I never realized how fragile a child’s joints are until the day after New Year’s. I was in the living room playing with my son when he suddenly started screaming. I had no idea what was wrong, only that his right arm wasn’t moving. I rushed him to the ER as quickly as I could. It turned out he had rolled over in an odd way and dislocated his elbow. I’ve since learned this type of injury can happen in many different ways. Before then, I thought a joint could only dislocate with a lot of force. But a child under four can dislocate an arm just by pulling away from a parent. I urge parents to find other ways to guide their young children, and if nothing else works, simply pick them up.

Nursemaid’s Elbow

Nursemaid’s elbow is a common injury that is seen most often in children between the ages of 1-3 years. Usually, the child has had an incident in which the extended arm was pulled. Most commonly it occurs when a child is falling and the individual holding the hand doesn’t let go. Another common mechanism is when the child is swinging while being held by the hands. Occasionally, the injury occurs after a fall. 

Anatomy

Nursemaids elbow is an interposition of the annular ligament into the radial-humerus joint. The annular ligament normally passes around the proximal radius just below the radial head. With traction on the extended arm, the annular ligament slides over the head of the radius into the joint space and becomes entrapped. 

Epidemiology

1. Nursemaid’s elbow is more common in girls than boys and more often on the left side.
2. Usually between 1-3 years of age and rare after age 4.

Clinical presentation

1. There is usually a history of axial traction. 
2. have been reports of infants < 6 months old with a history of not using arm after rolling over and their arms getting caught.
3. At times, there is no history of axial traction or none was observed.
4. Child will not use the arm and holds the arm slightly flexed and pronated.
5. May elicit tenderness over the elbow joint but there is no swelling, redness, warmth, abrasions, or ecchymosis.

Diagnosis

1. The diagnosis is by history and Radiograph examination is usually not necessary and are normal in most instances. Often during the taking of the x-ray, the subluxation is reduced when the technician positions the arm on the plate.

Treatment

1. While supporting the radial head, the forearm is supinated or pronated and flexed at the same time. A “click” will be heard or felt. 
2. After the “reduction”, the child will immediately use the arm. There is no indication for immobilization and rarely are analgesics necessary. 
3. Unless the child doesn’t start to use the arm, follow-up is unnecessary.
4. There is a relatively high incidence of recurrence. Parents should be made aware of this and the mechanism of injury should be explained. It may be useful to teach the parents how to “reduce” the dislocation at home. 
5. There are no known sequelae.

References

1. Choung, Walter, and Heinrich,Stephen. Acute Annunlar Ligament Interposition into the Radiocapitellar Joint in Children (Nursemaid’s Elbow). Journal of Pediatric Orthopedics. Vol. 15, No.4 1995
2. Wander, Hellerstein, and Ballock. Nursemaid’s Elbow, Pulling out the Diagnosis  Contemporary Pediatrics June 2000