1. Thoracic wall
-Skin
-Superficial fascia
-deep fascia

2. Muscles of respiration:
It includes muscles which are used in ordinary respiratiratory effort
This group includes 3 groups of muscles:
1- 3 muscles which connect vertebral column to the ribs
-Serratus posterior superior
-Serratus posterior inferior
-Levator costorum
2- 3 groups of muscles which connect adjacent ribs:
-External intercostal muscles (11 pairs)
-Internal intercostal muscles (11 pairs)
-Innermost intercostal
3- The muscle which fill-in the thoracic outlet:
the diaphragm which forms the thoraco-abdominal partition

3. 3 2 1 Intercostal muscles: 1- External intercostal muscle:
Origin, insertion, direction
2- Internal intercostal muscle:
3- Innermost intercostal muscle + transversus thoracic
Nerve supply and action 3 2 1

4. Respiratory Movement:
A- Quite inspiration:
During inspiration, movements of thoracic wall and diaphragm result in an increase in
all diameters of the thorax:
1- Vertical diameter:
It is increased by contraction (descent) of the diaphragm
2- Transverse diameter:
Bucket-handle movements
3- Anteroposterior diameter:
Pump- handle movements
B- Forced inspiration:
more muscles are called in action; as muscles of head and neck and upper limb
C- Quite expiration:
elastic recoil
D- Forced expiration:
forcible contraction of muscles of anterior abdominal wall

5. VAN Intercostal nerves: .They are the ventral rami of thoracic nerves
.They are 11 pairs + subcostal nerves
.3- 6 are called typical intercostal nerves
. First, second and lower 5 intercostals are atypical intercostal nerves
VAN

6. VAN Intercostal arteries: Anterior intercostal arteries:
-2 in each space except lower 2 spaces
- They are branches of internal thoracic artery and musculophrenic artery
Posterior intercostal arteries:
- One in each space (11 in No)
- They are branches of thoracic Aorta and costocervical trunk
Thoracic Aorta
VAN
Internal thoracic artery

7. Interernal mammary artery:
Originates from the 1st part of subclavian artery
Terminates at the 6th CC and gives musculophrenic and superior epigastric arteries

9. VAN Intercostal veins:
Anterior intercostal veins -----internal thoracic vein
Posterior intercostal veins:
Rt-----azygos vein
Lt----hemiazygos vein superior vena cava
Hemiazygos vein
Azygos vein
VAN