Mirror Hand

Also known as: mirror hand deformity, mirror hand syndrome, ulnar dimelia.

What is mirror hand?

Mirror hand is a very rare congenital difference. In most cases, there is mirrored symmetry of the hand with a central digit and 3 digits on either side and no thumb. There are usually 7 or 8 digits, with middle, ring and small fingers seen on either side of the central digit.

Differences are often seen in the forearm and elbow as well. Movement in the fingers, forearm and elbow may be limited.

What causes mirror hand?

The exact cause is not known, though the genes responsible for positional information during limb development are likely involved. Mirror hand is diagnosed on prenatal ultrasound or at birth.

What are the symptoms of mirror hand?

Along with the physical appearance of the upper arm, hand and fingers, mirror hand is also characterized by limited range of motion of the affected limb.

What are mirror hand care options?

Reviewed by: Aaron J. Berger

This page was last updated on: September 16, 2025 12:36 PM