Widmer Karl-Heinz
Department for Orthopaedic Surgery and Traumatology, Kantonsspital Bruderholz, Bruderholz, Switzerland.
J Arthroplasty. 2004 Apr;19(3):387-90. doi: 10.1016/j.arth.2003.10.016.
Plain radiographs are the most important diagnostic means for determining the indication and following up on total hip arthroplasty. The acetabular cup position can be easily determined by applying trigonometric functions. This report presents an even simpler method. The short axis of the projected ellipse is measured and related to the total cross-section of the projected cup along the short axis. This relationship correlates with acetabular cup anteversion angles and represents an inverse sinus function. A close linear correlation is seen within the most common interval from 10 degrees to 30 degrees. Anteversion is between 23 degrees to 24 degrees when the ellipse bisects the total acetabular cross-section. This means that simply measuring the length of the short ellipse axis and the total length of the projected cross-section along the short axis provides the radiographic acetabular anteversion. Nonorthogonal projected radiographs should be corrected first.
普通X线片是确定全髋关节置换术适应症和进行随访的最重要诊断手段。通过应用三角函数可以轻松确定髋臼杯的位置。本报告介绍了一种更简单的方法。测量投影椭圆的短轴，并将其与沿短轴的投影髋臼杯的总横截面积相关联。这种关系与髋臼杯前倾角相关，呈反正弦函数。在10度至30度的最常见区间内可见密切的线性相关性。当椭圆将髋臼总横截面积平分时，前倾角在23度至24度之间。这意味着简单地测量椭圆短轴的长度和沿短轴的投影横截面积的总长度就能得出放射学上的髋臼前倾角。非正交投影X线片应首先进行校正。
