The Thorax Flashcards
What is the superior thoracic aperture
Opening at the top of the thoracic cavity
Connects neck to chest
What makes up the anterior wall of the thoracic cavity
Ribs, costal cartilages, intercostal muscles and sternum
What makes up the superior thoracic aperture
The first rib, T1 vertebral body and the sternum
What makes up the lateral walls of the thoracic cavity
Ribs and the intercostal muscles
What makes up the posterior wall of the thoracic cavity
Ribs, intercostal muscles and vertebra
What is the inferior thoracic aperture
The lower opening of the thorax
What structure separates the thorax from the abdomen
Diaphragm
What makes up the inferior thoracic aperture
Diaphragm
Where do the intercostal arteries arise from
Thoracic aorta and internal thoracic arteries
What arteries arise from the thoracic aorta and the internal thoracic arteries
Intercostal arteries
Where do the internal thoracic mammary arteries arise from
Subclavian artery
What arteries arise from the subclavian artery
Internal thoracic mammary arteries
Where does the intercostal nerve arise from
Anterior rami of the spinal nerve
What arises from the anterior rami of the spinal nerve
Intercostal nerve
Where do the intercostal artery, vein and nerve run
In the subcostal groove of the rib
What structures run in the subcostal groove of the rib
Intercostal artery, vein and nerve
What can the internal thoracic mammary artery be repurposed for
Coronary artery bypass graft
Breast reconstruction
What is the mediastinum
Region between left and right lung
What does the mediastinum contain
Most of the contents of the thorax apart from the two lungs
How is the mediastinum divided
Divided into 4 regions
Superior and inferior
Inferior divided into anterior middle and posterior
How is the superior and inferior mediastinum divided
Imaginary line between the angle of Louis and T4
What is the boundary for the anterior mediastinum
Everything anterior to the fibrous pericardium of the heart
What is the boundary for the middle mediastinum
Pericardium and the heart
What is the boundary for the posterior mediastinum
Everything posterior to the fibrous pericardium
What does the superior mediastinum contain
Major arteries- arch of the aorta, brachiocephalic, left common carotid, left subclavian
Major veins- right and left brachiocephalic veins, superior vena cava
Thymus
Oesophagus
Trachea
Phrenic nerve
Vagus nerve
Left recurrent laryngeal nerve
What nerve roots does the phrenic nerve originate from
C3,4 and 5
What is the function of the phrenic nerve
Motor supply to the diaphragm
Sensory supply to the pericardium, diaphragm and mediastinal pleura
What cranial nerve is the vagus nerve
Cranial nerve X
What is the name of cranial nerve X
Vagus nerve
Where does cranial nerve X originate from
Medulla
Where does the vagus nerve travel down from the medulla
Down the neck through the superior mediastinum and into posterior mediastinum
What nerve originates from the medulla and travels down the neck through the superior mediastinum and into the posterior mediastinum
Vagus nerve or cranial nerve X
What are the functions of the vagus nerve
Motor supply to muscles of pharynx and larynx
Sensory- visceral sensation to heart and abdominal visceral
Special sensory- taste sensation- epiglottis and root of the tongue
Autonomic- parasympathetic fibres innervate trachea, bronchi, GI tract and heart
What does the anterior mediastinum contain
Thymus gland
Internal thoracic mammary arteries
What part of the mediastinum would you find the thymus glands and the internal thoracic mammary arteries
Anterior mediastinum
What does the middle mediastinum contain
Phrenic nerves, pericardium, heart
Origin of major vessels- ascending aorta, pulmonary trunk and superior vena cava
Bifurcation of trachea at T4
What part of the mediastinum would you find the ascending aorta, pulmonary trunk, bifurcation of the trachea and the phrenic nerves
Middle mediastinum
What does the posterior mediastinum contain
Vascular structures
GI structures
Lymphatic structures
Nervous system structures
What vascular structures are found in the posterior mediastinum
Thoracic aorta
Azygous and hemi-azygous veins- drain thoracic walls and upper lumbar region- drains into superior vena cava
What GI structure is found in the posterior mediastinum
Oesophagus
What lymphatic structure is found in the posterior mediastinum
Thoracic duct
What nervous system structures are found in the posterior mediastinum
Sympathetic trunk- short pre-ganglionic neurones, synapse in either paravertebral chain or pre-vertebral ganglia
What is recurrent laryngeal nerve palsy
Laryngeal nerve branch of vagus nerve becomes damaged
Can be caused by tumour from lung cancer
Causes voice hoarseness and difficulty breathing
What is gastroparesis
Condition caused by dysfunction of vagus nerve
Leads to delayed stomach emptying, bloating abdominal pain, nausea and vomiting
Commonly caused by diabetes
What is boerhaave’s syndrome
Rupture of Oesophagus wall
Mostly due to iatrogenic causes - result of medical treatment or interventions- or excessive vomiting/ straining
100% mortality rate without surgical intervention- 30% with
Can lead to mediastinitis and sepsis
What is lymphadenopathy
Swelling/ enlargement of lymph nodes due to infection or cancer
What is lymphoedema
Swelling of body tissues due to blockage of lymphatic drainage
Can occur secondary to removal of lymph nodes in cancer treatment
In terms of the phrenic nerve why do patients sometimes feel shoulder tip pain if they have an ectopic pregnancy
Blood enters abdominal cavity due to pregnancy
Blood irritates diaphragm and stimulates phrenic nerve
Phrenic nerve controls diaphragm and has sensory fibres in shoulder region
So both areas stimulated
What is Gillian-Barre syndrome
Autoimmune condition
Attacks peripheral nervous system
Causes ascending paralysis
Can lead to breathing difficulties
