高频超声检查对急性外伤性髌骨外侧脱位的临床应用价值

Clinical value of high-frequency ultrasonography in diagnosis of acute lateral traumatic patellar dislocation

目的探讨高频超声对急性外伤性髌骨外侧脱位的诊断价值。方法高频超声扫查40例急性外伤性髌骨外侧脱位患者的患侧膝关节,并与健侧膝关节对照。分析高频超声检查结果与手术诊断的符合率和准确性。结果①急性外伤性髌骨外侧脱位时超声显示内侧髌股韧带(MPFL)撕裂、股内斜肌(VMO)血肿和/或抬升,髌骨内侧缘及股骨外侧髁关节软骨损伤,内侧副韧带(MCL)损伤及关节腔积液。收肌肌腱层面冠状切面收肌结节与VM O下缘肌纤维垂直平均间距为2.3 cm(0.7～4.2 cm),矢状切面上测量股骨内侧髁与VM O纤维间的最短间距平均为0.45 cm(0.1～2.9 cm),均比正常膝关节组平均间距增大,差异有统计学意义(P<0.01);②与手术结果比较,高频超声诊断MPFL部分撕裂的符合率、敏感度、特异度分别为92.3%、85.7%、94.7%,诊断MPFL完全撕裂的符合率、敏感度、特异度分别为90%、94.7%、85.7%。诊断关节软骨Ⅱ级损伤的符合率、敏感度、特异度分别为57.1%、36.4%、85%,高频超声诊断关节软骨Ⅲ级损伤的符合率、敏感度、特异度分别为75%、81.8%、85%,诊断关节软骨Ⅳ级损伤的符合率、敏感度、特异度分别为81.8%、100%、90.9%。结论高频超声检查能清晰显示M PFL走行情况、回声特点及毗邻结构关系,对急性外伤性髌骨外侧脱位的各种伴随损伤诊断和分级准确性较高,是一种简单可靠、快捷可重复的诊断方法。

Objective To investigate high-frequency ultrasonography manifestation and clinical value in diagnosis of acute lateral traumatic patellar dislocation（LTPD）.Methods Both knees of 40 patients with acute LTPD were examined by high-frequency ultrasonography,and compared with the high-frequency ultrasonography images of healthy knees.The diagnostic accordance rate and accuracy of high-frequency ultrasonography compared with surgical findings were analyzed.Results ①High-frequency ultrasonography can show medial patellofemoral ligament（MPFL） injury,vastus medialis obliquus（VMO） edema and/or elevation,articular cartilage injury of the medial patella and the lateral femoral condyle,medial collateral ligament（MCL） injury,and knee hemarthrosis.Elevation of the VMO muscle fibers by measuring the vertical distance from the adductor tubercle to the inferior margin of the VMO muscle in the coronal plane of the adductor tendon,and the shortest distance between the cortex of the medial femoral condyle in the sagittal plane were 2.3 cm（0.7-4.2 cm）and 0.45 cm（0.1-2.9 cm）.These measurements were significantly larger than the corresponding values in the control group.②The accordance rate,sensitivity and specificity of high-frequency ultrasonography diagnosis on partial MPFL tear were 92.3%,85.7% and 94.7% respectively.The accordance rate,sensitivity and specificity of high-frequency ultrasonography diagnosis on complete MPFL tear were 90%,94.7% and 85.7% respectively.The accordance rate,sensitivity and specificity of high-frequency ultrasonography diagnosis on grade Ⅱarticular cartilage injury were 57.1%,36.4% and 85% respectively.The accordance rate,sensitivity and specificity of high-frequency ultrasonography diagnosis on grade Ⅲ articular cartilage injury were 75%,81.8% and 85% respectively.The accordance rate,sensitivity and specificity of high-frequency ultrasonography diagnosis on grade Ⅳ articular cartilage injury were 81.8%,100% and 90.9% respectively.Conclusion High-frequency ultrasonography can clearly show MPFL as well as adjunctive structures,and can clearly and accurately show injuries after acute LTPD.High-frequency ultrasonography is an easy,reliable and rapid method in diagnosing injuries after acute LTPD.