Paper 14: Sports and Everyday Life Activity After Unicondylar Knee Arthroplasty vs. Total Knee Arthroplasty

Abstract

In Germany 80.000 knee arthroplasties are performed per year, with a major increase during the last five years. The aim of this study was to evaluate sports activity, activity of leisure time and every-day life activity changes after unicondylar and total knee arthroplasty. In addition we compared activ-ity after total knee arthroplasty (TKA) versus unicondylar knee arthroplasty (UKA). Further-more we analysed subjective items like pain and knee function. In a retrospective study we used the “German PAQ-50+ Questionnaires”, which was devel-oped to analyse sports and every-day activity of elderly people by the Sports Institute, Uni-versity of Stuttgart. The questionnaire includes every-day activity like homework, gardening, occupation, activity of leisure time and sport activity in hours per week. MET-values for en-ergy use in kilocalories were applied. Additionally subjective items were evaluated with the Visual Analog Scale (VAS): For the pre- and post-operative status we collected data for pain, function of the knee, endurance, distance of walking and climbing stairs. In order to evaluate the post-op status we analyzed the level of activity, limitation and satisfaction with the surgi-cal procedure. 200 patients were included in this study, which have been operated between 2004 and 2005 (95 female, 105 male). Due to exclusion criteria 96 patients dropped out. With the rest of the patients (n=104; n=48 female, n=56 male) we performed an interview by telephone. The av-erage follow-up: 32.3 months. 51 patients (average age 66.8 y; 20f, 31 m) underwent TKA (25 PROFIX, 16 INNEX, 9 GENESIS, 1 SCORPIO type). 53 patients (average age 65.0; 28f, 25m) underwent UKA (28 ACCURIS, 19 EIUS, 5 REPICCI, 1 OXFORD type). Statistic analysis was done bivariate with unpaired t-tests. Be-cause of the explorative nature of this study we didn't do Alpha-Adjustment. Significance level was defined as p<0.05. SPSS-for Windows was used for statistical analysis. In the UKA group knee function in the VAS has increased post-op 4.6 (+/−2.9) points versus 3.3 (+/−2.8) points in the TKA group. The post-op knee function (VAS) of the UKA group is significantly higher than the knee function (VAS) of the TKA group (p=0.029). Concerning the total activity score the UKA group has a higher active score post-operatively than the TKA group, with no significant difference (UKA: 47.9 +/−21.7 h/week physical activity vs. TKA: 42.0 +/− 24.8 h/week; p=0.199). By explicit analysis of the partial activity score we did not find a significant difference between both groups. Leisure time activity: p=0.742, sport activity: p=0.100 and occupation activity: p=0.294. We also did not find any significant difference comparing the delta increase of score values from of pre- to post-op of both procedures (all data: p>0.050). The same is applicable for energy use. In both groups pain (VAS) decreases clearly, but not significantly (UKA: -3.4+/−3.4 vs. TKA: 3.7+/−2.8 points at VAS; p=0.565). Also satisfaction with the surgical procedure shows no significant difference between both groups (UKA: 8.6+/−2.1 vs. TKA: 7.9+/−2.5 points at VAS; p=0.099). The validity of this data is supported by the fact that the operative procedure of all patients was performed in the same clinic by one single surgeon (senior author) and of the structural consistency of both groups (sex, age, follow up; all data p>0.05). The comparison of UKA and TKA showed no significant differences of post-op activity, pain and satisfaction with the surgical procedure. After implantation of a unicondylar knee arthroplasty (UKA) we found significant higher subjective knee function in the VAS than after implantation of a total knee arthroplasty (TKA). This post-op outcome favours the minimally invasive surgical technique witch is less invasive and has lower risk and complication.