髋关节置换前CT和X射线检查预测坏死股骨头的塌陷:单中心、开放性、诊断性试验

Collapsed femoral head measured by X-ray and CT before hip replacement: study protocol for a single-center, open-label and diagnostic trial

背景:确定股骨头是否发生塌陷及股骨头关节面软骨的塌陷程度,可帮助骨科医生对股骨头坏死患者选择合理的外科治疗方案。目前中国学者常根据关节面软骨塌陷小于或大于2 mm,作为选择姑息性手术和髋关节置换治疗的依据之一。但目前关于置换前股骨头塌陷的预测研究尚无统一结论。目的:试验假设髋关节置换前采用CT和X射线检查,能对坏死股骨头塌陷情况进行有效预测,其测量结果与术中截除的股骨头标本相比高度匹配。方法:研究为单中心、开放性、诊断性试验,在中国河北省,河北医科大学第三医院完成。选择置换前证实为单侧股骨头坏死并行全髋关节置换患者共86例,实验分3组,采用3种方法均测量股骨头高度变化,X射线组置换前1周采用骨盆正位(髋部健侧及患侧)X射线检查方法测量,CT组置换前1周采用双髋关节(健侧及患侧)CT扫描方法测量,标本组术中截除患侧股骨头标本采用直尺及游标卡尺等测量工具直接测量。试验的主要观察指标为3种方法检测股骨头塌陷的敏感度,次要观察指标为3种方法检测股骨头塌陷的特异度、阳性预测值、阴性预测值、阳性似然比、阴性似然比及诊断正确率;X射线及CT检测对股骨头塌陷的诊断一致性分析结果;3种方法检测的股骨头中间、内侧及外侧的高度变化;3种方法观察股骨头形态的变化。试验经中国河北省河北医科大学第三医院伦理委员会批准。研究符合世界医学会制定的《赫尔辛基宣言》的要求。参与者本人对治疗方案和过程均知情同意,并签署知情同意书。讨论:试验以髋关节置换中截除的股骨头标本为基础,结合X射线及CT对股骨头高度数据进行全方位、多角度的测量分析,以期对坏死股骨头塌陷做出准确的预测,并为进一步指导临床医生选择股骨头坏死手术方案提供影像学量化参考依据。

BACKGROUND： To determine the non-or collapsed osteonecrosis of the femoral head（ONFH） and degree of collapse, can help surgeons design reasonable treatment strategy for patients with ONFH. In China, articular cartilage collapse less than or greater than 2 mm, is a basis for choosing palliative surgery or hip replacement. However, the measurement of collapsed ONFH before replacement has not yet been confirmed. OBJECTIVE： To predict the collapse of femoral head before replacement by CT and X-ray examinations, and to compare with the intraoperative excised femoral head specimens. METHODS： This was a single-center, open-label and diagnostic trial, which was finished at the Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China. Eighty-six patients with unilateral ONFH undergoing total hip replacement were recruited, and allocated into three groups, such as X-ray, CT and specimen groups. The X-ray group underwent X-ray examination at anteroposterior pelvic（bilateral hips） at 1 week before surgery, the CT group received CT scan at bilateral hips at 1 week before surgery, and the specimen group was subjected to the removal of affected femoral head, and then directly measured using ruler and vernier caliper. Primary outcome was the sensitivity of these three methods for measuring collapsed femoral head. Secondary outcomes were the specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of these three methods for the diagnosis of collapsed femoral head and the diagnostic accuracy; the diagnostic consistence of CT and X-ray examinations; the height of the lateral, middle and external femoral head measured by three methods. The study was approved by the Ethics Committee of the Third Hospital of Hebei Medical University, China, and will be performed in accordance with the guidelines of the Declaration of Helsinki, formulated by the World Medical Association. Written informed consent will be obtained from all participants prior to the trial. DISCUSSION： In this study, the height of femoral head was measured and analyzed in all-dimensional and multi-angle manner based on intraoperative removed specimens, so as to make an accurate prediction for collapsed femoral head, thus providing imaging reference for surgeons prior to choosing an appropriate operative scheme.