CPT® Code 26550

Pollicization of a digit is a surgical procedure that involves the transfer of one of the fingers, most commonly the index finger, to the anatomical position of the thumb. This procedure is typically indicated for patients who have experienced a traumatic amputation of the thumb, or for those who have congenital conditions resulting in the absence or underdevelopment (hypoplasia) of the thumb. The surgical technique begins with an incision made over the metacarpal bone, which is the long bone in the hand that supports the thumb and fingers. During the procedure, careful dissection of the soft tissues is performed, with particular attention to preserving the neurovascular structures that supply the hand. The midportion and base of the index finger's metacarpal bone are excised, while the metacarpal head is preserved. This preservation is crucial as the metacarpophalangeal joint of the index finger will serve as the new carpometacarpal joint for the reconstructed thumb, and the metacarpal head will take on the role of the trapezium bone, which is the bone that articulates with the thumb. Following the excision, the index finger is rotated into the position of the thumb. To enhance the functionality of the new thumb, the lateral slips of the dorsal aponeurosis are mobilized, and the two interossei muscles of the index finger are detached and fixed in a shortened position to the lateral slips on both sides of the newly positioned thumb. This rearrangement of the interossei muscles is designed to improve the thumb's function, allowing for full or nearly full opposition and abduction, which are essential movements for grasping and pinching. Additionally, this technique helps to create a thenar eminence, which is the fleshy prominence at the base of the thumb, contributing to a more cosmetically acceptable appearance of the new thumb. Finally, a dorsoradial skin flap is created and rotated to cover the gap that exists between the newly formed thumb and the adjacent middle finger, completing the reconstruction.