Author: Brian Wu PhD. MD Candidate, Keck School of Medicine, Los Angeles, USA; Chief Editor: Hon A/Prof Amanda Oakley, Dermatologist, Hamilton, New Zealand, February 2016.

What is ainhum?

Ainhum is a condition that refers to the auto-amputation of a digit, usually the 5th toe. This is sometimes bilateral and can also, though less frequently, affect the fingers. It is a poorly understood phenomenon and medical literature is somewhat lacking. It is also known as dactylopsis spontanea.

Who gets ainhum?

Ainhum occurs equally in males and females. Risk factors for getting ainhum include:

What causes ainhum?

Ainhum occurs due to a fibrotic band which encircles a digit and constricts it, gradually causing the auto-amputation. 

What are the clinical features of ainhum?

Diagnosis of ainhum is based upon the following three features:

Patients with ainhum may present with:

Ainhum may be staged according to the following criteria:

What is the treatment for ainhum?

Treatment for ainhum may include:

What is the outcome for ainhum?

Ainhum in itself is rarely fatal, but may put patient at risk for:

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