Sternum

Looks like

A flat, dagger-shaped bone about 15–20 cm long down the middle of the chest, with the ribs' cartilages joined to its edges.

What it does

Closes the front of the rib cage, shields the heart and anchors the chest and neck muscles.

Keeping it well

Breaks mostly in car crashes against the steering wheel or seat belt; a broken sternum can hide a bruised heart, so it is checked with an ECG. Pain at the rib joints beside it that worsens on pressing is usually harmless costochondritis — but chest pain with breathlessness or sweating is never assumed to be that.

Its parts

• Manubrium
• Body of sternum
• Xiphoid process

Related conditions

• Acromegaly
• Costochondritis
• Fractures
• Fragility fracture
• Frailty & falls in older age
• Hyperparathyroidism
• Osteogenesis imperfecta (brittle bone disease)
• Osteomalacia & rickets
• Osteomyelitis (bone infection)
• Osteoporosis
• Paget's disease of bone
• Pleural effusion
• Pneumothorax
• Sarcoma
• Vitamin B1, C and other deficiencies
• Vitamin D deficiency