Knee J-Sign in Recurrent Patella Dislocation: Incidence, Classification and Radiographic Characteristics
10.3969/j.issn.1000-6710.2017.10.001
- VernacularTitle:膝关节J形征在复发性髌骨脱位患者中的发病率、分度及放射学特征
- Author:
Zhe XUE
1
;
Guanyang SONG
;
Xin LIU
;
Hui ZHANG
;
Yi QIAN
;
Hua FENG
Author Information
1. 北京积水潭医院运动损伤科 北京100035
- Keywords:
recurrent patella dislocation;
patellar tracking;
knee J-sign;
classification
- From:Chinese Journal of Sports Medicine
2017;36(10):843-846
- CountryChina
- Language:Chinese
-
Abstract:
Purpose To determine the incidence,degree and radiographic characteristics of knee Jsign in recurrent patella dislocation patients.Method It was a retrospective review of a consecutive series of 59 recurrent patella dislocation patients.The knee J-sign was classified into negative (-),positive one degree(mild,l+)and positive two degree(gross,2+)based on the severity of patellar lateral translation at the extreme extension of knees with quadriceps contracted actively.The computed tomography(CT)examination at 0° extension of the knee was performed to quantify the degree of patellar lateral translation and tilt,with three CT parameters measured and calculated in axial slices:patella bisect offset index (BOI),patella trochlear-groove (PTG) distance and patella lateral tilt (PLT) angle.Results In all the 59 patients,72.9％(43/59)showed positive J-sign,27.1％(16/59)of positive one degree(1+) and 45.8％(27/59)of positive two degree(2+).All the three CT parameters increased with the severity of Jsign(P＜0.05).Conclusion Among 59 recurrent patella dislocation patients,we have found 72.9％ of positive knee J-sign.The severity of J-sign has a positive correlation with the degree of patellar lateral translation and tilt.
