Zhang, a basketball player, accidentally poked the little finger of his right hand during an intense game. At that time, he felt some pain in his little finger and did not seem to have any other discomfort. However, in the following days, he gradually noticed that the movement of the joint on the distal side of his little finger (distal interphalangeal joint) was affected. This was manifested by the ability to bend this joint, but not to actively straighten it. When forcefully straightening all the fingers, it was evident that the last finger of the little finger was bent. As time went by, this symptom was not relieved, and at the same time, the joint gradually swelled, accompanied by vague pain and discomfort. At this point, Xiao Zhang realized that his finger was not simply poked and prodded, and when he came to the hospital, the hand surgeon diagnosed his little finger as “mallet finger” (also known as hammer finger, mallet finger), and further X-ray examination revealed that there was an avulsion fracture of the last phalanx of the little finger, which led to a rupture of the extensor tendon at the stopping point of the tendon. which led to the series of symptoms described above. Due to the long delay and the impossibility of closed restoration and fixation, Xiao Zhang underwent surgery on the advice of his doctor, and the function of his finger recovered well about eight weeks after the surgery. Experts suggest that the cause of mallet finger is mostly due to poking and prodding, after the injury should be timely to the hand surgery specialist consultation, after clarifying the injury to take the correct treatment, its functional recovery is often more ideal. If the injury is ignored, there is a risk of chronic pain and deformity, which will have an impact on work and life, and the treatment effect will also be affected after the consultation. Therefore, it is recommended that friends who love sports, if a similar situation occurs, please seek medical treatment as soon as possible to avoid delays.