Thoracic Cage & Wall Flashcards
Give reason: the thoracic inlet is oblique
Due to obliquity of 1st rib
Describe the structure of intervertebral foramen and structures passing through it.
Formed from articulation of seperior and infecrior notches (adjacent) of pedicle.
Spinal nerves and vessels pass through it
Contents of vertebral foramen
Spinal cord and meninges
Compare articular processes of thoracic vertebra.
Superior: project upwards, articular surface directed backwards.
Inferior: project downwards, articular surface directed forwards.
Type of joint between costal facets and heads of ribs.
Plane synovial
Type of joint between transverse process and tubercle of ribs.
Plane synovial joint
Vertebrae where their transverse process lacks facets.
11th & 12th
Each typical vertebra articulates with ……. & …….. .
The corresponding rib and the one below.
The thoracic vertebra resembling cervical v having complete superior facet.
First T.V.
Vertebra identical to typical except it lacks inferior demifacet
9th T.V.
Type of joints between articular processes.
Plane synovial joint
Lamina connected by ……. , spines connected by ……., their tips connected by …….. & transverse processes connected by …… .
Ligamentum flavum
Interspinous ligaments
Supraspinous liagment
Intertransverse ligament
True ribs are …..
False ribs are ……
Floating ribs are …….
1st-7th
8th-12th
11&12th
The free anterior end of floating ribs is
Embedded in the muscles of the abdominal wall
The crest of head of rib is connected to the IVD by ……. . The costo-vertebral joints are ……. .
Articular ligaments
Plane synovial
Structure attached to lateral part of tubercle of rib.
Lateral costo-transverse ligament
Site and contents of costal groove
Inner surface of rib, it contains vein, artery & nerve.
Neck of first rib is anteriorly related to ..
- Sympathetic chain with stellate ganglion
- Superior intercostal artery
- Ventral ramus of 1st thoracic nerve
Structures attached to inner surface of first rib
Scalenus anterior muscle
Suprapleural membrane
Lateral border of 1st rib gives attachment to
Serratus anterior
Mention structure present in grooves of upper surface of 1st rib
Anterior groove: subclavian vein
P. groove: subclavian artery + lower trunk of brachial plexus
Anterior to groove of subclavian vein there is ….. & ….. .
Posterior to groove of subclavian artery is …
- Costo-clavicular ligament, subclavius muscle
2. Scalenus medius muscle
Dagger-like rib
12th rib
Describe the clincal significance of lumbar rib
- Confuse the identification of vertebral levels
- Interpreted as fractured transverse process of L1 vertebra
Cervical rib may lead to ….
Lower trunk lesion
Type of the following joints
- 1st costal cartilage and manubrium
- 2nd costal cartilage and manubrium
- primary cartilagenous joint
- synovial joint
Type of the following joints:
- sternoclavicular
- manubrio-sternal
- synovial saddle
- secondary cartilagenous
The superior boder of manubrium lies …..
Between T2 & T3
The sternal angle lies opposite …
IVD between T4 & T5
Importance of sternal angle.
- Counting ribs in a living subject
- indicated level of tracheal bifurcation and termination and beginning of the large vessels
Muscles origination from anterior surface of manubrium
Sternocleidomastoid & pectoralis major
Posterior surface of manubrium gives origin to
Sternohyoid & sternothyroid
Posterior surface of manubrium forms anterior boundary of …… mediastinum
Superior
Relations of posterior surface of manubrium
- Arch if aorta
- brachiocephalic, left common carotid & left subclavian arteries
- pleurae & lungs
Type of manubrio-sternal & xiphisternal joints
Secondary cartilagenous
Mention number and origin of sternebrae
3
Composite development of the sternum
Mmnetion muscle originating from anterior surface of sternal body
Pectoralis major
Posterior surface of sternal body forms boundary of ….. mediastinum
Anterior
Muscles arising from posterior surface of sternal body
Sternocostalis
Level at which sternal body is related to the heart
4th costal cartilage
2nd-7th sterno-costal joints are …
Synovial joints
Level of xiphisternal joint
IVD between T9 & T10
Mention supporting ligaments of following joints:
- Sterno-costal
- Costotransverse
- Intra-articular ligament
2. costotransverse ligament, lateral costotransverse ligament, superior costotransverse ligament
What occurs when the upper 6 ribs rotate?
Result in elevation and depression movements of the sternal ends of the ribs and the sternum causing pump-handle movements.
What happens with the gliding movement of 7th-10th ribs?
Elevation and depression of lateral-most proportions of these ribs in the transverse plane causing bucket-handle movement.
Type of costochondral joint & first sternocostal
Primary cartilagenous
Type of joint between vertebral body and head of ribs 2nd to 9th
Synovial joint
6th, 7th, 8th, 9th & 10th costal cartilages articulate by
Small synovial joints
Muscles connecting ribs to vertebra
Levatores costarum
Serratus posterior superior
Serratus posterior inferior
Extent of external intercostal
Tubercle of ribs post. to costochondral junction ant.
Extent of inetrnal intercostal
From the sternum infront to thr angle of the rib behind
Extent of innermost intecostal
Middle 2/4 of the intercostal space
Internal & external relarions of innermost intercostal
I: Endothoracic fascia, parietal pleura
E: intercostal nerves and vessels
The subcostales are well developend in ….. part of the thorax.
Lower & posterior
Describe attachment and direction of transvesus thoracis muscle
Arise from lower half of posterior surface of the body of sternum to be inserted by 5 slips in costal cartilages 2nd to 6th
Upwards & laterally
Mention the muscles of thorax corresponding to transversus abdominis
Innermost intercostals, subcostales & sternocostales
Nerve supply of muscles of thorax
Intercostal nerves
Mention action of the following muscles:
- External intercostals
- Internal and innermost
- Subcostales
- Sternocostales
- Inspiration (elevators)
- Expiration (depressors)
- Depresses the ribs
- Draws down costal cartilages
Describe main role of thoracic muscles
Forced respiration
Support contents of the intercostal spaces
Branches of typical intercostal nerves
- Rami communicantes
- Muscular branches
- Collateral branches
- Pleural sensory
- Lateral cutaneous (ant & post)
- Anterior cutaneous (med & lat)
The larger branch of first intercostal shares in …… , unlike typical intercostals it doesn’t give …. .
- Brachial plexus
- No lateral cutaneous branch
The larger branch of first intercostal shares in …… , unlike typical intercostals it doesn’t give …. .
- Brachial plexus
- No lateral cutaneous branch
Mention the other name of 2nd intercostal nerve & area supplied by it.
Intercostobrachial nerve
The skin of the floor of axilla, upper part of medial side of arm
The lower 5 intercostal nerves are atypical because ….
They pass between the costal slips of diaphragm
Intercostal spaces where anterior int. arteries are absent and why
10th & 11th
Because they are incomplete anteriorly
The 7th, 8th & 9th anterior intercostal arties are branches of ….
Musculophrenic artery
The anterior intercostal arteies end by
Anastomosing with post. int. artery & its collateral branch
Describe the origin of posterior intercostal arteries
1st & 2nd from superior interscostal which is a brach of costcervical (branch of 2nd part of subclavian)
3rd to 11th are branches of descending aorta
The landmark at which the posterior intercostal artery passes between internal and innermost muscles & branch originating at that site.
Costal angle, collateral branch
Branches of posterior intercostal arteries
- Dorsal branch
- Collateral branch
- Muscular branches
- Mammary branches
- Lateral cutaneous
- Right bronchial artery
Structures supplied by dorsal branch of posterior intercostal
Spinal cord, vertebral column, muscles & skin of the back.
Mammary branches arise from …… spaces
2nd, 3rd & 4th
Right bronchial artery arises from
Right 3rd posterior
The origin and termination of internal thoracic artery
O: 1st part of subclavian artery
T: 6th intercostal space dividea into musculophrenic & superior epigastric arteries
Mention branches of internal thoracic artery
- Pericardiophrenic
- Pericardial
- Anterior intercostal
- Perforating branches
- Musculophrenic
- Superior epigastric
Pericardiophrenic artery supplies
Diaphragm, pericardium, pleura
Perforating branches which supply mammary glands are found in…… enlarge during …. .
- 2nd, 3rd & 4th intercostal spaces
- lactation
Describe course of superior epigastric artery.
Descends between costal and sternals origins of diaphragm, enters rectus sheath, supplies rectus abdominis, ends by anastomosing with inferior epigastric artery
Venae comitantes of musculophrenic artery drain …. spaces
7th 8th 9th
3rd-6th spaces venous drainage is
Venae comitantes of internal thoracic artery
Internal thoracic vein forms at level of …. by union of …..
3rd costal cartilage
2 venase comitantes of internal thoracic artery
Describe venous drainage of posterior intercostal vein on the right
1st right brachiocephalic
2nd&3rd superior intercostal–> arch of azygos
4th-11th azygos
Describe venous drainage of posterior intercostal vein on the left
1st, left brachiocephalic
2nd&3rd form left superior intercostal which drain into left brachiocephalic
4th-8th end in superior hemiazgos
9th-11th end in inferior hemisazygos
The sup hemiazygos crosses at the level of …. while the inf hemiazygos crosses at the level of ….
7th thoracic vertebra
8th thoracic vertebra
Venae cominates of internal thoracic artery begin at level of …. by union of ……
6th intercostal space
Venae comitantes of musculophrenic & superior epigastric arteries
Internal thoracic vein drains into
Brachiocephalic vein
Describe origin of diaphragm
- sternal origin, 2 slips from xiphoid process
- costal origin, lower 6 costal cartilages and adjoining ribs
- lumbar origin, by 2 crura & 2 aponeurotic arches (lateral & medial arcuate ligaments)
Right crus arises from ….. , while left crus arises from …. .
- upper 3 lumbar v.+IVDs
- upper 2 lumbar v.+ IVDs
….. fibers of right crus embrace the esophagus
Medial
Level of median arcutae liagment
IVD between T12 & L1, connecting the medial tendinous margins of the crura.
Medial arcuate ligament covers ……., medially it is ……., laterally attached to …… .
- upper part of psoas major
- Continuous with lateral margin of corresponding crus.
- tranverse process of L1
Lateral arcuate ligament covers ……., medially attached to ……., laterally attached to …… .
- Upper part of quadratus lumboru
- transverse process of L1
- lower margin of 12th rib
3 leaflets if central tendon are ….. .
2 lateral & one middle
Median part of central tendon is related to
Pericardium and the heart
Structures related to left cupola but not the right
Fundus of the stomach & spleen
Give reason: right cupola is higher than left cupola
Due to upward bulge of right lobe of liver
Aortic opening at level of ……, structures passing through it are ….. .
T12 median plane
Aorta, thoracic duct & azygos vein
Oesophageal opening at level of ……, structures passing through it are ….. .
T10, one inch to the left
Oesophagus, gastric nerves & oesophageal branches of left gastric vessels
Caval opening at level of ……, structures passing through it are ….. .
T8, one inch to the right within central tendon
IVC, branches of right phrenic n, lymph vessels
Give reason: the IVC is always patent
Because the central tendon is adherent to the wall of IVC
Artery passing between sternal & costal origins of diaphragm
Superior epigastric artery
Level at which the musculophrenic artery pierces the diaphragm
9th costal cartilage
Lower 5 intercostal nerves pass through
2 slips of costal origin
Structure behind medial & lateral arcuate ligaments
M: psoas major & sympathetic trunk
L: quadratus lumorum & subcostal nerves & vessels
Structures oassing through minute opening in crura
- Greater & lesser splanchnic nerves via 2 openings in each crus.
- Hemiazygos vein (left crus)
Arterial supply of diaphragm
- pericardiophrenic
- inferior phrenic
- musculophrenic
- twigs from 3 posterior intercostal arteries
- twigs from descending aorta
Forced expulsive acts of diaphragm
Coughing, vomiting, defecation, urination & parturition.
Muscles fixing first rib during quiet inspiration
Scalene muscles
During foced inspiration, ….. & ….. elevate 1st rib. While ….. acts on manubrium & clavicle.
- scalenus anterior & medius
- sternocleidomastoid
During forced inspiration, the scapulae are fixed by …,…&… . So…..&….can pull the ribs.
- Trapezius, levator scapulae & rhomboid muscles.
- Serratus ant & pectoralis major
….. fixes 12th rib in forced inspiration.
Quadratus lumborum
Mention factors of passivity of quiet expiration
Elastic recoil of the lungs
Relaxation of the intercostal musckes & diaphragm
Forced expiration is done by…&…. .
Muscles of ant abd wall + latissimus dorsi
3rd-6th spaces anteriorly venous drainage is
Venae comitantes of internal thoracic artery
