Clinical accuracy of the posterior fat pad sign for detecting elbow fractures in children

JOMPAC - The Journal of Medicine and Palliative Care, cilt.6, sa.3, ss.271-275, 2025 (TRDizin)

Aims: To assess the diagnostic accuracy of the posterior fat pad sign (PFPS) on lateral elbow radiographs in identifying fractures

in pediatric patients with acute elbow trauma, and to evaluate whether angle measurement of PFPS enhances diagnostic

performance.

Methods: This retrospective study included patients under 18 years who presented with elbow trauma to a tertiary emergency

department between January 2022 and January 2025. All patients underwent lateral elbow radiography followed by computed

tomography (CT), which served as the reference standard. The presence of PFPS and the angle between the posterior fat pad and

humeral shaft were independently assessed by two emergency physicians blinded to CT findings. Diagnostic metrics—including

sensitivity, specificity, likelihood ratios, and misclassification rates—were calculated for both visual PFPS presence and angle-

based assessment.

Results: Of the 213 patients included, 65.3% had CT-confirmed elbow fractures. PFPS was present in 66.2% of cases and

demonstrated a sensitivity of 62.2% and specificity of 81.3% for predicting fractures. The optimal PFPS angle cutoff was 16.5°,

which yielded a sensitivity of 81.3% and specificity of 62.2%.

Conclusion: PFPS is a reliable radiographic indicator of pediatric elbow fractures. Quantitative angle measurement improves

diagnostic accuracy and may support more consistent decision-making in emergency settings where radiographic findings are

ambiguous.

Keywords: Posterior fat pad sign, pediatric elbow fracture, diagnostic accuracy