Ribs and Thoracic Wall Flashcards
What are the 3 types of chest abnormalities?
Pectus Carinatum
Pectus Excavatum
Barrel Chest
What is the origin , insertion, action, and bloody supply of the External intercostals?
Origin: inferior border of ribs
Insertion: Superior border of rib below
Muscle fibers run infero-anteriorly
Action: Elevates ribs (inspiration)
Innervation: Intercostal nerve (ventral rami of thoracic spinal nerve)
Blood supply: Intercostal artery, vein
What are the 3 types of Intercostal muscles?
External, Internal , Innermost
What is the origin , insertion, action, and bloody supply of the Internal intercostals?
Origin: inferior border of ribs
Insertion: Superior border of rib below
Muscle fibers run infero-posteriorly
Action: Depresses ribs (expiration)
Innervation: Intercostal nerve
What is the origin , insertion, action, and bloody supply of the Innermost intercostals?
Same as internal
What is the job of the Intercostal Muscles?
support the intercostal space and stiffen the rib cage so that more powerful muscles of respiration (like the diaphragm) can act effectively
What are the two movements of the thoracic wall?
Bucket handle and Pump Handle
What is the origin , insertion, action, and nerve supply of the Transversus Thoracis?
Origin: Posterior surface of lower sternum
Insertion: Internal surface of costal cartilages 2-6
action: weakly depresses ribs
What is the origin , insertion, action, and nerve supply of the subcostal?
Origin: Internal Surface of the lower ribs near their angles
Insertion: Superior borders of 2nd or 3rd ribs below
Innervation : Intercostal nerve
action: probally act in same manner as internal intercostal muscles
What is the origin , insertion, action, and nerve supply of the Levastores Costarum?
Origin: Transverse process of t7-t11
Insertion: Subjacent ribs between tubercle and angle
Innervation :Posterior Rami of C8-T11 nerves
action: Elevate ribs
What is the origin , insertion, action, and nerve supply of the Serratus posterior superior?
Origin: Nuchal ligament spinous processes of C7-T3 vertebrae
Insertion: Superior borders of 2nd and 4th ribs
Innervation : 2nd and 5th intercostal nerves
action: Elevate ribs
What is the origin , insertion, action, and nerve supply of the Serratus posterior inferior?
Origin: spinous processes of T11-L2 vertebrae
Insertion: Inferior Borders of 2nd-4th ribs
Innervation : 9th and 11th intercostal nerves
action: depress ribs
What is the origin , insertion, action, and nerve supply of the Pectoralis Major?
Origin: Clavicular head- anterior surface of medial half of clavicle
sternocostal head-anterior surface of sternum, superior six costal cartilages, aponeurosis of external oblique muscles
Lateral attatchment:Lateral lip of intertubercular groove of humerus
Innervation : Lateral and Medial Pectoral nerves;Clavicular head (C5,C6), Sternocostal head (C7,C8,T1)
action: abducts and medially rotates humerus: draws scapula anteriorly and inferiorly acting alone, clavicular head flexes humerus and sternocostal head extends it from the flexed position
Note the fibers of the pec major spiral before reaching insertion, lowest fibers insert highest up
What is the origin , insertion, action, and nerve supply of the Pectoralis Minor?
Origin: 3rd and 5th ribs near their costal cartilages
Lateral attatchment :Medial border and superior surface of coracoid process of scapula
Innervation : Medial pectoral nerve
action: stabilizes scapula by drawing inferiorly and anteriorly against thoracic wall
Where are the Mammary glands located ?
On the surface of the deep fascia on the pectoralis major in females
