Fingernails

Looks like

Hard, clear plates of keratin on the back of each fingertip, growing from a root under the skin fold.

What it does

Protect the fingertips and help pick up small things; they grow about 3 mm a month.

Keeping it well

Keep them short and dry. A new dark stripe along a nail, especially with the colour spreading to the skin, needs checking for melanoma.

Related conditions

• Carpal tunnel syndrome
• De Quervain's tenosynovitis
• Dupuytren's contracture & trigger finger
• Fungal nail infection (onychomycosis)
• Ganglion cyst
• Juvenile idiopathic arthritis
• Lichen planus
• Pseudogout (calcium pyrophosphate disease)
• Raynaud's phenomenon
• Repetitive strain & overuse injury
• Rheumatoid arthritis
• Warts, molluscum and skin infections