Evaluation of 5-Year Trends in Knee Society Scores Stratified by Comorbidities: A Prospective, Longitudinal Study.

Total knee arthroplasties (TKAs) are reliable procedures for treating end-stage knee osteoarthritis with excellent long-term outcomes. The purpose of this study was to longitudinally evaluate temporal trends of Knee Society Scores (KSS) after TKA and to identify potential demographic and comorbid factors that affect these outcomes. This prospective study evaluated 281 patients (108 men and 173 women) with a mean age of 66 years (range, 39-80 years) who underwent primary TKA (minimum follow-up 5 years). During each follow-up visit, KS objective, function, and total scores were evaluated. The effects of different demographics and comorbidities on outcomes were further analyzed using multivariate regression analysis. Following TKA, peak mean KSS were observed at 1-year follow-up (mean, 92 points), after which there was no significant difference in scores at 5 years compared with 1-year follow-up (mean, 92 points). KS function scores were observed to be unchanged from preoperative levels (mean, 53 points) and at 6 weeks (mean, 56 points). These were significantly higher at 3 months (mean, 78 points) and reached a maximum mean peak at 1 year (mean, 85 points). KS objective scores increased earlier than function scores. The demographic variables and comorbidities that demonstrated a significantly negative impact in KS function scores were increased age, female gender, higher body mass index, and several medical comorbidities including immunological and neurological disease, and neoplasm. Race was the only variable that significantly decreased the KS objective scores. KSS after TKA follow temporal trends with scores initially unchanged from preoperative levels for the objective component, but the scores increased for the functional component. All components demonstrated higher levels compared with preoperative scores by 3 months and peaked at 1-year follow-up. At 5-year follow-up, all mean KSS were unchanged relative to peak scores seen at 1 year. Various patient demographics and comorbidities could potentially have a negative influence on the KSS outcomes. Surgeons should counsel their patients that the full benefit of TKA will be perceived 1 year after surgery, and this level of improvement is likely to remain constant.

A prospective, longitudinal study of patient satisfaction following total knee arthroplasty using the Short-Form 36 (SF-36) survey stratified by various demographic and comorbid factors.

The purpose of this study was to evaluate the longitudinal variations in SF-36 physical and mental scores and the effects of demographics and comorbidities after TKA. This prospective study evaluated 108 men and 173 women who had a mean age of 66 years. All patients were followed for a minimum of five years and SF-36 physical and mental component scores were evaluated longitudinally. Physical scores steadily increased during the first year whereas mental component scores initially decreased in the first six weeks and then subsequently increased and both plateaued at one year. Demographic and social factors had a greater effect on physical component scores and comorbidities were more predictive of poor mental scores. Surgeons should counsel their patients that they will likely perceive the full benefit of TKA by one year, but in the first months may perceive worse outcomes.

A Prospective, Longitudinal Study of Patient Activity Levels Following Total Knee Arthroplasty Stratified by Demographic and Comorbid Factors.

With the marked increase in the annual number of total knee arthroplasties (TKAs) in the United States, there has been an increased interest in evaluating patient-reported outcomes. The purpose of this study was to prospectively and longitudinally evaluate temporal trends in patient activity levels following TKA and to identify potential demographic and comorbid factors that may affect these outcomes. This prospective study evaluated 281 patients, including 108 men and 173 women, who had a mean age of 66 years (39-80 years) and underwent primary TKA. All patients were followed for a minimum of 2 years. Medical comorbidities were recorded preoperatively and activity scores were evaluated at each follow-up visit. The effects of different patient demographics and systemic comorbidities on activity outcomes were further analyzed using multivariate regression analysis. Compared with preoperative levels, the activity score was observed to initially significantly decrease at 6 weeks postoperatively to below preoperative levels (9.2 vs. 8.1 points). By 3 months, scores were above preoperative levels (10.3 points), but below peak levels. A significant peak in the activity score was observed at 2-year follow-up after which there were no significant differences in scores at 5 years (11.49 vs. 11.47 points). In evaluating patient demographics and comorbidities, significant negative impact of older age, tobacco use, history of cancer, cardiovascular disease, lymphatic disease, and renal disease can be seen on activity levels. Activity scores following TKA follow a temporal trend in which scores initially drop below preoperative levels after surgery, but recover and reach a peak at 2 years postoperatively. This peak was maintained at 5-year follow-up. Surgeons should counsel their patients that they will not perceive the full benefit of a TKA until 1 to 2 years after surgery, in addition, patients may actually perceive their progress to decrease initially. Also, their improvements at 2-year follow-up are likely to remain constant for at least 5 years. However, certain demographic and comorbidities may negatively impact patient activity outcomes.

Clinical and patient-reported outcomes of primary TKA with a single-radius design.

Total knee arthroplasty (TKA) is a cost-effective procedure used to treat degenerative knee disease with excellent long-term outcomes. However, TKA has not always resulted in excellent functional and patient satisfaction outcomes, partly due to the use of prostheses that did not reproduce natural knee kinematics. Due to a paucity of reports on single-radius designs, the authors evaluated the clinical and patient-reported outcomes of primary TKA in patients who had received a single-radius prosthesis. A total of 287 TKAs from 7 centers were prospectively evaluated. Mean follow-up was 5 years, with each patient undergoing year re-evaluation. Kaplan-Meier implant survivorship was 99.7% at a final follow-up of 7 years. The total reoperation rate was 1.4%. Clinical outcomes demonstrated significant improvements in Knee Society, Short Form 36, and activity scores at a mean follow-up of 5 years. The authors believe that various features of this prosthesis may have contributed to these excellent outcomes. Further longer-term studies are necessary to better evaluate these outcomes.