Radiographic Anatomy

Comprehensive anatomy by body region — bones, joints, muscles, soft tissues, and radiographic landmarks

Thoracic Cage — Anterior View

Ribs, Sternum & Lungs

Anterior view of the thoracic cage demonstrating the sternum, ribs, costal cartilages, clavicles, lungs and mediastinum — the anatomical foundation for chest radiographic positioning.

Thorax

Bones

Sternum: manubrium, body, xiphoid process
12 pairs of ribs (7 true, 3 false, 2 floating)
Thoracic vertebrae T1–T12
Clavicles (×2)
Scapulae (×2)

Joints

Sternoclavicular joints
Costochondral junctions
Costovertebral joints
Costotransverse joints
Manubriosternal joint (Angle of Louis — T4/5 level)

Muscles

Diaphragm
External intercostals
Internal intercostals
Pectoralis major
Pectoralis minor
Serratus anterior

Soft Tissues

Heart (4 chambers — RA, LA, RV, LV)
Lungs: Right (3 lobes — upper, middle, lower), Left (2 lobes — upper, lower)
Trachea (bifurcates at T4/5 — carina)
Main bronchi
Aorta (ascending, arch, descending)
Superior and inferior vena cava
Pulmonary arteries and veins
Esophagus
Thymus
Mediastinum (anterior, middle, posterior)

Anatomical Landmarks

Jugular (sternal) notch — T2/3
Angle of Louis (manubriosternal junction) — T4/5
Xiphoid process — T9/10
Inferior angle of scapula — T7
Vertebra prominens (C7/T1)

Radiographic Anatomy Notes

PA chest: both lung fields, cardiac silhouette (CT ratio ≤ 0.50), mediastinum, trachea midline, hemidiaphragms, costophrenic angles. Normal cardiac borders: right = SVC + right atrium; left = aortic knob + pulmonary artery + left ventricle. Carina angle normally < 70°.

Clinical Relevance

Understanding this region's anatomy is essential for accurate patient positioning, image evaluation, and pathology identification. Key landmarks guide central ray placement and ensure optimal demonstration of the structures of clinical interest.

No anatomy diagrams available for this region

Anatomy diagrams for this body part will appear here once added.

References Used

Bontrager's Textbook · Merrill's Atlas · Clark's Positioning · Gray's Anatomy · OpenStax Anatomy & Physiology · Radiopaedia · StatPearls · ACR · ESR · RSNA · WHO

All educational content is originally written based on the medical concepts from these trusted references. No copyrighted text, tables, or illustrations are reproduced.