Parental questionnaire study showed that annular ligament displacement was common in three-year-old children and almost a half had reoccurring episodes.

Aim: This study sought to determine the incidence of annular ligament displacement (ALD), also known as nursemaid's elbow, in the first 3 years of life.

Methods: A questionnaire was sent to 1098 families between August 2014 and July 2015 before their child attended a routine health check at 3 years of age in Izumo, Shimane prefecture, Japan. The questionnaire included a brief description about ALD, the age when ALD occurred and how the condition was managed.

Results: We received 784 (71.4%) responses and these showed that 61 (7.8%) children had a history of ALD and 31 (51%) were girls. The incidence was 2.6%, calculated by multiplying the number of children by the 3-year observation period. The mean and median ages of the first ALD occurrence were both 25 months. In addition, 28 (46%) children with ALD had a recurrence and the mean number of ALD episodes was 1.8 (range 1-5). The total number of ALD episodes was 108, and of these, 33 (30%) were seen at the hospital emergency department and 17 (16%) spontaneously resolved.

Conclusion: This study confirmed that ALD was a common occurrence in 3-year-old children and that there was a high rate of recurrence.