Diagnosing slipped capital femoral epiphysis amongst various medical specialists

Abstract

Purpose To evaluate sensitivity, specificity and accuracy of a radiographic slipped capital femoral epiphysis (SCFE)-diagnosis among medical specialists. Methods Three paediatricians, three paediatric radiologists and three paediatric orthopaedic surgeons completed two rounds of a survey of anteroposterior and frog-leg lateral radiographs of patients with a diagnosis of SCFE (25), femoroacetabular impingement (four), Legg-Calvé-Perthes (11) or no hip pathology (ten). Intra- and interobserver agreement among specialties regarding the diagnosis of a SCFE were assessed using Cohen’s kappa coefficient (κ). Diagnostic accuracy of SCFE relative to the benchmark, a combination of the radiographic diagnosis based on Klein’s line, clinical symptoms and surgical treatment, was assessed computing sensitivity, specificity and accuracy. Results Intraobserver agreement between the surveys was moderate among paediatricians (κ-range, 0.44 to 0.52), moderate to almost perfect among orthopaedic surgeons (κ-range, 0.79 to 0.88) and almost perfect among paediatric radiologists (κ-range, 0.83 to 1.00). Interobserver agreement for survey 1 and 2 was slight among paediatricians (mean κ, 0.19), substantial among orthopaedic surgeons (mean κ, 0.77) and almost perfect among paediatric radiologists (mean κ, 0.86). Sensitivity of SCFE-diagnosis was high among radiologists and orthopaedic surgeons (88% to 100% for both specialties), but lower for paediatricians (24% to 76%). Specificity was high among radiologists and orthopaedic surgeons (72% to 84%), however, variable among paediatricians (56% to 80%). Accuracy of a SCFE-diagnosis was highest in radiologists (84% to 92%), followed by orthopaedic surgeons (80% to 88%) and paediatricians (48% to 78%). Conclusion SCFE can be detected on radiographs by different medical specialties. Intra- and interobserver agreement, specificity, sensitivity and accuracy for radiographic SCFE-diagnosis amongst paediatric radiologists and orthopaedic surgeons are better than that of general paediatricians. Level of Evidence II