O1083: Epidemiology of Preschool Age Children Presenting to the Orthopaedic Clinic with Limping

Background: Limping in preschool-age children is a common chief complaint in the orthopedic clinic. Given the breadth of limping etiologies, there is variability in the evaluation of these patients. The objectives of our study are 1) to describe the epidemiology of preschool-age children presenting with limp, and 2) to determine predictors identifying children at risk for non-benign etiologies.

Methods: This is a retrospective study of children < 6 years old presenting to a tertiary care pediatric orthopedic clinic with a chief complaint of limping from 1/1/2019 to 12/31/2020. Subjects were identified from the electronic medical record using natural language processing. Exclusion criteria included: limp > 3 weeks, lower extremity fracture or surgery < 12 weeks, or chronic conditions affecting the lower extremity (ie. malignancy, neuromuscular disorder, sickle cell disease). Patient demographic and clinical characteristics were collected. Outcome diagnoses were classified as “benign,” “receiving advanced treatment (i.e. antibiotics, steroids, surgery),” or “inconclusive.” We calculated the frequencies of outcomes and compared them using the Chi-square test. Bivariate analyses were conducted using Student’s T-test, the Mann-Whitney U-test, or the chi-square test. We conducted a multivariable logistic regression analysis to determine predictors associated with the outcome of receiving advanced treatment vs benign/inconclusive diagnoses while controlling for patient characteristics.

Results: We identified 169 children < 6 years old with limping: 105 benign causes (62%), 27 receiving advanced treatment (16%), and 37 inconclusive diagnoses (22%). The most common diagnoses among those receiving advanced treatment were juvenile idiopathic arthritis (8/27, 30%) and Lyme disease (7/27, 26%) (Table 1). On bivariate analysis increased odds of requiring advanced treatment were identified for females (OR 2.8, 95% CI 1.20, 6.44) and presence of joint edema (OR 5.3, 95% CI 2.11, 13.47) (Table 2). Multivariate logistic regression found increased odds for receiving advanced treatment for females (OR 3.05, 95% CI 1.13, 8.24), joint edema (4.49, 95% CI 1.48, 13.61), and limp > 9 days (OR 3.43, 95% CI 1.24, 9.51).

Conclusion: The majority of preschool-age children presenting with limp had benign diagnoses. Understanding predictors for specific etiologies of limping “receiving advanced treatment” may assist in standardizing care for preschool children with limping.