Thorax, Snell Flashcards
3 parts of sternum
1) Manubrium
2) Body
3) Xiphoid process
Manubrium articulates with
1) Body of sternum
2) Clavicles
3) First costal cartilage
4) Upper part of 2nd costal cartilage
Landmark formed by articulation of manubrium with body of sternum
Sternal angle of Louis
5 structures at the level of sternal angle of Louis
1) 2nd costal cartilage
2) Junction of superior and inferior mediastinum
3) Bifurcation of trachea
4) Junction of ascending aorta and aortic arch and aortic arch and descending aorta
5) IV disc between T4 and T5
Body of sternum articulates with on each side with
2nd to 7th costal cartilages
T/F Xiphoid process is ossified at birth
No, plate of cartilage that becomes ossified at proximal end during adult life
T/F No ribs or costal cartilages are attached to the xiphoid process
T
T/F Sternum possesses red hemopoietic marrow throughout life
T
Ribs, #
12
Categories of ribs
1) True
2) False
3) Floating
True ribs
Attached to the sternum by their costal cartilages (1st-7th)
False ribs
Attached anteriorly to each other and to the 7th rib by their costal cartilages and small synovial joints (8th-10th)
Floating ribs
No anterior attachment (11th-12th)
Atypical rib
1st rib
Superior vs inferior: Costal groove
Inferior
Costal groove accomodates
Intercostal vessels and nerves
Typical rib: Parts
1) Head
2) Neck
3) Tubercle
4) Shaft
5) Angle
Head of rib: How many facets
2
Head of rib: Superior facet articulates with
Vertebra immediately above it
Head of rib: Inferior facet articulates with
Numerically corresponding vertebral body
Tubercle of rib: How many facets
1
Tubercle of rib: Facet articulates with
Transverse process of the numerically corresponding vertebra
Part of rib where the shaft bends forward sharply
Angle
Important structures related to the first rib (2)
1) Brachial plexus
2) Subclavian artery and vein
T/F The first rib is flattened anteroposteriorly
F, superoinferiorly
First rib: Muscle attached to its upper surface and inner border
Scalenus anterior
Crosses first rib anterior to the scalenus anterior
Subclavian vein
Lie in contact with 1st rib posterior to the scalenus anterior attachment
1) Subclavian artery
2) Brachial plexus
A cervical rib occurs in ~ ___% of persons
0.5
Cervical rib: Arises from
Transverse process of C7
Cervical rib: Possible anterior attachments
1) Free
2) Connected to first rib by fibrous band
3) Articulate with 1st rib
Thoracic outlet syndrome is brought about by compression of what structures by the cervical rib
1) Brachial plexus
2) Subclavian artery
T/F Costal cartilages of eighth, ninth, and tenth ribs connect to the cartilage immediately above them
T
T/F 11th and 12th ribs do not have costal cartilages
F, cartilages of the eleventh and twelfth ribs end in the abdominal musculature
Rib #s: Head articulates by a synovial joint with the corresponding vertebral body and that of the vertebra above it
2nd-9th
Rib #s: Heads have a simple synovial joint with the corresponding vertebral body
1st, 10th-12th
Type of joint: Manubriosternal joint
Cartilaginous
Type of joint: Xiphisternal joint
Cartilaginous
Type of joint: Costovertebral joint
Synovial
Articulation of rib tubercle with transverse process of corresponding vertebra is absent in which ribs
11th-12th
Type of joint: Costochondral
Cartilaginous
Movement in the costochondral joint
NONE
Type of joint: Articulation of first costal cartilage with manubrium
Cartilaginous
Articulation of first costal cartilage with manubrium: Movement
NONE
Type of joint: Articulation of second to the seventh costal cartilages articulate with the lateral border of the sternum
Synovial joints
Type of joint: Articulation of sixth, seventh, eighth, ninth, and tenth costal cartilages with one another
Small synovial joints
Movement that rotates the neck of rib around its own axis
Respiration
Brachial plexus, subclavian artery, and subclavian vein can be compressed between which bones
1) First rib
2) Clavicle
Muscles of respiration within intercostal spaces
1) External intercostal
2) Internal intercostal
3) Innermost intercostal
Thoracic muscles are lined internally by
Endothoracic fascia and parietal pleura
Intercostal nerves and blood vessels run between what muscles
1) Internal intercostal muscles
2) Innermost intercostal muscles
Intercostal nerves and blood vessels: Arrangement from superior to inferior
VAN
Intercostal vein
Intercostal artery
Intercostal nerve
Needle thoracostomy: Indications
1) Tension pneumothorax
2) Large hemothorax
Most important muscle of respiration
Diaphragm
Diaphragm: Insertion
Central tendon
Diaphragm: Nerve supply
Phrenic
Raise ribs during inspiration and lower ribs during expiration
External intercostals