Treatment for osteoarthritis (OA) of the knee is controversial. Only a few studies have compared the effects of intraarticular injection of hyaluronate with those of home exercise for knee OA. We prospectively evaluated the therapeutic effects of each treatment.
A total of 102 female subjects (mean age 70.4 years) were randomly divided into two groups and followed up to the 24th week. The primary outcome measure was judged by three pain/function scales as follows: a visual analogue scale, the Japanese Knee Osteoarthritis Measure, and the Outcome Measures in Rheumatology Clinical Trials and Osteoarthritis Research Society International criteria. For secondary outcome measures, all data were categorized for logistic regression analysis and the chi-squared test to address factors affecting these outcomes.
The two treatment groups demonstrated equal improvement regarding all three scales, and there was statistically no difference in between-group analyses, although there seemed to be better improvement in range of motion at 24 weeks in the home exercise group. In categorical analysis, OA stage was classified as early and advanced OA at 3 mm of joint space width obtained from standing anteroposterior radiographs. Logistic regression analysis revealed that the OA stage at the baseline of the knee affected these improvements. For early OA the improvement rate regarding hydrops was significantly higher in the home exercise group, whereas for advanced OA there was a tendency for the rate of improvement in ROM to be inferior in the hyaluronidate group.
Taking into account the cost, convenience, and invasiveness to patients, exercise is thought to have some advantage over intraarticular injection of hyaluronate for the therapy of OA of the knee.