Effects of pelvic orientation on the anteveration measurement of simulated acetabular cup / 中国组织工程研究

ABSTRACT

BACKGROUND: Acetabular cup orientation using a standard radiograph of the pelvis is quite common method to assess artificial hip replacement nowadays. Non-standardization of pelvic orientation affected accuracy of measurement results, and it is difficult to compare. OBJECTIVE: To make sure how pelvis tilting affect the anteveration of the cup and to elevate clinical accuracy and compare study comparability. METHODS: Designed a simulated acetabular cup with serial concentric circles which pass through the same polars and represent anteveration of 0°, 10°, 20°, 30°, 40°, Loaded the simulated acetabular cup at an inclination of 35°, 40°, 45°, 50°, 55° to6 cadaver pelves, Made the pelves tilt around the frontal axis and sagittal axis with 5° each time in a scope of+30°. Takestandard radiograph of the pelvis accordingly. Radiograph was photographed end frontal angle of dip was measured. RESULTS AND CONCLUSION: Pelvic tilt of about 1° causes measuring errors of anteveration 0. 61 °-0. 73°. The anteveration decreased at both acetabular cups when pelvic posterior tilt and at the acetabular cup that near the X-ray source as pelvic lateral tilt. The anteveration rose at both acetabular cups when pelvic anterior tilt and at the acetabular cup that away from the X-ray source as pelvic lateral tilt. During clinical evaluation, pelvic orientation effects on measurement results should be considered.