Polydactyly is the most common of the congenital malformations and can coexist with syndactyly and has a genetic component. Polydactyly can be a single polydactyly or multiple polydactyly, and many cases are bilateral polydactyly. There are many types of polydactyly, which is more common on the radial side. It can be a fully developed finger with intact nails, bones and joints, tendons, nerves and blood vessels, and sometimes it is difficult to distinguish which one is normal. Treatment: 1, distal knuckle type thumb polydactyly correction: congenital duplicated thumb deformity is a common clinical hand polydactyly, manifested as thumb contracture and variable morphology. In distal segmental polydactyly of the thumb, there are two main types of polydactyly: incomplete and complete splitting of the distal phalanges of the thumb. If one side is obviously dysplastic, it can be simply removed. If the development of both fingers is equal, the treatment can be done by wedge resection according to the Bilhaut-Cloqut method to reconstruct a thumb with a shape close to normal. 2.Proximal segmental thumb polydactyly: Proximal segmental thumb polydactyly should be divided into incomplete splitting of the proximal segmental phalanges of the thumb and complete splitting of the proximal segmental phalanges. In addition, in the proximal segmental polydactyly, there can be 3 phalanges that share a joint with the main proximal segmental phalanges after incomplete splitting or complete splitting. In this type, because the short thumb adductor muscle is attached to the lateral finger, surgery is required to reconstruct the stop of the short thumb adductor muscle in addition to removing the polydactyly. 3.Metacarpal type thumb polydactyly correction: Metacarpal type thumb polydactyly is common for incomplete splitting and complete splitting of the first metacarpal. This type is often accompanied by dysplasia of the interphalangeal muscle. The interphalangeal muscle is often attached to the polydactyly and requires reconstruction of the new stop. The incomplete split metacarpal often requires orthopedic osteotomy, and after removing the excess metacarpal bone at the carpometacarpal joint, the joint capsule needs to be repaired to enhance the stability of the joint in order to better restore and preserve the appearance and function of the thumb. 4.Three phalanges thumb polydactyly: Three phalanges thumb polydactyly is less common in radial polydactyly. Since the thumb is a three-jointed phalanx, the entire thumb appears elongated in appearance. It is often accompanied by hypoplasia of the interphalangeal muscle and the thumb is deviated to the ulnar side. It is usually bilateral and has a family history of inheritance. It is usually bilateral and has a family history.