribs

Ribs $8$ to $10$ (and $11$-$12$), whose costal cartilages articulate indirectly with the sternum via the costal cartilage of the rib above.

Floating Ribs

Ribs $11$ and $12$, which have no sternal articulation.

Costal margin

The boundary formed by the fusion of the costal cartilages of ribs $7$ through $10$.

Thoracic Vertebral Body

A heart-shaped structure containing $1$ or $2$ facets for articulation.

Thoracic Transverse Processes

Long, strong extensions that project posterior-laterally; T1-T10 have facets for articulation with rib tubercles, while T11 and T12 lack costal facets.

Typical Ribs

Ribs $3$ through $9$, which share similar characteristic features.

Atypical Ribs

Ribs $1$, $2$, $10$, $11$, and $12$, which have features not common to all ribs.

Costal groove

A groove on the rib shaft that lodges the intercostal vessels and nerve, abbreviated as VAN.

Scalene tubercle

A distinct feature on Rib $1$ for the attachment of the Scalene anterior muscle.

Manubrium

The upper part of the sternum lying at the level of $T3$ and $T4$ which includes the jugular notch and clavicular notches.

Xiphoid process

The smallest and most variable part of the sternum.

Costovertebral joint

A synovial plane joint for the articulation of the head of the rib with the corresponding vertebra and the one above it.

Costotransverse joint

A synovial plane joint involving the articulation of the tubercle of the rib with the corresponding vertebra.

Sternocostal joint (Rib 1)

A primary cartilaginous or synchondrosis joint where a thin, dense layer of fibrocartilage adheres the 1st costal cartilage to the manubrium.

Costochondral joint

A primary cartilaginous joint covered with hyaline cartilage between the costal cartilages and the anterior end of ribs; it allows no movement.

Interchondral joint

Synovial joints located between the costal cartilages of the $6th$, $7th$, $8th$, and $9th$ ribs.