Medial compartmental osteoarthritis (OA) is a type of OA that affects only the medial compartment part of your knee. It can be managed with low impact exercise, weight loss, and medications.

OA usually results from wear and tear as people get older, but it can also result from excessive use or injury.

There is no cure for OA, and symptoms usually worsen over time. However, there are ways to manage the symptoms. In this article, learn more about this condition and the treatment options.

The three compartments that make up the knee are the:

  • lateral compartment, which is on the outer side of the knee
  • medial compartment, which is near the middle of the knee, on the inner side
  • patellofemoral compartment, which consists of the kneecap and part of the femur

OA can affect one or more of these compartments. If it affects all three compartments, it is called tricompartmental OA.

In general, OA affecting the knee is more common than OA affecting other joints, and according to a 2021 meta-analysis of 16 studies, 17% of OA cases are tricompartmental.

In another 2021 study of a community in China, researchers also found the prevalence of medial compartmental OA, specifically, to be 16% compared to 4.3% for lateral compartmental OA.

The symptoms of medial compartmental OA are similar to those of other types of OA of the knee.

They tend to develop over time and include:

  • pain that gets worse over time, especially with activity
  • stiffness, especially when you wake up in the morning
  • swelling or inflammation
  • “locking up” after sitting for a while
  • symptoms that are more noticeable after vigorous activity
  • instability in the knee joint, with the knee pulling toward the middle of the body

Eventually, pain and a loss of mobility can start to affect your quality of life.

The symptoms of medial compartmental OA might be more easily managed than tricompartmental arthritis.

Articular cartilage acts as a cushion between the bones of a joint. OA happens if that cartilage becomes damaged.

Without cartilage, the bones rub together when you move, causing friction and inflammation. This can irritate nerve fibers and cause pain and further damage.

The spaces between the joints may also narrow, and bone spurs can form on the bones in the knee.

You’re more like to develop OA if you have a family history of the condition. Other risk factors include being an older adult or having obesity.

Medial compartmental OA specifically may also result from:

  • a traumatic injury that damages the cartilage
  • knee misalignment
  • overuse of an injured or misaligned knee
  • a meniscus injury, which damages the fibrocartilage between your thighbone and shinbone

To diagnose medial compartmental OA, a doctor will likely:

  • carry out a physical exam
  • ask about your medical history, including any past injuries
  • check for misalignment
  • take an X-ray

An X-ray may show damage to the knee joint or cartilage and will help determine whether OA affects multiple compartments or the medial compartmental only.

Your doctor may recommend seeing a doctor who specializes in OA, such as:

  • a sports medicine specialist
  • an orthopedic surgeon
  • a rheumatologist

Conservative, first-line treatment for medial compartmental OA can combine:

  • Oral over-the-counter (OTC) or prescription medications like over-the-counter acetaminophen (Tylenol) or nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Advil, Motrin).
  • topical ointments or creams
  • heat and cold packs to reduce pain and inflammation
  • exercises to strengthen the muscles that support the knee and maintain flexibility and mobility.
  • Weight loss, if applicable, as experts strongly recommend, to help reduce pressure on the knee joint.
  • Surgery, if other options are no longer effective, is more likely to be a partial knee replacement if OA affects only one part of the knee but can sometimes involve a total knee replacement.

Learn more about the treatments for OA of the knee.

Treating pain

If you’re experiencing pain, it’s a good idea to try OTC pain medications before asking your doctor for a stronger prescription medication.

In addition, research suggests that taking turmeric, which contains curcumin, may help reduce the pain of knee OA.

Here are some additional tips on managing knee pain, especially at night.

Improving mobility

Other options that can help with mobility include:

  • physical or occupational therapy
  • assistive devices, such as a cane or walking frame
  • a brace or knee support

Click here to learn more about muscle-strengthening exercises for the knee and discover how weight loss can help OA here.

The complications of medial compartmental OA are similar to those of OA in general. They include worsening joint pain and an increased chance of additional injury.

In addition, the condition can affect your mobility, which can place limitations on your day-to-day life. This, in turn, can also lead to mood disorders like depression.

More serious complications may include bleeding or infection in the affected joint, pinched nerve, and even bone death.

It’s not necessarily possible to prevent knee OA, regardless of type. Some people may be more genetically prone to the condition.

That said, you can try to reduce some of the risk factors, which may help prevent it or at least slow down the progression if you do have it. This includes:

  • Be careful when doing athletic or physical activities to avoid injuries to the knees.
  • Rest your knee after injury, follow your doctor’s instructions for care, and do physical therapy if recommended
  • Wear a shoe insert or a custom orthotic insert to offload the pressure from the medial compartment
  • Eat a balanced diet
  • Exercise regularly
  • Maintain a healthy weight

Learn more about OA prevention.

There is no cure for medial or other types of OA, but a range of treatment options can help you manage it and reduce or delay the need for surgery.

They can also improve your quality of life and decrease the need for mobility devices.

In addition, staying active and maintaining a healthy weight is crucial for managing medial compartmental OA.