Reliability of radiographic measurement of fracture angulation in children with femoral shaft fractures.
BACKGROUND
Clinical decisions are based on x-ray measures of radiographs. However, the reliability of assessing the angular measurement of fractured femurs in children is unknown. The purpose of this study was to determine the intra- and interrater reliability of an x-ray assessment of femoral shaft fracture angulation in children.


METHODS
On 2 occasions, 3 raters evaluated 30 radiographs of children aged 4 to 10 years, 3 to 24 months after a femoral fracture. The radiographs were evaluated by an orthopedic surgeon, an orthopedic fellow and a research assistant, using a standardized methodology. Reliability was assessed with the intraclass correlation coefficient (ICC), an index of concordance that ranges from 01, where > 0.75 indicates excellent concordance.


RESULTS
The ICC for the intrarater ranged from 0.75 to 0.97. The interrater reliability ICC for anterior or posterior angulation was 0.91 (95% confidence interval [CI] 0.840.95) and for varus or valgus angulation was 0.90 (95% CI 0.790.95). A change in measurement of more than 5 degrees exceeds the variation in measurement and, therefore, can be attributed to a true shift in fracture position.


CONCLUSIONS
With specific standardized protocols, radiographic assessment of femoral fractures is reliable, irrespective of the examiner's level of experience.
Owen
Janice L
JL
Child Health Evaluative Sciences and the Department of Surgery, The Hospital for Sick Children, Toronto, Ont., Canada.
Stephens
Derek
D
Wright
James G
JG
D001837:Body Weights and Measures; D002648:Child; D002675:Child, Preschool; D002983:Clinical Competence; D015331:Cohort Studies; D005260:Female; D005264:Femoral Fractures / Q000000981:diagnostic imaging* / Q000628:therapy; D017759:Fractures, Malunited / Q000000981:diagnostic imaging* / Q000628:therapy; D006801:Humans; D008297:Male; D015588:Observer Variation; D011859:Radiography; D015203:Reproducibility of Results