胫骨定量CT骨密度测量法预测膝关节假体松动的研究

Quantitative CT Bone Density Measurement of Tibia to Predict Knee Prosthesis Looseness

目的探索胫骨定量CT骨密度测量对膝关节假体松动的预测效果。方法回顾性分析2019年1月至2021年1月于中国人民解放军63650部队医院行膝关节置换术患者102例,男45例,女57例;年龄57~78岁,平均(68.90±7.67)岁;左膝40例,右膝62例;身体质量指数21.26~30.01 kg/m2,平均(26.35±3.64)kg/m2。102例患者分为假体松动组与未松动组。术前与术后行双能X线吸收法(dualenergy X-ray absorptiometry,DXA)与定量CT(quantitative computed tomography,QCT)检测股骨与胫骨近端骨密度,根据T值诊断骨质疏松情况。分析两组患者一般资料、骨密度差异,使用可靠性分析观察QCT检测测量者内部一致性和测量者间一致性;观察术前及术后骨密度变化,并分析DXA和QCT的诊断准确度。结果患者均获12~24个月随访,平均(12.53±2.28)个月。TKA术后所有患者发生骨质疏松的概率显著增加。TKA术前QCT与DXA的测量结果均显示,松动组患者的骨质疏松明显多于未松动组(P<0.05);手术前后QCT的胫骨与股骨近端骨质疏松诊出率均高于DXA的骨质疏松诊出率(P<0.05);观察员一致性评价,不同观察员测量结果间具有高度一致性,总体主观误差较小。结论QCT骨密度测量法准确度高、可信度良好,全膝关节置换术前采用QCT对胫骨近端骨密度进行测量可一定程度预测术后假体松动。

Objective To investigate the effect of quantitative CT bone mineral density measurement of tibia on the prediction of knee prosthesis loosening.Methods A retrospective analysis was performed on 102 patients who underwent knee arthroplasty in the Department of Orthopaedicss of the 63650 Army Hospital of the People’s Liberation Army from January 2019 to January 2021.45 males and 57 females were included.The average age range was(68.90±7.67)years,ranging from 57 to 78 years.There were 40 cases of left knee and 62 cases of right knee.The body mass index(BMI)ranged from 21.26 to 30.01 kg/m 2,with an average of(26.35±3.64)kg/m 2.The 102 patients were divided into the loose group and the non-loose group according to whether the prosthesis was loose or not.The bone mineral density of femur and proximal tibia was measured by dualenergy X-ray absorptiometry(DXA)and quantitative computed tomography(QCT)during preoperative and postoperative follow-up.Osteoporosis was diagnosed according to T value.The general data of the two groups of patients were analyzed,and the difference of bone mineral density between the two groups before surgery was observed.Reliability analysis was used to observe the internal and inter-measurement consistency of QCT detection.The changes of bone mineral density before and after operation were observed,and the diagnostic accuracy of DXA and QCT were analyzed.Results All patients were followed up for 12~24 months,with an average of(12.53±2.28)months.The number of osteoporosis cases in all patients after TKA was significantly increased.The results of QCT and DXA before TKA showed that the osteoporosis in the loose group was significantly higher than that in the non-loose group(P<0.05).The diagnosis rate of tibia and proximal femur with QCT before and after operation was higher than that with DXA(P<0.05).The observer consistency evaluation showed that the measurement results of different observers were highly consistent and the overall subjective error was small.Conclusion QCT bone mineral density measurement is accurate and reliable.The measurement of bone mineral density of proximal tibia before total knee arthroplasty can predict the prosthesis loosening to some extent.