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• Regional anatomy


  A method of studying the body as entire regions or compartments

  
• Regional anatomy explores the relationships of structure and function of tissues within a given region
• Regional anatomy allows for understanding of normal vs. abnormal anatomy
• Regional anatomy integrates multiple body systems
• Thoracic region/tārāuma


  Superior "Trunk" between neck/porokakī and abdomen/kōpū

  
• Thoracic region/tārāuma


  • Consists of wall and cavity
  • Has boundaries and apertures

  
• General functions of the thoracic region/tārāuma

  • Respiration
  • Protection of vital organs
  • Passage of structures

  
• Thoracic cavity


  • Consists of two lateral pleural cavities and one mediastinum

  
• Pleural cavities


  Own pleural cavity for each lung/pukapuka
• Mediastinum


  Centrally located "medial septum/partition" that separates the pleural sacs
• Subdivisions of the mediastinum


  • Superior
  • Inferior
• Thoracic region/tārāuma


  Continuation of structures also found in the neck/porokakī, abdomen/kōpū, upper limb, and axillary region/pūkēkē

  
• Structures associated with the thoracic wall


  • Skin and superficial fascia
  • Bones of shoulder girdle
  • Muscles (& deep fascia)

  
• Muscles associated with the thoracic wall

  • Pectoralis major
  • Pectoralis minor
  • Serratus anterior
  • Rectus abdominis
• Pectoralis major


  • Attaches: clavicle, sternum, costal cartilages à humerus
  • Innervated: medial and lateral pectoral nerves

  
• Pectoralis minor


  • Attaches: coracoid process à ribs 3,4,5
  • Innervated: medial pectoral nerve
• Serratus anterior


  • Attaches: ribs 1-9, intercostal fascia à medial border of scapula
  • Innervation: long thoracic nerve

  
• Rectus abdominis


  • Attaches: costal cartilages of ribs 5-7, xiphoid process à pubic bones (& joint)
  • Innervation: Anterior rami of T7-T12 spinal nerves

  
• The muscles associated with the thoracic wall are similar between the rat and human, with anatomical differences reflecting the functional differences

  
• Thoracic wall


  • Apertures (superior, inferior, anterior, lateral, posterior)
  • Joints (posterior, anterior)
  • Intercostal space
  • Muscles
  • Innervation and vasculature
  • Endothoracic fascia
  • Floor (diaphragm)
• Joints of the thoracic wall

  Posterior: Vertebral column, costovertebral, costotransverse

  Anterior: Sternum, sternocostal, costochondral, interchondral

  
• Intercostal space


  • Intercostal muscles (external, internal, innermost)
  • Intercostal nerves
  • Intercostal arteries and veins
  • Endothoracic fascia

  
• Intercostal muscles


  External: Contract to lift thoracic cage (inspiration)

  Internal and innermost: Contract to lower thoracic cage (forced expiration)
• Endothoracic fascia


  Connective tissue layer lining inner wall of thorax, external to pleura
• Diaphragm


  • Radiating muscle fibres
  • Central tendon
  • Sternal, costal, lumbar attachments
  • Apertures (aortic, vena caval, oesophageal)
• Mechanics of breathing


  Inspiration: External intercostals contract, rib cage rises, diaphragm contracts, lung volume increases, air flows in

  Expiration: External intercostals relax, rib cage descends, diaphragm relaxes, lung volume decreases, air flows out
• Many joints are found within the structures that comprise the thoracic cage, and their structure reflects their function
• The intercostal space is filled with muscles, blood vessels and nerves
• The endothoracic fascia is a thin layer of connective tissue situated between the pleura and the intercostal muscles, allowing surgical intervention of the thoracic wall without the interruption of the pleura
• The floor of the thoracic cavity is filled by the diaphragm, which is also the primary muscle of respiration
• The diaphragm has three apertures allowing the passage of structures between the thoracic and abdominal cavities

  
• The muscles, thoracic cage, diaphragm and lungs (pleura) work together during the inspiration and expiration phases of breathing
• Pleural cavities


  Two lateral pleural cavities
• Pleura


  Lungs & pleura, One central mediastinum, Sternum (anteriorly) ! vertebral column (posteriorly), Subdivisions: superior/inferior, Heart & pericardium

  
• Pleura


  • Each lung/pukapuka = own pleura, Thin, double layer, Visceral pleura "inside", lung surface, Pleural cavity (potential space), Pleural (serous) fluid, Parietal pleura "outside", thorax, mediastinum, Continuous with each other, and attached to mediastinum by root of lungs/pukapuka
• Relationship between parietal and visceral pleura

  Potential space in the living, Filled with serous fluid, Friction free environment, Movement of lungs without pain, Negative intrapleural pressure which hold the parietal and visceral pleurae together, Movement of thoracic wall during inspiration = "stretch" of lungs, Damage to pleura disrupts pressure = collapse of lung tissue = pneumothorax

  
• Parietal pleura


  • Cervical, Costal, Diaphragmatic, Mediastinal
• Pleural recesses


  Normal respiration: lungs don't fill the whole thoracic cavity, Parietal pleura still lines the cavity, Visceral pleura still on lung surface, Pleural recesses = 2 layers of parietal pleura, Costodiaphragmatic, Costomediastinal
• Pleural Recesses: costodiaphragmatic
• Lungs/pukapuka


  Orientation, parts, fissures, surfaces, Root, Hilum, Non-symmetrical, cone-shaped, Apex, Base, Costal surface, Mediastinal surface, Larger on left due to heart, Root & hilum, Pulmonary ligament