摘要目的 比较X线及MRI评估Perthes病早期股骨头突出指数的差异.方法 回顾性分析2005年1月至2016年8月,38例Perthes病处于改良Waldenstr(o)m坏死期和碎裂期患儿资料,男35例,女3例;左侧21例,右侧17例;均单侧发病.其中坏死期14例,平均年龄(6.9±1.5)岁;碎裂期24例,平均年龄(7.4±1.4)岁.测量健侧和患侧X线片与MRI股骨头突出指数,即股骨头突出髋臼骨性(软骨)外缘的所有部分/股骨头骨性(软骨)外缘最大横径×100％.结果 健侧髋关节正位X线片示股骨头突出指数平均为11.6％±8.2％,患侧平均为19.3％±9.8％,两者比较差异有统计学意义(t=1 1.550,P=0.000).健侧髋关节冠状位MRI示股骨头突出指数平均为20.1％±5.5％,患侧平均为27.8％±5.8％,两者比较差异有统计学意义(t=5.172,P=0.000).X线片测量坏死期突出指数平均值16.3％±10.2％,与健侧(13.0％±9.0％)相比差异无统计学意义(t=0.369,P=0.719);碎裂期突出指数平均值21.3％±8.8％,与健侧(10.8％±1.6％)相比差异有统计学意义(t=4.756,P=0.000).MR1测量坏死期突出指数平均值是27.9％±19.6％,与健侧(21.6％±1.4％)相比差异有统计学意义(t=2.651,P=0.018);碎裂期突出指数平均值27.8％±5.4％,与健侧(19.6％±1.1％)相比差异有统计学意义(t=4.622,P=0.000).坏死期共14例,X线片有3例(21.4％),MRI有12例(85.7％)突出征阳性,差异具有统计学意义(P=0.018);碎裂期24例,X线片有17例(70.8％)、MRI有22例(91.7％)突出征阳性,差异无统计学意义(P=0.137).结论 Perthes病坏死期时X线片未观察到股骨头突出增加,而MRI可以观察到股骨头明显突出于髋臼外缘.MRI评估Perthes病早期股骨头突出指数具有更好的临床指导意义.

abstractsObjective To compare the difference of X-ray film and MRI in evaluating the degree of early femoral head protrusion of Perthes disease.Methods Data of 38 cases with unilateral modified Waldenstr(o)m necrosis and fragmentation stage from January 2005 to August 2016 were retrospectively analyzed.There were 35 males and 3 females with an average age of 7.2±1.4 years old.There are 21 cases at lefi side,and 17 at right side.14 cases were at necrosis stage,with an average age of 6.9±1.5 years.While 24 cases were at fragmentation stage,with an average age of 7.4±1.4 years old.Both side X-ray films and MRI femoral head extrusion index (X-ray:femoral head bony protruding acetabular part of the outer edge of the bones/femoral skull margin maximum diameter× 100％;MRI:outer edge of bony cartilage protrudes the part of the rim of the acetabular cartilage/the maximum transverse diameter of the cartilage of the femoral head× 100％) were collected.Results The femoral head extrusion index of healthy side was measured on X-ray films and showed an average value of 11.6％±8.2％,and the mean value of affected side was 19.3％±9.8％.The difference between the two sides was statistically significant (t=1 1.550,P=0.000).The femoral head extrusion index of the healthy side was measured on MRI and showed an average value of 20.1％±5.5％,and the mean value of affected side was 27.8％±5.8％.The difference between the two sides was statistically significant (t=5.172,P=0.000).The mean femoral head extrusion index of affected side in necrosis stage of X-ray film was 16.3％± 10.2％,but there were no significant difference compared with the healthy side (13.0％±9.0％) (t=0.369,P=0.719).The mean value of extrusion index of affected side in fragmentation stage was 21.3％±8.8％,while there was 10.8％±1.6％ at the healthy side.The difference was statistically significant (t=4.756,P=0.000).The mean extrusion index of affected side of necrosis stage in MRI was 27.9％± 19.6％,and there was significant difference compared with the healthy side (21.6％± 1.4％) (t=2.651,P=0.018).The mean extrusion index of affected side of disintegration period was 27.8％±5.4％,which was significantly lower than that of healthy side (19.6％± 1.1％).There was statistical significance (t=4.622,P=0.000).There were 17 cases (70.8％) and 22 cases (91.7％) of MRI showed positive sign,and the difference had no statistically significance (P=0.137).Conclusion No significant increasement in femoral head extrusion was observed on the X-ray at necrosis stage in Perthes disease,while MRI showed prominent femoral head extrusion at the acetabular rim.MRI evaluation for evaluating early femoral head extrusion of Perthes disease has better clinical significance.