Thoracic Wall And Cavities (Ch. 4: p. 291 - 311) Flashcards
What are the three parts of the thoracic cavity
Mediastinum (heart, vessels, trachea etc.)
L pul. Cavity
R. Pul. Cavity
Define the true thoracic wall
Thoracic cage, the intercostal muscles, skin, tissue, fascia, etc on the anterior portion, not the posterior portion
What are the three types of ribs
True
False
Floating (Free)
Define True Ribs
Number?
Aka
Special why?
Number 1 - 7
Aka vertebrocostal ribs
Attach directly to sternum through own costal cartilage
Define False Ribs
Number
Aka
Special why
Ribs 8 - 10
Aka vertebrochondral ribs
Connected to sternum through cartilage of rib above them
Define Floating ribs
Number
Aka
Special why
11, 12
Aka vertebral ribs
End in posterior abdominal muscles
Define typical ribs
Number
Special why?
3 - 9
Has head with 2 facets
Tubercles
Body with costal angle
How do typical ribs articulate with the thoracic vertebra
Attache to superior costal facet of same number vertebra, as well as inferior costal facet of vertebra superior to it
What are some distinguishing characteristics of rib #1
Broadest and shortest
Has 1 facet for articulation with T1
Has two grooves for subclavian V (ant.) and subclavian A. (Post.)
Has scalene tubercle
Define scalene tubercle
Separates grooves on Rib #1
Attachment site for scalene M.
What is special about Rib #2
Has tuberosity for serratus Ant. M.
What is special about rib 11/12
No neck or tubercle and only 1 facet
What N. Is below Rib 12
Ant. Ramus of SN T12
What are the three parts of the sternum
Manubrium
Body
Xiphoid process
Most superior notch of manubrium
Jugular notch
What attaches to the L and R clavicular notches
SC joints and clavicles
How many costal notches are there
7 for attachment of costal cartilage
What are the 4 transverse ridges of the sternum remnants of
4 sternebrae (primordial segments of sternum) which fuse around age 25
Where does the xiphoid process stop
T10
When is the xiphoid process ossified by
Age 40
What are the borders of the superior thoracic aperture
Posteriorly - T1
Laterally - 1st pair of ribs
Anteriorly - superior border of manubrium
What are the borders of the inferior thoracic aperture
Posteriorly - T12
Posteriolaterally - 11/12 ribs
Anteriolaterally - costal cartilage of ribs 7 - 10
Anteriorly by xiphisternal joint
All functions of inspiration
Muscles contract
Cavity increases
Pressure decreases
Ribs move up and out
All functions of expiration
Muscles relax
Cavity decreases
Pressure increases
Ribs move down and in
External intercostal muscles are responsible for what
Inspiration
Internal and innermost intercostal muscles are responsible for what
Expiration
The NVB bundle runs where in regards to the rib
Under the rib that it corresponds with
The NVB runs where in regards to the intercostal muscles
Between the internal and innermost
External Intercostal M.
O I N A A
O: inferior border of ribs (posteriorly)
I:
Superior border of rib below (points anteriorly)
N: Intercostal N.
A: Elevate Ribs
Art:
Which direction do the External Intercostal ribs point
Anteriorly
The EIM’s are replaced by what anteriorly
Ant. Intercostal Membrane
The EIM and IIM run how in regards to each other
Perpendicular
Internal Intercostal M.
O I N A A
O: inferior border of ribs (anteriorly)
I: superior border of ribs (posteriorly)
N: Intercostal N.
A: Depress Ribs
Art:
How do the IIM point
Point posteriorly
What is the IIm replaced by posteriorly
The posterior intercostal membrane
Innermost Intercostal M.
O I N A A
O: inferior border of ribs
I: superior border of rib below
N: Intercostal N.
A: unknown
A:
Define manubriosternal joint
Symphysis joint at the sternal notch
Brings together manubrium with body of sternum
Define xiphisternal joint
Primary cartilaginous (synchondrosis) joint at 7th costal notch
Brings together body with xiphoid process
Define the sternocostal joint
Planar synovial joint (2 - 7) [rib 1 is a synchondrosis]
Bound by ant./post. Radiate Sternocostal L.
Brings together sternum and costal cartilages
Define costochondral joint
Synchondrosis joint
Brings together ribs with costal cartilage
What is the Dx of a sternocostal joint vs a costochondral joint
Sternocostal joint = dislocation
Costochondral joint = separation
Define costovertebral joint (type)
What is it bound by
What does it brings together
Planar synovial joint
Bound by
Radiate L. [head of rib to vertebral body]
Intraarticular L. [head of rib to the interverterbal disc]
Articular capsule (strongest anteriorly as the radiate L.)
Brings together ribs and vertebra
Define costotransverse joint (type)
what two L.’s are associated with it and what do they connect
What does it bring together
Planar synovial joint
Bound by superior costotransverse L.’s - neck of the rib to the transverse process one vertebral segment superiorly
and
lateral costotransverse L.’s - tubercle of the rib to the transverse process
Joins ribs to transverse processes
First rib fx is due to what
Severe trauma
Which ribs are most commonly fx
Middle ribs
Rib fx usually result from what
Blows or crush injuries
Where is the weakest part of the rib
Just anterior to its angle
Define rib movement with flail chest
Paradoxical (counter movement)
Which approach to a thoracotomy is more satisfactory of entry into chest wall
Lateral approach
What is more common, cervical ribs or extra lumbar ribs
Cervical
Ossified xiphoid process may produce what in the elderly
A feeling of a “pit in their stomach”
They think it’s cancer
A sternal fx is usually what/ displacement of the bone fragment is not likely due to what
A comminuted fx.
Not likely due to deep fascia
Most common site for sternal fx. In the elderly
The sternal angle which result sin a dislocation of the manubriosternal joint
The sternal body is often used for what procedure
Bone marrow needle biopsy
Define complete sternal cleft
Heart protrudes from sternum (ectopia cordis)
Define sternal foramen
Hole in sternum due to incomplete fusion
Define pectus excavatum
Funnel chest, receding in
Define pectus carinatum
Projecting chest
Paralysis of the diaphragm involves what N.?
The phrenic N.
Chest tube is usually inserted where
5th or 6th intercostal space laterally
What does the superior articular facet of a typical rib articulate with
The inferior costal demifacet of the thoracic vertebral body one segment superiorly
What does the inferior articular fact of typical ribs articulate with
Articulates with the superior costal demifacet on the thoracic vertebra of the same level
