The reconstruction does not simply involve an ablation of the smaller duplication portion. The shared articular surface must be reshaped, the bones realigned, and the collateral ligaments of the joint must be reconstructed to ensure the stability of that joint, and tendons must be realigned. If these general principles are not adhered to, the thumb will otherwise have an unstable metacarpal phalangeal joint, and significant residual deformity, and major functional problems. On occasion, because of joint surface malalignment (particularly when the duplication involves a shared joint in addition to the ligament and tendon readjustments) a corrective bony osteotomy may be considered. This procedure involves actually tacking the bone and resetting its angle and may be required at the initial correction of the polydactyly. This is done to avoid any long-term misalignment of the reconstructed thumb and to minimize the risk of a residual zigzag unstable deformity to that reconstruction. While it is important to meet with the child at a young age, within a month or two of birth, the actual reconstructive surgery for polydactyly (digital duplication) will generally be performed somewhere around 9 or 10 months of age.
