LongLifeSupport is a new application designed by orthopedic surgeons. We showed a high adherence rate to and satisfaction from home exercises in patients with KOA. The JKOM scores, SPPB scores, and knee extension muscle strength improved in the post-test. Furthermore, significant correlations were unraveled between the adherence rate and pre-test values of the JKOM and STB for LS.
This study showed high adherence rates (82.4%) to unsupervised exercises performed using the application and no correlation between adherence rate and pretest values. According to these results, this application and exercise are suitable for severe knee pain or low physical function. In a previous study, the adherence rate of home-based exercise, for which the therapist visited twice a week, in patients with KOA was 84% (21). In contrast, another study reported that the participants’ adherence rate defined as the percentage of high self-rating of knee or hip osteoarthritis to unsupervised home exercise of usual care was 44% at 13 weeks (22). Accordingly, visits by therapists influenced the adherence rates to unsupervised home exercise. However, not every patient with KOA is entitled to therapist visits for home exercise. In this study, participants without visits for supervised home exercises were offered the support of a tablet to maintain a high adherence rate. Reve et al. showed that the adherence rate of older adults using a tablet for home exercise was higher (80%) than the one when using brochures as exercise guides (59%). Moreover, older individuals exhibited low efficiency of exercise and neutral adherence. One way to strengthen self-efficacy is to set an easy and simple goal (23). In our study, almost all participants reported our application and exercise guide to be easy and of best duration. Although further studies are needed to verify our findings, we believe that our tablet exercise support will strongly contribute to increasing patients’ motivation to exercise.
In this study, 50% of the participants had not used smartphones or tablets, and 40% of them were aged > 70 years. Moreover, the CPQ scores were lower than young average scores (20). However, the satisfaction survey showed that all the participants had the impression that operating our application was easy. According to the Consumer Confidence Survey in Japan in March 2022, the penetrance ratio of smartphones in households over 70 years of age was 82% (24). This ratio increases every year. Hence, we speculate that an increasing number of elderly smartphone users will result in an increased number of users of this application.
In this study, the OA grade and sex did not significantly influence the exercise adherence rates. However, male participants tended to have lower adherence (71.6%) than did female participants (87.0%). Tuakli et al. also showed that age, OA grade, knee pain, self-reported function, quality of life, and functional performance were not factors associated with adherence to home exercise. However, they found that low income and male sex were predictive of poor adherence (9). On the other hand, in a meta-analysis, cardiac rehabilitation adherence was significantly lower in women than in men (25). Sex differences in exercise adherence remain unclear. We aim at investigating this problem in the future.
This study showed that exercise significantly improved the JKOM score, knee extension strength, and total SPPB score in patients with KOA. However, each category in the STB for LS did not improve significantly. We estimated that the reason for this was the low METs exercise. Our estimated exercise intensity was only four METs. Progression of LS reaches to limiting the independent performance of daily activities (26). Our application concept was to initially increase the exercise habits of a user with low METs and then guide them to perform exercise with high METs. We included exercises of approximately six METs in the videos of this application. We plan to conduct a study using high METs exercise videos in the future and continue investigating the use of STB for LS.
This study has few limitations. First, as this was a pilot study, the number of participants was small. The main objective of this study was to determine the adherence rate for this application. However, we observed significant differences in the JKOM score, SPPB score, and knee extension strength. Based on these results, we plan to conduct a comparative study of patients with KOA, with and without the use of this application. Second, we used the JKOM score instead of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (27). Many rehabilitation or exercise studies on KOA have used the WOMAC score. The JKOM score does not directly compare to the WOMAC score. However, the Japanese lifestyle differs from that of Western countries. The JKOM score was calculated for Japanese patients with osteoarthritis. Therefore, the JKOM score is more suitable than the WOMAC score for Japanese patients with KOA.