How important is thumb function? Why do I say that preserving your child’s floating thumb is a very meaningful thing? Apart from the fact that we can visually see that children’s thumbs do not have the functions of pressing and grasping, and cannot write or twist bottle caps, babies’ pinching and grasping functions are also relatively weak, and it is difficult for babies to manipulate some large objects with one hand, for example, holding a relatively large cup of water, which is difficult for them to hold steadily. In the beginning, the floating thumb could not be retained, and only finger thumbing could be done. In the beginning, the floating thumb could not be preserved and the baby had to be finger bunionized, which means that the floating thumb is removed and the index finger is moved to the thumb position to be used as a thumb, so the baby only has four fingers, which is unacceptable to many Chinese parents who feel that having four fingers is a disability. Later, the floating thumb could be saved, using a metatarsal reconstruction. Metatarsal reconstruction can save five fingers, but it is very costly for the baby. The metatarsal reconstruction is done by removing the bone from the baby’s foot to rebuild the first metacarpal bone. Three months after the surgery, the baby cannot bear weight and can only lie down or sit down, which is very painful for the baby at the age of mobility, and also troublesome for the parents to take care of the baby. After healing, the foot will not only leave a very obvious scar, but also leave permanent damage, the baby can not run or jump strenuously from then on, which has a great impact on the baby. Nowadays, we mainly use the hemimetacarpal bone graft reconstruction technique, which not only can preserve the baby’s floating bunion, but also does not need to make any incision on the baby’s foot. Semi-metacarpal bone graft reconstruction is to take part of the bone from the second metacarpal bone of the affected hand to reconstruct the first metacarpal bone. The whole surgery is only performed on the hand, and the post-operative care is relatively simple, and the appearance will be much more beautiful, and the function can be restored to about 70%, and a lot of movements can be accomplished, which can be able to pinch some small or large objects, or to grasp some things strongly. Most importantly, the technique brings the age of surgery forward to between six months and one year, so babies can be operated on as soon as possible.