When a child has a floating thumb, many parents focus on the thumb and do not pay much attention to their child’s other fingers. Many parents come to the clinic only to find out that their child cannot bend the index finger. Why is there a problem with the index finger? It is simple, it is because the child’s thumb is not functional and the child has been using the index and middle fingers to hold things for a long time, the index finger will have a little problem. Therefore, it is better to operate on the floating thumb as early as possible, one, so that the function of the thumb can be established as early as possible, and two, so that the index finger can avoid being affected and unattractive. In the past, floating bunion mostly used the metatarsal reconstruction technique, which is to move the metatarsal bone on the foot to the thumb. In order to avoid fracture or metatarsal deformation of the child’s foot, the child’s foot needs to be fixed with a cast external support for about three months, during which the child’s foot cannot bear weight at all and cannot go down to the ground, but must lie down and sit, which is undoubtedly an unbearable thing for a child of active age. In addition, there is a certain chance of resorption and necrosis in metatarsal reconstruction. Because there are many problems with metatarsal reconstruction, we now use the method of metacarpal bone graft reconstruction, which means that a part of the bone is taken from the child’s second metacarpal bone to reconstruct the first metacarpal bone, and the operation time of this technique is greatly reduced, and there is no new trauma to the child’s foot, and the chance of bone resorption and necrosis is greatly reduced. The most important metacarpal bone graft reconstruction is done when the child is six months old and can be operated on as long as the child is in good health and the metacarpal bone is wide enough.