Thoracic Wall and Pectoral Region Flashcards
Inferior thoracic aperture
boundaries:
β 12th thoracic vertebra β 11th and 12th pair of ribs β Costal cartilages of ribs 7 th β 10th (costal margin) β Xiphisternal joint β Closed by the diaphragm
Superior thoracic aperture-Boundaries:
Body of 1st thoracic vertebra
β 1st ribs and their costal cartilages
β Jugular notch
Superior thoracic aperture-Structures passing through
Left Subclavian artery
β Subclavian (or SCV) vein
β Brachiocephalic trunk
Thoracic wall-Bones
Vertebrae, ribs, sternum
Thoracic wall-Muscles
Diaphragm, intercostal, pectoral, serratus
anterior, latissimus dorsi
Thoracic wall-Nerves and blood vessels
β Intercostal neurovascular bundle
Sternum-three portions:
β Manubrium
β Body
β Xiphoid process
Sternum-Articulates with:
β Clavicle
β Costal cartilages I-VII
Jugular notch
Small indentation on the superior
border of the manubrium
Manubriosternal joint
Anterior boundary of the transthoracic plane β Corresponds to: β’ T4/5 intervertebral disc β’ 2nd costal cartilage
Atypical ribs
(1, 2, 10, 11, 12)
Thoracic vertebrae
-Small heart shaped body
β’ Round vertebral foramen
β’ Downward slanting spinous process
β’ Two demifacets on body for articulation with the head of the rib
β’ A facet on the transverse process for articulation with the tubercle of the rib
COSTOVERTEBRAL Joints
Synovial joints between rib and
vertebrae
STERNOCOSTAL Joints
Synovial joints between costal
cartilage and sternum
(1st is fibrocartilaginous)
True ribs (1-7)
attach to sternum via
own costal cartilage
False ribs (8-10) -
attach to costal cartilage of
rib above
Floating ribs
- no attachment anteriorly
Intercostal muscles-Neurovascular bundle
β intercostal artery, vein, nerve
β between internal and innermost
-Innervation is segmental from intercostal nerves**
Intercostal muscles-Action:
Elevation and depression of ribs
and maintaining the intercostal space
during respiration
Intercostal muscles
- External intercostal-Fibers β down and medial
- Internal intercostal-Fibers β down and lateral
- Innermost intercostal-same as internal
Transversus thoracis muscle- loction
Radiates out from the
sternumβ