The windblown hand: correction of the complex clasped thumb deformity.

The complex clasped thumb deformity associated with a windblown hand requires correction of three distinct deficits: an adduction contracture of the thumb-index web space, a flexion-volar subluxation contracture of the thumb metacarpophalangeal joint, and severe hypoplasia of the superficial thenar muscles. Severe contractures of the thumb web space are best released by an extensive soft-tissue release and skin coverage with a large, dorsal ration-advancement flap. The thumb metacarpophalangeal joint flexion contracture is corrected by an extensive soft-tissue release, often accompanied by metacarpophalangeal joint fusion. An opponensplasty substitutes for the lack of thenar muscle. Correction of all of the deficits is required to achieve good thumb function.