基于三柱结构的股骨头坏死病理和显微形态学研究

Microarchitectural features and histopathology in osteonecrosis of the femoral head based on the three pillars structure

目的比较股骨头缺血性坏死(ONFH)患者股骨头内侧、中间和外侧区域的显微结构和组织病理学差异。方法收集2015年9月至2019年10月因ONFH行全髋关节置换术的股骨头标本,共计23例(男17例,女6例),按病因分为激素性(11例)、酒精性(7例)、创伤性(3例)、原发性(2例)。所有患者均为国际骨微循环研究协会(ARCO)Ⅲ期。将股骨头坏死标本进行微计算机断层扫描(micro-CT),以主要压力骨小梁为标志,将股骨头分为内侧区、中间区和外侧区。对坏死区和交界反应区内侧、中间和外侧进行骨计量学分析;行组织学切片HE染色,比较不同区域的组织病理学差异。结果大体观察示股骨头关节面塌陷,坏死区为淡黄色致密组织,骨小梁形态紊乱;交界反应区可见肉芽组织、纤维组织以及硬化的松质骨;正常区骨小梁形态规则,方向齐整。骨计量学分析结果显示,坏死区不同区域在骨体积分数(BV/TV)、骨表面积与体积比(BS/BV)、骨小梁厚度(Tb.Th)、骨小梁间隙(Tb.Sp)、各向异性度(DA)、连通性密度(Conn.D)方面无统计学差异(P>0.05);内侧坏死区骨小梁数目(Tb.N)显著低于中间坏死区和外侧坏死区,结构模型指数(SMI)显著高于中间坏死区和外侧坏死区(P<0.05);内侧交界区BV/TV显著低于中间交界区和外侧交界区,BS/BV、SMI显著高于外侧交界区,Tb.Th显著低于外侧交界区(P<0.05),而交界反应不同区域Tb.Sp、Tb.N、DA、Conn.D无统计学差异(P>0.05)。HE染色显示,在外侧交界反应区可见炎性细胞大量浸润在纤维组织周围;与内侧交界区相比,外侧交界区的血管生成更加丰富。结论ONFH中,坏死区的显微结构相似,而交界区的显微结构存在显著区域差异,与内侧区域相比,外侧交界区表现出更致密的显微结构;在组织病理学方面,外侧交界区的血管浸润也更为丰富。

Objective To compare the microstructure and histopathology of the medial,central,and lateral regions of the femoral head in patients with osteonecrosis of the femoral head(ONFH).Methods Twenty-three femoral head samples from ONFH patients who underwent total hip arthroplasty were obtained from September 2015 to October 2019.There were 17 males and six females.The ONFH etiology was steroidinduced in 11 patients,alcohol-induced in seven patients,trauma-induced in three patients,and primary in two patients.The ONFH severity was Association Research Circulation Osseous(ARCO)stageⅢ.Micro-computed tomography was applied to evaluate the microstructure of different areas in the femoral head.According to the principal compressive trabeculae,the femoral head was divided into the medial,central,and lateral areas.Bone microstructure parameters were analyzed of these three areas of the necrotic area and the reactive interface.Histological sections were stained to compare histopathological differences in the different areas.Results Gross observation showed that the articular surface of the femoral head had collapsed,the necrotic area was light yellow,dense tissue was present,and the integrity of the trabecular bone was lost.Granulation tissue,fibrous tissue,and sclerotic cancellous bone were observed in the reactive interface.The structure of the trabecular bone in the normal area was intact.The bone volume fraction(BV/TV),bone surface/volume ratio(BS/BV),trabecular thickness(Tb.Th),trabecular separation(Tb.Sp),degree of anisotropy(DA),and connectivity density(Conn.D)in the different areas of the necrotic area displayed no significant difference(P>0.05).By contrast,the trabecular number(Tb.N)in the medial necrotic area was significantly lower than that in the central and lateral necrotic areas,and the structure model index(SMI)was significantly higher in the medial necrotic area than that in the central and lateral necrotic areas(P<0.05).The BV/TV,BS/BV,and SMI of the medial reactive interface were significantly lower than those of the central and lateral reactive interfaces,while the Tb.Th was significantly lower than that in the lateral reactive interface(P<0.05).By contrast,the Tb.Sp,Tb.N,DA,and Conn.D displayed no significant difference(P>0.05).Hematoxylin-eosin staining demonstrated abundant inflammatory cells around the fibrous tissue in the lateral reactive interface.The vasculature of the lateral reactive interface was more abundant than that in the medial reactive interface.Conclusion In ONFH,the entire necrotic area shared a similar microstructure,while the reactive interface exhibited significant area differences.The lateral reactive interface displayed a denser microstructure and more abundant vascular infiltration than the medial reactive interface.