Diaphragm and Pericardium Flashcards
Describe diaphragm and its attachments and it’s functions
What does its contraction lead to
- skeletal muscle that partitions thorax and abdomen
- arises for peripheral of body wall and inserts into central tendon
- primary thoracic muscle of respiration
- it’s contractions leads to increase in vertical volume of thoracic cavity during inspiration
List the diaphragm openings
Structures that pass through
Relation to diaphragm of structures
- T8 Caval opening, in central tendon : inferior vena cava, right phrenic nerve
- T10 esophagus opening, in diaphragm muscle fibers : esophagus, vagus nerves
- T12 aortic opening, behind diaphragm: aorta, azygos veins, thoracic duct , hemizygos veins
Where does heart lie on diaphragm
Describe sterna, coastal and lumbar part of diaphragm
- on central tendon , central aponeurosis tendon
- 2 slips away from xithoid process, sternocostal hiatus for internal thoracic artery and lymph vessels
- internal surface of inf 6 ribs and interdigitate with transversus abdominis
- has 2 crura. Blends with anterior longitudinal ligaments and arcuate ligaments. Either side of aorta
Describe crura and arcuate ligaments of diaphragm
What they cover
Their attachments
- right crus surrounds esophageal hiatus. Broader and longer than left
- median arcuate over ant aorta. Unites medial sides of 2 crura
- medial lumbosacral arch arcuate ligament : ant layer of thoracolumbar fascia thickening to transverse process of L1 over psoas major
- later lumbosacral arch arcuate ligament over quadratus lumborum from L1 to T12 transverse process. Left kidney thin
List structures
Behind
Lateral
Anterior
To diaphragm
- splanchnic nerves and sympathetic trunks
- lower 6 intercostal vessels and nerves
- lymphatics and superior epi gastric vessels
Describe innervation of diaphragm
What does the phrenic nerve do
- motor phrenic C3-5
- central sensory is C3-5
- periphery sensory is intercostal T5-T11 and subcostal T12
- keeps diaphragm alive. Supply mediastinum and diaphragm pleura , periosteum and skin over shoulder and pericardium ( fibrous and parietal )
List arterial and venous drainage of diaphragm
- superior phrenic nerve. Musculophrenic. Pericardiophrenic.
/ the last 2 accompany phrenic nerves - inferior phrenic vein. Musculophrenic and pericardiophrenic nerves
Describe lymphatic drainage of diaphragm
What is pain over shoulder
- diaphragmatic LN
- posterior mediastinal LN
- superior lumbar LN
- pain of pericardium as they have similar roots from phrenic nerve
What is the pericardium
It’s attachments
- double elapsed fibroserous sac enclosing the heart and roots of its great vessels.
- sternum post by ligaments
- adventitia of great vessels
- central tendon of diaphragm
Describe fibrous pericardium and it’s functions
It’s extensions
- superficial part of sac. CT collagen dense irregular
- protects heart and limits distention
- prevents overfilling with blood
- extensions to aorta, SVC, R and L pulm art and pulm veins
Describe movement of internal thoracic artery
List the 3 parts of parietal pleural
- originates from subclavian arteries.
- moves down and at T8/9 divides into
1 superior epi gastric vessels ( more medial )
2 musculophrenic arteries ( lateral and longer )
1 costal
2 mediastinal
3 diaphragmatic
Describe movement of vagal recurrent nerves
Nerve supply of pericardium
1 right recurrent laryngeal nerve goes under subclavian artery and upwards
2 left under arch of aorta and upwards
- vagus and phrenic nerves
Describe serous and its layers
Describe parietal layer. It’s movements and what it covers
- double layered ( parietal and visceral - inner layer )
- deep to fibrous pericardium and have pericardial cavity in between
- lines internal FP. Turns inferior and continues over heart as visceral.
- ant superior surrounds aorta and p trunk
- post surrounds SVC and IVC and p veins.
Describe ligamentum arteriosum
- a ligament which joins inferior surface of arch of aorta to superior surface of bifurcating p trunk
Describe blood supply and venous drainage of pericardium
- internal thoracic. Musculophrenic. Pericardiophrenic. Thoracic aorta. Inferior phrenic arteries.
- azygos. Internal thoracic. Inferior phrenic veins.
