Extensor pollicis longus

Looks like

A deep forearm muscle from the ulna, its tendon turning around a bony knob on the back of the radius to the thumb tip.

What it does

Straightens the thumb tip and pulls the thumb back.

Keeping it well

Can rupture weeks after a wrist fracture; sudden inability to lift the thumb needs a hand surgeon.

Related conditions

• Botulism
• Compartment syndrome
• De Quervain's tenosynovitis
• Fibromyalgia
• Frailty & falls in older age
• Heat exhaustion & heatstroke
• Lymphangitis
• Malnutrition & refeeding syndrome
• Muscular dystrophy
• Polymyalgia rheumatica
• Rhabdomyolysis
• Sarcoma
• Sarcopenia
• Tetanus