Case Reports: Reconstruction of Grade III Thumb Hypoplasia

Two boys, aged one year and three months and five years, with a grade III thumb hypoplasia were treated with the following surgical procedures.1) The third metatarsus including its metatarsal head and epiphysis was grafted to the base of the hypoplastic first metacarpus without microvascular anastomosis. The metatarsal head was placed on the trapezium to reconstruct a new carpometacarpal joint.2) The intrinsic and extrinsic muscles of the thumb were reconstructed with the multiple tendon transfers proposed by Yabe (1973).3) Following the release of the first web space, a lateral arm free flap was used for covering the skin defect and for simultaneous reconstruction of the thenar eminence.These procedures were separated into several staged surgeries. The follow-up periods were 2 years and 8 months, and 5 years.Radiographic examinations revealed a continuous longitudinal growth of the reconstructed first metacarpus with the patent epiphysial plate of the grafted metatarsus at the final follow-up. The newly formed carpometacarpal joints maintained adequate range of motion without instability.