股骨头缺血坏死的CT研究

目的：探讨股骨头缺血坏死（avascular necrosis of the femoral head,ANFH）CT表现及所对应的病理改变。方法：回顾性分析经病理、随访证实或有典型影像学表现的ANFH 167例共276侧髋关节的CT表现,并对其中28例行全髋关节置换术所得的33个股骨头标本的大体剖面与CT表现行逐层对照分析,并行组织病理学检查。结果：坏死股骨头病变均累及前部外上方。有标本的33个股骨头CT冠状面图均可清晰显示大体标本的坏死区、周围增生反应区和病灶外正常区,增生反应区包绕坏死区。276侧ANFH中CT诊断268侧,其余8侧CT表现正常。与正常区比较268侧股骨头坏死区呈等密度135侧、低密度112侧、不均匀高密度21侧,其中113侧于软骨下见骨折线;增生反应区呈单纯高密度硬化线175侧,硬化线内侧伴有透亮带93侧。结论：ANFH均累及股骨头前部的外上方承重区,CT能准确地显示病变形态;ANFH特征性CT表现在病变的增生反应区,其呈高密度硬化线或硬化线内侧伴有透亮带分隔坏死区和周围正常区。

A Vascular Necrosis of the Femoral Head: Correlation of CT and Pathologic Findings

Objective：To investigate the relationship between CT and pathologic findings of the avascular necrotic of the femoral head（ANFH）.Methods： The CT of 276 hip joints in 167 patients with ANFH proved by follow-up studies,pathology or typical imageologic manifestations were analyzed.Comparison among CT,gross section and pathologic findings was performed on 33 femoral heads obtained from 28 patients undergoing total hip replacement for established ANFH.Results： ANFH involved the anterosuperior aspect of the femoral head in all cases.CT coincided with gross section at the necrotic zone,proliferative zone,and extralesion zones.The proliferative zone surrounded necrotic area.ANFH was diagnosed by CT in 268 of 276 affected hips.Compared with extralesional area necrotic area appeared equidensity in 135 hips,lower density in 112 hips and higher density in 21 hips.Subchondral fracture was seen in 113 hips.The proliferative zone showed a sclerotic line in 175 hips,two parallel lines consisting of a low-density inner line adjacent to a high-density line in 93 hips.Conclusion： ANFH involved the weight-supporting zones of anterosuperior aspect of the femoral head and CT can display morphologic appearance of ANFH accurately.Characteristic CT appearances reveal in the proliferative zone,which separates necrotic area from normal area and reveals a sclerotic line or two parallel lines consisting of a low-density inner line adjacent to a high-density line.