Imaging Measurements And Influencing Factors Of Non-uniform Settlement Joint Line In Patients With Knee Osteoarthritis

Background:With the aggravation of population aging,the incidence of knee osteoarthritis(KOA)is increasing gradually,and it has become one of the factors that affect the quality of life and social economic pressure.With the development and application of surgical technique,total knee arthroplasty(TKA)has become a routine operation in patients with intermediate and advanced of KOA.The restoration of anatomical position of knee joint line during operation is an important guarantee of postoperative joint function and life span of prosthesis.At present,the research at home and abroad mainly focuses on the anatomic markers around the normal knee joint.There is no report on the changes of knee joint line and influencing factors in Chinese with KOA.Objective:Through measuring the X-ray basic parameters of patients with knee osteoarthritis(KOA),this study aims to explore the rule and influencing factors of knee joint line remodeling as well as non-uniform settlement.And its influence on the force line of the lower extremities.Methods:148 patients(totally 192 knees),including 50 males(59 knees)and 98 females(133 knees)are involved in the study.They age from 41 to 81,with the mean age of 64.3.The patients were divided into Group A and Group B by age.All knee joints were graded by K-L grade.The distance between the knee anatomical landmarks and the knee joint,the altitude of femoral condyle and tibial platform were frist measured and then analyzed on the standard knee anteroposterior radiograph.Results:The distances from femoral adductor tnbercle and the apex of fibular head to knee line were respectively 49.59 ± 4.76mm(ATJL)and 17.37 ± 4.72 mm(FHJL).The altitudes of medial and lateral femoral condyle,medial and lateral tibial plateau were respectively 49.04 ± 4.83(MFCA),46.78 ± 5.80 mm(LFCA),4.21 ± 5.20 mm(MTPA)and 9.12 ± 4.13 mm(LTPA).The femoral width(FW)was 92.64 ± 7.34 mm,which was positively correlated with ATJL(r=0.651,P< 0.001).There were statistically significant differences in male and female(P <0.05)among FW,ATJL,MFCA,LFCA.There was statistic differences in MTPA between groups(t=2.195,P=0.003).According to the K-L grade,there exsisted statistically significant difference between groups(F=4.082,P=0.003),and MTPA was negatively correlated with the K-L grade(r=-0.241,P=0.001).Conclusion:The MTPA was negatively correlated with the severity of KOA,thus can be used to evaluate the severity of KOA.For patients with KOA,ATJL and FW have correlation with each other.With the increase of age,the altitude of the MFCA?LFCA?LPTA did not change,the MTPA significantly lowered,which suggested that the tibial platform are non-uniform settlement with the age.Resulting in reconstruction of the knee joint,knee joint non-uniform settlement and varus malalignment of the lower extremity.