Arthritis causes swelling and inflammation in the joints and commonly affects the knee. People may also experience knee stiffness, weakness, and cracking noises when moving the knee.

Arthritis is a term that encompasses over 100 conditions that may cause inflammation or swelling of the joints or tissues. Many of these conditions can affect the knee.

This article discusses the different symptoms of knee arthritis and explains which type of arthritis may be causing them. It will also provide information on diagnosis and treatment options.

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Symptoms of arthritis in the knee can include:

  • knee pain and swelling after use, misuse, or trauma
  • knee pain and swelling that worsens after extended periods of inactivity, such as sleeping, sitting, standing, or resting, or at the end of the day
  • knee stiffness and swelling in the knee, which can make it hard to straighten or bend the knee properly
  • a “locking” or “sticking” sensation when moving the knee
  • a creaking, clicking, grinding, or snapping noise when moving the knee
  • pain that may worsen with rainy weather
  • weakness or buckling in the knee

Do symptoms only affect one leg?

Osteoarthritis (OA), reactive arthritis, gout, and post-traumatic arthritis often cause pain in only one joint or one side of the body, although they can affect both sides of the body.

Autoimmune conditions such as lupus and rheumatoid arthritis tend to affect both sides of the body.

Is the pain continuous?

Gout, OA, post-traumatic, reactive, and infectious arthritis can cause continual discomfort during the acute phase of the flare or attack. However, symptoms may be worse on some days than others.

Other forms of arthritis may have symptoms alternating between flare-ups and periods of remission where symptoms improve, such as:

Do symptoms start in a smaller joint?

Many autoimmune conditions, including rheumatoid and psoriatic arthritis, cause initial symptoms in smaller joints before impacting the knee.

Lupus arthritis also does not typically start in the knee. Early symptoms can affect the fingers, wrists, elbows, ankles, and toes.

However, gout, infectious and reactive arthritis, post-traumatic injury, and lupus tend to impact the knee early on.

Learn more about arthritis in the knee here.

The following types of arthritis might affect the knee.


OA is the most common type of arthritis and cause of knee arthritis. It is a degenerative disease that usually impacts people over 50 years old and is characterized by gradual loss of joint cartilage.

OA happens when joint cartilage degrades with age and wear and tear of joints, decreasing the cushioning space between the bones and producing painful growths called bone spurs.

Osteoarthritis can affect any joint in the body and more than one at a time.

Post-traumatic arthritis

Post-traumatic arthritis occurs after injury to the knee. Post-traumatic arthritis can affect the ligaments and cartilage that stabilize and support the joint.


Gout occurs when uric acid crystals deposit in joints, fluids, and tissues. Gout may also impact the ankles or feet.

Learn more about how osteoarthritis in the knee develops here.

Some forms of arthritis can cause symptoms throughout the body. Below is a list of these arthritis types and their symptoms:

Rheumatoid arthritis

  • low-grade fever
  • unexplained exhaustion and fatigue due to anemia
  • eye pain and redness due to inflammation
  • chest pain, shortness of breath, and dry cough due to lung or cardiac involvement
  • numbness and tingling in the arms and legs due to neuropathy

Psoriatic arthritis

  • stiffness and pain in the low back and buttock area
  • itchy, flushed, or silvery skin patches
  • nail changes
  • eye inflammation


Lupus is an autoimmune condition. Arthritis is a common symptom of this disease, which has the following characteristics:

Reactive arthritis

  • genital discomfort with or without lesions
  • gastrointestinal discomfort

Reactive arthritis commonly impacts males aged 20–50 years old.

Infectious arthritis

  • a sudden, severe onset of symptoms
  • swelling
  • fever and chills

However, infectious arthritis most commonly impacts the knees. It rarely affects more than one joint.

Learn more about other autoimmune conditions here.

The best type of treatment for knee arthritis will depend on the cause.

Non-surgical treatment options

Some common non-surgical treatments for OA in the knee include:

  • engaging in regular, low-impact exercise, such as walking, swimming, or cycling
  • applying heat or ice several times daily
  • maintaining a healthy body weight
  • taking over-the-counter (OTC) pain medications, such as acetaminophen
  • minimizing physical activities that put pressure or weight on the knee, such as sitting on the knees, kneeling, or climbing stairs
  • using supportive or assistive devices, such as knee braces, shoe inserts, or a cane
  • applying OTC pain-reducing creams or ointments
  • taking glucosamine and chondroitin sulfate supplements
  • attending physical therapy sessions where a professional therapist can develop an individualized exercise program to increase flexibility and range of motion
  • reducing stress
  • trying alternative therapies, such as acupuncture or magnetic pulse therapy

Prescription treatment options

To manage arthritis, a doctor may also prescribe:

  • pain medications
  • immunosuppressive or disease-modifying medications
  • injections of corticosteroids, which are anti-inflammatory medications, or joint-lubricating supplements every few months
  • antibiotics to treat bacterial infections

Surgical treatment options

If home remedies or prescription medications are not working, a doctor may recommend surgery.

Types of surgery include:

  • Synovectomy: A surgeon will remove the damaged joint lining.
  • Cartilage grafting: A surgeon will use healthy knee cartilage to fill holes in the joint cartilage.
  • Arthroplasty: A surgeon will totally or partially replace the knee joint.
  • Osteotomy: A surgeon will cut or reform the shinbone or thighbone to reduce knee pressure.


Performing strengthening and stretching exercises in addition to low-impact exercises can often help improve joint function and mobility. It can be effective in easing the symptoms of knee arthritis.

It is important to start and then gradually increase repetitions or intensity over time. It is also crucial to continue doing the exercises even after symptoms improve or go away.

Learn more about home remedies for arthritis here.

To diagnose knee arthritis, a doctor will perform a physical examination of the knee and ask about symptoms.

A doctor may also order imaging tests to view the joint’s bones, cavities, and soft-tissues in detail, such as:

Doctors may also run blood tests to check for antibodies or autoimmune markers in the blood associated with arthritis, such as:

Doctors may measure C-reactive protein (CRP) levels and erythrocyte sedimentation rate (ESR) in the blood. This can help to determine whether there is inflammation in the body.

Doctors may also assess small samples of fluids or skin such as:

  • Fluid aspiration and analysis: A sample can help diagnose gout or rheumatoid arthritis.
  • Skin biopsy: A sample can help diagnose psoriatic arthritis and lupus.

Learn more about blood tests for rheumatoid arthritis here.

Osteoarthritis, rheumatoid arthritis, psoriatic arthritis, and post-traumatic arthritis are the most common forms of arthritis to impact the knee. Gout, reactive arthritis, and certain types of bacterial infection can also cause symptoms of knee arthritis.

Contact a doctor to discuss unexplained knee pain, swelling, or other symptoms. Many types of arthritis that tend to impact the knees are progressive or slowly worsen without effective treatment.

It is possible to manage most forms of arthritis with home remedies, lifestyle adjustments, or prescription medications.

In severe cases, some people may require surgery.