OSTEOARTHRITIS (OA) is the most common joint disorder, often affecting the knees and hips.1 Symptoms include pain, temporary stiffness, crepitus, swelling, fatigue, and movement limitation. OA is rarely present before the age of 40.1 Incidence is greater among men before the age of 45 but higher among women after the age of 55. After the age of 70, there is a dramatic increase in prevalence of OA among both sexes, and the majority of older adults will develop OA in 1 or several joints.2 Currently, more than 50% of Americans aged over 65 (over 24 million individuals) are affected by OA.3 With the aging population, some researchers predict that by 2030, approximately 72 million Americans will have developed the disorder.4, 5
In general, people diagnosed with OA will gradually become sedentary,6 because most of them are approximately 3 times more likely to have difficulty walking, and to have 5 or more functional limitations.2 The belief that physical activity causes an increase in pain to the affected joint has resulted in a negative chain reaction. Inactivity leads to decreased endurance and mobility, loss of independence, and thus it can reduce quality of life (QOL).7 In addition, OA is responsible for a reduction in productivity, and an increase in disability compensation and work absenteeism. These indirect costs represent one third of the overall costs attributed to OA, where the total cost is estimated at $16,146. Direct costs are disbursed for pain medication and general medical treatments. Together, individuals affected by OA present an annual average cost of $11,542.8
The Ottawa Panel is a group of researchers producing Evidence-Based Clinical Practice Guidelines (EBCPGs) with the objective of reporting recommendations regarding specific interventions. General aerobic exercise is recommended as a core treatment for subjects with OA. An aerobic walking program is defined as “a dynamic physical activity with an intensity sufficient to improve aerobic capacity, and muscle strength, which establishes to improve functional status among older individuals with OA.”9(p677) Many previous systematic reviews have already determined that walking is an effective and safe way to treat OA, but these reviews are now dated.10, 11 The scientific evidence recommends that aerobic physical activities, such as walking programs, have a therapeutic effect in the short-term (2–6mo) for pain relief, improved strength, and functional status in subjects diagnosed with OA.12, 13, 14 However, these existing guidelines do not provide detailed recommendations regarding effective walking programs for OA. Therefore, an update of clinical practice guidelines for aerobic walking programs for OA would be a valuable resource for clinicians and researchers.8, 10, 11
The objective of this project was to create an EBCPG for an aerobic walking program in the management of OA of the knee, in order to support health professionals and their patients diagnosed with OA in choosing the most effective aerobic walking programs for this population. Evidence shows that an inactive patient with OA will present a gradual deterioration of the affected joint, an increase of functional dependency, and a poorer QOL.7 It is, therefore, important to persuade inactive individuals to follow an aerobic walking program, which helps relieve pain and promote remodeling without increasing stress in the affected joint.15 Even though aerobic walking promotes low impact on the weight-bearing articulations, positive changes are still attributed to improving joint loads and biomechanics, stability, and neuromuscular function.15 Therefore, the stability of the affected joint assists persons with OA to be more functional in everyday living, which will progressively improve their QOL.16 Promotion of aerobic walking, especially in a community-based context, is a priority for health organizations serving the general population and is highly recommended for subjects affected by OA, because it is easily accessible to walk in a shopping center or a community place, without having to spend too much money. In other words, walking is one of the safest no-cost ways of doing physical activity, because no special equipment is needed other than good walking shoes.6
The Ottawa Panel found important evidence to support the use of aerobic walking programs in the management of OA, for subjects aged over 40 years who are diagnosed with mild to moderate OA of 1 or both knees. Evidence from 7 high-quality studies demonstrates that facility, hospital, and home-based aerobic walking programs with other therapies are effective interventions in the shorter term for the management of patients with OA to improve stiffness, strength, mobility, and endurance. Moreover, the greatest improvements were found in pain, QOL, and functional status. In summary, it would be strongly recommended to use the Cochrane Risk of Bias Summary assessment to evaluate the methodologic quality of the studies. Moreover, it would be interesting to consider other avenues for future research on how aerobic walking programs would be beneficial in the management of OA of the hip, because OA most often affects the weight-bearing articulations, thus the knees and the hips. Moreover, 30% to 40% of individuals diagnosed with knee OA have concomitant hip OA.111 Also, in view of the fact that a number of individuals diagnosed with OA are overweight, another area for further work would be to perform a literature review by including studies that selected participants with a BMI greater than 25kg/m2 in walking programs. Finally, given the lack of long-term trials selected in this review, it would be interesting to examine further the long-term effects of the aerobic walking programs in the overall management of OA.
Archives of Physical Medicine and Rehabilitation
Volume 93, Issue 7 , Pages 1269-1285, July 2012