3D CONTENT
3D OSTEOLOGY
3D THORAX

THORACIC SKELETON ANATOMY

Author: Dr. Bogdan Leahu
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Thoracic skeleton anatomy 360-degree interactive viewer showing thoracic cage, ribs, sternum, costal cartilages, and thoracic vertebrae
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TABLE OF CONTENTS

THORAX OVERVIEW

What is the thoracic cage?

  • The thoracic cage is a structure made up of bones and cartilage that plays a vital role in protecting your thoracic organs like your heart, lungs, and great vessels
  • Composed of the ribs, thoracic vertebrae, and sternum, which together create a flexible yet sturdy framework crucial for your breathing
  • The thoracic cage forms a cavity that has two key openings

Thoracic Cage

Thoracic cage 360-degree viewer showing bony and cartilaginous structures protecting heart, lungs, and great vessels
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What does the thoracic cage consist of?

  • Consists of bony and cartilaginous structures
  • Protects your vital organs: heart, lungs, and great vessels
  • Formed by ribs, thoracic vertebrae, and sternum
  • Provides structural support and flexibility for your breathing

Thoracic Cavity

What does the thoracic cavity contain?

  • Houses and protects your heart and lungs
  • Allows space for your lung expansion during respiration
  • Lined by the thoracic skeleton for protection and movement efficiency

Superior Thoracic Aperture

Superior thoracic aperture showing upper opening of thoracic cavity bounded by first thoracic vertebra, manubrium, and first ribs
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What is the superior thoracic aperture?

  • Upper opening of your thoracic cavity
  • Slopes downward and forward
  • Boundaries:
    • First thoracic vertebra (back)
    • Manubrium of the sternum (front)
    • First ribs (sides)
  • Allows passage of your trachea, esophagus, and major blood vessels

Inferior Thoracic Aperture

Inferior thoracic aperture showing lower boundary of thoracic cavity bounded by twelfth thoracic vertebra and costal cartilages
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What is the inferior thoracic aperture?

  • Lower boundary of your thoracic cavity
  • Boundaries:
    • Twelfth thoracic vertebra
    • Eleventh and twelfth ribs (sides)
    • Costal cartilages of seventh to tenth ribs (front)
    • Subcostal angle formed at convergence
  • Sealed by your diaphragm
  • Separates your thoracic cavity from your abdominal cavity
  • Aids in your respiration

THORACIC FEATURES

What are the main thoracic features?

  • Your thorax features a well-designed framework that includes the costal arch for flexibility, intercostal spaces to facilitate rib movement, and the infrasternal angle as a key anatomical landmark
  • These structures work together to protect your vital organs and support efficient respiration through the expansion and contraction of your thoracic wall

Thoracic Skeleton

Bones of the thorax 360-degree viewer showing thoracic vertebrae, twelve pairs of ribs, and sternum
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What bones form the thoracic skeleton?

  • Comprises the bones forming your thorax
  • Bones of the Thorax:
    • Includes thoracic vertebrae, ribs, and sternum
  • Ribs:
    • Twelve pairs of elastic, curved bones
    • Attach posteriorly to your vertebral column and anteriorly to your sternum via costal cartilages
    • Functions: provide structural support, protect your thoracic organs, enable respiration through mobility
  • Sternum:
    • Long, flat bone in the center of your anterior thoracic wall
    • Provides structural support
    • Articulates with your clavicles (collarbones) and first seven pairs of ribs via costal cartilages

Infrasternal Angle

Infrasternal angle 360-degree viewer showing angle formed at xiphoid process where lower rib cage edges meet
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What is the infrasternal angle?

  • Angle formed at your xiphoid process where the lower rib cage edges meet
  • Serves as an anatomical landmark for diaphragm access

Costal Cartilages

Costal cartilages showing hyaline cartilage connecting ribs to sternum providing flexibility to thoracic wall
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What are the costal cartilages?

  • Hyaline cartilage connecting your ribs to your sternum or each other
  • Provides flexibility to your thoracic wall for respiration

Intercostal Spaces

Intercostal spaces showing eleven spaces between adjacent ribs containing intercostal muscles and neurovascular bundles
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What are the intercostal spaces?

  • Spaces between adjacent ribs and their costal cartilages
  • Eleven spaces on each side
  • Contents:
    • Intercostal muscles
    • Membranes
    • Neurovascular bundles
  • Function:
    • Allows your rib movement during respiration
    • Aids in your thoracic cavity expansion and contraction

BIBLIOGRAPHY

1. Henry G, Warren HL. Osteology. In: Anatomy of the Human Body. 20th ed. Philadelphia: Lea & Febiger; 1918. p. 129–97.