Children's Hospital Colorado

Finger/Thumb Hypoplasia or Aplasia

What is finger/thumb hypoplasia or finger/thumb aplasia?

  • Finger/thumb hypoplasia is when a baby is born with a finger or thumb that is not developed completely (it is usually small in size).
  • Finger/thumb aplasia is when a baby is born without a finger or thumb (it is missing).
  • The condition may or may not involve the other structures of the finger/thumb (bones, tendons, ligaments, muscles, joints and nerves).

What causes finger/thumb hypoplasia or aplasia?

Doctors do not know why finger/thumb hypoplasia or aplasia occurs, but they do know that it is often associated with specific syndromes and other hand differences.

Get to know our pediatric experts.

Sarah Sibbel, MD

Sarah Sibbel, MD

Orthopaedic Surgery

Cailin Brazeau, PA-C

Cailin Brazeau, PA-C

Physician Assistant