The document describes the anatomy of the thorax, including bony landmarks like the ribs and costal cartilages, as well as soft tissue landmarks like the nipple. It details the skeleton of the thorax, which forms an osseo-cartilaginous elastic cage. The superior and inferior apertures of the thorax are described, along with the structures that pass through each. The large and small openings in the diaphragm are listed. Applied anatomy concepts related to the thorax like cervical ribs and diaphragm function are also mentioned.

1. INTRODUCTION
TO THORAX

2. BONY LANDMARKS
1. Supra-sternal / Jugular notch
2. Sternal angle
3. Xiphi-sternal joint
4. Costal cartilages
5. Ribs
6. Thoracic vertebral spines

3. SOFT TISSUE LANDMARKS
1. Nipple
2. Apex beat
3. Trachea
4. Mid-clavicular line
5. Mid-axillary line
6. Scapular line

4. SKELETON OF THORAX
• Osseo-cartilaginous elastic cage.
Formation
• Anteriorly :
• Posteriorly :
• On each side :

8. SKELETON OF THORAX
Shape
Transverse section :
• In adults – reniform
• In Infants – circular
• In quadrapeds -

10. SUPERIOR APERTURE / INLET

11. SUPERIOR APERTURE / INLET
• It is the narrow upper part of thorax which is
continuous with the neck.
• Kidney shaped
• Transverse diameter- 10-12.5 cm
• Ant-post diameter – 5 cm.

12. SUPERIOR APERTURE / INLET
• Boundaries :
• Anterior –
• Posterior –
• On each side -

13. SUPRA-PLEURAL MEMBRANE

14. SUPRA-PLEURAL MEMBRANE

15. STRUCTURES PASSING THROUGH THE
INLET
• Viscera
• Large vessels
• Smaller vessels
• Nerves
• Muscles

17. INFERIOR APERTURE / OUTLET
• Broad end of thorax surrounded by upper part
of abdominal cavity but separated from it by
the diaphragm.

18. INFERIOR APERTURE / OUTLET
• Boundaries :
• Anteriorly –
– Infrasternal angle between two costal margins
• Posteriorly –
– Inferior surface of the body of 12th Thoracic
vertebra
• On each side –
– Costal margins formed by cartilages of 7th to 12th
ribs.

19. INFERIOR APERTURE / OUTLET
• The outlet is closed by a large musculo-
tendinous partition – Diaphragm – Thoraco-
abdominal diaphragm.
• Large openings : three
• Small openings : numerous

20. LARGE OPENINGS
1. Inferior Venacava – T8 –Central tendon –
quadrilateral – IVC, Right phrenic nerve,
Lymphatics of liver.
2. Oesophageal opening – T10, Right crus –
elliptical, oesophagus, both vagal trunks, left
gastric vessels.
3. Aortic opening – T12, rounded, behind Median
arcuate ligament, Aorta, thoracic duct,
Azygous vein.

22. SMALL OPENINGS
Superior Epigastric artery Space of Larry Between the slip of
xiphoid process and 7th
costal cartilaginous slip of
diaphragm.
Musculo-phrenic artery At the level of 9th costal
cartilage
Lower 5 intercostal vessels
and nerves
Pass between costal
margins of diaphragm and
Transversus abdominis.
Subcostal vessels and
nerves
Behind Lateral Arcuate
ligament
Sympathetic trunk Behind Medial Arcuate
ligament
Greater and lesser
splanchnic nerves
Pierce each crus
Left phrenic nerve Pierces left cupola

24. APPLIED ANATOMY
1. Cervical rib
2. Coarctation or narrowing of aorta
3. Thoracic inlet syndrome
4. Diaphragm
5. Hiccups
6. Rib fracture