Twenty-eight patients with thumb deformity associated with spastic paralysis were selected, carefully evaluated, operated upon, and followed by the authors in a prospective clinical study. The most common thumb deformity was an adduction contracture of the thumb combined with an imbalance between the flexor and extensor mechanisms. Different surgical procedures were used depending upon the nature and degree of deformity and, above all, upon the needs of the patient. The most commonly used procedures were, first, a Z-plasty of the first web space to gain access to the contracted or spastic adductor mechanism and simultaneously to release the skin contracture and, second, a transfer of the flexor carpi radialis to the insertion of abductor pollicis longus, through a pulley constructed in the abductor pollicis brevis to gain abductor power.

Analysis of results showed that grasp was the most effective function achieved: four-fifths of the patients gained grasp; one-fifth of the patients, pulp-to-pulp pinch; three-fifths, key pinch; all retaining a mobile thumb. The poorest functional results occurred in those patients with a previously fused wrist, although this did not preclude a good result. All patients, except those with opponensplasties, were rated improved in appearance.