Respiratory: Anatomy - Overview of the thorax Flashcards
Three major spaces of the thoracic cavity
- Mediastinum (central compartment)
- Right pulmonary cavity
- Left pulmonary cavity
What are the three main components of the thoracic wall?
Of the anterolateral aspect only (posterior aspect considered part of the back):
1. Thoracic cage
2. Intercostal muscles
3. Skin, subcutaneous tissue, muscle and fascia
Three types of ribs
- True: attached directly to sternum via costal cartilage (ribs 1-7)
- False: indirectly attached to sternum via costal cartilage of the rib above (ribs 8-10)
- Floating: end in posterior abdominal musculature without attaching to sternum (ribs 11-12, sometimes 10)
Four main features of a typical rib
- Head with superior facet (articulates with inferior costal demifacet of vertebral body above) and inferior facet (articulates with superior costal demifacet of vertebral body below, which shares the same number as the rib)
- Neck with tubercle (tubercle has articular part for attachment to transverse process of vertebra, and non-articular part for attachment of costotransverse ligament)
- Body with costal angle (marks lateral limit of deep back muscles)
- Costal groove on inferior internal surface of rib for neurovascular bundle
Describe the appearance and three unique features of the first rib
Appearance: broad, shortest, most sharply curved rib
Unique features:
- Single facet for articulation with T1
- Transverse grooves running across superior surface for subclavian artery (lateral) and vein (medial)
- Grooves separated by scalene tubercle (for attachment of anterior scalene)
Which ribs are considered typical and which are atypical?
Typical: ribs 3-9
Atypical: ribs 1-2, 10-12
Describe the appearance and one unique feature of the second rib
Appearance: larger, thinner, less curved than rib 1
Unique feature:
- Tuberosity for serratus anterior on superior surface
Describe the unique feature of ribs 10-12
Single facet only (T10-12 only have single facets on vertebral body/pedicle)
Describe the unique features of ribs 11-12
Short with no neck or tubercle
Single facet only
7 joints of the ribs and sternum, and brief description of each. Which are synovial and which are not?
- Joint of head of rib*: to superior and inferior (or single for T1 and T10-12) costal demifacets on vertebral bodies
- Costotransverse joint*: between rib tubercle and articular facet on transverse process; involves lateral and superior (to vertebral body above) costotransverse ligaments, and radiate ligament (to vertebral body above and below, and hypochordal bow)
- Costochondral joint**: between each rib and its costal cartilage
- Interchondral joint*: between adjacent costal cartilages of ribs 6-7, 7-8 and 8-9
- Sternocostal: first is primary cartilaginous** to manubrium, second* is synovial to manubrium and sternal body, ribs 3-7* are synovial to sternal body
- Manubriosternal***: between manubrium and sternal body, creates the Angle of Louis
- Xyphisternal***: between sternal body and xyphoid process
- synovial
** primary cartilaginous
*** secondary cartilaginous
Are ribs numbered for the vertebral body above or below their point of attachment?
Below
When do the three parts of the sternum ossify?
Middle to late adulthood
Vertebral level of jugular notch
Inferior border T2
What is the relationship between the clavicles and the superior zones of lymphatic drainage?
Above clavicles: lymphatic drainage to inferior jugular lymph nodes
Below clavicles: parietal lymph (from body wall and upper limbs) drains to axillary lymph nodes
Vertebral level of manubrium
T3/4