How reliable are radiographic measures of the pediatric elbow? Measurement and comparison of four parameters in healthy children’s elbow

The reproducibility of radiographic parameters used to assess pediatric supracondylar fracture reduction, including Baumann angle, lateral capitellohumeral angle (LCHA), carrying angle, and anterior humeral line (AHL) crossing the capitellum, was evaluated. Two observers undertook a total of 2368 measures on 148 elbow radiographs from 107 patients aged 0-12 years. The observers, who were blinded to their own measurements and each other's measurements, performed the measurements twice with a 1-month interval using an electronic goniometer. The average value and reliability of the measurements were evaluated. Intraobserver and interobserver reliability were determined using intraclass correlation coefficients (ICCs). The mean LCHA of the 148 elbow population was 52.4° (range: 27-74°), the mean Baumann angle was 71.5° (range: 54-90°), and the mean carrying angle was 18° (range: 5-37°). 80% of the AHL was in the middle third of the capitellum. The ICCs for interobserver reliability were moderate to good for Baumann angle 0.71-0.78, for LCHA 0.72-0.72, for carrying angle 0.83-0.85, and for AHL 0.89-0.90. The ICCs for intraobserver reliability were moderate to excellent for Baumann angle 0.93-0.86, for LCHA 0.91-0.81, for carrying angle 0.71-0.92, and for AHL 0.94-0.90. This study demonstrated that Baumann angle, LCHA, carrying angle, and AHL are reliable measuring methods, with normal values reported in the Turkish population.