The straightened finger position is the most common when casting a fracture of the fourth metacarpal of the right hand, and it is not good to talk about it. The casting method of the fourth metacarpal fracture of the right hand is generally simple, mostly four fingers are straightened, the thumb is extended to the outside, the plaster bandage is fixed in the metacarpophalangeal joint, the proximal end passes through the carpal joint, and the plaster bandage wraps around the wrist and the palm of the hand, with a moderate degree of tightness. After casting a fracture of the fourth metacarpal of the right hand, it is important to take good care of it, observing the drying time, tightness, time of cast replacement, peripheral blood circulation, and so on. The immobilized joints such as shoulder joint, elbow joint and fingers need appropriate exercise, which is not only conducive to the recovery of the fracture, but also to the recovery of the function of the whole limb. The specific position of the fourth metacarpal fracture plaster fixation should be combined with the specific conditions of the fracture by the doctor to do detailed judgment, not completely set in stone.