The objective of this study was to develop comprehensive and reliable radiation-free methods to quantify femoral and acetabular morphology using magnetic resonance imaging (MRI).Thirty-two hips [16 subjects, 6 with intra-articular hip disorder (IAHD); 10 controls] were included. A 1.5-T magnetic resonance system was used to obtain three-dimensional fat-suppressed gradient-echo images at the pelvis and distal femora. After acquisition, pelvic images were post-processed to correct for coronal, axial and sagittal rotation. Measurements performed included acetabular version (AV), femoral version (FV), lateral center-edge angle (LCEA), femoral neck angle (FNA) and alpha angle (AA) at 3, 2, 1 and 12 a.m. Two experienced raters, a musculoskeletal radiologist and an orthopedic physical therapist, and a novice rater, a research assistant, completed reliability testing. Raters measured all hips twice with minimum 2 weeks between sessions. Intra-class Correlation Coefficients (ICCs) were used to determine rater reliability; standard error of measurements was reported to estimate the reasonable limits of the expected error in the different raters’ scores.Inter-rater reliability was good to excellent for all raters for AV, FV, FNA and LCEA (ICCs: 0.82–0.98); good to excellent between experienced raters (ICCs: 0.78–0.86) and poor to good between novice and experienced raters (ICCs: 0.23–0.78) for AA. Intra-rater reliability was good to excellent for all raters for AV, FV and FNA (ICCs: 0.93–0.99); for one experienced and novice rater for LCEA (ICCs: 0.84–0.89); moderate to excellent for the experienced raters for AA (ICCs: 0.72-0.89). Intra-rater reliability was poor for the second experienced rater for LCEA (ICC: 0.56), due to a single measurement error and for the novice rater for AA (ICCs: 0.17–0.38).We described MRI methods to comprehensively assess femoral and acetabular morphology. Measurements such as AV, FV and FNA and the LCEA can be made reliably by both experienced and novice raters; however, the AA measurement was reliable only among experienced raters.

Study Design: Controlled laboratory cross-sectional Objectives: To investigate the relationship between femoral version (FV), measured by MRI (FVMRI), Craig's test and hip rotation range of motion (ROM). To determine rotation ROM values associated with FVMRI categories: excessive anteversion, normal version and retroversion. Background: Abnormal FV values are associated with hip disorders, such as osteoarthritis, structural instability, acetabular labral tears and femoroacetabular impingement. Clinical assessment of FV may allow clinician to identify the effect of bony abnormalities on hip rotation ROM to guide clinical decisions.

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