Osteoarthritis is inflammation and pain that occurs when the protective cartilage in a joint is damaged or worn away. It can occur on just one side (left knee osteoarthritis or right knee osteoarthritis) or on both sides (bilateral knee osteoarthritis).
The ends of your bones have a layer of smooth, rubbery tissue called cartilage that protects them as they move. This protective layer is slippery and reduces friction where bones meet, allowing your joints to move easily. When the cartilage gets damaged—either from injury or from wear and tear with age—it can start to wear away, causing the bones to rub together directly. This bone-on-bone contact causes knee pain and inflammation.
Knee osteoarthritis is a degenerative knee condition that gets worse over time. There's no cure, but treatment for knee osteoarthritis can help manage the condition.
The most prominent symptoms of knee osteoarthritis are:
Doctors divide knee osteoarthritis into four stages to help patients better track and manage the progression of their condition over time:
The symptoms of knee osteoarthritis are caused by the deterioration of cartilage and the bones rubbing together, but what causes the cartilage to deteriorate?
Some people can damage their cartilage in accidents like sports injuries, but most osteoarthritis results from wear and tear. Your cartilage is like a shock absorber. Over time, it can wear out, either because of overuse or because your body becomes less effective at repairing and replacing it.
Risk factors for knee osteoarthritis include:
For most people, bone-on-bone knee pain is a dull ache that worsens over time. Some people experience sharp pain, but it's less common. Sometimes, the sensation is described as being similar to a toothache but in the knee. The pain may get worse with activity, especially high-impact exercise like running. It may be accompanied by a rough grinding sensation when you move your knee.
The most common cause of osteoarthritis in the knee is wear and tear from aging.
You can't reverse knee osteoarthritis or undo the joint damage it causes. Still, you can manage your symptoms and slow the progression of the condition through knee osteoarthritis treatments and sensible lifestyle choices.
Your doctor may recommend knee replacement surgery once your condition progresses and pain from knee osteoarthritis has a higher impact on your daily life.
The cartilage in your knee thins due to wear and tear from aging. As you age, it gets progressively thinner until there is not enough cartilage to support healthy joint movement. When that happens, you start to experience progressive pain, stiffness, and inflammation.
Exercising to strengthen the leg muscles can help give your knee more support. Low-impact exercises like walking can help you feel less stiff and painful and may slow the progression of your symptoms.
Maintaining a healthy lifestyle is the best way to slow the progression of knee osteoarthritis. Regular, low-impact exercise is your best defense against the disease. Eating a nutritious diet, maintaining a healthy weight, and managing related conditions like rheumatoid arthritis and diabetes can also help.
Arthritis can benefit from anti-inflammatory compounds and anti-oxidants, so unsweetened green tea, fruit juice, and coffee in moderation are good choices. It's also crucial to stay hydrated, so drink plenty of water throughout the day.
People with knee osteoarthritis should avoid high-impact activities like running and contact sports. Repetitive motions that work the knee are also a problem. However, you should also avoid being too sedentary, as inactivity can worsen your symptoms. Find a balance between staying active and overworking your knees.
It can be. It's normal to experience occasional noises when you move your joints. However, if the noise is persistent—or accompanied by a grinding feeling—it can be a sign of knee osteoarthritis or other knee conditions like a torn meniscus.
To schedule an appointment with one of our bone and joint specialists, call 617-732-5322, or fill out an appointment request form.
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