Prospective study of recurrent radial head subluxation.

OBJECTIVES

To calculate a recurrence rate for radial head subluxation (RHS) and to identify risk factors for recurrence.

DESIGN

Prospective cohort study.

SETTING

Pediatric emergency department of an urban, tertiary care children's hospital.

PATIENTS: Consecutive sample of 107 children younger than 6 years with definite (n = 94) or probable (n = 13) RHS enrolled during a 6-month period and followed up for at least 12 months.

MAIN OUTCOME MEASURE: Recurrent episodes of RHS.

RESULTS

Follow-up information was available on 86.9% (93/107) patients, with a mean +/- SD of 16.4 +/- 1.9 months (range, 12 to 20 months). Of these 93 patients, 22 (23.7%) had recurrent RHS. Among the patients who had their first episode of RHS during the study period (n = 76), those with recurrences were significantly younger than those without (21.7 +/- 9.9 months vs 29.2 +/- 13.5 months, respectively, P = .04, t test). Those 24 months or younger had a relative risk of 2.60 for one or more recurrences during the study period (95% confidence interval, 1.04 to 6.30) compared with those older than 24 months. No differences were observed in duration of follow-up, sex, elbow involved in the initial episode, or family history of RHS between those with and without recurrences.

CONCLUSIONS

Recurrent RHS occurs in nearly one fourth of patients, and those 24 months or younger are at greatest risk. Sex, family history, and the elbow involved in the initial episode are not risk factors for recurrence.