BACKGROUND: Ultrasonography of the hip performed by the Graf method is widely accepted as an important diagnostic and treatment tool for hip dysplasia. This study aims to examine the reliability and reproducibility of the interpretations of ultrasound scans by general orthopedists. METHODS: Thirteen examiners evaluated five hip ultrasounds of the same normal child. The examiners measured alpha and beta angles according to Graf. Statistical analysis was performed by variance analysis (ANOVA) and agreement was calculated and expressed as the intraclass correlation coefficient (ICC). RESULTS: The alpha angle mean was 37.32º (11.12) and the beta angle mean was 45.05º (10.49). Error of the intra-observer was 17.65 for the alpha angle and 17.63 for the beta. Error of the inter-observer was 7.68 for the alpha angle and 17.21 for the beta. ICC intra-observer was 0.18 for the alpha angle and 0.29 for the beta. ICC inter-observer was -0.02 for the alpha angle and 0.3 for the beta. CONCLUSIONS: Ultrasound of the infantile hip using the Graf method is an important tool for the assessment of developmental dysplasia of the hip, however, it must be emphasized that preciseness of interpretation requires training and frequent use.
Hip; Diagnosis; Ultrasound; Reproducibility; Reliability
