MRI定量测量内侧半月板外凸值与内侧半月板损伤模式及软骨损伤的相关性

Correlation of MRI quantitative measurement of medial meniscus extrusion and medial meniscus injury pattern with cartilage damage

背景:膝关节内侧半月板在损伤时可在MR影像上观察到超出胫骨平台边缘的外凸,其外凸值的大小是否与内侧半月板损伤的模式相关、是否与膝关节内侧间室软骨损伤程度相关值得探讨。目的:在MRI下量化测量内侧半月板外凸值,并分析其影响因素,以及外凸值大小与内侧半月板损伤模式、内侧间室的软骨损伤程度是否有相关性。方法:选择117例因膝关节半月板后角损伤就诊于安徽医科大学第一附属医院,并接受了膝关节MRI扫描检查和膝关节镜半月板手术的患者。MRI测量每例患者的半月板外凸值,从病历中录入每例患者的体质量指数、是否因急性创伤就诊、关节镜下证实的半月板损伤模式和内侧间室的软骨损伤等级等信息,分析半月板外凸值大小与上述因素的相关性。结果与结论:①病史中存在可明确回忆的急性创伤患者组31例(26.5%),无明确回忆的急性创伤患者组86例(73.5%),两组半月板外凸值比较差异有显著性意义(P=0.001);②低体质量指数组(体质量指数≤25 kg/m^(2)) 56例(47.9%),高体质量指数组(体质量指数> 25 kg/m^(2)) 61例(52.1%),两组半月板外凸值比较差异有显著性意义(P=0.008);③按照半月板损伤部位分为半月板后体部损伤组60例(51.2%)、后角损伤组37例(31.6%),后根断裂组20例(17.1%),各组间半月板外凸值比较差异有显著性意义(P=0.000);④按照关节镜下证实的损伤情况,将非内侧半月板后根断裂的患者分为半月板复合裂组(n=49)和非复合裂组(n=48),两组半月板外凸值比较差异有显著性意义(P=0.000);⑤半月板外凸值预测内侧间室中重度软骨损伤和内侧半月板后根断裂受试者工作特征曲线下面积分别为0.794和0.942;⑥提示半月板外凸值的大小与患者病程中有无急性创伤、患者体质量指数和患者内侧半月板损伤模式相关,且半月板外凸值对内侧半月板后根断裂有较好的预测价值。

BACKGROUND:The medial meniscus extrusion beyond the edge of the tibial plateau can be observed on MR images of the medial meniscus of the knee joint during injury.It is worth explo ring whether the external protuberance is related to the mode of medial meniscus injury and the degree of medial interventricular cartilage injury of the knee joint.OBJECTIVE:To quantitatively measure the extrusion of medial meniscus under magnetic resonance imaging,and to study the facto rs affecting the value of medial meniscus extrusion,and whether it is related to the injury mode of medial meniscus and the degree of cartilage injury in medial compartment.METHODS:In this study,117 patients diagnosed as knee meniscus posterior horn injury by sports injury in First Affiliated Hos pital of Anhui Medical University were selected.They underwent knee joint MRI scan and knee arthroscopic meniscus surgery.The meniscus extrusion value(medial meniscus extrusion) was measured under MRI in each patient.The body mass index of each patient,whether due to acute injury,the mode of meniscus injury confirmed by arthroscopy and the grade of cartilage injury in the medial compartment were recorded from the medical reco rd,and the correlation between the meniscus extrusion value and the above-mentioned fa ctors was analyzed.RESULTS AND CONCLUSION:(1) There were 31(26.5%) acute injury patients with definite recall,86(73.5%) acute injury patients with no clear recall;there was a significant difference in the meniscus extrusion value between the two groups(P=0.001).(2) There were 56(47.9%) patients with low body mass index(body mass index ≤ 25 kg/m^(2)) and 61 patients(52.1%) with high body mass index(body mass index> 25 kg/m^(2));there was a significant difference in the meniscus extrusion value between the two groups(P=0.008).(3) According to the site of meniscus injury,there were meniscus posterior body injury group(60 cases,51.2%),posterior horn injury group(37 cases,31.6%),and poste rior root fracture group(20 cases,17.1%);there was a significant difference in the meniscus extrusion value between the two groups(P=0.000).(4) According to the injury confirmed by arthroscopy,patients with non-medial meniscus poste rior root rupture were divided into compound meniscus fracture group(n=49) and non-compound meniscus fracture group(n=48);there was a significant difference in the meniscus extrusion value between the two groups(P=0.000).(5) The areas under receiver operating chara cteristic curve of moderate and severe cartilage injury in medial compartment and medial meniscus posterior root tearing predicted by medial meniscus extrusion were 0.794 and 0.942,respectively.(6) It is indicated that the size of medial meniscus extrusion reflects the presence or absence of acute trauma in the patient s disease course,their body mass index,and pattern of medial meniscus injury.Medial meniscus extrusion has a good predictive value for medial meniscus posterior root rupture.