急性髌骨脱位后骨软骨骨折的MRI表现

MRI Features of Osteochondral Fracture after Acute Patellar Dislocation

目的:探讨急性髌骨脱位后膝关节骨软骨骨折的发生率及磁共振成像(MRI)表现。方法:回顾性阅读本研究所附属体育医院2006年10月至2010年12月的所有膝关节MRI图像,挑选出19例具有典型急性髌骨脱位MRI表现的影像资料进行分析。结果:12例(63.2%)患者17处膝关节骨软骨骨折,8例(42.1%)位于髌骨,9例(47.4%)位于股骨外侧髁,同时可见游离体11块。髌骨内侧面及中央嵴的骨软骨骨折6例,股骨外侧髁承重面或更靠后的骨软骨骨折5例。MRI能清楚显示骨软骨骨折的部位、大小、程度及游离体的位置。结论:急性髌骨脱位后骨软骨骨折常见。在髌骨面,骨软骨骨折多位于内侧面及中央嵴;而发生在股骨外侧髁承重面或更靠后的骨软骨骨折比预期的更常见。

Objective To explore the incidence and MRI features of osteochondral fracture after acute lateral dislocation of the patella.Methods MRI of 19 cases with typical acute patella dislocation was retrospectively analyzed.Results Of the 19 cases,17 osteochondral fractures were identified,including 8 patellar osteochondral fracture（42.1%）and 9 lateral femoral condyle fracture（47.4%）.Eleven loose bodies in 12 patients（63.2% were found.Six were located in the medial facet and central dome of the patella,and 5 in the weight-bearing portion or in the postero-lateral femoral condyle.The size,the osteochondral fragment,and the depth of each osteochondral fracture appeared clearly in the MRI.Conclusion Acute lateral patellar dislocation commonly accompanied with osteochondral defects.The osteochondral fracture mainly located in the medial facet and central dome of patella.Osteochondral fractures in weight-bearing portion or in the postero-lateral femoral condyle are more common than that being expected after acute patellar dislocation.