Thorax Flashcards
What are the numbers of the typical ribs?
3-9
Where do the ribs connect on the vertebrae?
The rib has 2 facets that connect to the superior facet of the same number rib and the transverse process of that same vertebrae
Describe the first ribs articulation
The 1st rib is wide, flat, and small and it only articulates with T1
What are the components of the sternum?
- Manubrium
- Jugular Notch
- Sternal angle
- Body
- Xiphoid process
Describe the sternal angle
Where the manubrium meets the sternum at the 2nd costal cartilage
What is the last rib to have costal cartilage?
7th rib
How many pairs of true ribs are there?
7 pairs
Where does the superior portion of the diaphragm attach?
The xiphoid process (at the inferior limit of the thoracic cavity)
Describe the xiphoid-sternal joint
Connects the xiphoid process with the body of the sternum
What are the false ribs?
8, 9, 10
Where do the false ribs attach?
To the costal cartilage right above it
What is the costal cartilage that is connected to the false ribs called?
The costal margin
What are complications of a rib fracture?
-Puncture the pleura, lung, spleen, diaphragm
What is a median sternotomy?
-Surgical splitting down the middle plane
What are the floating ribs?
Ribs 11 and 12
Where do the floating ribs articulate?
Only articulate posteriorly
-anteriorly they just end up in muscle
What is protected by ribs 11 and 12
Superior parts of the kidney
What travels in the recess of the ribs?
Neurovascular bundles
What are the 4 joints of the thoracic wall?
- Costovertebral
- Costotransverse
- Costochondral
- Sternocostal
Describe the costovertebral joint
The head of the rib with the body of the vertebrae
What type of joint is the costovertebral
-Synovial–> planar
What types of joint are all the joints of the thoracic wall?
They are all different
Describe the costotransverse joint
These are between 7 and 8
-Pivot joints
Describe the costochondral joints
-only ribs 1-10
What type of joints are the costochondral
- primary cartilaginous joints
- synchondroses
- stay cartilage throughout life
What type of joint is the sternocostal joint?
- The 1st rib has a synchondroses
- All the rest are synovial planar
What is the goal of inspiration
increase volume so pressure drops
What determines your longitudinal increase?
- Diaphragm
- Contraction of the diaphragm makes the area longer or shorter
- Breath in= diaphragm goes down
What controls the medial and lateral increase in size?
- The bucket handle
- Used for lower ribs 8-10
- Gliding occurs on the tubercle of the first rib and the transverse processes of the vertebrae
- (lifting the handle more towards the side increases the medial and lateral diameter)
What is responsible for the anterior and posterior increase in size?
- The pump handle
- The costotransverse ligaments of ribs 4-7
- They rotate so this is why they are pivot joints
- The tubercle is the main moving part
What does rotation at the middle thorax allow?
-For the AP to increase
Describe the sternoclavicular joint
- Synovial (saddle)
- Functions like a ball and socket tho
- Contains an articular disc
What are the ligaments of the sternoclavicular joint?
- Anterior
- Posterior
- Interclavicular
Describe the superior thoracic aperature
- Almost in a horizontal plane
- Along the first rib and the costal cartilage and T1 vertebrae, manubrium
- Nicknamed the thoracic inlet
Describe the inferior thoracic aperature
- Covered by the diaphragm
- T11, T12, costal margin, costosternal joint, ALL,deep surface of xiphoid-sternal joint
- Not in a plane
- Nicknamed the thoracic outlet
Describe thoracic outlet syndrome
- Manifestation of the upper thorax
- T1 nerve is compressed
- Blood and nerve impairment
- Ischemia, numbness, tingling
This is the musculotendoneous sheath that covers seperates the thorax from the abdomen
Diaphragm
Where is the hemi-diaphragm?
-5th rib and 5th costal cartilage
During breathing, where does your liver rise?
5th rib
Where does your spleen rise?
-Costal cartilage
Describe external intercostals
- Run supralaterally
- start at the vertebral bodies but do not do all the way to the sternum
How many intercostalis are there total?
22
What splits the innermost intercostalis?
-Split by the neurovascular structures
What are the internal, external, and innermost intercostalises intervated by?
Intercostal nerve
What is the main job of the intercostal muscles?
- Maintain tone and space
- So we don’t collapse or explode
- Can move ribs with increased respiration need
- Reflexive
What are the anterior axioappendicular muscles?
- Pec major and minor
- Subclavius
- Serratus anterior
Describe the significance of paralysis of the serratus anterior
- Nerve lies on the surface so it is vulnerable
- Winged scapula and lack of full abduction result
Describe the action of transverse thoracic muscle
- Don’t have uniform action bc they are at different angles
- Mainly there for proprioception
Describe the subcostal muscle
- spans more than 1 intercostal space
- always ALWAYS on the posterior wall
Where does the diaphragm sit mostly
-On the costal margin
This is a musculotendonous division
Diaphragm
All the muscle fibers of the diaphragm attach to this
-The central tendon
What are the 3 components of the muscular part of the diaphragm?
- Sternal Part
- Costal Part
- Lumbar Part
What bony landmark is included in the sternal part
The xiphoid process
What bony landmarks are included in the costal part?
-The inferior 6 costal cartilages and ribs
What bony landmarks are included in the lumbar part?
- Bodies of all lumbar vertebrae
- AKA CRURA
What provides motor innervation to the diaphragm?
-Phrenic nerve
Does the phrenic nerve have sensory input?
-Yes- for the pleura and the lining of the pericardium (central parts)
Where do the peripheral parts receive innervation from?
-Sensory from intercostal nerves
Describe the right crus
- Around the esophagus hiatus
- Not a circular muscle
- External structure that is part of the diaphragm that acts kinda like an sphincter
Describe the left crus
- Smaller and tighter
- Wraps around the aortic hiatus
What rib level is the caval hiatus found?
T8 and 9
What structure sits on top of the caval hiatus?
- The right atrium
- The pericardium is anchored here
What holds the heart to the diaphragm?
-Pericardial phrenic ligaments
Where does the right crus arise from?
-First 3 or 4 lumbar vertebrae
Where does the left crus arise from?
-The first 2 or 3 lumbar vertebrae
What 3 things form the aortic hiatus?
- Median arcuate ligament
- Right crus
- Left crus
This is fibrous and connects the right and left crura
The median arcuate ligament
This is a thickening of the fascia that covers the psoas major
-Spans between the lumbar vertebral bodies and the tip of the transverse processes of L1
Medial arcuate ligament
Where does the lateral arculate ligament span?
-L 12 transverse process to the tip of the 12th rib