Lateral Center-edge Angle on Conventional Radiography and Computed Tomography
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Lateral center-edge angle (LCEA), originally described and validated on AP radiographs, has been used increasingly in CT-based studies, but it is unclear whether the measure is reliable and whether it correlates with that on AP radiographs.
We therefore determined: (1) the interobserver and intraobserver reliabilities of the LCEA measured on AP radiographs; (2) the interobserver and intraobserver reliabilities of the LCEA measured on CT scans; and (3) the intermodality correlation of the LCEA between CT and AP radiography.
We reviewed the AP radiographs and CT scans of 22 patients treated for slipped capital femoral epiphyses. CT scans were reoriented to a neutral pelvic tilt and inclination. Three evaluators measured the LCEA on the unaffected hip on the AP and CT coronal images that corresponded to the center of the acetabulum on the axial slice.
We found an interobserver intraclass correlation (ICC) analysis of 0.84 for the AP radiographs and 0.88 for the CT scans. The intraobserver ICC for the AP radiographs was 0.96, and for the CT scans 0.98. The intermodality ICC for the CT scans and AP radiographs was 0.79, with a lower bound of 0.61 and an upper bound of 0.87.
Our data suggest the LCEA measured on a CT scan is reliable and correlates with the LCEA on AP radiographs.
- 3.Bouttier R, Morvan J, Mazieres B, Rat AC, Ziegler LE, Fardellone P, Fautrel B, Guillemin F, Pouchot J, Roux C, Coste J, Saraux A. Reproducibility of radiographic hip measurements in adults. Joint Bone Spine. 2012 March 23. [Epub ahead of print].Google Scholar
- 4.Carroll KL, Murray KA, MacLeod LM, Hennessey TA, Woiczik MR, Roach JW. Measurement of the center edge angle and determination of the Severin classification using digital radiography, computer-assisted measurement tools, and a Severin algorithm: intraobserver and interobserver reliability revisited. J Pediatr Orthop. 2011;31:e30–e35.PubMedCrossRefGoogle Scholar
- 18.Murphy SB, Kijewski PK, Millis MB, Harless A. Acetabular dysplasia in the adolescent and young adult. Clin Orthop Related Res. 1990;261:214–223.Google Scholar
- 26.Wiberg G. Studies on dysplastic acetabula and congenital subluxation of the hip joint: With special referance to the complication of osteoarthritis. Acta Chir Scand Suppl. 1939;83(suppl 58):1–135.Google Scholar