Aquatic physiotherapy in the functional capacity of elderly with knee osteoarthritis

Introduction: Physicaltherapy in patients with osteoarthritis (OA) acts to decrease pain, increase joint functionality and to promote improvement in quality of life. Objective: To analyze the effect of a structured program of aquatic physiotherapy (AP) on functional capacity (FC) and mobility of elderly people with OA. Methods: Prospective, quantitative and analytical, randomized control study. The sample consisted of 29 patients, aged 60 years or over, diagnosed with OA, randomly allocated to the intervention group (IG), composed of 17 participants who underwent BP for two months, and to the control group (CG) of 12 participants. The primary outcome was measured by the WOMAC instruments and six-minute walk test. As a secondary endpoint, the Timed Up and Go Test measured mobility. Descriptive statistical analysis was used to present the data, with mean and standard deviation values. The comparison between groups for potential confounding factors and in relation to evolution was performed using the non-parametric chi-square test, Fisher's exact test and the Kruskal-Wallis test, and Dunn's test for multiple comparisons. The differences were considered statistically significant when p < 0.05. Results: There was a significant difference in physical and functional parameters related to pain (p < 0.001), stiffness (p < 0.001) physical activity (p < 0.001), distance covered in six minutes (p = 0.001), and mobility (p < 0.001) when comparing IG to CG. Conclusion: The structured AP program effectively contributed to the improvement of FC and mobility of elderly people with knee OA.


Introduction
The aging of the population occurs on a global scale. In Brazil, the number of elderly people was 16%, surpassing the mark of 34 million in 2019. 1 Longevity brings within chronic degenerative diseases that limits the functional capacity (FC) of affected population. Osteoarthritis (OA), a chronic degenerative disease of high prevalence, is a musculoskeletal disorder usually with insidious, progressive and slow pattern, which typically affects the joints such as hands, spine, hip and knees. 2 It is the most common joint disorder, affecting between 6% and 12 % of adult population and more than a third of those who are aged 65 years or more. 3 In addition to aging, obesity, trauma, joint surgery, hormonal imbalance, heredity, nutrition and bone density are some of the factors that predispose to OA. 2 Signs and symptoms related to OA in the population are related to: pain during the day, with relief when the individual is at rest; swelling and tenderness in the joints with or without the presence of crackles; morning stiffness and decreased range of motion, with decreased aerobic work capacity; and muscle weakness in the lower limbs. 4 In addition to pain and stiffness, knee OA can impact mobility in the elderly, resulting in significant impairment of functional capacity. 5 Physiotherapy´s main objectives in patients with OA are to decrease pain, increase joint functionality and consequently promote improvement on the patient quality of life. The physiotherapist has several nonpharmacological resources to achieve those goals, such as the use of kinesiotherapy, manual therapy and electro thermal therapy. 6 In this perspective, aquatic physiotherapy (AP) appears as a therapeutic resource widely used for the treatment of rheumatic diseases, as it facilitates the movements and reduces joint overload. 7,8 Various therapeutic effects are achieved with immersion in warm water, such as muscle relaxation, analgesia and reduction of joint impact. 9 Therefore, based on clinic and scientific evidence, the study was developed in order to verify the effects of a structured protocol of AP in the FC and mobility of elderly participants with knee OA.

Design overview
This study was a prospective, quantitative and analytical clinical trial of randomized control, which is interested in the prognostic factor of a therapeutic On the second day, the WOMAC questionnaire, the TUG and the functional classification based on the ACR criteria were applied. Evaluation after two months: the same procedures were repeated after the end of the treatment protocols in a maximum of seven days.

Interventions
The activities of the IG program (Table 1) were performed in the hydrotherapy sector of UniFAI, São Paulo, Brazil, that is equipped with cloakroom, lighting, and water equipment such as spaghetti, steps, ankle weights, triangular dumbbells, cervical and pelvic vests. The AP program was conducted over a period of two months, totaling sixteen sessions with approximately 60 minutes each. The activities were carried out by two examiners, one responsible for collecting the initial data and supporting the distribution of equipment and the other for directing the proposed treatment.
All participants were instructed to wear appropriate clothes for aquatic practice; they were also oriented on how to behave in an aquatic environment.
Participants from the CG did not receive any physiotherapy in two months. Weekly phone calls were done in order to follow them up.

Results
In total, 29 elderly with knee OA participated of the study. The IG consisted of 15 women and 2 men, and CG was composed of 10 women and 2 men. There was a sample loss in the CG of four participants, three of them by dropping out and one by having performed an infiltration in the knee.
Comparisons among socio demographic variables showed no significant differences between IG and CG groups (p < 0.05) regarding potential confounders ( Table 2). The same occurred with dependent variables (pain, stiffness and physical disability, related to physical and functional aspects, mobility and functional capacity), demonstrating a homogeneous distribution of the sample.
Comparing the variables after the intervention (pain, stiffness and physical disability, related to functional capacity aspects, and mobility), we observed that participants in the IG obtained statistically significant changes of all variables compared to the CG (Table 3).

Conclusion
Significant improvements in pain, stiffness, functional capacity, gait time and mobility were seen in participants from the AP programme when compared to elderly with knee OA who did not receive any physiotherapy treatment.