Thumb hypoplasia in children: A case report

Abstract

Thumb hypoplasia is a component of radial longitudinal deficiency. The severity of hypoplasia can range from a slightly smaller thumb to a complete absence. They are often categorised using Blauth classification to recommend appropriate treatment. Type II is characterised by the first web-space narrowing, underdeveloped or absence of thenar muscles, thumb extrinsic and metacarpophalangeal joint instability. The author reviews a 7-year-old male patient who visits
the hospital due to a small thumb, narrowing web I-II and limiting to flexing the interphalangeal joint. He underwent a first web-space release using flap Z-plasty, stabilised the metatarsal joint and opponensplasty transfer of the flexor digitorum superficialis of the IV finger to increase the opposition of the thumb. Results were assessed according to subject and object criteria. The author proposed that this technique could be reliable for treating other cases with thumb hypoplasia type II and IIIB.