Nursemaid’s Elbow (Annular Ligament Displacement)

Nursemaid’s elbow is a relatively frequent pediatric joint injury that occurs most often in children ages 6 months to 5 years. Previously described as subluxation of the radial head, nursemaid’s elbow is now referred to by the preferred and more anatomically correct term annular ligament displacement. The annular ligament normally is located just below the radial head as it passes around the proximal radius. The injury typically results from a traction force applied to a pronated arm, such as when a child is pulled up by the hand or falls suddenly when being held by the hand. This movement allows the annular ligament to slip over the head of the radius and come to rest in the radial-humeral joint between the radius and capitulum, where it becomes entrapped.

Although a traction force is the most common mechanism of this injury, often no definite history of a typical pull or fall can be obtained. Nonetheless, this injury should be suspected when a child is reported to resist moving his or her arm and is found to be holding it against the body and slightly flexed. The child usually is not in pain when left alone and the arm is not being manipulated. Parents often believe that the child’s wrist or shoulder is injured because attempts to move these joints also cause movement of the elbow …