Knee arthritis is a common type of osteoarthritis (OA). Its extent depends on how much you use your knees and which knee you use most. Unilateral OA affects just one knee, while bilateral knee arthritis affects both.

Knee arthritis is one of the most common types of osteoarthritis (OA). You use your knees for everyday movements and even for stationary postures like standing. It’s easy to see how your knee joints can wear down over time.

The extent of knee arthritis depends on how much you use your knees, and which knee you use most often. Some people get OA in just one knee, which is known as unilateral OA. Bilateral knee arthritis occurs when both knees are affected with OA.

OA is a painful, degenerative condition that can reduce your mobility and make daily tasks difficult to manage. Early diagnosis and treatment may decrease joint damage and improve your overall quality of life.

Symptoms of bilateral knee OA are similar to those of other forms of knee arthritis. You might experience:

  • a flare-up of knee pain
  • swelling in the surrounding area
  • noticeably worse pain in the morning when you wake up
  • worse pain after activity
  • buckling of the knee
  • inability to straighten your knee
  • grinding or snapping noises as you move
  • overall weakness in the knee

While you might experience these symptoms in just one knee with unilateral OA, bilateral knee OA symptoms are noticeable in both knees. You may also notice a higher level of pain associated with bilateral knee OA.

Bilateral knee OA, like other forms of degenerative arthritis, tends to develop over time as your knee joints are subjected to wear and tear. The knees are the largest joints in your body. They contain multiple points of cartilage that help protect the three main bones in each leg:

  • kneecap (patella)
  • shinbone (tibia)
  • thighbone (femur)

Wear and tear of your knee joints results from:

  • repetitive motions
  • overuse
  • being overweight

All of these conditions can wear down the protective cartilage at the points where the kneecap, shinbone, and thighbone connect. Without the cartilage, the bones rub together, which causes pain and inflammation.

According to the American Academy of Orthopaedic Surgeons (AAOS), knee OA mostly affects adults over 50 years old. This is primarily attributed to years of wear and tear of the related joints.

Bilateral knee OA is diagnosed through a combination of physical exams and tests. At your first visit, your doctor will check for redness and swelling in your knees. Your doctor will also ask you about your history of knee pain and any past injuries.

Possible tests include:

Imaging tests are performed on both knees if bilateral knee OA is suspected. Your doctor will also note any differences in how OA has affected one knee versus the other. These details could help influence treatment measures and possible surgery recommendations.

Treating bilateral knee OA is similar to treating other types of OA. Your doctor may first recommend the occasional use of over-the-counter (OTC) medications for flare-ups. Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen, reduce pain and inflammation in the knees. Acetaminophen (Tylenol), on the other hand, reduces pain only. NSAIDs carry increased risk of stomach bleeding and high blood pressure, while long-term use of acetaminophen can affect the liver. Both can also interfere with other medications and supplements you might take.

Severe cases of bilateral knee OA are often best treated with prescription medications. Prescription pain relievers may be helpful if OTC versions don’t work.

Corticosteroid shots are used in cases of severe inflammation. By reducing inflammation, these shots may help you experience less pain overall. The downside is that symptoms can get worse before they get better. Also, long-term use of corticosteroid shots can make your body immune to their effects, and they may even speed up joint damage. For these reasons, the AAOS recommends a maximum of three to four corticosteroid shots per year.

Weight loss is one of the most common recommendations for patients with knee OA who might also be overweight. This may be especially helpful in bilateral knee OA, as your weight is distributed between both knees. Your doctor may recommend a dietitian as well as an exercise plan. Exercising can be difficult at first because of knee pain. Gradually building up your endurance will usually improve bilateral knee symptoms caused by exercise.

Early detection of bilateral knee OA is important to prevent the joint damage in your knees from getting worse. As the disease progresses, the risk for further complications increases.

Some complications of knee OA include:

  • bone spurs
  • decreased knee function
  • lack of ability to perform daily tasks
  • disability, in the most severe cases

Your doctor may recommend surgery to prevent bilateral knee OA-related complications. Your doctor may talk to you about the following types of surgery:

  • knee replacement
  • cartilage grafting, which involves moving cartilage from one part of the knee to another to patch up damage
  • knee osteotomy, a procedure in which the thighbone or shinbone is reshaped

Bilateral knee OA is a disease that progresses slowly, but it causes lasting damage. When caught early, the condition may be managed so that you can stop the degenerative wear and tear. Early intervention may also help prevent disability. Still, OA damage can’t be reversed. The only way to “fix” this type of OA is through knee replacement surgery.

Medical treatments are just one solution to treating bilateral knee OA. You can also take steps to manage your knee pain so you can increase mobility and stay comfortable. Talk to your doctor about the following suggestions for managing knee pain:

  • Exercise. Regular activity helps improve your mood and overall cardiovascular health, while also strengthening the muscles around your knees to help keep them strong and to prevent further joint damage. Choose low-impact activities to reduce knee pressure, such as:
    • walking
    • swimming
    • elliptical training
    • bike-riding
  • Avoid stairs when possible. Going down stairs is especially hard on the knees.
  • Use braces for added support.
  • Apply ice during pain flare-ups.
  • Rest your knees after long periods of activity. While resting might seem counterintuitive to increasing your activity level, it’s important to avoid overworking your knees. Be sure to alternate exercise with rest.