Lateral malleolus

Looks like

The bump on the outside of the ankle, the lower end of the fibula — it reaches lower than the inner ankle bone.

What it does

Forms the outer wall of the ankle joint and anchors the outer ankle ligaments.

Keeping it well

Most ankle sprains tear the ligaments just in front of it. Tenderness on the back edge or tip of the bone, or not managing four steps, means an X-ray (Ottawa rules).

Related conditions

• Achilles tendon rupture
• Acromegaly
• Chronic venous insufficiency
• Compartment syndrome
• Fractures
• Fragility fracture
• Frailty & falls in older age
• Growing pains
• Hyperparathyroidism
• Lymphangitis
• Lymphatic filariasis (elephantiasis)
• Lymphoedema
• Osteogenesis imperfecta (brittle bone disease)
• Osteomalacia & rickets
• Osteomyelitis (bone infection)
• Osteoporosis
• Paget's disease of bone
• Restless legs syndrome
• Sarcoma
• Superficial thrombophlebitis
• Varicose veins
• Venomous snakebite
• Vitamin B1, C and other deficiencies
• Vitamin D deficiency