Sugano N, Ohzono K, Nishii T, Haraguchi K, Sakai T, Ochi T
Department of Orthopaedic Surgery, Osaka University Medical School, Suita City, Japan.
Comput Aided Surg. 1998;3(6):320-4. doi: 10.1002/(SICI)1097-0150(1998)3:6<320::AID-IGS6>3.0.CO;2-O.
For precise preoperative planning in total hip arthroplasty (THA), we developed a technique of computed tomography (CT)-based computer preoperative planning and compared this technique with the single X-ray and template method generally used. The subjects of this study were 42 hips in 38 patients who underwent THA using a cementless total hip system. Preoperatively, a standard anteroposterior X-ray of the hip was taken, and conventional preoperative planning was done with a template of the total hip system. Transverse images were obtained using a helical CT scanner, and a CT-based computer preoperative plan was performed on true coronal slice images of the proximal femur reconstructed from CT data. Postoperatively, 29 hips (69%) showed good proximal fit of the femoral component to the medial endosteal line. Of the 20 hips with good proximal fit on preoperative X-ray planning, 12 hips had good proximal fit on postoperative X rays. Sensitivity and specificity of the proximal fit on X-ray templating were 41 and 23%, respectively. In 27 of 28 hips with good proximal fit on reconstructed CT images preoperatively, the postoperative X ray revealed good proximal fit. Sensitivity and specificity of the proximal fit on computer planning were 93 and 86%, respectively. Twelve hips with good proximal fit on preoperative templating, the reconstructed images, and the postoperative X ray had 20 degrees or less of combined femoral neck anteversion and external rotational contracture of the hip on the X-ray table. Eight hips with good proximal fit on preoperative templating and proximal poor fit on the reconstructed images had 17-65 degrees of combined version and rotational contracture. In 16 hips with poor proximal fit on preoperative templating and good proximal fit on the reconstructed images, the combined version and rotational contracture ranged from 17 to 69 degrees. When combined femoral neck anteversion and external rotational contracture of the hip is less than 15 degrees, the simple X-ray and template method might be sufficient for THA planning. Otherwise, the CT-based method of preoperative planning is recommended.
为了在全髋关节置换术（THA）中进行精确的术前规划，我们开发了一种基于计算机断层扫描（CT）的计算机术前规划技术，并将该技术与普遍使用的单X线和模板法进行了比较。本研究的对象是38例使用非骨水泥全髋关节系统进行THA的患者的42个髋关节。术前，拍摄髋关节标准前后位X线片，并使用全髋关节系统模板进行传统的术前规划。使用螺旋CT扫描仪获取横断图像，并在从CT数据重建的股骨近端真实冠状位切片图像上进行基于CT的计算机术前规划。术后，29个髋关节（69%）显示股骨组件与内侧骨内膜线近端匹配良好。在术前X线规划近端匹配良好的20个髋关节中，术后X线显示12个髋关节近端匹配良好。X线模板近端匹配的敏感性和特异性分别为41%和23%。术前重建CT图像近端匹配良好的28个髋关节中，27个髋关节术后X线显示近端匹配良好。计算机规划近端匹配的敏感性和特异性分别为93%和86%。术前模板、重建图像和术后X线近端匹配良好的12个髋关节在X线检查台上的股骨颈前倾角和髋关节外旋挛缩合并度数为20度或更小。术前模板近端匹配良好但重建图像近端匹配不佳的8个髋关节的合并前倾角和旋转挛缩度数为17 - 65度。术前模板近端匹配不佳但重建图像近端匹配良好的16个髋关节的合并前倾角和旋转挛缩度数为17至69度。当股骨颈前倾角和髋关节外旋挛缩合并度数小于15度时，简单的X线和模板法可能足以进行THA规划。否则，建议采用基于CT的术前规划方法。
