Knee osteoarthritis (KOA) is a painful, chronic disease that affects the whole knee. In particular, KOA causes the cartilage, which cushions the area between the bones in the knee joint, to wear away. The loss of cartilage doesn’t happen overnight, but as it gets worse, the knee becomes more and more painful.
KOA is caused by two types of factors. “Inherent risk factors” are those that aren’t affected by external conditions. These include aging, genetics and hormonal changes. “Individual risk factors” are things that depend on personal differences. These include diet, obesity, injury, inflammation, metabolic disease, etc. Any given patient can have several different risk factors that contribute to their illness. These factors tend to interact in a negative way, making the condition even worse. For example:
As the condition of the knee gets worse, patients experience more pain.
The more it hurts, the less they move.
The less they move, the weaker their muscles become and, frequently, the more weight they gain.
As their muscles get weaker and they gain weight, moving puts more pressure on the joint.
As pressure on the joint gets worse, the pain gets worse.
And back to the beginning…..
This isn’t the only cycle of interactions. Some involve biochemical rather than mechanical issues. Others are psychological, such as the connection between depression and the increased sensation of pain. Together all these factors cause KOA to get worse as time passes. As this occurs, the entire joint continues to deteriorate.
Treatments for KOA
Eventually many patients with KOA are only left with one treatment option: total joint replacement. While this procedure can be of tremendous help, it is not something to be taken lightly. In between the start of KOA and total joint replacement, other treatment options are available. These include medications, physical therapy and injections. Injections include steroids as well as injections of replacement fluids (namely hyaluronic acid) into the synovial sac that helps cushion the knee joint.
Treating KOA Naturally
While many patients ultimately choose medical interventions over lifestyle changes, there are natural options for treating or preventing KOA. These options won’t replace medical treatment for most patients, but they can make a big difference. These include:
Weight loss. This helps relieve the load on the joint.
Balance training. This helps prevents falls, which may injure the joint as uncontrolled movement places excessive loads on it. An example would be falling and trying to catch yourself with a knee that is twisted out to the side.
Good nutrition. This gives the body the raw materials to create healthy tissue everywhere, including at the knee joint.
Moderate Exercise and KOA
When research first began, the role of exercise in KOA was the source of some confusion. Early studies looked at the effect of exercise on the knees of competitive athletes. These studies showed that exercise made KOA worse. This was true but misleading. Most people aren’t competitive athletes. When researchers began to look at the benefits of moderate exercise, they found something quite different. They discovered that moderate exercise actually helps prevent or at least slow the progression of KOA. Effects of exercise on knee osteoarthritis: A systematic review – PubMed (nih.gov)
Moderate exercise has many positive benefits for KOA:
By strengthening the muscles exercise helps take some of the load off of the joint in general.
By increasing our awareness of the position of our body at any given time, as well as strengthening muscles, exercise decreases the risk of falls. A fall can cause a person to twist the joint, putting weight on it from an uncontrolled angle, so that the load on the joint is briefly but dramatically, increased. Injury to the joint can contribute to KOA.
It helps decrease inflammation in the joint. Inflammation contributes to KOA.
It helps patients lose weight, which also helps decrease the load on the joint.
It helps prevent metabolic syndrome, which makes KOA worse.
Which Exercises Help? Which Exercises Hurt?
There is no “one and only” type of exercise for KOA because different types of exercise change the body in different ways. Here are a few examples:
Over time, KOA limits the range of motion of the knee. Stretching exercises help patients preserve their range of motion.
Exercises to improve balance (balance training) help prevent falls and the injuries that follow. Exercises that help us maintain our awareness of self-movement, body position and force (proprioception exercises), do the same thing. Surprisingly enough, walking backwards is a proprioception exercise.
Strength training exercises help build up the muscles around the knee joint, thus helping to reduce the load on the joint.
Aerobic exercises help improve cardiovascular function, which helps prevent or improve metabolic syndrome, a chronic disease that makes KOA worse. Aerobic exercise also helps lubricate the joint and keep it mobile.
When exercising for KOA, some types of exercises should be avoided.
Don’t engage in exercises that involve twisting the knees or coming to an abrupt stop. This would include basketball, volleyball and skiing.
Don’t engage in exercises that put an undue load on the joint. This includes lunges, deep squats and jumping.
Don’t try to be a competitive athlete. Too much exercise can be worse than too little.