THORAX ANATOMY: STRUCTURE LIST Labs 1-3 Thorax: Lab 1 Sternum • Manubrium • Body o Jugular notch • Xiphoid process o Clavicular notch • Sternal angle (T4/T5 vertebral level) Rib Osteology • Head • Costal cartilage • Neck • Costal groove • Tubercle • Intercostal space • Body (shaft) Rib Types • True ribs (1-7) • Floating ribs (11 and 12) • False ribs (8-10) Thoracic Wall Spaces/Boundaries • Superior thoracic aperture (thoracic • Costal arch (margin) outlet) • Intercostal space (numbering) • Inferior thoracic aperture • Subcostal space Thoracic Wall Muscles • External intercostal muscle • Innermost intercostal muscle • Internal intercostal muscle • Transversus thoracis muscle Thoracic Wall Vessels • Internal thoracic (mammary) artery • Superior epigastric artery (branches from subclavian) • Posterior intercostal artery • Anterior intercostal artery • Posterior intercostal vein • Musculophrenic artery Lung Surfaces • Costal • Diaphragmatic (base) • Mediastinal (medial) • Apex Lung Lobes • Right • Left o Superior (upper) o Superior (upper) o Middle o Inferior (lower) o Inferior (lower) Lung Fissures • Right oblique • Left oblique • Horizontal Other Lung Features • Hilum • Root • Left Lung Only o Cardiac notch o Lingula Pleura • Parietal pleura o Costal o Diaphragmatic o Mediastinal o Cervical o Pleural sleeve o Pulmonary ligament • Visceral pleura • Pleural cavity o Costodiaphragmatic recess Surface Anatomy Relative to Lung Regions • Apex (2-4 cm superior to medial 3rd of clavicle) • Anterior base: midclavicular line (6th rib) • Lateral base: midaxillary line (8th rib) • Posterior base: scapular line (10th rib) • Junction horizontal and oblique fissure (midaxillary 5th rib) • Horizontal fissure (4th rib anteriorly) • Oblique fissure: T3 spinous process to rib 6 anteriorly Diaphragm • Central tendon • Right and left hemidiaphragm & domes • Caval hiatus (T8) • Esophageal hiatus (T10) • Aortic hiatus (T12) • Diaphragm innervation o Motor: phrenic (C3,4,5) o Sensory: ▪ Central: Phrenic ▪ Periphery: intercostal (T5-T11) and subcostal nerve Thorax: Lab 2 Mediastinum Regions • Superior • Inferior o Anterior o Middle o Posterior Pericardium (Pericardial sac) • Fibrous pericardium • Pericardial cavity • Bare area of pericardium o Pericardial sac sinuses • Serous pericardium ▪ Transverse pericardial sinus o Parietal serous pericardium ▪ Oblique pericardial sinus o Visceral serous pericardium Heart surfaces • Anterior (sternocostal) • Right pulmonary • Inferior (diaphragmatic) • Heart base • Left pulmonary • Heart apex Heart borders • Right • Left (obtuse) • Superior • Inferior (acute) Sucli • Coronary (atrioventricular) sulcus • Posterior interventricular sulcus • Anterior interventricular sulcus • Crux Right atrium • Auricle (atrial appendage) • Interatrial septum • Crista terminalis • Fossa ovalis • Pectinate muscles • Orifice of tricuspid valve • Ostia o Superior vena cava o Inferior vena cava o Coronary sinus Right ventricle • Trabeculae carneae • Papillary muscles • Conus arteriosus (infundibulum) • Septomarginal trabecula (moderator • Tricuspid valve band) • Chordae tendineae Left atrium • Pulmonary veins • Pectinate muscles • Auricle (atrial appendage) • Orifice of mitral valve Left Ventricle • Thick myocardial wall • Papillary muscles • Trabeculae carneae • Chordae tendineae • Mitral valve Interventricular septum • Membranous portion • Muscular portion Great Vessels • Superior vena cava • Inferior vena cava • Ascending aorta o Aortic (semilunar) valve o aortic sinuses • Pulmonary trunk o Pulmonary (semilunar) valve o Pulmonary sinuses o Left pulmonary artery o Right pulmonary artery • Pulmonary veins Other Vessels • Right and left Brachiocephalic (innominate) veins o Right and left Internal jugular vein o Right and left Subclavian vein • Arch of aorta o Brachiocephalic trunk ▪ Right common carotid artery ▪ Right subclavian artery o Left common carotid artery o Left subclavian artery o Ligamentum arteriosum Aortopulmonary (AP) Window Boundaries • Superior: aortic arch • Medial: trachea, left main bronchus, • Inferior: left pulmonary artery esophagus • Anterior: ascending aorta • Lateral: left lung • Posterior: descending aorta • Within: Ligamentum arteriosum Conduction System (Model) • Sinu-atrial (sinoatrial) node • Left and right bundle branches • Atrioventricular node • Subendocardial branches (Purkinje • Atrioventricular (AV) bundle (of His) fibers) Coronary arteries • Right coronary artery o Sinu-atrial (sinoatrial) nodal artery o Right acute marginal branch o Posterior descending (interventricular) artery (if right dominant) • Left coronary artery • Left anterior descending artery (anterior interventricular artery) o Diagonal branches • Circumflex artery • Left obtuse marginal artery Coronary veins • Coronary sinus • Middle cardiac vein • Great cardiac vein • Small cardiac vein Nerves • Right and left phrenic nerve • Right and left vagus nerves • Right and left recurrent laryngeal nerves Thorax: Lab 3 Larynx Review • Thyroid cartilage • Epiglottis • Cricoid cartilage • Median cricothyroid ligament • Arytenoid cartilage Tracheobronchial Tree • Trachea o Cartilaginous rings o Carina • Bronchi o Main (primary) o Lobar (secondary) ▪ Upper ▪ Middle (right only) ▪ Lower o Bronchus intermedius o Segmental (tertiary) Pulmonary Arteries • Right and Left o Superior lobar artery o Interlobar artery Lymph Nodes • Bronchopulmonary (hilar) lymph nodes • Inferior tracheobronchial (carinal) lymph nodes • Thoracic duct Esophagus Nerves • Intercostal nerve • Right and left vagus nerves o Right and left recurrent laryngeal nerves o Esophageal plexus o Anterior and posterior vagal trunks • Sympathetic trunk o Sympathetic (paravertebral) ganglia o Greater splanchnic nerve o Rami communicantes Vessels • Azygos vein • Hemiazygos vein • Accessory hemiazygos vein • Posterior intercostal vein • Descending aorta (thoracic aorta) • Posterior intercostal artery • Thoracic duct .