Skeletal system · Chest

Costal cartilages !

The costal cartilages join the ribs to the breastbone at the front; their flexibility lets the chest expand with each breath.

Official name: Costal cartilage

Opens in the Durgical app, no sign-up needed.

What it is

Bars of cartilage that join the front ends of the upper ten ribs to the sternum or to the cartilage above.

What it does

Give the rib cage its springiness, so the chest can expand when you breathe in.

Key facts

Where

Hyaline cartilage at anterior ends of ribs 1–10; ribs 11–12 have only cartilage tips

Attaches

Ribs 1–7 to sternum (true ribs); 8–10 to cartilage above, forming costal margin

Function

Elasticity of rib cage for breathing; 1st sternocostal joint is a synchondrosis

Relations

In front

Pectoralis major over the upper cartilages; rectus abdominis attaches to cartilages 5–7

Behind

Internal thoracic artery and veins with the parasternal lymph nodes, on the transversus thoracis; then endothoracic fascia and pleura

Below

The lower cartilages give origin to the costal part of the diaphragm and to transversus abdominis on their inner surface

Medial

Sternum: cartilages 1–7 reach it directly; 8–10 join the cartilage above to form the costal margin

How to find it

The costal margin is felt along the lower edge of the chest from the xiphoid to the lateral side. The 2nd cartilage is found beside the sternal angle and the others are counted down from it, finger in each space; in thin people the costochondral junctions are felt as a slight step.

Examination

• Palpation of each sternocostal and costochondral junction: reproduction of the person's pain supports costochondritis, but cardiac and other causes of chest pain are excluded first
• Hooking manoeuvre: the examiner curls the fingers under the lower costal margin and pulls forward; pain or a click suggests slipping rib syndrome of cartilages 8–10

On imaging

Cartilage is not seen on plain radiographs unless it calcifies, which is common with age and can mimic lung nodules. CT shows costochondral fractures, Tietze swelling and, in pectus excavatum, the depth of the deformity (Haller index).

Common problems

• Costochondritis: tender, sharp chest-wall pain where the cartilage meets the sternum; it is harmless but can feel like heart pain.

How it is diagnosed

Exam and X-ray; CT finds small fractures and lung injury.

Treatment

• Pain control and deep-breathing exercises to prevent pneumonia; surgical plating for flail chest.

Clinical notes

• Flail chest: when segments of adjacent ribs or cartilages are broken in two places, the loose segment moves inward on inspiration (paradoxical movement); anterior flail can follow costochondral separation or CPR
• Rib cartilage is a common graft source for nasal, ear and airway reconstruction
• In rickets the costochondral junctions enlarge into a row of bumps (rachitic rosary)
• Pectus excavatum can compress the heart and is linked with connective tissue disorders such as Marfan syndrome; it may be corrected surgically, and carinatum is often treated with external bracing

Development

They are the front ends of the embryonic rib models, grown from the costal processes of the thoracic vertebrae, that never turn into bone. They stay hyaline cartilage, which keeps the chest wall springy; the 1st cartilage is often the first to calcify in adults.

Related conditions

• Flail chest
• Costochondritis

Test yourself

Think of the answer, then tap the question to see it.

Add to my cards (5)

Educational information, not medical advice. For any symptom, see a health professional.

Its names

Official Latin (TA2)

cartilago costalis TA2 1140

Official Spanish (DeCS)

Cartílago costal DeCS D066186

English (TA2)

Costal cartilage

Sources: Terminologia Anatomica (TA2); DeCS; Anatomy, Thorax, Ribs; Anatomy, Thorax, Sternum.

Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake

Send

Representative model, for educational purposes only.