anatomy/rib-cage·Bone
Rib cage
Thorax (ribs and sternum)
12 pairs of ribs, the sternum and the thoracic vertebrae. The cage protects heart and lungs and moves with every breath.
// Structure & location
According to OpenStax, 12 pairs of ribs and the sternum form the thoracic cage. At the back, all ribs attach to the thoracic vertebrae. The top seven pairs connect directly to the sternum by their own cartilage (true ribs). Pairs 8 to 10 attach via the cartilage of the rib above, while pairs 11 and 12 end freely in the abdominal wall.
// Function
The rib cage protects the heart, lungs and great vessels and provides attachment for chest, abdominal, back and breathing muscles. When you breathe in, the diaphragm pulls down and the intercostal muscles pull the ribs up and out, enlarging the chest cavity.
// For training & sport
- When lifting heavy, take a deep breath and brace the abs. The pressure in chest and abdomen stabilises the trunk. This is called the Valsalva manoeuvre.
- The Valsalva manoeuvre briefly raises blood pressure sharply. With high blood pressure or heart problems, check with a doctor first.
// Good to know
The rib cartilages make the rib cage elastic. That lets it expand when breathing and partly absorb impacts.
// Sources
- LehrbuchOpenStax – Anatomy and Physiology 2e, Chapter 7 Review: The Axial Skeleton ↗
- LehrbuchOpenStax – Anatomy and Physiology, 11.4 Axial Muscles of the Abdominal Wall and Thorax ↗
last reviewed: 2026-11-14