Thoracic Cage | The University Of Western Ontario

University:
The University Of Western Ontario
Course:
ANAT 2200B | Systemic Anatomy of the Human Body
Academic year:

2022
Views:

192

Pages:

3
Author:

Kyuwon J.

Thoracic Cage ● Protection of thoracic organs ○ Heart, lungs, great vessels ○ Support on pectoral girdle + upper limbs ○ Attachments of muscles ■ Respirations ■ Posture ■ Upper limbs ○ Assists in respirations ■ Flexible rib movements ■ Up and down thoracic volumes ● Components ○ 12 thoracic vertebrae (posterior) ○ 12 pairs of ribs and costal cartilages (lateral) ○ Sternum (anterior) ● Ribs ○ 12 pairs ○ True ribs (1-7) ■ Connecting directly to sternum through costal cartilages ○ False ribs (8-10) ■ Sternum join indirectly through cartilage in rib 7 ○ Floating ribs (11-12) ■ No anterior connection ■ Floating in middle of the body ● Rib features ○ Head ■ 2 facet on vertebral articulation ● Same level ● One above ○ Neck ■ Between head and tubercle ○ Tubercle ■ Articulation in transverse process in vertebra ○ Shaft ■ Thin, curved , costal groove ● Special ribs ○ Rib1 ■ Shortest , broadest ■ Single facet on head ■ Groove used for subclavian vessels ○ Rib 2 ■ Thinner, longer ■ Tuberosity on serratus anterior ○ Rib 10-12 ■ Single facet ■ Rib 11-12 short ■ No neck + tubercles ● Sternum ○ Manubrium : superior portion on articulation with clavicle + 1st ribs ■ Jugular :notch ■ Sternal angle : junction of body ● Landmark for rib 2 +T4+T5 level ■ Body : articulation in costal cartilage 2-7 ■ Xiphoid process : ossifies with age Note: sternum is common site for bone marrow biopsy Thoracic cage ● Costovertebral joints ○ Head of rib = vertebral body ● Costotransvers joints ○ Tubercle = transverse process ● Sternocostal joints ○ Costal cartilage = sternum ● Interchondral joints ○ Between cartilage of ribs 7-10 Movements in Respirations