Anatomy&Histology Flashcards
INSPIRATORY MUSCLES Rib elevators:
external intercostal muscles
Muscles attaching cervical vertebrae to first & second rib:
scalene muscles
Muscles attaching thoracic cage to upper limb
pectoralis major
ORIGIN OF DIAPHRAGM Costal
lower 6 costal cartilages
ORIGIN OF DIAPHRAGM Sternal
xiphoid process of sternum
ORIGIN OF DIAPHRAGM Vertebral
upper 3 lumbar vertebrae
(right & left crus + arcuate ligaments)
DIAPHRAGM nerve supply
phrenic nerve (C3,4,5),
DIAPHRAGM action
contraction (descent) of diaphragm increase vertical diameter of thoracic cavity
EXTERNAL INTERCOSTAL Attachments:
from lower border of rib above to upper border of rib below
EXTERNAL INTERCOSTAL Nerve supply:
intercostal nerves
EXTERNAL INTERCOSTAL Action:
rib elevators (inspiratory)
EXTERNAL INTERCOSTAL Direction of fibers:
downward & medially
SCALENE MUSCLES
Origin:
Insertion :
Action:
cervical vertebrae
1st & 2nd ribs
elevates 1st & 2nd ribs (inspiratory)
PECTORALIS MAJOR
Origin:
Insertion:
Action:
Origin: sternum + costal cartilages
Insertion: humerus
Action: increases antero-posterior diameter of thoracic cavity, when arm is fixed (inspiratory)
EXPIRATORY MUSCLES Rib depressors
Internal intercostal
Innermost intercostal
Subcostals
Transversus thoracis
EXPIRATORY MUSCLES Anterior abdominal wall muscles:
External oblique
Internal oblique
Transversus abdominis
Rectus abdominis
RIB DEPRESSORS: REST OF INTERCOSTAL MUSCLES
Direction:
Nerve supply:
Direction: upward & medially
Nerve supply: intercostal nerves (ventral rami of T1-T11)
External oblique (outer layer) Direction:
Direction: downward & medially
Internal oblique (middle layer) Direction:
Direction: upward & medially
Transversus abdominis (inner layer) Direction:
Direction: transverse
Rectus abdominis Direction:
Direction: vertical
VESTIBULE Lining
Lining: is lined with thin skin.
1- Epidermis: (Keratinized stratified Squamous epithelium).
2- Dermis.
VESTIBULE Contents:
Contents:
1- Vibrissae: stiff hairs.
2- Sebaceous glands.
3- Sweat glands.
VESTIBULE Wall:
Wall:
1- Hyaline cartilage.
2- Cancellous (spongy) bone.