Knee pain is a common symptom in people of all ages. It may start suddenly, often after an injury or exercise. Knee pain also may begin as a mild discomfort, then slowly get worse.
Knee pain can have different causes. Being overweight puts you at greater risk for knee problems. Overusing your knee can trigger knee problems that cause pain. If you have a history of arthritis, it could also cause knee pain.
The location of knee pain can help identify the problem. Pain on the front of the knee can be due to bursitis, arthritis, or softening of the patella cartilage as in chrondromalacia patella. Pain on the sides of the knee is commonly related to injuries to the collateral ligaments, arthritis, or tears to the meniscuses. Pain in the back of the knee can be caused by arthritis or cysts, known as Baker's cysts. Baker's cysts are an accumulation of joint fluid (synovial fluid) that forms behind the knee. Overall knee pain can be due to bursitis, arthritis, tears in the ligaments, osteoarthritis of the joint, or infection. Instability, or giving way, is also another common knee problem. Instability is usually associated with damage or problems with the meniscuses, collateral ligaments, or patella tracking.
Here are some common causes of knee pain:
- Arthritis -- Including rheumatoid arthritis, osteoarthritis, lupus, and gout
Arthritis is inflammation or degeneration of one or more joints. A joint is the area where 2 bones meet. There are more than 100 different types of...Read Article Now Book Mark Article
Rheumatoid arthritis (RA) is a disease that leads to inflammation of the joints and surrounding tissues. It is a long-term disease. It can also aff...Read Article Now Book Mark Article
Osteoarthritis (OA) is the most common joint disorder. It is due to aging and wear and tear on a joint.Read Article Now Book Mark Article
Systemic lupus erythematosus (SLE) is an autoimmune disease. In this disease, the immune system of the body mistakenly attacks healthy tissue. It c...Read Article Now Book Mark Article
- Baker cyst -- A fluid-filled swelling behind the knee that may occur with swelling (inflammation) from other causes, such as arthritis.
- Cancers that either spread to your bones or begin in the bones
- Osgood-Schlatter disease
- Infection in the bones of the knee
- Infection in the knee joint
INJURIES AND OVERUSE
- Bursitis -- Inflammation from repeated pressure on the knee, such as kneeling for a long time, overuse, or injury
- Dislocation of the kneecap
- Fracture of the kneecap or other bones
- Iliotibial band syndrome -- Injury to the thick band that runs from your hip to the outside of your knee
- Patellofemoral syndrome -- Pain in the front of your knee around the kneecap
- Torn ligament. -- An anterior cruciate ligament (ACL) injury, or medial collateral ligament (MCL) injury may cause bleeding into your knee, swelling, or an unstable knee
Anterior cruciate ligament (ACL)
An anterior cruciate ligament injury is the over-stretching or tearing of the anterior cruciate ligament (ACL) in the knee. A tear may be partial or...Read Article Now Book Mark Article
- Torn cartilage (a meniscus tear) -- Pain felt on the inside or outside of the knee joint
- Strain or sprain -- Minor injuries to the ligaments caused by sudden or unnatural twisting
A strain is when a muscle is stretched too much and tears. It is also called a pulled muscle. A strain is a painful injury. It can be caused by an...Read Article Now Book Mark Article
Knee Pain Myths & Facts Quiz
Knee pain only happens to older people.Correct AnswerThe correct answer is myth. Knee pain can occur in people of all ages. It may start suddenly, after an injury or exercise. It also may begin as mild pain that slowly worsens over time.
Being overweight can put you at higher risk for knee problems.Correct AnswerThe correct answer is fact. Every extra pound you carry adds about five extra pounds of pressure on your knees when you go up and down stairs. If you need to shed a few pounds, talk with your doctor about healthy ways to lose weight.
If you have knee pain, it’s probably arthritis.Correct AnswerThe correct answer is myth. Arthritis is a common cause of knee pain, but there are many others. These include bursitis, tendinitis, sprains, and strains. If minor knee pain doesn’t go away after three days of home treatment, see your doctor.
Heat is the best treatment for any new knee pain.Correct AnswerThe correct answer is myth. When you have new knee pain, it’s best to apply ice. Cover your knee with a towel and place ice on it for 15 minutes at a time. At first, you can use it every hour for up to 15 minutes. After the first day, use it at least four times a day. Other treatments include resting your knee and keeping it raised.
Bursitis is often caused by overuse of your knee.Correct AnswerThe correct answer is fact. Bursitis is the swelling and irritation of the bursa. This is a fluid-filled sac that acts as a cushion between muscles, tendons, and joints. You can get bursitis from suddenly becoming more active or from being overweight. You may notice redness and swelling around the knee and stiffness or pain when you move your knee.
Standing can make knee pain from bursitis worse.Correct AnswerThe correct answer is true. To relieve the pain, try not to stand for long periods and place a pillow between your knees when sleeping on your side. You can use ice up to four times a day, 15 minutes at a time for the first two to three days to relieve pain.
Pain in the front of the knee is often caused by:Correct AnswerThe correct answer is all of the above. Stretching and strengthening the muscles in the front and the back of the leg help with this type of knee pain. Ask your doctor or physical therapist to show you exercises for your upper leg muscles.
If you have pain in the front of the knee, it may help to:Correct AnswerThe correct answer is all of the above. While exercise is good for your joints, certain high-impact activities can do more damage than good if you have joint pain. Taking steps to reduce the impact on your knees during exercise can help protect your joints.
Warming up and stretching before exercise helps protect your knees.Correct AnswerThe correct answer is fact. Warming up will help reduce the pressure on your knees during exercise. Start by walking for a few minutes. Then stretch the muscles in the front and back of your thighs to reduce tension in the knee. Ask your doctor or physical therapist for other suggestions for stretching.
If you hear a “popping” sound when you injure your knee, it’s most likely:Correct AnswerThe correct answer is E. If you have one of these knee injuries, you will often feel the symptoms right away. You may also have knee swelling, knee pain when walking, or locking or catching of the knee. If you have any of these symptoms, call your doctor right away.
Physical therapy is most helpful for which kind of knee pain?Correct AnswerThe correct answer is all of the above. Physical therapy can teach you exercises to make your knee stronger. A physical therapist may also use certain treatments to help relieve your knee pain. Ask your doctor if you should have physical therapy for your knee pain.
Simple causes of knee pain often clear up on their own while you take steps to manage your symptoms. If knee pain is caused by an accident or injury, you should contact your health care provider.
If your knee pain has just started and is not severe, you can:
- Rest and avoid activities that cause pain. Avoid putting weight on your knee.
- Apply ice. First, apply it every hour for up to 15 minutes. After the first day, apply it at least 4 times per day. Cover your knee with a towel before applying ice. DO NOT fall asleep while using ice. You can leave it on too long and get frostbite.
- Keep your knee raised as much as possible to bring down any swelling.
- Wear an elastic bandage or elastic sleeve, which you can buy at most pharmacies. This may reduce swelling and provide support.
- Take ibuprofen (Motrin) or naproxyn (Aleve) for pain and swelling. Acetaminophen (Tylenol) can help relieve pain, but not swelling. Talk to your provider before taking these medicines if you have medical problems, or if you have taken them for more than a day or two.
- Sleep with a pillow underneath or between your knees.
Follow these general tips to help relieve and prevent knee pain:
- Always warm up before exercising and cool down after exercising. Stretch the muscles in the front of your thigh (quadriceps) and in the back of your thigh (hamstrings).
- Avoid running down hills -- walk down instead.
- Bicycle, or better yet, swim instead of run.
- Reduce the amount of exercise you do.
- Run on a smooth, soft surface, such as a track, instead of on cement or pavement.
- Lose weight if you are overweight. Every pound (0.5 kilogram) that you are overweight puts about 5 extra pounds (2.25 kilograms) of pressure on your kneecap when you go up and down stairs. The amount of extra pressure is even greater when you jump. Ask your provider for help losing weight.
- If you have flat feet, try special shoe inserts and arch supports (orthotics).
- Make sure your running shoes are well made, fit well, and have good cushioning.
Further steps for you to take may depend on the cause of your knee pain.
When to Contact a Medical Professional
Call your provider if:
- You cannot bear weight on your knee.
- You have severe pain, even when not bearing weight.
- Your knee buckles, clicks, or locks.
- Your knee is deformed or misshapen.
- You cannot flex your knee or have trouble straightening it all the way out.
- You have a fever, redness or warmth around the knee, or a lot of swelling.
- You have pain, swelling, numbness, tingling, or bluish discoloration in the calf below the sore knee.
- You still have pain after 3 days of home treatment.
What to Expect at Your Office Visit
Your provider will perform a physical exam, and look at your knees, hips, legs, and other joints.
Your provider may do the following tests:
- X-ray of the knee
- MRI of the knee if a ligament or meniscus tear could be the cause
- CT scan of the knee
- Joint fluid culture (fluid taken from the knee and examined under a microscope)
Your provider may inject a steroid into your knee to reduce pain and inflammation.
You may need to learn stretching and strengthening exercises. You also may need to see a podiatrist to be fitted for orthotics.
In some cases, you may need surgery.
C. Benjamin Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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