Unguis incarnatus (ingrown toenail)

An unguis incarnatus (ingrown nail) occurs when the edge of the nail grows into the surrounding skin, causing pain, redness and inflammation. It usually affects the big toe but can also occur on other toes or fingers.

Causes and risk factors

• incorrect nail cutting (too short or rounded)
• tight or pressing shoes
• foot deformities (e.g. hallux valgus, splayfoot)
• excessive sweating (hyperhidrosis)
• injuries or pressure (e.g. from sport)

Symptoms

• pain and a feeling of pressure
• redness and swelling of the nail fold
• possibly pus and inflammation in advanced cases
• granulation tissue (“proud flesh”)

Treatment

• early stage: foot baths, antiseptic ointments, gently lifting the nail edge
• podiatric: nail correction with a brace (e.g. BS or 3TO brace), gentle removal of ingrown corners, pressure relief
• medical: antibiotics for infections, painkillers
• surgical in severe cases: partial nail removal or treatment of the growth zone

Prevention

• cut nails straight, do not round them
• shoes with enough room for the toes
• keep feet dry and care for them regularly

Since 2022, nail brace treatment for ingrown toenails can be prescribed by a doctor (diagnosis group UI). More in our guide Ingrown toenail.