Thoracic Wall Flashcards
‘Suprasternal’ Jugular Notch
T2-T3
below the clavicle
Sternal angel
T4-T5 ribs 1-2
Manubrial sternal joint
Xiphoid process
T9-T11
bottom of the sternum
joint ossifies at 40 years old
Root of spine of scapula
spine of T3 but level of T4
Inferior angel of scapula
T7-T8
Rib 8
serratus posterior superior
elevates rib cage
serratus posterior inferior
depresses rib cage
Levator Costarum
elevates ribs
Transverse process C7-T11 to costal tubercle and costal angel
12 pairs of fan shaped muscles
Thoracic muscles/ intercostal muscles
All innervated by intercostal nerves from ventral primary rami of spinal nerve
internal intercostal muscles, innermost intercostal muscles, subcostal muscles, and transverse thoracis
External intercostal muscles
elevate ribs 'pocket' muscles Origin- tubercle Insert- costochondral junction Extend to sternum as external intercostal membrane
Internal intercostal muscles
Fibers run opposite of external
Lateral border of sternum to costal angle
costal portion- depresses
Chondral/ costal cartilage portion- elevates
Innermost intercostal muscles
3rd muscular layer
elevate and depress ribs
Found internally on posterolateral thoracic wall
Subcostal muscles
3rd muscular layer posteriorly
Muscle crosses more than one intercostal space
elevates ribs
Transverse Thoracis
3rd muscular layer anteriorly
lower sternum to internal surface of 2nd-6th costal cartilage
depresses ribs
Where does the anterior intercostal artery terminate?
6th intercostal space because it branches into superior epigastric and musculophrenic artery
Musculophrenic artery
supplies 7th and 9th spaces
branch from anterior intercostal artery
Where is the neurvascular bundle located for intercostal spaces?
between 2nd and 3rd muscular layer
How many intercostal spaces are there?
11 spaces
How many pairs of intercostal nerves are there?
11 pairs the 12th pair is the subcostal nerve
Posterior intercostal arteries
all 11 come from thoracic aorta
Superior intercostal artery
part of posterior intercostal arteries
comes from costocervical trunk
only supplies 1st and 2nd intercostal spaces
Intercostal nerves are also called?
thoracic nerves
Thoraco-Abdominal Nerves start and end where?
T7-T11
started as intercostal nerves and go onto anterior abdominal wall
Costodiaphragmatic Reflection
Where visceral pleura meets parietal pleura
sternoclavicular joint
between top of sternum and clavicle
synovial saddle joint
Manubriosternal joint
between manubrium and body of the sternum
cartilaginous and immovable
xiphisternal joint
between body of sternum and xiphoid process
cartilaginous and immovable
ossifies at 40 years of age
True ribs
ribs 1-7
directly attach to the sternum
False ribs
ribs 8-10
cartilage indirectly attaches to sternum
Floating ribs
ribs 11-12
Don’t attach to sternum but attach to thoracic vertebrae
Costovertebral Joints
superior articular/costal facet- vertebral body above the rib level
Inferior articular/costal facet- vertebral body at same level
Transverse articular/costal facet
transverse process of vertebra at same level
1st sternocostal joint
behind 1st rib, connects to sternum
cartilaginous and immovable
ossifies
sternocostal joint
attaches to lateral part of sternum where movement occurs
Ribs 2-7
synovial plane-type joint
slightly moveable
costochondral joints
between ribs and costal cartilage
cartilaginous and immovable
Forced expiration muscles
intercostal muscles
all abdominal muscles
Forced inspiration muscles
diaphragm
intercostal muscles
SCM
scalene muscle
Breast blood supply
Branches from Pectoralis Thoracoacromial Trunk
Lateral Thoracic artery- off axillary artery
Internal Thoracic artery- off common carotid artery
Breast Lymphatics
Axillary Lymphatic
Parasternal and clavicular nodes
Axillary lymphatics
75% of lymphatic drainage
- central axillary nodes
- apical axillary nodes
Parasternal and Clavicular Nodes
25% of lymphatic drainage
connects to other breast
Anatomy of the Breast
superficial fascia
deep fascia
retromammary space
suspensory (Cooper’s) ligament
