2. Thoracic Wall
• Structure:
skin fascia muscle bone
blood vessels & nerves
• Functions:
1. protection of thoracic
viscera
2. provides the mechanical
function of breathing
3. Thoracic Cage
The bony part of thoracic wallThe bony part of thoracic wall
- 12 pairs of ribs & CC- 12 pairs of ribs & CC
- 12 thoracic vertebrae- 12 thoracic vertebrae
- Sternum- Sternum
4. Ribs
- Flat curved bones with high- Flat curved bones with high
resilienceresilience
- Form most of the thoracic cage- Form most of the thoracic cage
-3 types:3 types:
1. True (11. True (1stst
– 7– 7thth
))
2. False (82. False (8thth
– 10– 10thth
))
3. Floating (113. Floating (11thth
& 12& 12thth
))
5. Features of Typical Ribs
1. Head: wedge-shaped with 2 articular facets
2. Neck: connects the head with the body
3. Tubercle: articular &
non-articular parts
4. Shaft (Body): angle &
costal groove
6. Typical Ribs
33rdrd
– 9– 9thth
ribs are consideredribs are considered
typicaltypical
1.1. Articular facetsArticular facets
2.2. Crest of HeadCrest of Head
3.3. NeckNeck
4+5. Tubercle4+5. Tubercle
6. Angle6. Angle
7. Costal groove7. Costal groove
8. shaft8. shaft
7. Atypical Ribs
• 1st
rib
Flat, scalene tubercle & grooves for subclavian v.
• 2nd
rib
rough tuberosity for serratus anterior m.
• 10th
rib
one facet on the head
• 11th
& 12th
one facet on the head & no neck or tubercle
8. 1st
Rib
1.1. Flat ribFlat rib
2. Scalene Tubercle2. Scalene Tubercle
3. Grooves for3. Grooves for
subclavian vesselssubclavian vessels
4. One Facet on the4. One Facet on the
headhead
9. Clinical: Cervical Rib
• Extra rib arise from C7 vertebra
• Present in ∼1% of people
• Complications:
Causes pressure on nerves & arteries supplying the
upper limb
Tingling & numbness Partial paralysis
11. Rib Fractures
• Common chest injuries (middle ribs, 5-10)
• Mostly in weakest part (the angle)
• Present as a sever localized pain
• Complications: inj. to underlying structures
pneumothorax (air in pleural cavity)
14. Sternum
((G, Sternon: chest boneG, Sternon: chest bone ))
Flat, vertically elongated boneFlat, vertically elongated bone
that forms the middle anteriorthat forms the middle anterior
part of the thoracic cagepart of the thoracic cage
3 parts:3 parts:
ManubriumManubrium
BodyBody
Xiphoid processXiphoid process
16. Sternal Angle
Angle of louisAngle of louis
ManubriosternalManubriosternal
jointjoint
Easily palpatedEasily palpated
Opposite to T4-T5Opposite to T4-T5
discdisc
2nd costal cartilage:2nd costal cartilage:
Counting the ribs & intercostal spacesCounting the ribs & intercostal spaces
18. Openings of Thoracic Wall
•Boundaries of superior thoracicBoundaries of superior thoracic
opening:opening:
•Post: T1,Post: T1,
•On each side: 1On each side: 1stst
rib,rib,
• Ant: manubriumAnt: manubrium
•Contents of InletContents of Inlet
• Viscera : Tachea, oesophagusViscera : Tachea, oesophagus
• Large Vessels: Brachiocphalic arteryLarge Vessels: Brachiocphalic artery
Lf common caotid artLf common caotid art
•Small Vessels:Small Vessels:
Rt&Lt Int thorasic artRt&Lt Int thorasic art
Rt&Lt superior Intercosatal artRt&Lt superior Intercosatal art
• Nerves& muslesNerves& musles
19. Boundaries of inferiorBoundaries of inferior
thoracic openingthoracic opening /outlet/outlet::
• Posteriorly: T12,Posteriorly: T12,
• On each side: 7-10 CC,On each side: 7-10 CC,
• Anteriorly: xiphisternal jointAnteriorly: xiphisternal joint
20. Thoracic Outlet Syndrome
• On the superior thoracic opening (anatomical inlet)
• Compression of subclavian art. between the clavicle & 1st
rib
(Costoclavicular syndrome)
• Pale color & coldness on the skin of upper limb
• Diminished radial pulse
23. Intercostal Muscles
3 layers3 layers of m. that cover intercostal spacesof m. that cover intercostal spaces
From outside to inside:From outside to inside:
1. External intercostal m.:1. External intercostal m.:
runs downward toward sternum (runs downward toward sternum (your ant. pocketsyour ant. pockets))
replacedreplaced anteriorlyanteriorly by membraneby membrane
2. Internal intercostal m.:2. Internal intercostal m.:
runs downward toward VC (runs downward toward VC (your post. pocketsyour post. pockets))
replacedreplaced posteriorlyposteriorly by membraneby membrane
24. 3. Innermost intercostal & Transversus3. Innermost intercostal & Transversus
ThoracicThoracic
IIm:IIm:
on lateral sides onlyon lateral sides only
TTm:TTm:
4-5 slips of muscles4-5 slips of muscles
From post. surface of sternumFrom post. surface of sternum
To 2To 2ndnd
-6-6thth
costal cartilagescostal cartilages
Bld. Vessels & nerves run between:
Internal & innermost IMs