基于影像学模型对膝内翻骨性关节炎患者前交叉韧带损伤的诊断价值

Diagnostic value of imaging model for anterior cruciate ligament injury in patients with gune varus osteoarthritis

目的探讨基于多体位X射线影像学定量参数构建的列线图模型辅助诊断膝内翻骨性关节炎(OA)患者前交叉韧带(ACL)损伤的价值。方法选择2021年1月至2023年1年于南通大学附属海安医院首次诊断为单侧膝内翻OA患者108例,其中男性62例,女性46例;年龄51~81岁,平均年龄66.6岁(标准差9.7岁);病变部位左侧54例,右侧54例。根据术前Lachman试验和MRI检查结果将其分为ACL完整组和缺陷组。所有患者接受膝关节前-后(AP)站立位、侧位和臀部到脚踝AP站立位X射线标准化检查,测量胫骨近端最大磨损点到胫骨前缘的距离比值(MWPPT%)、胫骨脊柱征(TSS)、冠状胫股半脱位(CTFS)、髋-膝-踝角(HKA)、机械近端胫骨角(mPTA)、机械外侧远端股骨角(mLDFA)和胫骨解剖轴与胫骨平台的夹角(即胫骨后倾角,PTS)。结果108例患者中,缺陷组31例和ACL完整组77例。缺陷组与完整组比较,MWPPT%、CTFS、HKA和PTS均显著增加[(58.6±6.6)%vs(46.5±6.3)%、(6.3±1.7)mm vs(5.1±1.3)mm、(10.5±3.6)°vs(7.2±2.6)°、(10.6±1.5)°vs(8.7±1.2)°。P均<0.001]。MWPPT%[比值比(OR)=1.526,95%可信区间(CI)=1.234~1.902,P<0.001]、HKA(OR=1.302,95%CI=1.112~1.756,P<0.001)和PTS(OR=2.232,95%CI=1.568~2.658,P<0.001)升高均是膝内翻OA患者ACL损伤的强效预测因子。MWPPT%、HKA和PTS的观察者间和观察者内的组内相关系数(ICC)均大于0.856,提示重复性良好。建立列线图模型后,总分220分。受试者工作特性(ROC)曲线显示,列线图模型诊断ACL损伤的曲线下面积(AUC)为0.939(95%CI=0.876~0.976,P<0.001)显著高于MWPPT%、HKA和PTS单独诊断,MWPPT%、HKA和PTS的最佳临界值分别为52.9%、8.8°和9.4°。结论术前Lachman试验和MRI检查能够有效评估术中ACL状态。根据多体位X射线测量获得的MWPPT%、HKA和PTS能够有效预测OA患者ACL损伤情况,且由此建立的列线图模型较单一指标有更高的诊断效能,具有重要的临床应用潜力。

Objective To explore the value of nomogram model based quantitative parameters of multi-position X-ray imaging for diagnosis of anterior cruciate ligament(ACL) injury in patients with genu varus osteoarthritis(OA). Methods From January2021 to January 2023, a total of 108 patients who initial diagnosed with unilateral genu varus OA were enrolled, which included 62 males and 46 females, aged 51-81 years old with mean age of 66.6 years old(standard deviation 9.7 years old).The lesion was located on the left side in 54 cases and on the right side in 54 cases. According to results of preoperative Lachman test and MRI examination, all of them were divided into ACL intact group and ACL defect group. All of them underwent X-ray standardized examination in anterior-posterior(AP) standing position, lateral position and hip-to-ankle AP standing position. The distance ratio of the maximum wear point of proximal tibia and margo anteriortibia%(MWPPT%), tibial spine sign(TSS), coronal tibiofemoral subluxation(CTFS), hip-knee-ankle angle(HKA), mechanical proximal tibial angle(mPTA), mechanical lateral distal femoral angle(mLDFA) and angle between tibial anatomical axis and tibial plateu(posterior tibial slope, PTS) were measured. Results Among 108 patients, there were 31 cases in ACL defect group, and 77 in ACL intact group. The MWPPT%, CTFS, HKA and PTS in defect group were significantly higher than those in intact group[(58.6 ±6.6) % vs(46.5 ± 6.3) %,(6.3 ± 1.7) mm vs(5.1 ± 1.3) mm,(10.5 ± 3.6)° vs(7.2 ± 2.6)°,(10.6 ± 1.5)° vs(8.7 ± 1.2)°. P <0.001]. The increased MWPPT%[odds ratio(OR) = 1.526, 95 % confidence interval(CI) = 1.234-1.902, P < 0.001], HKA(OR = 1.302, 95 % CI = 1.112-1.756, P < 0.001) and PTS(OR = 2.232, 95 % CI = 1.568-2.658, P < 0.001) were powerful predictors of ACL injury in OA varus patients. The inter-observer and intra-observer intra-class correlation coefficients(ICC) of MWPPT%, HKA and PTS were all greater than 0.856, which indicated its good repeatability. After establishment of nomogram model, the total score was 220. The receiver operating characteristic(ROC) curve showed that the area under curve(AUC) of nomogram model for diagnosing of ACL injury was 0.939(95 % CI = 0.876-0.976, P < 0.001), which was significantly higher than that of MWPPT%, HKA and PTS alone. The optimal cut-off values of MWPPT%, HKA and PTS were 52.9 %,8.8° and 9.4°, respectively. Conclusion It is demonstrated that preoperative Lachman test and MRI examination could effectively evaluate intraoperative ACL status. The MWPPT%, HKA and PTS obtained from multi-position X-ray measurement could effectively predict ACL injury in OA patients, and established nomogram model shows higher diagnostic efficiency than single index, which has important clinical application potential.