Osteoarthritis (OA) is a major public health issue causing chronic pain, reductions in physical function and diminished quality of life. Ageing of the population and increased global prevalence of obesity are anticipated to dramatically increase the incidence of osteoarthritis and its associated impairments. In New Zealand alone, osteoarthritis affects 1 in every six people over the age of 15.
Exercise therapy is among the dominant non-pharmacological interventions recommended in the management of osteoarthritis with exercise being shown to incite functional adaption to mechanical loading, causing positive effects on cartilage, periarticular bone, muscle and joint mobility/range of motion. Conversely, physical inactivity (which is widely reported in those with osteoarthritis) has been associated with tissue atrophy, impairment in physical function and pain.
Osteoarthritis is thought to result from excessive mechanical stress applied in the context of systemic susceptibility. A number of factors including family history, age, ethnicity, diet and gender (females are at higher risk of developing osteoarthritis than males) all influence an individual’s susceptibility to developing osteoarthritis. Additionally, obesity and previous joint injuries (either acutely as in a sporting injury or after repetitive overuse such as occupational exposure) can also affect joint loading and thus development and/or progression of osteoarthritis. Exercise has been shown to be beneficial for both management and prevention of deterioration and co-morbidities. This is largely because physical activity leads to the modification of several risk factors. For example, from a public health perspective, body weight is the largest modifiable risk factor for osteoarthritis. Research has shown that for women of normal height, for every 11 lbs (5kg) of weight loss (approximately 2 BMI units), the risk of knee osteoarthritis decreased by >50%. Participation in regular structured physical activity can assist in the modification of body weight, which is an important consideration in exercise prescription for osteoarthritis.
Assessment and exercise prescription needs to be individualised and tailored to each patient and will differ depending on the site and severity of the individual’s osteoarthritis, as well as any other co-morbidities they may have. Research has shown that quadriceps muscle weakness is common among patients with knee osteoarthritis, the belief being that a manifestation of disuse atrophy develops because of unloading of the painful extremity. Quadriceps weakness was hence considered a risk factor for the development of knee osteoarthritis, presumably by decreasing the stability of the knee joint and reducing the shock-attenuating capacity of the muscle. Resistance training has been shown to reduce pain and disability in individuals with osteoarthritis and should, therefore, be included in exercise prescription as appropriate. Applying this concept clinically, a patient with knee OA would likely undergo assessment and exercise prescription for a knee-strengthening program as part of their exercise rehabilitation. Higher levels of muscular strength are also associated with a significantly better cardio-metabolic risk factor profile, lower risk of all-cause mortality, fewer CVD events, lower risk of developing physical function limitations, and lower risk for non-fatal disease. Aerobic exercise is also a vital component of exercise prescription in this population, as improvements in cardiorespiratory fitness (CRF) have been shown to elicit weight loss, improvement in pain and physical function as well as self-efficacy.
Additionally, improvements in risk profiles and overall mortality are also evident, with every 1-MET increment in CRF associated with a 13-15% risk reduction from all-cause mortality and CVD events. A comprehensive approach to exercise prescription is therefore vital for those with OA.
In order to achieve this within The Axis Arthritis Clinic, we first assess a patient’s aerobic fitness and muscular strength and endurance. Additionally, functional testing such as joint ROM and functional movement screening is performed in order to identify deficits in physical function and inform exercise prescription. From there, an individualised exercise program is formed, taking into consideration a whole host of factors that may need to be addressed, e.g. weight loss, poor CRF, strength deficits, reduced range of motion etc.
The patient is then supervised through a 12-week program in order to make sure that all exercises are being performed not only correctly (to ensure safety and that maximal benefit is being achieved), but also progressed as necessary so that the patient can achieve improvements in physical function and management of pain as quickly as possible. At the end of their program, a patient is reassessed in order to evaluate improvements in physical function and to form a new plan going forward so that they can ensure they feel confident and prepared to maintain the positive lifestyle changes they have implemented so far.
Exercise rehabilitation is of great benefit to those with OA, and should be implemented by a trained professional (such as a Clinical Exercise Physiologist) as part of a treatment plan in this population. It is vital that all patients received individualized assessment and prescription in order for them to achieve maximal health benefits from regular participation in physical activity in both a safe and effective way.
Are you or one of your patients suffering from osteoarthritis? Is the pain, swelling, stiffness, or potentially worse, symptoms significantly impacting your ability to undertake physical activity? Our specialist Arthritis Clinic could provide you with improvements you’ve been searching for.
Our clinic brings together a range of medical and allied health specialists to provide a comprehensive treatment plan, looking to optimise the non-surgical management (including exercise and diet) of osteoarthritis.
If this sounds like something you or your patient could benefit from, make an appointment to come in and see us.
To make an appointment call 09 521 9846