Thoracic Wall Flashcards
What are the 3 main functions of the thorax?
- protection: heart and vessels, lungs, major airways, stomach, spleen and kidneys
- respiration: resists negative intra-thoracic pressure, works with abdominal muscles when breathing
- movement: provides attachment for muscles
What are the properties of the thorax?
- connects upper limb, abdomen and neck
- haematopoiesis
- transverse diameter greater than sagittal diameter
What is an important feature of thoracic vertebrae for its movement
its articular surfaces are set on the arc of a circle which allows for rotation rather than flexion and extension
Function of costal cartilage?
elasticity and mobility
Different types of ribs
- true ribs (1-7): attach to sternum directly by CC
- false ribs (8-10): attach to sternum indirectly through CC of 7th rib
- floating ribs (11-12): no attachment to sternum
What is the purpose of the costal groove?
for nerves and vessels to run through and acts as protection
What are the different parts of the sternum?
- manubrium
- body
- xiphoid process
Describe the relations of the sternal angle
- 2nd CC
- T4-5 intervertebral discs
- proximal and distal boundaries of aortic arch
- bifurcation of trachea
- superior limit of pulmonary trunk
- azygos vein opening to SVC
- ligamentum arteriosum
Describe the costovertebral joint
- joint between a rib and superior costal facet of corresponding vertebra and inferior costal facet of vertebra above
- synovial
Describe the costotransverse joint
- joint between tubercle of rib and transverse process of corresponding vertebrae
- joints 1-7: curved for rotary movement
- joints 8-10: flat facets for gliding movement
- movement significant in respiration
What are the boundaries of the thoracic inlet?
- T1
- 1 CC
- manubrium
What is contained in the thoracic inlet?
structures from the thorax to neck:
- vessels that supply and drain the head and neck
- trachea
- oesophagus
- vagus and recurrent laryngeal nerves
- phrenic nerves
structures from the thorax to the upper limb:
- subclavian vein and artery
- inferior trunk of BP
What are the boundaries of the thoracic outlet?
- T 10-12 ribs
- CC 7-10
Describe Thoracic Outlet Syndrome
- related to thoracic inlet
- compression of the nerves or blood vessels in the thoracic inlet
What are the 3 common areas of compression in Thoracic Outlet Syndrome?
- scalene triangle
- costoclavicular space between first rib and clavicle
- sub-pectoral space
What are Montgomery glands?
- visible portions on skin surface within areola of the breast
- sebaceous gland
Describe what is contained in the breast
- 15-25 lobes of lobules and ducts surrounded by fat and connective tissue stroma
- suspensory ligaments (Cooper’s ligaments): condensation of connective tissue
- connects deep fascia to dermis of skin
- supports the breast
- retromammary space: loose connective tissue layer between deep superficial fascia and deep fascia to allow movement over underlying structures
Describe breast tissue
- between superficial and deep layers of superficial fascia
- on pec major, serratus anterior and external oblique muscles
Where is deep pectoralis fascia found?
- between superifical and deep fascia
Describe vascular supply of the breast
- internal thoracic artery: mammary branches and anterior intercostal arteries
- axillary artery: lateral thoracic artery and thoraco-acromial artery
Describe vascular drainage of the breast
veins follow the arteries and drain to mainly axillary and internal thoracic veins
Describe lymph drainage of the breast
- areola and lateral quadrants: axillary lymph nodes
- medial quadrants: parasternal lymph nodes to opposite breast
- inferior quadrants: inferior phrenic lymph nodes
What can excessive development of pec minor result in?
compression of the subclavian artery and vein which can result in thoracic outlet syndrome
What muscles assist with inspiration and expiration?
- serratus anterior
- serratus posterior superior and inferior
