Knee Osteoarthritis

So you have osteoarthritis of the Knee. What can you do about it?

Osteoarthritis (OA) is the most common joint disorder in the world. OA affects the majority of people
over the age of 65 and is recognized as one of the leading causes of disability in the elderly.

There are 2 major risk factors that have been found for OA of the Knee:

1. Age – prevalence of OA increases with age; 14% of adults aged 25 and older have OA, while 34% will have OA after the age of 65.
2. Obesity – The risk of getting knee OA is approximately double the risk of those who are of normal weight or underweight.

Other factors include:

Systemic factors: increasing the vulnerability of the joint

• Gender (female > male)
• Bone density
• Nutritional factors
• Genetic predisposition

Local Mechanical factors:

• Malalignment
• Muscle weakness
• Alterations of the structural integrity of the joint (eg. Meniscal damage, ACL tear, etc.)

The most common sites of Osteoarthritis include:

• Hand – 70%
• Spine – 60%
• Knee – 30%
• Hip – 10%

How to recognize the characteristic symptoms of Osteoarthritis

Not all of these symptoms may appear.

It is very important to lose weight through a combination of diet and exercise.

Increased BMI has been associated with an increased prevalence of knee, hip, and hand OA.

Weight loss of 5 kg is associated with a 50% reduction in chance of developing OA and also slows progression.Felson DT, Zhang Y. Arthritis Rheum. 1998.

Gudbergsen H, Boesen M, Lohmander LS, et al. Weight loss is effective for symptomatic
relief in obese subjects with knee osteoarthritis independently of joint damage severity
assessed by high-field MRI and radiography. Osteoarthritis Cartilage. 2012;20(6):495–
502.

This study showed the following effects of a 16-week weight-loss regime on symptomatic
relief in an elderly and obese group of patients:

An improvement of 14% on the knee injury and osteoarthritis outcome score (KOOS)
A 64% response rate on the OARSI/outcome measures in rheumatology (OMERACT)
criteria independent of structural damage at baseline, muscle strength, and alignment.

Exercise increases aerobic capacity, muscle strength, and endurance
(these also facilitate weight loss).

All persons capable of exercise should be encouraged to participate in a
low-impact aerobic exercise program (walking, biking, swimming, aquatic
exercise, Tai chi).

Quadriceps strengthening exercises have been shown to lead to
improvements in pain and function:

Messier SP, Loeser RF, Miller GD, et al. Exercise and dietary weight loss in overweight
and obese older adults with knee osteoarthritis: the Arthritis, Diet, and Activity Promotion
Trial. Arthritis Rheum. 2004;50(5):1501-1510.

Ettinger WH Jr, Burns R, Messier SP, et al. A randomized trial comparing aerobic
exercise and resistance exercise with a health education program in older adults with
knee osteoarthritis. The Fitness Arthritis and Seniors Trial (FAST). JAMA.
1997;277(1):25-31.

Messier SP, Mihalko SL, Beavers DP, et al. Strength Training for Arthritis Trial (START):
design and rationale. BMC Musculoskelet Disord. 2013;14(1):208.

Adherence to exercise and physical activity is vital for long-term benefits.

Jordan JL, Holden MA, Mason EE, Foster NE. Interventions to improve adherence to
exercise for chronic pain in adults. Cochrane Database Syst Rev. 2010;1: CD005956
stimulation

Knee braces

Randomized trials of the effectiveness of braces for the treatment of medial knee OA demonstrate
that wearing an unloader knee brace gives a clinically significant and immediate improvement in the pain and function, approximately 50%, of patients with medial osteoarthritis of the knee, which is much
more than seen with typical NSAIDs prescription. Kirkley A, et al. J Bone Joint Surg Am. 1999.