Clinical Follow-up Study Of Rotation Of Femoral Component Affects The Subjective Scores Of The KSS After TKA

Objective: To investigate the effect of rotational alignment of the femoral conponment on evaluation of outcomes using The 2011 KSS.Methods:C linical follow-up study on 158 patient 198 cases of knee joint,(including 54 males 68 cases of knee joint,104 females 130 cases of knee joint),who had primary posterior cruciate ligament-substituting(PS)TKA in our hospital five years ago.1.CT test the condylar twist angle(C TA): Patients lay on the scanner table,with both knees extension to keep a neutral position.CT scan perpendicularly the long axis of the involved knee femoral machinery,slice thickness 1.0mm,epicondyle of femur and posterior femoral condyle clearly presenting on the axial scan.Select appropriate levels to measure CTA---angel between CTEA,C linical transepicondylar axis and PCL,posterior condylar line.Test three thimes to get the average value.The degree of C TA is the angel degree of the rotational alignment of the femoral components.2.Groups: Mark internal rotation with minus,and external rotation with plus.Then classify the results into 3 groups---A(from-3°to 3°),B external group(external rotation >3°),and C internal group(internal rotation>3°).To those patient with two knee replacement,measure knees separately and classify into the right group.Group A: 104 cases,the absolute value of CTA 1.39±0.73 degree.Group B: 73 cases,external rotation 5.23±1.87 degree.Group C :21 cases internal rotation 4.8±2.13 degree.There was no statistically significant in age,gender composition,BMI(body mass index)and knee side.3.The Knee Society Score(2011 version)including: 1.patient satisfaction(5 items,total 40 points);2.Patient expectation(3 items,total 15 points);3.Function actions(total 100 points),including:walking and standing(5 items,total 30 points),standard activities(6items,total 30 points),advanced activities(5items,total 25 points),and discretionary knee activities(3items,total 15 points).We do the subjective scores following KSS 2011 version.All the data are completed by the same person,and checked two times by another one.4.Statistical analysis is done folowing SPSS16.0,the unit of measurement expressing with mean and standard deviation,acceptance standard P=0.05?We do one-way ANOVA separately for patient satisfaction,patient expectation,function actions,walking and standing,standard activities,advanced activities,and discretionary knee activities of group A,B and C.Result:Patients,who had primary posterior cruciate ligament-substituting(PS)TKA 5 years ago,all achieve high scores in patient satisfaction and patient expectation,and shows no clear statistically significant.But there is statistical significance in patients with function action,as the following,Group A(84.65±5.18)>Group B(80.19±5.04)>Group C(75.33±6.08).Then we analyze items of function actions one by one.and find there is no obviously difference in walking and standing.But there is statistical significance in standard activities,advanced activities and discretionary knee activities,and the scores are coincident---Group A >Group B >Group C.Conclusion: TKA total knee arthroplasty is a very mature operation for the treatment of terminal-stage knee joint disorders,which can effectively solve knee pain issue,rebuild knee function,and achieve satisfactory curative effect.Good rotation of femoral component is a necessary condition for patients' functional recovery,especially for hose highly knee joint function demanding activities.Malrotations of the femoral component should be avoided during operation at all possible,especially internal rotation of the femoral component.