髌股关节发育不良对髌骨脱位磁共振成像表现的影响

Magnetic resonance imaging features of dysplasia of patellofemoral joint after patellar dislocation

背景:当存在髌股关节发育不良时,髌骨脱位的损伤程度较轻,因此更加依赖影像学诊断。目的:比较髌股关节发育不良患者和髌股关节发育正常患者髌骨脱位时磁共振成像(MRI)表现的异同。方法:回顾性分析54例经临床证实的髌骨脱位患者的MRI影像学资料。髌股关节发育不良患者32例,髌股关节发育正常患者22例。记录患者MRI中髌骨内侧骨挫伤或撕脱骨折、髌骨关节面骨软骨骨折、股骨外侧髁外侧部骨挫伤、髌股内侧支持带撕裂等情况。结果:髌股关节发育不良组的32例患者中,髌骨内缘骨折12例,内侧支持带损伤10例,髌骨软骨损伤7例,股骨外髁骨挫伤18例;髌股关节发育正常组的22例患者中,髌骨内缘骨折8例,内侧支持带损伤14例,髌骨软骨损伤14例,股骨外髁骨挫伤14例。两组在内侧支持带损伤和髌骨内缘骨折上有显著统计学差异(P<0.05)。结论:MRI可以较好地诊断髌骨脱位。当髌股关节发育不良时,内侧支持带损伤和髌骨内缘骨折的发生率降低。

Background：When patellofemoral joint is dysplastic, the injury caused by patellar dislocation is slighter than that of normal patellofemoral joint. Therefore, magnetic resonance imaging （MRI） is very important for dignosis of dysplasia of patello-femoral joint after patellar dislocation. Objective：To explore MRI features of dysplasia of patellofemoral joint after patellar dislocation. Methods：A retrospective study was conducted in 54 patients with patellar dislocation. There were 32 patients with dysplasia of patellofemoral joint, and 22 patients with normal patellofemoral joint. MRI features were investigated, including medial patellar fracture, medial patellar retinaculum injury, osteochondral injury of patellar, bone contusion of lateral femoral con-dyle. Results：In the group of dysplasia of patellofemoral joint, there were 12 cases of medial patellar fracture, 10 cases of medial patellar retinaculum injury, 7 cases of osteochondral injury of patellar, and 18 cases of bone contusion of laterl femoral con-dyle. In the group of normal patellofemoral joint, there were 8 cases of medial patellar fracture, 14 cases of medial patellar retinaculum injury, 14 cases of osteochondral injury of patellar, and 14 cases of bone contusion of laterl femoral condyle. There were significant differences in medial patellar retinaculum injury and medial patellar fracture between two groups （P〈0.05）. Conclusions：Patellar dislocation is diagnosed effectively by MRI. The incidence of medial patellar retinaculum injury and medial patellar fracture presented by MRI will lower when patellofemoral joint is dysplastic.