Bony thoracic cage
- 1. Thoracic Cage The joints, Intercostal spaces, Respiratory Movements, Relations of apex of lung, Pleura, Mediastinum @drsatyajitsaha 1
- 6. Typical Thoracic Vertebra forming Articulations @drsatyajitsaha 6
- 7. Atypical Thoracic Vertebra Vertebra TXII @drsatyajitsaha 7
- 8. Types of Ribs? Ribs False Ribs (8-12) Vertebro- chondral (8-10) Vertebral (11-12) True Ribs (1-7) Vertebroster al (1-7) @drsatyajitsaha 8
- 9. Head of a Typical vs Atypical Rib @drsatyajitsaha 9
- 10. Sternum & Sternal Angle @drsatyajitsaha 10
- 12. Articulation Between the Bones to Form the Bony Thoracic Cage (Oblique View) @drsatyajitsaha 12
- 13. Articulation Between the Bones to Form the Bony Thoracic Cage (Superior View) @drsatyajitsaha 13
- 15. Costo-Vertebral Joints Two convex facets from the head attach to two adjacent vertebrae, at the inferior costal facet of the superior vertebra, and the superior costal facet of the inferior vertebra respectively. This forms the synovial planar (gliding) joint. @drsatyajitsaha 15
- 16. Ligaments of Costo-Vertebral Joint @drsatyajitsaha 16
- 18. Triradiate Ligament Attachment Triradiate ligament associated with Attachment Typical rib Attached to the anterior part of the head of each rib • ascends and is connected with the body of the vertebra above, the superior fasciculus • descends to the body of the vertebra below, the inferior one • the middle one, is horizontal and is attached to the intervertebral fibrocartilage, 1st Rib Fibers are attached to the body of the last cervical vertebra (C7), as well as to that of the first thoracic (T1) 10th, 11th, 12th Rib The fibers of the ligament in each case are connected to the vertebra above, as well as to that with which the rib articulates @drsatyajitsaha 18
- 19. Radiate/Triradiate Ligament Relations (front) Left the thoracic ganglia of the sympathetic trunk the pleura Right the thoracic ganglia of the sympathetic trunk the pleura azygos vein @drsatyajitsaha 19
- 20. Intraarticular Ligament of Head of Rib Joint Cavity @drsatyajitsaha 20
- 21. Intraarticular Ligament of Head of Rib Situated in the interior of the joint Attached by one extremity to the inter-articular crest of the head of the rib, other to the intervertebral fibrocartilage Divides the joint into two cavities @drsatyajitsaha 21
- 26. Costo-transverse Joint The joint formed between the facet of the tubercle of the rib and the adjacent transverse process of a thoracic vertebra. Synchondrosis type of joint Allows only gliding movement Absent in the eleventh and twelfth ribs @drsatyajitsaha 26
- 27. Costo-transverse Ligaments Name of the Ligament Costal Attachment Vertebral attachment Posterior/inferior Costo-transverse ligament Posterior surface of the neck Anterior surface of the transverse process of the corresponding vertebrae Superior costotransverse ligament Upper border of the neck of a rib Transverse process of the vertebra above Lateral costotransverse ligament Non-articular part of the tubercle of the rib. Posterior surface of the tip of a transverse process of a corresponding vertebra @drsatyajitsaha 27
- 28. Function of Costo-transverse Ligament Support and prevent dislocation of ribs. Their posterior surfaces provide attachment points for the extensor muscles (deep group) of the back. @drsatyajitsaha 28
- 31. Layers of Thoracic Wall @drsatyajitsaha 31
- 35. Intercostal Muscles EXTERNUS: Sternum to tubercle of the ribs. Anteriorly – ant intercostal membrane. Posteriorly – fleshy Direction of fibers Anteriorly – downwards, medially. Posteriorly - downwards & laterally. INTERNUS: Sternum to posterior angles of rib. Anteriorly fleshy. Posteriorly - post intercostal membrane. Direction of fibers Anteriorly - downwards & laterally. Posteriorly - downwards, medially. @drsatyajitsaha 36
- 36. Intercostal Muscles INTIMUS: Transversus thoracis (subcostalis,sternocostalis) Middle 2/4th of the ICS. Absent in upper 2 spaces. Direction of fiber same as internus. Neurovascular space beween the INTERNUS & INTIMUS. @drsatyajitsaha 37
- 37. Internal Thoracic Artery Branch of 1st part of Subclavian artery. Branches Pericardiacophrenic artery. Mediastinal. Pericardial. Sternal. Anterior intercostal – upper 6 spaces. Perforating – in females fourth to sixth are enlarged to supply the breast. Musculo-phrenic – 7th to 9th anterior intercostal arteries. Superior epigastric artery – anastomoses with inferior epigastric artery branch of external iliac artery.@drsatyajitsaha 38
- 38. Branches Internal Thoracic Artery InternalThoracicArtery Pericardiacophrenic artery Mediastinal Pleural Sternal Anterior Intercostal Artery Perforating Artery Musculo-phrenic Artery Superior Epigastric Artery@drsatyajitsaha 39
- 39. Anterior Intercostal Spaces & Arteries @drsatyajitsaha 40
- 40. Ant Intercostal Artery Upper 6 – Internal Thoracic Artery. Lower 3 – Musculo-phrenic artery (internal thoracic). Breaks into 2 branches, upper one along the lower border of upper rib & lower one along the upper border of lower rib. Anastomose with the posterior intercostal branch at the junc of the ant 1/3rd & post 2/3rd of the space. @drsatyajitsaha 41
- 42. Posterior Intercostal Artery Upper 2 – Superior Intercostal artery – costo-cervical trunk – subclavian artery. Lower 9 – descending thoracic aorta. Anastomose with the upper ant intercostal artery. Collateral branch (near the angle) anastomose with the lower ant intercostal artery. @drsatyajitsaha 43
- 43. Anastomosis between Anterior & Posterior Intercostal Arteries @drsatyajitsaha 44
- 44. Coarctation of Aorta In coarctation of aorta, blood flow through the posterior intercostal arteries is reduced. To compensate for the reduced flow, more blood now flows through the anterior intercostal arteries. Because of this increased blood flow through the anterior intercostal arteries, they become dilated and tortuous. The dilated artery erode the costal groove, leading to rib notching, a radiological feature.@drsatyajitsaha 45
- 45. Rib Notching in X-ray @drsatyajitsaha 46
- 46. Anterior Intercostal Veins ANT INTERCOSTAL VEIN Upper 6 – Internal thoracic v. Lower 3 – Musculo-phrenic v @drsatyajitsaha 47
- 47. Posterior Intercostal Vein Rt 1st: Rt Brachio-cephalic v. Rt 2nd to 3rd : Rt sup intercostal v – arch of azygos. Rt 5th to 11th : vertical part of azygos. Lt 1st: Lt Brachio-cephalic v. Lt 2nd to 3rd: Lt superior intercostal v - Lt Brachio-cephalic v. Lt 5th to 7th: Superior hemi-azygos v – azygos v. Lt 8th to 11th: Inferior hemi-azygos v – azygos v.@drsatyajitsaha 48
- 50. Anastomosis Between Anterior Posterior Intercostal Arteries & Nerves @drsatyajitsaha 51
- 51. PLEURAL TAP / THORACOCENTESIS @drsatyajitsaha 52
- 53. Direction of the Muscle Pull A B C A B C External Intercostal Internal Intercostal (interosseus part) Internal Intercostal (intercartilaginous part) @drsatyajitsaha 54
- 54. Muscles of Relaxed Inspiration @drsatyajitsaha 55
- 55. Elevation of Ribs (Pump handle movement) Increases the Antero- posterior diameter Action of External Intercostal aided by inter- chondral fibers of Internal Intercostal. @drsatyajitsaha 56
- 56. Pump Handle Movement Quiet respiration- only first pair of ribs moves but little. On hypernoea .the 2nd and 6th ribs which slopes obliquely downwards and forwards from their joints with the spinal column , moves upwards to assume a more horizontal position due to contraction of the external internal costal muscles. Increases in the anterior- posterior diameter of the thorax. @drsatyajitsaha 57
- 57. Elevation of Ribs (Bucket handle movement) Increases the transverse diameter Action of External Intercostal. @drsatyajitsaha 58
- 58. Bucket Handle Movement This movements brings about the increase in transverse diameter of the thorax by the movement of the LOWER 7TH TO 10 RIB which swings outward and upwards @drsatyajitsaha 59
- 59. Combination of Pump Handle & Bucket Handle Movements Increases the antero-posterior & transverse diameter @drsatyajitsaha 60
- 60. Contraction of the Diaphragm Increases the vertical diameter Contraction of diaphragm, pulls the diaphragm downwards. This leads to increase in the vertical diameter. @drsatyajitsaha 61
- 61. C3,C4,C5 - Keeps me alive 1. During inspiration, Phrenic nerve (C3,C4,C5) stimulation causes diaphragm to contract and draw the central tendon part downwards. 2. Cause an increase in transverse diameter of the thorax. 3. Accounts for 75% of the tidal volume. 4. Hence Phrenic nerve is the nerve of inspiration. @drsatyajitsaha 62
- 62. Muscles of Forced/Active Inspiration @drsatyajitsaha 64
- 63. Muscles of Forced/Active Inspiration Contraction of the accessory muscles of breathing : Scalenes – elevates the upper ribs. Sternocleidomastoid – elevates the sternum. Pectoralis major and minor – pulls ribs outwards. Serratus anterior – elevates the ribs (when the scapulae are fixed). Latissimus dorsi – elevates the lower ribs. @drsatyajitsaha 65
- 65. Muscles of Forced Exhalation @drsatyajitsaha 67
- 66. Muscles of Forced Expiration Anterior abdominal muscles contracts – increases intrabdominal pressure – pulls the lower ribs downwards and medially – push the diaphragm upwards Internal intercostal muscles - passess obliquely downward and posteriorly from ribs to ribs – contracts – pull the upper ribs downward @drsatyajitsaha 68
- 67. Types of respiration In babies and young children, the ribs are nearly horizontal. Thus, babies have to rely mainly on the descent of the diaphragm to increase their thoracic capacity on inspiration. Because this is accompanied by a marked inward and outward excursion of the anterior abdominal wall, which is easily seen, respiration at this age is referred to as the abdominal type of respiration. After the 2nd year of life, the ribs become more oblique. Females tend to rely mainly on the movements of the ribs rather than on the descent of the diaphragm on inspiration. This is referred to as the thoracic type of respiration. Males use both the thoracic and abdominal forms of respiration but mainly the abdominal form. @drsatyajitsaha 69
- 77. Costal Pleura (Tracing in Front) Directed medially downwards from sternoclavicular jt to sternal angle. Directed downwards up to 4th costal cartilage on both sides. On the right side, the line passes vertically downwards up to the xiphisternal jt and turn laterally across the right costo-xiphoid angle & continues with the costo-diaphragmatic line of reflection. On the left side, the line deviates laterally from the sternum and descends close to the sternum up to the 6th costal cartilage & turns laterally at the costo- diaphragmatic line of reflection. @drsatyajitsaha 79
- 78. Posteriorly continuous with the mediastinal pleura along the costo – vertebral reflexion extending from a point 2.5 cm lateral of the 7th cervical spine to a point 2.5cm lateral to the 12th thoracic spine. Continuous with the cervical pleura along the inner border of the 1st rib. Costal Pleura (tracing behind) Costal Pleura (tracing above) @drsatyajitsaha 80
- 79. Continuous with the diaphragmatic pleura along a line known as the costo- diaphragmatic reflexion. Formed by joining the following points: Xiphi-sternal joint (Rt)/left 6th costo-sternal joint. 8th costal cartilage in the mid-clavicular line. 10th rib in the mid-axillary line. A point 2.5 cm lateral to the 12th thoracic spine. Costal Pleura (tracing below) @drsatyajitsaha 81
- 81. Suprapleural Membrane/Sibson’s Fascia 1. Musculo-fascial expansion. 2. Dome shaped. 3. Protects the apex of lung and the cervical pleura from the structures at the root of neck. 4. Musculo part – scalenus minimus. 5. Fascial part – endothoracic fascia. 6. Posteriorly attached to the tip of transverse process of the 7th cervical vertebra. 7. Anteriorly attached to the inner border of the first rib. 8. Medially continuous with the pretracheal fascia by the side of the trachea.@drsatyajitsaha 83
- 82. Mediastinal Pleura (Above The Root Of Lung) Structures on right side: Rt brachio-cephalic vein. Superior vena cava. Arch of azygos vein. Brachio-cephalic trunk. Right phrenic & vagus nerve. Trachea & oesophagus. Structures on left side: Left brachio-cephalic vein. Superior intercostal vein. Arch of aorta. Left common carotid artery. Left subclavian artery. Left phrenic & vagus nerve. Left recurrent laryngeal nerve. Trachea & oesophagus. @drsatyajitsaha 84
- 83. Mediastinal Pleura At The Root Of Lung (Before Backwards) @drsatyajitsaha 85
- 84. Mediastinal Pleura (At The Root Of Lung (Above Downwards Right Side) Structures on right side: Rt brachio-cephalic vein. Superior vena cava. Arch of azygos vein. Brachio-cephalic trunk. Right phrenic & vagus nerve. Trachea & oesophagus.@drsatyajitsaha 86
- 85. Mediastinal Pleura (At The Root Of Lung (Above Downwards Left Side) • Left brachio-cephalic vein. • Superior intercostal vein. • Arch of aorta. • Left common carotid artery. • Left subclavian artery. • Left phrenic & vagus nerve. • Left recurrent laryngeal nerve. • Trachea & oesophagus. Arch of Aorta @drsatyajitsaha 87
- 86. RIGHT SIDE ABOVE DOWNWARDS: Upper lobe bronchus. Pulmonary artery. Rt principal bronchus. Lower pulmonary vein BEFORE BACKWARDS: Upper Pulmonary vein. Pulmonary artery. Bronchus. LEFT SIDE ABOVE DOWNWARDS: Pulmonary artery. Lt principal bronchus. Lower pulmonary vein. BEFORE BACKWARDS Upper Pulmonary vein. Pulmonary artery. Bronchus. Mediastinal Pleura(At The Root Of Lung) @drsatyajitsaha 88
- 87. Mediastinal Pleura(Below The Root Of Lung) Forms a bilaminar fold known as the Pulmonary ligament. @drsatyajitsaha 89
- 88. Pleural Space/Cavity The potential space between the two layers of the pleura i.e the visceral & parietal. Contains pleural fluid which helps in maintaining the surface tension & hence the two can slide over each other. No anatomical connection between the two pleural cavities on two sides. Pleural fluid is a serous fluid which is secreted by the pleura. @drsatyajitsaha 90
- 89. Applied Anatomy of Pleura Pleural effusion. Pneumothorax Open Tension Hemothorax. Pyothorax. Pleural tap. Pleurisy/ Pleuritis Dry. Wet. @drsatyajitsaha 91
- 96. STRUCTURES IN THE SUPERIOR MEDIASTINUM @drsatyajitsaha 98
- 97. ARRANGED INTO THREE GROUPS: Retro Sternal – Origins of sterno-thyroid & sterno-hyoid muscle (strap muscles) Thymus gland (if present) SVC, Right and left brachio-cephalic vein, Left superior intercostal vein. Intermediate – Arch of aorta and its 3 branches. Phrenic nerve, Vagus nerve & Cardiac nerves. Paravertebral – Trachea, Oesophagus, Thoracic duct. Left Recurrent laryngeal nerve. Origin of longus colli muscle. STRUCTURES IN THE SUPERIOR MEDIASTINUM @drsatyajitsaha 99
- 98. Superior & inferior sternopericardial ligaments. Loose areolar tissue & retro-sternal lymph nodes. Mediastinal artery. STRUCTURES IN THE ANTERIOR MEDIASTINUM @drsatyajitsaha 100
- 99. Pericardium with the heart. Ascending aorta and the pulmonary trunk. Four (4) pulmonary veins. Lower part of SVC and the arch of azygos vein. Bifurcation of trachea, right & left bronchi. Phrenic nerves & pericardiacophrenic vessels. STRUCTURES IN THE INTERMEDIATE MEDIASTINUM @drsatyajitsaha 101
- 100. STRUCTURES IN THE POSTERIOR MEDIASTINUM Pulmonary Ligament @drsatyajitsaha 102
- 101. STRUCTURES IN THE POSTERIOR MEDIASTINUM Pulmonary Ligament @drsatyajitsaha 103
- 102. LONGITUDINAL STRUCTURES: Esophagus. Descending aorta. Azygos & hemi- azygos vein. Thoracic duct. Vagus nerve. Splanchnic nerves. Posterior mediastinal lymph nodes. TRANSVERSE STRUCTURES: Termination of superior & inferior hemi – azygos vein. Deviation of thoracic duct from right to left. Posterior intercostal arteries. Posterior intercostal vein. STRUCTURES IN THE POSTERIOR MEDIASTINUM @drsatyajitsaha 104
- 103. Inspiration is an active process, thoracic cavity changes in size- how? Phrenic nerve stimulation causes diaphragm to contract (and drop) Thoracic cavity enlarges, air pressure drops and atmospheric pressure forces air in External intercostal contract, elevate sternum Pleural membranes moves out (and together) @drsatyajitsaha 105