Presentation of Limping Among Preschool Children in the Orthopaedic Clinic: Epidemiology and Risk Factors.

BACKGROUND

Acute limping in preschool-age children is a common chief complaint in the outpatient orthopaedic clinic. This can be a manifestation of a serious condition (eg, osteomyelitis, septic arthritis) or a benign self-resolving process. The objectives of the study are to describe the epidemiology of limping and determine predictors of children with nonbenign limp etiologies.

METHODS

This is a retrospective electronic health record (EHR) study of children younger than 6 years old presenting to an outpatient orthopaedic clinic with a chief complaint of limp from January 1, 2017 to December 31, 2021. Study subjects were identified from the EHR using natural language processing (NLP) with the term "limp" or its variations. Etiologies of limp were categorized into 3 groups: "benign/self-resolving," receiving "advanced treatment," and "inconclusive." We calculated and compared demographic and clinical characteristics of the subjects. We conducted multivariable logistic regression for the outcome of nonbenign etiologies of limping in preschool-age children, adjusting for demographic and clinical factors, and reported adjusted odds ratios (OR) and 95% CIs. We created 2 models, 1 with and 1 without the inclusion of laboratory results.

RESULTS

During the study period, 458 patients presenting with a limp met inclusion criteria. Males comprised 34%; the mean age was 2.9 (SD: 1.3) years. Limp etiologies were categorized as benign 57% (95% CI: 52, 61), advanced treatment 13% (95% CI: 10, 17), and inconclusive 30% (95% CI: 26, 34). In the multivariable model without laboratory results, increased odds of nonbenign diagnosis were associated with each additional day of limping (aOR: 1.09, 95% CI: 1.04, 1.15) and joint edema (aOR: 12.37, 95% CI: 6.24, 24.52). In the model including laboratory results, increased odds of nonbenign diagnosis were associated with joint edema (OR: 10.63, 95% CI: 3.27, 34.51) and a C-reactive protein (CRP) value >0.24 mg/dL (OR: 7.38, 95% CI: 2.37, 22.97).

CONCLUSIONS

Preschool children commonly present with benign etiologies of limp to the orthopaedic clinic. A nonbenign diagnosis is more likely to be associated with persistent symptoms, joint edema, and elevated CRP.

LEVELS OF EVIDENCE: Level II.