The Effects Of Infrapatellar Fat Pad On The Patellar Height And Knee Function After Total Knee Arthroplasty

Background and objective：Total knee arthroplasty for all causes of end-stage knee disease has definitecurative effect and significant, can be said to be the only effective treatment means ofa variety of end-stage knee diseases. Total knee arthroplasty can significantly improvethe function of the patients’ knee joints, the relief of knee pain when walking, correctthe varus and valgus deformity, significantly improve the patients’ quality of life. Butmany factors can influence the postoperative effect.This paper mainly studies the effect of removal or retention of the infrapatellarfat pad to the patellar height, the incidence of patellar tendon shortening and anteriorknee pain, the range of motion of the knee joint,the HSS knee functional score aftertotal knee arthroplasty.To explore whether we should remove the infrapatellar fat padin total knee arthroplasty.Research Subjects and Methods:86patients (116knees) of primary total knee arthroplasties with complete dataand good follow-up in the First Affiliated Hospital of Zhengzhou University from2010September to2012June were selected. All patients were diagnosed asosteoarthritis. And without any operation intervention to any patient preoperative.Among them, male31cases, female55cases. The average age was69.5years (55~84years old). The mean follow-up time was13.2months (12~15months).30patients were bilateral simultaneous replacement (60knees). Retention ofinfrapatellar fat pad on one side, the other side of the infrapatellar fat pad excision.56patients were unilateral replacement (56knees). Group A(59cases) was infrapatellarfat pad preserved． Group B(57cases) was infrapatellar fat pad excised. Nostatistically significant difference between the two groups of various parameterspreoperative,such as patients age, gender, body mass index, knee joint function and activity. The lateral radiographs were taken preoperative and postoperative in twogroups with the knee in a position of30°flexion, respectively measured the patellartendon length and the patellar length, to calculate the Insall-Salvati ratio. Andrecorded the incidence of patellar tendon shortening and anterior knee pain, the rangeof motion of the knee joint,the HSS knee functional score in two groups preoperativeand postoperative. Data were analyzed by SPSS17.0statistical software.Results:The preoperative and postoperative Insall-Salvati ratio showed no statisticsignificant difference in Group A(intfapatellar fat pad preserved)(t test,p>0.05) and asignificant change in Group B(infrapatellar fat pad excised)(t test,p<0.05).(t test,p>0.05). There was no statistic significant difference in the incidence of patellartendon shortening and anterior knee pain, the range of motion of the knee joint,theHSS knee functional score in two groups preoperative and postoperative.Conclusion：In total knee arthroplasty,the excision of infrapatellar fat pad would cause thepatellar height significantly decrease postoperatively,casuing low patellar andpatellar tendon shorting.But the removal or retention of infrapatellar fat pad had noobvious influence on the incidence of patellar tendon shortening and anterior kneepain, the range of motion of the knee joint,the HSS knee functional scorepostoperative.