Thorax Anatomy Hub
A structured, region-wise exploration of thoracic anatomy with cardiopulmonary clinical relevance.
Thorax Anatomy Hub
Bones
Skeletal framework forming the thoracic cage.
Thoracic Cage – Ribs, Sternum & Vertebrae
A look at the bony framework of the thorax, composed of the sternum, 12 pairs of ribs, and thoracic vertebrae, which protects vital organs and aids respiration.
Sternum Anatomy – Manubrium, Body, Xiphoid & Sternal Angle
The sternum, or breastbone, is a flat bone at the front of the chest. Learn its parts—manubrium, body, xiphoid—and the vital Sternal Angle of Louis landmark.
Ribs Anatomy – True, False, Floating + Typical vs Atypical
The 12 pairs of ribs form the main structure of the thoracic cage. Learn the differences between typical and atypical ribs, and their articulations with the vertebrae.
Thoracic Vertebrae (T1–T12) – Features & Costal Facets
The 12 thoracic vertebrae are unique for their costal facets, which articulate with the ribs. Explore the features of typical and atypical thoracic vertebrae.
Muscles
Muscles of respiration and thoracic wall stability.
Diaphragm – Anatomy, Openings & Respiration
An overview of the diaphragm, the primary muscle of respiration. Learn about its origins, central tendon, major openings (aortic, esophageal, caval), and motor innervation.
Intrinsic Thoracic Wall Muscles – Intercostals & More
An overview of the intrinsic muscles of the thoracic wall, including the external, internal, and innermost intercostal muscles that facilitate respiration.
Nerves
Autonomic and cardiac nerve supply of the thorax.
Thoracic Sympathetic Trunk – Ganglia & Splanchnic Nerves
Explore the thoracic sympathetic trunks, their ganglia, and the greater, lesser, and least splanchnic nerves that arise from them to supply abdominal organs.
Heart Nerve Supply – Sympathetic vs Parasympathetic
The heart's autonomic innervation is controlled by sympathetic (cardioacceleratory) and parasympathetic (cardioinhibitory) fibers via the cardiac plexuses.
Arteries
Major arterial channels within the thorax and heart.
Internal Thoracic Artery – Branches & CABG Use
A major artery of the anterior chest wall, the internal thoracic artery is a key vessel used in coronary artery bypass grafting (CABG) due to its durability.
Thoracic Aorta – Ascending, Arch, Descending & Branches
The thoracic aorta is the largest artery in the thorax. Explore its three parts—ascending, arch, and descending—and their key branches and clinical correlations.
Pulmonary Trunk – Course, Branches & Relations
The pulmonary trunk arises from the right ventricle and carries deoxygenated blood to the lungs. Learn its course, relations to the aorta, and clinical relevance.
Coronary Arteries – Heart Arterial Supply & Branches
An overview of the right and left coronary arteries, their major branches like the LAD, and their role in supplying oxygenated blood to the myocardium.
Veins
Venous drainage pathways of thoracic structures.
Superior Vena Cava (SVC) – Formation, Course & Tributaries
The SVC is a large vein that returns deoxygenated blood from the upper half of the body to the right atrium. Learn its formation, course, and major tributaries.
Azygos System – Azygos & Hemiazygos Veins Explained
The azygos system of veins drains the posterior walls of the thorax and abdomen, forming a crucial collateral pathway between the SVC and IVC.
Heart Venous Drainage – Coronary Sinus & Tributaries
Learn how venous blood is drained from the heart muscle, primarily through the coronary sinus and its tributaries, which empty into the right atrium.
Joints
Articulations permitting thoracic movement.
Anatomical Regions
Thoracic wall, pleura, mediastinum, and pericardium.
Thoracic Wall Layers – Skin, Fascia & Muscle Coverings
Explore the layers covering the thorax, from the skin and superficial fascia containing the breast, to the deep fascia and the numerous extrinsic muscles.
Thoracic Inlet – Superior Thoracic Aperture Anatomy
The superior thoracic aperture, or thoracic inlet, is the upper opening of the thoracic cavity, allowing passage of vital structures between the neck and thorax.
Intercostal Spaces – Muscles, VAN Bundle & Clinical
Explore the anatomy of the intercostal spaces between the ribs, detailing the three muscle layers and the neurovascular bundle (vein, artery, nerve).
Pleura – Cavities, Recesses & Clinical Notes
The pleura are serous sacs surrounding the lungs. Learn about the visceral and parietal layers, the pleural cavity, and key recesses like the costodiaphragmatic.
Mediastinum – Boundaries, Contents & Overview
The mediastinum is the central space in the thoracic cavity between the lungs, containing the heart, great vessels, trachea, and esophagus. Learn its boundaries.
Lungs
Respiratory structures and mechanics.
Lungs Anatomy – Lobes, Fissures, Hilum & Blood Supply
An overview of the lungs, the primary organs of respiration. Explore the lobes, fissures, hilum, and the dual (pulmonary and bronchial) blood supply.
Bronchial Tree – Trachea to Bronchioles & Alveoli
Follow the branching airways of the lungs, from the trachea to the principal, lobar, and segmental bronchi, down to the terminal and respiratory bronchioles.
Bronchopulmonary Segments – Surgical Lung Anatomy
Bronchopulmonary segments are the independent functional and surgical units of the lungs, each with its own segmental bronchus and pulmonary artery branch.
Trachea – Anatomy, Rings, Relations & Clinical
The trachea is a fibrocartilaginous tube extending from the larynx to the bronchi. Learn about its C-shaped rings, trachealis muscle, and clinical importance.
Mechanism of Respiration – Pump-Handle & Bucket-Handle
Learn how breathing works through the pump-handle and bucket-handle movements of the ribs and the contraction of the diaphragm, which alter thoracic diameters.
Heart
Structure, blood supply, and conduction system of the heart.
Heart Anatomy – Chambers, Valves & Conduction System
The heart is a muscular pump with four chambers that drives the circulatory system. This overview covers its basic structure, valves, and electrical conduction pathway.
Heart Chambers – Right vs Left Atria and Ventricles
A detailed look at the four chambers of the heart. Explore the unique features of the right and left atria and the powerful right and left ventricles.
Heart Valves – Mitral, Tricuspid, Aortic & Pulmonary
Learn how the heart's four valves—mitral, tricuspid, aortic, and pulmonary—ensure unidirectional blood flow and prevent regurgitation through the cardiac cycle.
Cardiac Conduction System – SA Node, AV Node & Purkinje
Explore the heart's electrical system, from the SA node (pacemaker) to the AV node and Purkinje fibers, which coordinates the rhythmic heartbeat.
Coronary Arteries – Heart Arterial Supply & Branches
An overview of the right and left coronary arteries, their major branches like the LAD, and their role in supplying oxygenated blood to the myocardium.
Other Structures
Additional thoracic organs of clinical relevance.
Thymus – Anatomy, Function & Clinical Relevance
The thymus is a primary lymphoid organ in the superior mediastinum, crucial for T-cell maturation. It involutes with age and is linked to myasthenia gravis.
Esophagus (Thorax) – Relations & Constrictions
The esophagus is a muscular tube connecting the pharynx to the stomach. This guide covers its thoracic course, relations, and four major anatomical constrictions.
Explore Related Anatomy Hubs
Cardiovascular System Hub
Heart, blood vessels, and circulation organized for system-wise anatomy learning.
Respiratory System Hub
Anatomy of airways, lungs, and the mechanics of respiration.
Neck Anatomy Hub
Triangles, fascia, vessels, nerves, viscera, and clinical anatomy of the neck.