The consistency between measurements of the femoral neck anteversion angle in DDH on three-dimensional CT and MRI.

Background: Three-dimensional computed tomography (3D CT) has been regarded by some investigators as the gold standard for measurements of the femoral neck anteversion angle (FNA) in developmental dysplasia of the hip (DDH), although a simple and reliable imaging method using a non-ionizing technique is needed.

Purpose: To determine the consistency between measurements of the FNA in DDH using 3D CT and magnetic resonance imaging (MRI) and to estimate the precision, reliability, and reproducibility of MRI for the measurement of the FNA and assess whether MRI could replace 3D CT.

Material And Methods: 3D CT and MRI were used to measure the FNA in 22 patients, including 18 girls and four boys, with a mean age of 3 years (age range, 1-7 years).