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Knee Pain

Is this your symptom?

  • Pain in the knee
  • Includes minor muscle strain from overuse
  • If pain is caused by an injury, see Knee Injury care guide

Causes of Knee Pain

  • Muscle Overuse(strained muscles). Knee pains are often from hard muscle work or sports. Examples are too much walking or running. This type of pain can last from hours up to 7 days.
  • Muscle Cramps. Brief pains that last 1 to 15 minutes are often due to muscle cramps. These often occur in the calf or feet at night. They can also occur in the hamstrings at the back of the knee and thigh.
  • Trapped Nerves. The nerves in the lower leg can become trapped or squeezed where they pass through narrow spaces as they leave the spine. Sciatica is from pressure on a nerve in the back. It causes tingling, weakness or pain in the leg which may go right down to the toes. You may feel pain from a trapped nerve in your knee. If symptoms do not go away with rest or treatment, surgery may be needed to release the nerve.
  • Viral Illness. Mild muscle aches in both legs or in the joints also occur with many viral illnesses, such as flu.
  • Septic Arthritis (serious). This is a bacterial infection of a joint space. Main symptoms are fever and severe pain when you move the joint. It may not be possible to move the joint at all. This needs care right away.
  • Joint Inflammation. Examples are rheumatoid arthritis, osteoarthritis and gout. Some, like gout, may affect just one joint. Others affect multiple joints at the same time. Early treatment may help prevent long-term damage to the joints involved.
  • Bursitis. Many joints, like the knee, are covered by fluid-filled sacs called bursae. They help the joint move smoothly. These bursae can get inflamed or infected, causing pain and swelling. The bursa at the front of the knee, over the knee-cap, can become inflamed from too much kneeling and knee bending. The area may look red and feel warm to touch.
  • Referred pain. Pain is sometimes felt in the knee when there is not actually a problem with the knee itself. This is called referred pain. Problems like arthritis in the hip can lead to pain being felt in the knee.
  • More serious causes of knee pain:
    • Bone cancer or bone infection (osteomyelitis). Fractures can happen during normal activity without an injury. Do not ignore ongoing leg pain.
    • Clots in the veins of the leg can cause pain and itching if they occur in veins near the surface of the skin. If clots occur in the deeper, bigger veins in the legs, it can be life-threatening. Pain may be felt behind the knee. Pieces of the clot can break off and travel to the heart and lungs. If this happens, it can cause breathlessness or chest pain.
    • Blockage of an artery. Arteries carry oxygen from your heart to the leg tissues. Symptoms of blockage are cold, pale and numb and/or painful leg. The blockage will need to be cleared as an emergency when this happens. Partial blockage can cause pain, often in the calf or behind the knee, when walking. The pain will usually go away when at rest but may need treatment before the artery becomes completely blocked.

Pain Scale

  • Mild: you feel some pain, but it does not keep you from any normal activities. Work, chores and sleep are not changed.
  • Moderate: the pain keeps you from doing some normal activities. It may wake you up from sleep.
  • Severe: the pain is very bad. It keeps you from doing all normal activities.

When to Call for Knee Pain

When to Call for Knee Pain

Call Doctor or Seek Care Now

  • Pain at the back of the knee and you are being treated for cancer or have recently been in hospital
  • Severe pain
  • Fever is present
  • Bright red area on skin with lines tracking out from the area
  • You feel weak or very sick
  • You think you need to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

  • Pain at the back of the knee and you have any of the following:
    • history of blood clots
    • history of cancer
  • You have pain at the back of the knee any of the following:
    • you are pregnant
    • gave birth in the past 6 weeks or
    • take hormone replacement therapy (HRT)
  • Pain get worse over several days
  • You think you need to be seen, but the problem is not urgent

Contact Doctor During Office Hours

  • Can't walk normally (limping)
  • Knee gives way when walking
  • Knee pain lasts more than 7 days
  • Knee pain keeps you from work or other activities
  • Knee pain happens often
  • Swollen knee
  • Muscles are weak (loss of strength)
  • Knee often locks, gets stuck, or catches
  • You have other questions or concerns

Self Care at Home

  • Caused by overuse
  • Mild knee pain

Call Doctor or Seek Care Now

  • Pain at the back of the knee and you are being treated for cancer or have recently been in hospital
  • Severe pain
  • Fever is present
  • Bright red area on skin with lines tracking out from the area
  • You feel weak or very sick
  • You think you need to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

  • Pain at the back of the knee and you have any of the following:
    • history of blood clots
    • history of cancer
  • You have pain at the back of the knee any of the following:
    • you are pregnant
    • gave birth in the past 6 weeks or
    • take hormone replacement therapy (HRT)
  • Pain get worse over several days
  • You think you need to be seen, but the problem is not urgent

Contact Doctor During Office Hours

  • Can't walk normally (limping)
  • Knee gives way when walking
  • Knee pain lasts more than 7 days
  • Knee pain keeps you from work or other activities
  • Knee pain happens often
  • Swollen knee
  • Muscles are weak (loss of strength)
  • Knee often locks, gets stuck, or catches
  • You have other questions or concerns

Self Care at Home

  • Caused by overuse
  • Mild knee pain

Care Advice for Knee Pain

  1. What You Should Know About Mild Knee Pain:
    • Strained muscles, tendons and ligaments are common after using them too much during sports or other activities. They can also happen from a fall.
    • Examples are running or walking too much or doing leg weights at the gym. They could be strained from starting a new sport.
    • Weekend warriors who are out of shape get the most muscle pains.
    • Here is some care advice that should help.
  2. Pain Medicine:
    • To help with the pain, take an acetaminophen product (such as Tylenol).
    • Another choice is an ibuprofen product (such as Advil). Ibuprofen works well for this type of pain.
    • Use as needed, but do not take more than the maximum recommended dosage as stated on the package.
    • If you are not sure what to take, ask a pharmacist.
  3. Cold Pack for Pain:
    • For pain or swelling, use a cold pack. You can also use ice wrapped in a wet cloth.
    • Put it on the sore muscles for 20 minutes.
    • Repeat 4 times on the first day, then as needed.
    • Caution: avoid frostbite by wrapping the ice pack. Do not put ice directly onto the skin.
  4. Use Heat After 48 Hours:
    • If pain lasts more than 2 days, put heat on the sore muscle.
    • Use a heat pack, heating pad or warm wet washcloth.
    • Do this for 10 minutes, then as needed.
    • Reason: increase blood flow and improve healing.
    • Caution: avoid burns by wrapping the heat pack. Do not put it directly onto the skin.
  5. Rest the Leg:
    • Rest the painful area as much as possible for 48 hours. Keep the foot, toes and other joints moving gently if you can.
    • Keep the leg raised above the level of your heart, if you can, to help limit swelling. Lying down with your leg raised on pillows or a rolled blanket can help.
  6. What to Expect:
    • A strained muscle hurts for 2 or 3 days.
    • The pain often peaks on day 2.
    • After severe overuse, the pain may last a week or more.
  7. Call Your Doctor If:
    • Fever or swelling of the knee occurs
    • Pain lasts more than 7 days
    • Pain gets worse over several days
    • You get swelling and redness over the knee
    • You think you need to be seen

And remember, contact your doctor if you develop any of the 'Call Your Doctor' symptoms.

Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.

Copyright 2023 Schmitt Decision Logic LLC.

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