先天性膝关节反屈的产前超声诊断线索

Prenatal ultrasound diagnostic clues of congenital dislocation of the knee

目的探讨先天性膝关节反屈(congenital dislocation of the knee,CDK)的产前超声诊断线索。方法回顾性分析2013年1月至2018年10月郑州大学第三附属医院诊断的13例CDK病例的产前超声特征,结合基因检测结果、病理结果等进行分析。结果13例胎儿均于我院进行孕中期产前超声诊断,二维、三维超声均显示为膝关节反屈(单侧3例,双侧10例)。所有病例均伴有多发异常,主要包括足内翻(5例)、重叠指(2例)、鼻骨短小(1例)、颈后皮肤层增厚(2例)、胸廓狭小(1例)、椎体发育异常(1例)等。其中超声诊断Larsen综合征2例,先天性多发性关节挛缩症3例,窒息性胸廓发育不良1例,CDK 7例。所有胎儿引产后均证实存在CDK。已知其中3例进行染色体检查,3例染色体微阵列分析(CMA)结果未见异常,1例进一步进行了二代测序结合一代测序筛查提示FLNB基因突变,证实为Larsen综合征。结论CDK可孤立存在,也可以是多种疾病的共同表现形式,产前检出膝关节反屈时要注意是否合并其他异常,根据线索进一步行相关基因的检测,可为遗传咨询提供有价值的信息。

Objective To explore prenatal ultrasound diagnostic clues of congenital dislocation of the knee(CDK).Methods The prenatal ultrasonographic features of 13 CDK fetuses diagnosed from January 2013 to December 2018 in the Third Affiliated Hospital of Zhengzhou University were retrospectively analyzed,combined with the results of gene detections and pathological findings.Results Thirteen fetuses were diagnosed by prenatal ultrasound during the second trimester.Two-dimensional and three-dimensional ultrasound showed dislocation of the knee(unilateral in 3 cases and bilateral in 10 cases).All cases were accompanied with multiple abnormalities,including talipes(5 cases),overlapping fingers(2 cases),short nasal bone(1 case),thicken nuchal fold(1 case),narrow thorax(1 case),abnormal vertebral development(1 case),etc.Ultrasound diagnosis included Larsen syndrome in 2 cases,arthrogryosis multiplex congenital in 3 cases,asphyxiating thoracic dysplasia in 1 case,and congenital dislocation of the knee in 7 cases.CDK was confirmed in all fetuses after termination of pregnancy.Three of them were known to undergo chromosome examinations with normal chromosomal microarray analysis(CMA).One case was confirmed to be Larsen syndrome by further second-generation sequencing combined with first-generation sequencing screening,suggesting there was FLNB gene mutation.Conclusions CDK can exist isolated,and it can also be a common manifestation of various diseases.Therefore,attention should be paid to other associated abnormalities in the prenatal detection of knee flexion,and further detection of related genes can provide valuable information for genetic counseling.