This study was a randomized controlled trial with a field-based assignment. The subjects were patients with KOA aged 50–85 years from two selected villages with similar socioeconomic statuses in a suburban community of Khon Kaen Province, Thailand. These two villages are small, and travel within them is difficult. Additionally, they were found to be in need of health promotion for people with KOA. A simple randomization was used to allocate each village into either the TPT or SPT program. The protocol and informed consent form were approved by the Khon Kaen University Ethics Committee for Human Research.
The diagnosis of KOA was confirmed for each patient based on their medical history report and a physical examination performed by physical therapists based on the clinical criteria of the American College of Rheumatology (1986)18). The inclusion criteria consisted of pain in the knee and three of the following conditions: 1) aged at least 50 years of age, 2) less than 30 min of morning stiffness, 3) crepitus on active motion, 4) bony tenderness, 5) bony enlargement, and 6) no palpable warmth of the synovium. The subjects who met the inclusion criteria were asked to join and had to sign an informed consent form before participation. All individuals were able to walk and were assessed for all measurements. Each of them received standard medical management of KOA from a local primary care unit.
The exclusion criteria consisted of diagnosis of KOA caused by other diseases, such as rheumatoid arthritis, or gouty arthritis or any accident/sports, contagious diseases, uncontrolled hypertension or diabetes mellitus, neurological deficits, or psychological symptoms. Subjects who were unable to perform standing and walking, or had received a knee replacement and those whose doctors advised against massage and exercise due to an underlying disease were also excluded. Twenty-four patients in the Thai physical therapy (TPT) group and 20 patients in standard physical therapy (SPT) group were assessed for their eligibility to participate in the study. Thirteen subjects were excluded for failing to meet the inclusion criteria. The remaining subjects, 17 in the TPT group and 14 in the SPT group, fulfilled the above criteria and agreed to participate in the study.
The TPT and SPT programs consisted of two phases. The first phase include class-based TPT and SPT group intervention programs at an appointed public indoor area in each village, and these programs were also associated with a home program. All subjects were asked to attend their group class, which was supervised by a researcher, three days/week. Additionally, they were recommended to follow their program at home at least two days/week for eight weeks. The second phase was performing the actual home self-care program with TPT or SPT alone, at least three times/week for twelve months. To extend the benefits of the home program, subjects received the booster session once a month during the first three months. Researchers incorporated content into each booster session to stimulate subject education and awareness regarding self-management, which included physical activity and exercise planning, and discussion of other related problems.
In the TPT group, exercise with a wand consisted of six exercises that were based on a past study13) that emphasized exercise in the muscle of the quadriceps and hamstrings. Concentric and eccentric isotonic contraction are applied with different positions (Fig. 1). These exercises are suitable for the knee joints and low impact. Each exercise was performed five times/session, two sets/day, and this was increased every two weeks until reaching 40 times/session. In the Thai massage session, the massage method used pressure on muscle lines of the quadriceps, hamstrings, tibialis anticus, and calves. To apply deep pressure, one or two thumb pads or the side of an elbow tip was used in some cases. Superficial heating with Thai herbs, containing 10 ingredients consisting of camphor, Kurkumin, lemon grass, and turmeric leaves, in a bag was applied to various areas of both upper and lower leg muscles and to cover the knees. In the SPT group, six progressive strengthening exercises for the quadriceps and hamstring muscles based on a past study were used19). Each exercise was performed 10 times/session, 2 sets/day, and the resistance was increased every two weeks (0.5 to 2 kg). The increase in load was flexible and depended on the subject’s requirements. Swedish massage consisted of superficial and deep stroking, and kneading or stroking various muscles of both the upper and lower leg. Additionally, a superficial heating bag filled with hot water was placed on the same areas. All subjects were suggested to perform the 30-minute exercise program, receive the 30-minute massage, and receive the 15-minute superficial heat/cold care whenever they might normally use an ice pack for acute or subacute knee pain. All outcomes were measured at baseline and at 2, 5, 8, and 14months. The primary outcome was the six-minute walk test (6MWT). The secondary outcomes included functional capacity evaluated by the Thai versions of the Western Ontario and McMaster Osteoarthritis Index (WOMAC) and quality of life (Thai Short Form-36, SF-36). The 6MWT was used for evaluating subjects’ walking capacity by measuring the distance walked during a defined period. The Thai 5-point Likert version of the WOMACTM 3.1 Index that was selected included 24 items grouped into 3 dimensions: pain (5 items), stiffness (2 items), and function (17 items). The SF-36 is a health-related quality of life (QOL) instruments that contains two dimensions, physical health (PH) and mental health (MH) (each range, 0–100). Adherence to the home program was assessed on a 5-point scale (1 time/wk = almost never, 2 times/wk = occasional adherence, 3 times/wk = regular adherence, 4 times/wk = often adherence, ≥ 5 times/wk = very often)20). All data are presented as means ± SD. Outcomes were analyzed using repeated measures analysis of variance (ANOVA) for evaluating differences within groups, and analysis of covariance (ANCOVA) was used for evaluating differences between groups. In the ANCOVA, the baseline values for all outcome variables in the posttest were adjusted for baseline differences. A p value < 0.05 was used as the criterion for statistical significance.