Outline:   
This kind of dislocation occurs mostly in children under 4 years old. It is often caused by indirect forces. For example, when a child is being put on clothes or falls in practicing walking, the child's wrist is often injured and subluxation of head of radius may happen.

Major points for diagnosis  
1. There is a definite traumatic history of the sick arm.

2. The child cries unrestrainedly, being afraid of lifting the arm.
 
3. There is tenderness in the region of capitulum radii. The elbow joint presents a hemiflexion position with the forearm in pronation. There is no obvious swelling and deformity in the elbow.
 
4. X-ray film can reveal no disorders usually.

Treatment  
Taking the subluxation of head of right radius as an example, the parent, holding the child in his arms, sits erectly. The operator grasps the child's forearm with his right hand, puts his left thumb on the lateral part of the head of radius, and slowly rotates the forearm backward, which can generally reduce the subluxation. If this does not work, the operator should slightly perform pulling manipulation to make the elbow joint in a straightened supination position while the left thumb presses the head of radius, then flexes the child's elbow. Consequently, a slight sound entering the cotyle can be heard or felt. After the reduction is done, the sick child's pain is immediately relieved and his sick arm can move freely. Generally, no fixation is needed after the reduction. The parents are asked to avoid pulling the sick arm in the near future for fear of recurrence of dislocation.