Nursemaid's elbow

• subluxation of the radial head
• the most common joint injury among children from 6 months to 5 years of age.
• The classic history is a child crying out in pain after traction to an outstretched arm with the hand or wrist in a pronated position, although a history of traction is not obtained in 50% of affected children.
• Even a simple stumble and fall to the ground on outstretched arms may cause this injury. Nursemaid's elbow (Figure 2) results when the annular ligament slips over the proximal aspect of the radial head, interposing itself between the radius and capitellum.
  
   
• The child who has nursemaid's elbow usually holds the affected arm close to the side and flexed at the elbow, with the forearm pronated. On examination, there is no point tenderness or swelling at the shoulder, elbow, or wrist. Any attempt at gentle supination of the forearm causes the child to cry out in pain.
• If the history and physical examination findings are compatible with radial head subluxation, no radiologic evaluation is indicated.
• The subluxation can be reduced through several simple maneuvers:
•  The most popular requires the examiner to supinate the child's wrist and hand fully until a distinct "click" is felt and often heard. The "click" is the sound of the annular ligament snapping back into place. This maneuver often is described as a three-part continuous process: 1) supination, 2) full extension at the elbow, and 3) full elbow flexion. The "click" most commonly occurs during the supination step. The examiner is advised to warn the parents that the maneuver will cause the child to cry out in pain momentarily, but if the maneuver is successful, the child should be using the arm without difficulty within 10 to 15 minutes. A second reduction attempt should be made if the first is not successful.
• Another maneuver that can be used to reduce nursemaid's elbow involves hyperpronation rather than supination as the first step, followed by extension and flexion at the elbow. Some authors have reported higher success rates with this maneuver, particularly if the supination technique has failed.
• The key point in the evaluation of a potential nursemaid's elbow is that there should be no tenderness or swelling.
• Dislocated elbow, dislocated shoulder, Salter I fracture of the distal radius, and supracondylar elbow fracture cause significant tenderness or swelling at the site of the injury. If either of these findings is present, no attempt should be made to reduce a potential subluxation; radiologic evaluation to rule out a more significant injury is warranted.
• Other clues on physical examination might point to these other injuries. A dislocated elbow is associated with deformity at the elbow and an inability to flex or extend. With a dislocated shoulder, tenderness may not be severe, but there is an obvious limitation in the range of motion. A Salter I fracture of the distal radius often causes little or no swelling, but reproducible point tenderness can be elicited over the physis. A supracondylar fracture of the elbow causes marked swelling, tenderness, and limitation in the range of motion.

References

• Joffe MD, Loiselle J. Orthopedic emergencies. In: Fleisher GR, Ludwig G, eds. Textbook of Pediatric Emergency Medicine. 4th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2000:1595-1612
• Kaplan RE, Lillis KA. Recurrent nursemaid's elbow (annular ligament displacement) treatment via telephone. Pediatrics. 2002;110:171-174
  Abstract available online, article available online for subscription or fee only.
• Macias CG, Bothner J, Wiebe R. A comparison of supination/flexion to hyperpronation in the reduction of radial head subluxations. Pediatrics. 1998;102:e10
  Electronic article available online.