What is osteoarthritis of the knee?
Osteoarthritis of the knee happens when the cartilage in your knee joint breaks down, enabling the bones to rub together. The friction makes your knees hurt, become stiff and sometimes swell. While osteoarthritis in the knee can’t be cured, there are many treatments to slow its progress and ease your symptoms. Surgery is an option for more severe forms of osteoarthritis.
How common is osteoarthritis of the knee?
Osteoarthritis of the knee is very common. Approximately 46% of people will develop it during their lifetimes.
Who is affected by osteoarthritis of the knee?
Women are more likely than men to develop osteoarthritis of the knee. Most people develop this condition after age 40. But other factors such as injury or genetics can cause it to happen earlier.
How does osteoarthritis in the knee affect my body?
Knee pain is the most common symptom of osteoarthritis in the knee, making it painful for you to jog, run, climb stairs or kneel. It can also make your knees feel stiff or swollen. Over time, osteoarthritis of the knee can change the shape of your knee joint, making your joint feel unstable or wobbly.
SYMPTOMS AND CAUSES
What causes osteoarthritis of the knee?
Osteoarthritis of the knee happens when your knee joint cartilage wears out or is damaged. Articular cartilage is tough, rubbery tissue on the ends of your bones that lets you bend and move. Meniscal cartilage absorbs shock from pressure on your knee.
Your cartilage is like your car’s shock absorber, protecting your car from bumps and jolts. Drive on lots of rough roads, your shocks wear out fast. Drive on easy streets, your shocks last longer. You can wear out or damage your knee joint cartilage if:
- You’re overweight. If your body mass index (BMI) is 30 or more, you’re seven times more likely to develop osteoarthritis in your knee than someone with a lower BMI.
- You injure your knee or have an old knee injury.
- You frequently put stress on your knee at your job or playing sports.
- You inherited a tendency to develop osteoarthritis of the knee.
- You have crooked bones or joints, such as having knocked knees.
What are the symptoms of osteoarthritis in the knee?
Pain is the most common symptom of osteoarthritis in the knee. Your knee might hurt when you move it, or even when you are just sitting still. Other symptoms are:
- Your knee feels stiff, particularly when you first get up or when you’ve been sitting for a long time.
- Your knee looks swollen or feels puffy.
- You hear a cracking or grinding noise when you move your knee.
- Your knee feels wobbly, as if it could buckle or “give out.”
- Your knee might lock up, or feel as if it is stuck.
DIAGNOSIS AND TESTS
How is osteoarthritis of the knee diagnosed?
Your healthcare provider will do a physical examination and ask about your medical history. The physical examination might include checks to see:
- If your knee joint area is red or sore.
- If there’s a sign you injured your knee.
- How much you can move your knee. This is called your range of motion.
- If your knee feels “loose,” which can mean your joint isn’t stable.
- The way you walk, in case you have gait problems that affect your knee. A gait problem is when you don’t walk as you would normally.
What tests do healthcare providers use to diagnose this condition?
- X-ray.
- Magnetic resonance imagery (MRI).
- Blood tests.
- Joint aspiration (arthrocentesis).
MANAGEMENT AND TREATMENT
How do you treat osteoarthritis of the knee?
Treatment might include nonsurgical treatments, injections and surgery. Typically, healthcare providers try non-surgical treatments before recommending surgery.
Non-surgical treatments include:
- Using pain medications.
- Doing physical therapy.
- Maintaining a healthy weight.
- Using a knee brace.
- Using orthotics such as insoles or special footwear.
- Cortisone (steroid) injections.
- Viscosupplementation.
Surgical treatments include:
- Cartilage grafting. Healthy cartilage is used to fill a hole in your cartilage.
- Knee osteotomy.
- Partial knee replacement.
- Total knee replacement.
What factors do healthcare providers consider when recommending surgery?
Your provider might recommend surgery if:
- Your symptoms aren’t better after non-surgical treatments such as medication and physical therapy.
- Your symptoms affect your quality of life.
- Tests show your knee joint is beginning to disintegrate.
PREVENTION
How can I prevent osteoarthritis of the knee?
While you can’t always prevent osteoarthritis of the knee, there are steps you can take to reduce the risk you’ll develop it:
- Maintain a healthy weight.
- Get plenty of rest.
- If you jog or run, do so on grass or soft surfaces.
- Vary your fitness routine with low-impact exercises such as swimming or cycling.
- Add light strength training to your fitness routine.
OUTLOOK / PROGNOSIS
What can I expect if I have osteoarthritis of the knee?
Unfortunately, the effects of osteoarthritis of the knee can’t be reversed. But treatment and self-care can help relieve your symptoms and slow your condition’s progress.
Will I always need medical treatment for osteoarthritis of the knee?
You might always need pain medication to ease your symptoms. Many people find exercise and physical therapy helps their symptoms. People also benefit from self-management programs that provide information about living with osteoarthritis of the knee. Talk to your healthcare provider about ways you can use exercise and other self-care to manage your symptoms.
LIVING WITH
How do I take care of myself with knee osteoarthritis?
It can be frustrating to cope with osteoarthritis of the knee symptoms that keep you from working or enjoying daily activities. Fortunately, there are several things you can do for your symptoms:
- Applying ice or heat reduces your knee pain, stiffness and swelling.
- Losing weight or maintaining a healthy weight takes stress off your knees.
- Enjoying activities such as swimming, biking or walking keeps your knee joint flexible.
- Using a knee brace or adding shock-absorbing inserts in your shoes can reduce pressure on your knees.
- Participating in self-management programs can help you feel more in control of your health.
When should I see my healthcare provider?
You should contact your provider if your knee hurts for no reason, or you have knee pain that’s getting worse.
When should I seek immediate medical attention?
You should go to the emergency room or contact your healthcare provider if your knee hurts and feels warm to the touch or your skin looks red. These are signs you might have an infection.
What questions should I ask my healthcare provider?
- Why does my knee hurt?
- Will I always be in pain?
- Will my other symptoms get worse?
- Will I need surgery?
- I have to be on my feet at my job. Will I be able to keep working?
- Will I be able to jog or run after treatment?
FREQUENTLY ASKED QUESTIONS
Can osteoarthritis of the knee cause pain in my hip, leg or calf?
Osteoarthritis of the knee can weaken your calf, thigh and hip muscles, but there’s no indication this muscle weakness is painful.
Does osteoarthritis of the knee cause bone pain?
Osteoarthritis of the knee causes your leg bones to rub together, which can lead to painful bone spurs.