摘要
背景:新月征是激素性股骨头坏死疾病发展过程中重要的影像学特征,反映了关节软骨和软骨下骨分离、缺损的状态,新月征的出现与疾病的中晚期和不良预后相关。但目前对激素性股骨头坏死关节软骨的具体病变特征和进展规律尚未明确。目的:观察不同时期激素性股骨头坏死标本关节软骨的病理特征,探讨病变发展规律和病理机制,并阐释新月征的形成机制,为优化保髋策略提供理论依据。方法:选取2021-2024年在广州中医药大学第一附属医院接受全髋关节置换术的激素性股骨头坏死患者的股骨头标本,根据ARCO分期分为轻度、中度和重度塌陷组,以新鲜股骨颈骨折患者的股骨头标本作对照组。所有标本经冠状面切割,取坏死区褶皱软骨面,对照组取相应区域软骨面进行苏木精-伊红染色和番红O-固绿染色观察形态学指标,免疫组化染色和Western blot检测生物标志物表达,凋亡试剂盒检测关节软骨组织凋亡水平。结果与结论:①大体观察:对照组软骨表面光滑无皱褶和增生,关节软骨与软骨下骨无分离缺损,质地坚韧;激素性股骨头坏死标本软骨表面可见明显皱褶,关节软骨与软骨下骨出现分离、缺损,按压有松弛感。②股骨头病理学观察:对照组各层软骨细胞排列整齐,软骨基质染色均匀,潮线完整连续,钙化软骨层与软骨下骨连接清晰完整,骨小梁排列整齐;激素性股骨头坏死标本的软骨细胞排列紊乱,空软骨陷窝增多,存在不同程度的基质染色缺失,潮线存在复制和缺失,钙化软骨层出现大量空腔和硬化,空腔内有肉芽组织侵入,钙化软骨与软骨下骨存在分离、缺损,软骨下骨小梁间隙存在大量增生的肉芽组织。③免疫组化染色:激素性股骨头坏死标本钙化软骨层和深层软骨Runt相关转录因子2、基质金属蛋白酶13、基质金属蛋白酶3、Ⅰ型胶原α2链阳性染色增加,软骨下骨小梁间隙和深层软骨肉芽及瘢痕组织中血管内皮生长因子A、低氧诱导因子1α、白细胞介素1β、肿瘤坏死因子α阳性染色增加。④Western blot结果显示:激素性股骨头坏死标本中Ⅱ型胶原α1链、SOX9蛋白表达下降,Runt相关转录因子2、基质金属蛋白酶13、低氧诱导因子1α、血管内皮生长因子A表达升高。⑤激素性股骨头坏死患者样本的Caspase3/7活性显著高于对照组,与塌陷程度呈正相关。⑥结果表明:激素性股骨头坏死患者关节软骨病变主要集中于坏死区周围的深层软骨和钙化软骨,软骨下骨组织坏死导致局部微环境和弹性模量改变,钙化软骨受此影响发生硬化,随着股骨头继续负重,坏死-硬化交界区应力集中发生脆性骨折,为断裂的起始部位。骨与软骨断裂导致软骨下皮质骨屏障破坏,软骨下骨小梁间隙中肉芽组织的侵入直接刺激钙化软骨和深层软骨,出现软骨细胞终末分化、凋亡、基质降解和空腔的产生,导致关节软骨修复能力下降,病变的软骨无法与软骨下骨正常嵌合,随着疾病的进展,骨与软骨最终出现广泛的分离、缺损,影像学上表现为新月征。
BACKGROUND:The crescent sign is a significant radiological feature in the progression of steroid-induced osteonecrosis of the femoral head(SIONFH),indicating the separation and defect of articular cartilage and subchondral bone.The appearance of the crescent sign is associated with the mid-to-late stages of the disease and poor prognosis.However,studies on the specific pathological characteristics and progression patterns of articular cartilage in SIONFH are limited.OBJECTIVE:To observe the pathological features of articular cartilage in SIONFH specimens at different stages,explore the underlying pathological mechanisms,and elucidate the formation mechanism of the crescent sign,providing a theoretical basis for optimizing hip-preserving strategies.METHODS:Femoral head specimens from SIONFH patients who underwent total hip replacement surgery at the First Affiliated Hospital of Guangzhou University of Chinese Medicine from 2021 to 2024 were selected.According to the ARCO staging system,the specimens were divided into mild,moderate,and severe collapse groups,with fresh femoral neck fracture specimens as the control group.All specimens were coronally sectioned,and the necrotic cartilage surface was obtained for histological staining(hematoxylin-eosin,Safranin O-fast green)and pathological assessment.Immunohistochemical staining was used to detect bone and cartilage-related protein expression,while Western blotting was employed to measure the expression levels of relevant proteins.An apoptosis kit was used to detect the level of apoptosis in articular cartilage.RESULTS AND CONCLUSION:(1)Gross observation revealed that the control group had smooth cartilage surfaces without wrinkling or proliferation,and no separation defects between articular cartilage and subchondral bone,which was strong but pliable in texture.In contrast,SIONFH specimens exhibited significant wrinkling of the cartilage surface,with separation defects between articular cartilage and subchondral bone,which felt relaxed upon palpation.(2)Pathological observation of the femoral head showed that in the control group,chondrocytes were orderly arranged,the cartilage matrix was uniformly stained,the tidemark was intact and continuous,and the calcified cartilage layer was clearly connected to the subchondral bone with orderly trabecular arrangement.In SIONFH specimens,chondrocytes were disordered,with increased empty lacunae,varying degrees of matrix staining loss,duplication and loss of the tidemark,numerous cavities and sclerosis in the calcified cartilage layer,and invasion of granulation tissue into these cavities.Separation defects were observed between calcified cartilage and subchondral bone,with abundant granulation tissue in the subchondral bone trabecular spaces.(3)Immunohistochemical analysis revealed increased positive staining for Runt-related transcription factor 2,matrix metalloproteinase 13,matrix metalloproteinase 3,type I collagen alpha 2 chain in the calcified cartilage layer and deep cartilage of SIONFH specimens.Increased positive staining for vascular endothelial growth factor A,hypoxia-inducible factor 1α,interleukin 1β,tumor necrosis factorαwas observed in the subchondral bone trabecular spaces and granulation and scar tissues of deep cartilage.(4)Western blot results showed decreased expression of type II collagenα1 chain and SOX9 proteins,and increased expression of Runt-related transcription factor 2,matrix metalloproteinase 13,hypoxia-inducible factor 1α,and vascular endothelial growth factor A in SIONFH specimens.(5)Caspase 3/7 activity was significantly higher in SIONFH specimens than the control group and was positively correlated with the degree of collapse.In conclusion,articular cartilage lesions in SIONFH patients are primarily concentrated in the deep and calcified cartilage areas surrounding the necrotic zone.Subchondral bone tissue necrosis leads to changes in the local microenvironment and elastic modulus,causing sclerosis of the calcified cartilage.As the femoral head continues to bear weight,stress concentration in the sclerotic area around the necrotic zone leads to brittle fractures,initiating the crescent sign.Fracture of bone and cartilage disrupts the subchondral cortical bone barrier,and invasion of granulation tissues into the subchondral bone trabecular spaces directly stimulates calcified and deep cartilage,resulting in terminal differentiation and apoptosis of chondrocytes,matrix degradation,and cavity formation.This leads to a decline in the repair capacity of articular cartilage.The affected cartilage cannot properly integrate with the subchondral bone,further exacerbating joint cartilage wear.As the disease progresses,extensive separation defects between bone and cartilage occur,manifesting as the crescent sign on imaging.
作者
万子艺
江梦钰
周月惠
薛宇轩
卫杨文祥
周驰
Wan Ziyi;Jiang Mengyu;Zhou Yuehui;Xue Yuxuan;Wei Yangwenxiang;Zhou Chi(Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China;Lingnan Medical Research Center,Guangzhou University of Chinese Medicine,Guangzhou 510000,Guangdong Province,China;The First Affiliated Hospital of Guangzhou University of Chinese Medicine,Guangzhou 510405,Guangdong Province,China;Guangdong Clinical Research Institute of Traditional Chinese Medicine,Guangzhou 510407,Guangdong Province,China;Maoming Hospital,Guangzhou University of Chinese Medicine,Maoming 525022,Guangdong Province,China)
出处
《中国组织工程研究》
北大核心
2026年第22期5659-5670,共12页
Chinese Journal of Tissue Engineering Research
基金
国家自然科学基金项目(82474539),项目负责人:周驰
2023年度茂名市中医药创新发展计划项目[2024-2026(2023SZY008)],项目负责人:周驰
广东省医学科学技术研究基金项目(A2024056),项目负责人:周驰。
关键词
激素性股骨头坏死
关节软骨
软骨下骨
软骨细胞
新月征
steroid-induced osteonecrosis of the femoral head
articular cartilage
subchondral bone
chondrocyte
crescent sign
