学位論文内容の要旨（ Summary of dissertation）

博士の専攻分野の名称

博士（医 学）（Degree conferred: Doctor of Philosophy）

氏 名

黄 于 庭

（Name of recipient: Yu-Ting, Huang）

学 位 論 文 題 名（Title of dissertation）

Effectiveness of the video-based home exercise on clinical and radiographic outcomes for
subjects with osteoarthritis of the knee.
(変形性膝関節症症例に対するビデオプログラムを用いたホームエクササイズの臨床的および X 線学的効果の検討)【Background and Objectives】 Osteoarthritis (OA) of the knee is a disease that limits a patient’s activities
of daily living ADL and affects health-related quality of life (QOL). Previous randomized controlled studies
and systematic reviews conclude that exercise therapy has beneficial effects on symptoms physical function
and health status of the population with knee OA. However, these effects declined over time and finallydisappear. There is a possibility that the use of a home exercise video could enhance adherence toprescribed exercise program. The objective of the present study was to test the hypothesis that video-based
home exercise could enhance adherence exercise and improvement in pain, physical function and QOL inpatients with knee OA, and also prevent radiographic progression of knee OA compared with conventional
home exercise without video media.
【Methods】A total of 107 subjects with radiographic evidence of OA were randomized to a video-based
exercise group and control group. The study was approved by the medical ethics committee of Hokkaido
University School of Medicine. Subjects in the video-based exercise group received an exercise video andused it during home exercise. Subjects in the control group initially received detailed instruction of aquadriceps exercise. To evaluate adherence to home exercise, we collected the number of days when thesubject performed the allocated prescribed home exercise from the custom-designed diary. The pain wasassessed with the Western Ontario and McMaster Universities Arthritis Index (WOMAC), the QOL wasassessed with SF-8, obesity was assessed with body mass index (BMI), and radiological evaluation of OA
progression using fully automatic program. Subjects in both groups were evaluated after 6, 12 and 24
months.
【Results】Concerning adherence to home exercise, the numbers of exercise times in a week in thevideo-based exercise group were 5.1±2.0, 4.0±2.3 and 3.6±2.4 times at 6-, 12- and 24-month, respectively.
The frequency of the exercise was significantly higher than those in the control group at 6-month follow-up.
The improvements in pain, stiffness and physical function categories of WOMAC were significantlygreater in the video-based exercise group than in the control group at all time periods. Physical component
summary score of SF-8 was greater at 6- and 12-month in the video-based exercise group than control
group, while there was no significant difference at 24-month. Concerning BMI, there was no significant
difference in the reduction between the video-based exercise and control groups. Regarding radiographic
OA progression, video-based exercise group showed significant increase in FTA at 12- and 24-monthcompared with the baseline, while we could not find significant progression in other parameters.
【Discussion】The present study was conducted to test the hypothesis that video-based home exercise could
enhance adherence to prescribed exercise program, produce substantial improvements in pain, physicalfunction and QOL in patients with knee OA, and also prevent radiographic progression of knee OA
compared with conventional home exercise without video media. The numbers of home exercises in a week
in the video-based exercise group were significantly greater than those in the control group at 6-monthfollow-up period. Concerning pain and physical function, the present study showed improvements in
WOMAC scores from the baseline were significantly greater in the video-based exercise group than in thecontrol group until 24-month follow-up. In addition, the improvement of SF-8 physical component
summary score from the baseline was significantly greater in the video-based exercise group than in thecontrol group at 6-month and 12-month follow-up. However, we also found that video-based home exercise
did not enhance adherence to prescribed exercise program after 12-month compared with home exercise
without video media or prevent radiographic progression of FTA of the knee for 24-month. Therefore, thefindings of the present study suggested that video-based home exercise can enhance adherence toprescribed exercise program and can produce substantial improvements in pain, physical function and QOL
in patients with knee OA, although our video-based home exercise cannot prevent radiographic progressionof the knee OA. In the present study, our prescribed exercise took approximate 30 minutes and 7-8 minutes
in the video-based exercise and the control groups, respectively. Considering the time required for theprescribed exercise, DVD media can improve adherence to prescribed exercise for a long period. In thepresent study, radiographic progression on JSA, mJSW, osteophyte area, and FTA has been assessed using afully automatic program. Our method can provide an objective, accurate, simple and easy evaluation of theradiographic knee osteoarthritis severity. We detected a significant decrease of FTA in the video-basedgroup at two years, while we could not detect another parameter. Also, no statistical differences were foundin radiographic osteoarthritis progression between two groups. These findings suggest that our video-based
home exercise cannot prevent radiographic progression of the knee osteoarthritis. There are limitations in
the present study. First, we did not blind the subjects to the treatment allocation, and participants were
aware of whether they were part of the treatment or control group. Second, a number of participants refused
their allocation in the control group.
【Conclusion】 The present two-year comparative study showed that video-based home exercise canenhance adherence to prescribed exercise program for 6 months and can produce substantial improvementsin pain, physical function and QOL in patients with knee OA at two years, but not to prevent radiographic
progression of the knee OA.