Knee pain is a common complaint that affects people of all ages.  There are many causes to knee pain, that is why it is important to make a correct diagnosis of the cause of knee pain so that the doctor can do the appropriate treatment.

Knee pain can be caused by a sudden injury, an overuse injury, or by an underlying condition, such as arthritis. Treatment will vary depending on the cause. Symptoms of knee injury can include pain, swelling, and stiffness.

A number of factors can increase your risk of having knee problems:

  • Excess weight that will cause increase stress on knee joint.
  • Biomechanical problems, such as having one leg shorter than the other, misaligned knees or even flat feet.
  • Lack of muscle flexibility or strength.
  • Certain sports
  • Previous injury

Types of Knee Pain

In general, knee pain is either immediate (acute) or long-term (chronic). Acute knee pains can be caused by an acute injury or infection. Chronic knee pain is often from injuries or inflammation (such as arthritis) but can also be caused by infection.

Acute Knee Pain

Sprained and Torn Cruciate Ligaments

  • Description: The cruciate ligaments are the structures that connects the bones in the thighs to the legs. There are three cruciate ligaments, the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL) and the medial cruciate ligament (MCL).  Injuries to these ligaments are caused by certain activities that involves twisting or sudden stopping, especially during sports.  The most common ligament injured is the ACL.
  • Symptoms:
    • You may hear a pop
    • Knee give way or become unstable
    • Severe pain
    • Marked knee swelling
  • Treatment: Conservative treatment, such as knee brace and rest, is advised for non-athletes. Athletes or those who undergo stress on there knees may need surgery.

Tendon Ruptures

  • Description: Both the quadriceps and patellar tendons may rupture partially or completely. Injury is due to sports or weakness due to previous surgery or steroid injections to the knees.
  • Symptoms:
    • Pain (especially when trying to kick or extend the knee)
    • Complete ruptures are unable to extend the knee
    • Patella is out of place
  • Treatment: Tendon ruptures generally require surgical repair. A partial rupture may be treated with splinting alone.

Meniscal Injuries

  • Description: Injuries to the meniscus are typically traumatic injuries but can also be due to overuse.
  • Symptoms:
    • Knees lock in a particular position
    • Knees give way
    • Swelling
  • Treatment: Meniscal injuries often require arthroscopic surgical repair.

Knee Dislocation

  • Description: Dislocation of the knee is caused by a particularly powerful blow to the knee. The lower leg becomes completely displaced with relation to the upper leg.
  • Symptoms:
    • Severely painful
    • Deformity of the knee
    • feeling a dull clunk
  • Treatment: If the knee dislocation has not been put back into place on its own, the doctor will immediately put back the dislocation.

Dislocated Kneecap (patella)

  • Description: A common injury caused by direct trauma or forceful straightening of the leg.
  • Symptoms:
    • Patella is out of place
    • Difficulty bending or stretching knee
  • Treatment: The doctor will move the patella back into place (reduce the dislocation). Even if the patella goes back into place by itself, it needs to be X-rayed for a fracture. The doctor will splint the knee to ensure that the patella will remain in its place until it heals.

Chronic Knee Pain

Arthritis: Arthritis of the knee is an inflammatory disorder of the knee joint that is often painful. Arthritis has many causes.

Knee Osteoarthritis

  • Description: Osteoarthritis (OA) is caused by the wear and tear of the knee joint.
  • Symptoms:
    • Pain
    • Swelling
    • Redness
    • Warm knees
  • Treatment: Treatment is aimed at pain control with over-the-counter pain relievers. Anti-inflammatory medications, either over-the-counter, or by your doctor’s prescription, are also quite helpful.

Rheumatoid Arthritis of the Knee

  • Description: Rheumatoid arthritis (RA) is a an autoimmune disease of the connective tissue that affects many joints often including the knee.
  • Symptoms:
    • Pain in the knees and other joints
    • morning stiffness
  • Treatment: Treatment includes pain medications, anti-inflammatory medications, and prescription drugs (such as Rheumatrex (methotrexate)) aimed at slowing disease progression.

Crystalline Arthritis (gout and pseudogout)

  • Description: This occurs when uric acid crystals build up in the joints.
  • Treatment: Treatment is aimed at controlling inflammation with anti-inflammatory medications, and at aiding the metabolism of the various chemicals that may lead to crystal formation.


  • Description: As a result of trauma, infection, or crystalline deposits, the various bursae of the knee may become inflamed.
  • Symptoms:
    • Painful and often swollen knee from the inflammation of the bursae.
  • Treatment: Treatment will usually include home care with PRICE (Protect, Rest, Ice, Compression, Elevation) therapy and NSAIDs. Severe forms, however, can be treated with periodic steroid injections to the

Infection (or infectious arthritis)

  • Description: Many organisms may infect the knee. Gonorrhea, a common sexually transmitted disease, can infect the knee, as can common organisms residing on normal skin.
  • Symptoms:
    • painful knee swelling
    • fevers and chills
  • Treatment: Treatment usually includes intensive antibiotic therapy and may include aspiration of the joint, or surgical drainage of the infection.


During the physical exam, your doctor is likely to:

  • Inspect your knee for swelling, pain, tenderness, warmth and visible bruising
  • Check to see how far you can move your lower leg in different directions
  • Push on or pull the joint to evaluate the integrity of the structures in your knee

Imaging tests

In some cases, your doctor might suggest tests such as:

  • X-ray. Your doctor may first recommend having an X-ray, which can help detect bone fractures and degenerative joint disease.
  • Computerized tomography (CT) scan. CT scanners combine X-rays taken from many different angles, to create cross-sectional images of the inside of your body. CT scans can help diagnose bone problems and detect loose bodies.
  • Ultrasound. This technology uses sound waves to produce real-time images of the soft tissue structures within and around your knee, and how they are working. Your doctor may want to maneuver your knee into different positions during the ultrasound, to check for specific problems.
  • Magnetic resonance imaging. MRI uses radio waves and a powerful magnet to create 3-D images of the inside of your knee. This test is particularly useful in revealing injuries to soft tissues such as ligaments, tendons, cartilage and muscles.

Lab tests

If your doctor suspects an infection, gout or pseudogout, you’re likely to have blood tests and sometimes arthrocentesis, a procedure in which a small amount of fluid is removed from within your knee joint with a needle and sent to a laboratory for analysis.



Again, treatment for knee pain depends on your specific injury. Mild to moderate injuries that cause knee pain will often resolve on their own, given time. To speed the healing, you can:

  • Rest your knee. Give your knee a rest for a few days and avoid intense activity.
  • Ice your knee to reduce pain and swelling. Do it for 15-20 minutes every 3-4 hours for 2-3 days or until the pain is gone.
  • Compress your knee. Use an elastic bandage, straps or sleeves to keep down swelling or add support.
  • Elevate your knee with a pillow under your heel when you’re sitting or lying down to reduce swelling.
  • Take anti-inflammatory medications. Non-steroidal anti-inflammatory drugs (NSAIDs), like Advil, Aleve, or Motrin, will help with pain and swelling. However, these drugs can have side effects and should be used only occasionally, unless your doctor specifically says otherwise.
  • Practice stretching and strengthening exercises if your doctor recommends them.

To resolve some cases of knee pain, you may need a procedure. People with bursitis sometimes need to have excess fluid drawn from the knee. Injections can be given to settle down inflammation for arthritis. Surgery might be needed to reconstruct ligaments or address unstable cartilage injuries.

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