Thoracic inlet & outlet

Major openings
Caval opening
Oesophageal opening Aortic opening

1. 2 Learning objectives At the end of session students should be able to • Describe the thoracic cage and its boundaries, thoracic Inlet and outlet. • Describe the position & component of muscular & tendinous part of diaphragm • Describe the attachments of diaphragm along with its blood supply and nerve supply • Describe the openings present in the diaphragm and their respective levels • Enumerate the structures passing through the openings and piercing the diaphragm. • List the functions of diaphragm • Enumerate the conditions related to damage to Phrenic Nerve • Describe the main features of these condition

2. 3

3. Thorax - boundaries 4

4. Superior Thoracic Aperture 6

5. Plane of Inlet 7 4 5 °

6. Suprapleural membrane/ Sibson’s fascia 8

7. Suprapleural membrane: Relations 9

8. Trachea Oesophagus Thoracic duct Apices of the lungs Nerves Phrenic nerve Vagus nerve Recurrent laryngeal nerves Sympathetic trunks Vessels Arteries left and right  common carotid arteries left  Subclavian arteries Veins internal jugular veins brachiocephalic veins subclavian veins Lymph nodes  and  Lymphatic  vessels Structures that pass through the superior thoracic aperture include :

9. Inf thoracic aperture-Diaphragm- ant view 12

10. Thoracic skeleton ant view 13

11. 12 Thoracic skeleton post view

12. Typical rib 15

13. Atypical ribs 16

14. Thoracic vertebrae 17

15. Sternum and Joints 18

16. 19 Intercostal muscles External Internal I nn e r m ost    Subcostalis Intercostalis intima Sternocostalis {transversus thoracis }

17. Intercostal muscles 20

18. External and internal intercostal muscles 21

19. External and internal intercostal muscles 22

20. Cervical Rib Syndrome 43

21. Diaphragm Greek, from dia 'through, apart' + phragma 'a fence'. Fibro-muscular sheet Separates the thoracic cavity from the abdominal cavity Performs an important function in respiration.

22. Origin 3 Parts:- Sternal Costal l u mbar

23. Direction of muscle fibres Upwards & inwards Right and left dome

24. Nerve Supply Motor – Phrenic nerve(C3,4,5) Sensory – central part- phrenic nerve peripheral part- lower six thoracic nerve

25. Blood Supply Musculophrenic artery Superior phrenic arteries Lower 5 intercostal arteries + subcostal artey Inferior phrenic artery

26. Actions 1. Principal muscle of Inspiration.

27. Helps in expulsive acts- Sneezing, Coughing, Laughing, Crying, Vomiting Micturition, Defaecation Or Parturation . May have sphincteric action on the lower oesophagus.

28. Position of Diaphragm 3 Factors :- The elastic recoil of Lung The pressure exerted by abdominal viscera The muscles of abdominal wall Highest- in supine position Lowest- in sitting Intermediate- in standing

29. Relations Superiorly- pleurae pe r i c a r d i um Inferiorly - pe r i t o n eum liver fundus of stomach spleen kidneys suprarenal

30. Openings Major openings Caval opening Oesophageal opening Aortic opening

31. Minor openings aperture in right crus lesser aperture in left crus under the medial lumbocostal arches under the lateral lumbocostal arches foramina of Morgagni

32. Development The Diaphragm 'develops from the following sources. Septum transversum Pleuroperitoneal membranes Lateral thoracic wall Dorsal mesentery of oesophagus

33. Applied Anatomy 1. Hiccough- a)peripheral b)central Shoulder tip pain Unilateral paralysis of Diaphragm Eventration Diaphragmatic hernia – a) Congenital b) Acquired

34. Congenital Hernia Morgagni hernia or Retrosternal hernia Bochdalek hernia or Posterolateral Central hernia

35. e) Congenital hiatal hernia d) Posterior hernia

36. Bochdalek hernia

37. Acquired Hernia Traumatic hernia Acquired hiatal hernia