Definition: Radial head subluxation, also known as pulling elbow, is a relatively common accidental injury in infancy, and in children under 5 years of age, forearm dislocation is easily caused by pulling. Signs and symptoms: 1. The child cries, refuses to use the affected limb, and the elbow is in a straight position, while the forearm is in a rotated forward position. 2. The child is afraid to lift and rotate the affected limb. When the elbow joint is moved passively, the child cries due to severe cracking pain. 3. There is pressure pain on the lateral side of the radial head. 4.X-ray examination may not show any abnormalities. Treatment: 1.To reset by manipulation early to prevent difficulties caused by local edema. 2.After successful reset, suspend with neck and wrist band for one week to prevent recurrence and formation of habitual dislocation. 3.Manual reset method: the operator holds the affected elbow above the wrist with one hand, the other hand with the thumb to the dorsal side of the radial head, while quickly rotate the forearm back, flex the elbow 90 ° and at the same time make the forearm and then rotate forward, at this time, if you feel a reset when the popping sound, indicating reset. The child’s crying stops and he/she can pick up objects and lift up on his/her own. If there is no popping sound, and the child keeps crying, the affected hand still dare not hold things, it may not be reset or reset late, and the local edema causes the popping sound is not obvious. Observe for a period of time and reset if necessary. Preventive care: Parents should be warned not to pull violently to avoid recurrence. Pathogenesis: Etiology and pathogenesis 1, due to the under 5 years old children radial head is not fully developed, the radial head outline is oval, the lateral posterior side is flat, the annular ligament is only a weak fibrous membrane, flaccid, very easy to cause dislocation. 2.Commonly, when young parents hold their children on the street, the children’s upper limbs are lifted up and the parents’ upper limbs are lowered, and when there are steps, the parents’ hands suddenly lift the children’s hands, or use coercive means to help the children put on clothes, and the rough pulling force can also cause radial head subluxation. 3.When the forearm is rotated forward in traction, this joint generates negative pressure, causing the annular ligament to be tense and funnel-shaped, so that it slips over the radial head, making it difficult for the forearm to rotate around. When the child walks or dresses, the forearm is pulled longitudinally and the radial head slips distally; when the original position is restored, the upper part of the annular ligament is not retracted and is stuck in the brachio-radial joint, resulting in dislocation. Diagnosis: History of upper extremity being pulled, elbow pain, no swelling and deformity of the elbow joint with flexion, and pressure pain at the radial head. negative X-ray examination. Examination methods: Physical examination is the main focus, X-ray examination may not show any abnormalities.