Abstract
Introduction
The new Knee Society Score has been developed and validated, in part, to characterize better the expectations, components of satisfaction, and the physical activities of the younger, more diverse modern population of TKA patients. This study aims to reveal patients' activity levels' post-TKA and to determine how it contributes to their subjective evaluation of the surgery.
Methods
As part of a multi-centered and regionally diverse study sponsored by the Knee Society, the new Knee Society Score (KSS) was administered 243 patients (44% male; avg 66.4years; 56% female, avg 67.7years) following primary TKA (follow up > 1year, avg. 25mos). The new, validated KSS questionnaire consists of a traditional objective component, as well as subjective components inquiring into patient symptoms, satisfaction, expectations and activity levels as well as a survey of three physical activities that are viewed as important to the patients. Responses were analyzed as a whole group and as subgroups of male and female and as younger (<65) and older (>65).
Results
Post-TKA, knee function met or exceeded 84% of patients' expectations, with 49% of patients reporting that their knee always feels normal. While performing standard activities (eg turning, climbing stairs), the majority of patients (78%) experienced few symptoms referable to the knee. Fewer (47%) report that they remain asymptomatic while performing more demanding (‘advanced’) activities (eg squatting, running). Distance walking (52%), swimming (28%) and stationary biking (25%) were among activities that were most commonly selected as personally important. Activities such as golf (Male 39%; Female 6%; p<0.001) and road cycling (Male 19%; Female 4%; p<0.001) were important to more men than women, whereas for gardening (Female 44%; Male 32%; p=0.001) and stretching (Female 44%; Male 16%; p<0.001) the gender preference was reversed. Overall, 24% of patients experienced severe symptoms when performing at least one of their most important activities. Older patients experienced symptoms more than younger patients (26% vs 21%; p<0.01). As a whole, 93% of patients reported that they were satisfied with their knee post-operatively. However, satisfaction with TKA decreased significantly among patients who experienced severe or debilitating symptoms during of their most important activities, (at least one activity: 78% satisfied; p<0.001; during all 3 activities: 50%; p<0.001).
Discussion
The New Knee Society Scoring System provides sufficient flexibility and scope to capture the diverse lifestyles and activities of contemporary TKR patients. Data collected by this assessment tool allow surgeons and affiliated personnel to appreciate differences in the priorities of individual patients and the interplay between function, expectation, symptoms, and satisfaction after TKR. A resounding conclusion of this new multi-dimensional analysis is that a critical factor in many patients' assessment of the value of this procedure is their restored ability to perform activities that they personally consider important.
