Dysplastic floating thumb, a type of congenital hand deformity that severely affects the function and appearance of the thumb, can now be improved surgically. Compared to the many problems associated with reconstruction of the four fingers and metatarsals after bunionization of the signet finger, we now mainly use semimetacarpal bone graft reconstruction (SMRT floating thumb reconstruction) to treat floating finger, which is the most advanced surgical procedure at present. We will reconstruct the first metacarpal bone from a portion of bone taken from the second metacarpal bone of the child, and the whole surgery is only carried out in the child’s hand, so that it will not affect other parts of the child’s body. Some parents are worried that removing the bone from the foot may affect the child in the future, so will removing the bone from the hand also affect the child’s hand? After a long period of postoperative investigation and review of our patients, the results show that the Semi Metacarpal Bone Graft Reconstruction (SMRT) will not affect the growth and development of the second metacarpal bone, and the child’s function and appearance of the thumb will be improved when compared to the pre-operative period. More and more parents are now willing to choose this advanced surgical method to treat their children’s floating fingers.