Abductor digiti minimi opponensplasty in hypoplastic thumb.

Ten cases of hypoplastic thumbs were treated by abductor digiti minimi opponensplasty in order to restore opposition of the thumb and reform the wasted thenar eminence. In eight of these ten cases operations were combined with multiple Z-plasty or rotation flap to correct the narrowing of the first web space. Adductor plasty using extensor indicis proprius was performed in six cases to restore the stability of the metacarpophalangeal joint of the thumb and ligament reconstruction of the carpometacarpal joint in one hand. In all cases, the transferred abductor digiti minimi was strong enough to abduct the thumb and provide good functional and cosmetic results. We modified Littler's procedure by transferring the origins of abductor digiti minimi muscle from the flexor carpi ulnaris to the palmaris longus tendon. Our modified method gave a better cosmetic appearance than that provided by Littler's method.