Educational program promoting regular physical exercise improves functional capacity and daily living physical activity in subjects with knee osteoarthritis

The present investigation was a longitudinal prospective study conducted in a single center in Brazil that assessed 300 middle-aged and older patients with an established diagnosis of bilateral (294 patients) or unilateral knee OA for at least 1 year (Kellgren/Lawrence scale grades of I-IV) [11]. All volunteers were recruited from the Osteometabolic Disease Group, Institute of Orthopedics and Traumatology, School of Medicine, University of São Paulo, and they were under drug therapy (diacerein) for the 6 months prior to inclusion. To meet the eligibility criteria, patients needed to have met the American College of Rheumatology criteria for knee OA [12], to not have rheumatoid arthritis or any other rheumatologic disease other than OA, to be under routine care for knee OA for at least the previous 6 months, to not have any neurological problems, and to be able to understand and provide informed consent. Patients with uncontrolled cardiovascular or metabolic diseases, who underwent surgery or who had lower limb injuries during the previous 6 months were also not included. Baseline characteristics of the volunteers included in the present study are presented in Table 1.

Following screening for inclusion criteria, the volunteers have their functional capacity and physical activity levels assessed before, and after 6 and 12 months of follow-up. Volunteers were then randomly allocated into an educational program (EDU; n = 150) or control group (CON; n = 150) (Fig. 1). The EDU group participated in an educational program by a multidisciplinary group (orthopedic surgeons, physical education professionals, nutritionists, physiotherapists, occupational therapists, psychologists and social workers), which emphasized the recommendation for regular practice of home-based exercise in addition to the conventional clinical treatment. The CON group received only the conventional clinical treatment. The functional capacity and physical activity levels assessment were performed by members of the physical education team that were blinded for volunteers’ groups allocation.

The conventional treatment for knee OA included clinical follow-up by orthopedic surgeons; blood testing for metabolic syndrome (and referring for general practitioner clinical treatment as indicated), and calcium metabolism; X-rays, densitometry, and more specific image exams (e.g. ultrasound and magnetic resonance imaging) according to symptoms. Diacerhein was prescribed for all volunteers. A muscle relaxant and magnesium were prescribed for volunteers who reported cramps. All volunteers were oriented to take paracetamol and codeine when presenting moderate to severe knee pain. Low doses of nonsteroidal anti-inflamatory drugs were used only occasionally for severe pain, and during short periods of time. Vitamin D3 and calcium supplements were prescribed according to blood levels and bone densitometry results. Alendronate was prescribed for volunteers with osteoporosis. When necessary, orthotics (i.e. valgus or varus insoles, canes, walkers, and custom-made hand orthotics) were prescribed according to the disease severity, which was assessed by 3 orthopedic surgeons using the Kellgren and Lawrence classification, as previously described [10]. Volunteers with impaired mobility and pain were also referred to physical therapy and acupuncture.

All EDU and CON volunteers underwent functional capacity and physical activity levels assessment before and during 6 and 12 months of follow-up. Measures of functional capacity included the sit and reach, 6-min walking test (6MWT), timed up and down stairs test, timed up and go test (TUGT), and five times sit-to-stand test (FTSST), which were performed in a single day, following the sequence described below, and with a 3-min rest interval between them. The classic sit and reach test was used to assess the posterior thigh and lower back flexibility as previously described [13]. The 6MWT measured the distance covered while walking on a 15 m corridor without inclination. Volunteers were instructed to walk as fast as possible (without running) at a steady pace [14], and had their baseline (pre-test), peak (immediately after the end of the test) and recovery (2 min after the end of the test) heart rate measured with a digital frequency meter (Polar F1, Polar®, Finland). The timed up and down stairs test measured the time taken to ascend and descend a flight of 15 steps (15 cm high and 30 cm depth) as quickly as possible, starting from the standing position with their preferred leg, whereas it was allowed to use the handrail if necessary [15]. The FTSST measured the time taken to perform 5 repetitions of rising from a standard chair without armrest (seat height of 46 cm) to a full upright position as quickly as possible and without assistance [16]. The TUGT measured the time to get up from a chair without armrest (seat height of 46 cm) and without assistance, walk 3 m at normal speed, turn around, walking back and sitting down [17]. After the functional capacity assessment, the International Physical Activity Questionnaire (IPAQ) short version (validated in Brazilian population) was used to assess the daily physical activity level in all volunteers [18].

In addition to the conventional medical treatment, EDU group underwent an educational program with the health professional multidisciplinary team in order to make volunteers aware of their illness (OA) and their role on its treatment/management. The educational program occurred in a single day (Saturday, from 8 a.m. to 5 p.m.), and included 7 lectures of 30 min by each professional team, and 60-min workshops by the physical education, physical therapy and occupational therapy professionals, approaching the importance of their area in knee OA treatment/management.

The lectures occurred at morning. The orthopedic surgeon team introduced the anatomy of a joint and the pathophysiology of knee OA, its causes, irreversibility, and management. The physical education professionals lectured was about the health-related benefits of physical exercise and its role on knee OA management, the differences between physical activity and exercise, and the importance of improving physical fitness. The physical therapists also called attention for the role of performing physical exercise regularly, showed how to improve physical exercise to move from pain to a state of no pain, and talked about techniques to alleviate pain. The occupational therapists introduced the importance of protecting joints in daily activities by optimizing ergonomics and alternating different levels of energy expenditure. The nutritionist talked about the importance of a well-balanced diet (reduced quantity, colorful, whole grains, and low-calorie meals). The psychology team lectured about personality characteristics from childhood to adulthood, the difference between having a disease and being sick, the importance of their choices and not their conditions or feelings, and coping skills. The social work team showed where and how volunteers could and should include habits of regular leisure, sports and social gathering, and tasks. It is important to note that the role of changing habits was reinforced by each professional team, whereas the importance of practicing regular exercise was commented in all lectures.

The 3 workshops occurred at afternoon. The physical education workshop was about how to perform exercise (resistance and aerobic) at home, using low-cost alternative tools, as well as how to exercise at the appropriate exercise intensity. Volunteers were instructed to accumulate 30 to 60 min/day (bouts of at least 10 min) of moderate-intensity aerobic exercise (11 to 13 at the 6–20 rating of perceived (RPE) scale) [19], for 5 days a week. Alternatively to the moderate-intensity aerobic exercise recommendation, if physical capacity and disease severity allowed, volunteers were instructed to accumulate 20 to 30 min/day (bouts of at least 10 min) of vigorous-intensity aerobic exercise (14 to 16 at the 6–20 RPE scale) [19], for 3 days a week. Volunteers were instructed to perform the aerobic exercise modality they prefer (e.g.: walking, stationary cycling, dancing, swimming...). However, if weight bearing aerobic exercise was not tolerated (e.g.: there was a knee pain increase during or after exercise), they were instructed to perform stationary cycling or aquatic exercise. In addition to aerobic exercise recommendation, volunteers were instructed to perform 2 to 3 sets of 8 to 12 repetitions (1 to 2 min of interval between sets), in 10 resistance exercise (bench press, squat, seated row, knee extension, shoulder press, knee curl, triceps push-down, calf raise, biceps curl, and abdominal), for 3 times a week (nonconsecutive days). The volunteers were taught that they could perform the resistance exercises using weight-lifting machines, weight bearing, dumbbells, or some adapted material taught in the classes, (ankle weights, bars, elastic band, bottles with water or sand...), at an intensity between 14 and 17 at the 6–20 RPE scale) [19], using proper form and avoiding the Valsalva maneuver. The physical therapy team taught the volunteers how to adapt the exercise recommendation if they had knee pain and what they could do to alleviate knee pain at home, whereas the occupational therapy team taught how to protect the joints during both exercise and daily living activities.

The volunteers also received a printed material containing summaries of all lectures, and the exercises and practical recommendations of the 3 workshops, as well as a DVD with all the lectures and workshops. All volunteers were asked to watch the DVD and/or to read the booklet at least 3 times.

The Kolmogorov-Smirnov test was used to analyze data normality. Parametric variables were reported as mean ± standard error, whereas non-parametric variables (physical activity levels) were reported as percentage of prevalence. Two-way ANOVA with repeated measures (group vs. time) was used to indicate inter- and intra-interventions differences in data presenting Gaussian distribution, and the Bonferroni’s post hoc test was performed to identify significant differences indicated by ANOVA. The Chi-square test was used to analyze inter- and intra-interventions differences in physical activity levels. The statistical program SPSS™ 17.0 for Windows (SPSS Inc., Chicago, IL, EUA) was used to perform the statistical analysis.