目的 测量正常及不同ARCO分期 条件下坏死股骨头软骨T2 map值的变化， 评估其临床应用价值。方法 搜集不同 ARCO分期坏死股骨头(ARCOI期、ARCOII 期、ARCOIII期)及正常股骨头各20例，年 龄20-50岁，所有病例均行MRI检查。测量 各期坏死及正常股骨头软骨的T2 map值的 定量学数据。所有选取坏死及正常研究对 象均排除骨质疏松及其他影响观察的基础 性疾病。结果 随着病情进展，坏死股骨 头ARCO分期越高，软骨T2 map值越高，软 骨的损害也就越明显；经LSD检验分析提 示坏死股骨头ARCOIII期软骨与正常股骨 头、ARCOI期、ARCOII期软骨T2 map值之 间的差异有统计学意义，P值小于0.05。 结论 正常股骨头软骨的T2 map的数值大 约可界定为(49.39±8.158)之间，临床上 可将此区间值作为可能性参考标准；随着 股骨头坏死病程的进展，股骨头软骨损伤 变性的程度有逐渐加重趋势。

Objective To investigate the values of quantitative parameters of T2 map of cartilage in different ARCO stage of the femoral head necrosis. Methods Different Arco stage avascular necrosis of the femoral head (ARCO I, ARCOII, ARCOIII period) and normal femoral head with 20 cases in each were enrolled in this study from age 20 to50, all case of illness all MRI check. Data quantitative calculation of each period of femoral head necrosis and normal cartilage of femoral head T2 map value. All the selected necrosis and normal subjects were excluded on the basis of observation of disease osteoporosis and other effects. Results Along with the progress of the disease, avascular necrosis of the femoral head ARCO stage is high, the more serious illness, cartilage T2 map value higher, cartilage damage and also more obvious.The LSD test analysis showed that between avascular necrosis of the femoral head ARCOIII period cartilage and normal femoral head, ARCOI, ARCOII period cartilage T2 map values had significant difference, P values less than 0.05. Conclusion Normal T2 map values of the cartilage of the femoral head can be defined as about (49.39±8.158), the clinical possibility can be the interval value as the reference standard, as with the progress of the ARCO I-III, the extent of the femoral head cartilage damage degeneration has a gradually increasing trend.