Feb 20, 2021

Types of Arthritis that Affect the Knee

There are many different types of arthritis including osteoarthritis, rheumatoid arthritis and post-traumatic arthritis.

Arthritis is one of those conditions that we all begin to dread as we get older. Our knees take a hammering throughout our lives, whether we are active sportspeople, those who have spent a career on their feet, or just going about our daily business.

The most important questions in anyone’s minds are: how do I protect against arthritis, and how do I treat it?

Arthritis that Affect the Knee

First, you need to understand a bit about arthritis. Did you know that there are many different types of arthritis of the knee, each with its own risk factors and treatment possibilities?

Arthritis is a degenerative condition of the bones caused by joint inflammation.

The bones in your knee joint are coated in a layer of slippery cartilage (articular cartilage) that prevents the rough bony surfaces from rubbing together and provides some shock absorption as you walk, run, jump and bend your knees. If this cartilage gets torn or worn away, it exposes the rough bone surfaces.

When bone impacts on bone, it sets in motion a process. First, the bone begins to wear away, sometimes causing misalignment on the joint and leading to problems with mobility.

Your body will try to heal the damaged bone, often leading to bony outgrowths called bone spurs. These can catch and rub in the joint, causing discomfort, swelling, and pinching and affecting smooth movement of the joint.

The early stages of arthritis are easier to treat, so you are always advised to contact a specialist for a careful and accurate diagnosis if you experience ongoing knee pain or stiffness.

The Capital Orthopaedics team of expert orthopaedic surgeons and sports medicine professionals will ensure that you get the best treatment for your knee arthritis. Contact us here to make an appointment.

Common types of arthritis

There are over 100 forms of arthritis – with an array of causes and symptoms. The most common are:


The most common form of arthritis. This is the degeneration of bone caused by deterioration or damage to the articular cartilage and/or the rubbery meniscus pad in the knee.

What causes knee osteoarthritis?

It is usually the result of repetitive actions over a period of time but can be the result of a traumatic injury. Common causes include a wrenching action, which may tear the articular cartilage, the meniscus (rubbery cartilage pads in the centre of your knee joint) or other supporting structures in your knee, such as the anterior cruciate ligament (ACL) or one of the tendons (eg patella tendon).

It can also be caused by wear and tear or repetitive activities such as jumping or deep knee bends.
The risk of getting osteoarthritis is increased by being overweight, bone deformities, ageing and genetics.

What are the symptoms of knee osteoarthritis?

Symptoms of osteoarthritis typically include:

  • Pain during or after exercise
  • Swelling
  • Tenderness
  • Stiffness
  • Weakness
  • Reduced range of motion

How is knee osteoarthritis treated?

Treatment depends on the location of the damage, the extent of the arthritic conditions and the damage to other structures in your knee.

Non-surgically, osteoarthritis can be treated with steroid injections to reduce inflammation, cellular therapies which use your body’s own healing capabilities to stimulate regeneration, and physiotherapy to improve muscle strength and movement.

Surgical options include: removing bone spurs, smoothing the bone surface (debridement) or replacing all or some of the knee joint with prosthetic parts (knee replacement).

Rheumatoid arthritis

This an autoimmune disease caused by your body attacking the lining (synovial membrane) in your joints, leading to inflammation and thickening of the tissue. This can eventually destroy the cartilage and bones, and weaken ligaments, tendons and muscles around your joints.

It affects multiple joints in your body and the inflammation can affect other non-joint structures in your body, including your skin, eyes, heart and kidneys.

What causes rheumatoid arthritis?

There is no known cause for this type of arthritis, but you’re at an increased risk if you have a family history or rheumatoid arthritis, you are overweight or you are a smoker. It most commonly begins in middle age.

What are the symptoms of rheumatoid arthritis?

  • Tender, warm, swollen joints
  • Joint stiffness that is usually worse in the mornings and after inactivity
  • Fatigue, fever and loss of appetite

Symptoms may come and go, or vary in extremity.

How is rheumatoid arthritis treated?


Disease-modifying anti-rheumatic drugs (DMARDs) can help to slow the progression of rheumatoid arthritis and prevent permanent damage to healthy tissue in your body.

Steroids and anti-inflammatories can help reduce the symptoms of inflammation, pain and stiffness in your joints.

Physical therapy

Physiotherapy can help you maintain flexibility and give you pointers to avoid stressing damaged joints. You will be encouraged to exercise regularly to strengthen the muscles around your knees and other joints.


Parts of your joints that have been damaged due to rheumatoid arthritis can be repaired surgically, including:

  • Synovectomy – removing or trimming thickened joint lining (synovium).
  • Tendon repair – tightening and repairing damaged tendons
  • Joint fusion – parts of your knee joint can be fused together to stabilise or realign deteriorated bones.
  • Joint replacement – removing severely damaged bone and replacing it with prosthetic parts.

Post-traumatic arthritis

This form of osteoarthritis typically affects younger people who have had an injury to their cartilage or the bones of their joints.

What causes posttraumatic arthritis?

While the majority of osteoarthritis cases are the result of wear and tear or repetitive actions, any traumatic injury to the structures of your knee can lead to the degeneration of the bones. A torn ACL, torn meniscus or fractured bones can cause sufficient damage to the cartilage and result in arthritis.

What are the symptoms of posttraumatic arthritis?

You are likely to develop pain, swelling, stiffness and weakness around your knee. You may experience other symptoms such as instability, particularly if the original injury hasn’t been resolved.

How is posttraumatic arthritis treated?

Diagnosis is really important for posttraumatic arthritis. Your specialist will take into account your history – if you have had a major impact or wrenching injury to your knee, you are more likely to develop osteoarthritis.

Treatment may involve resolving other issues that might have developed as a result of the injury (eg torn ACL or torn meniscus), as well as treating the resulting osteoarthritis with physiotherapy, anti-inflammatories, cellular therapy or surgery.

If you have any knee pain for more than a few weeks, it is important to get a careful diagnosis from a specialist. At Capital Orthopaedics, we offer a one-stop-shop consultation, scanning and diagnosis service at one of three central London locations.

Our expert team of consultant orthopaedic surgeons, radiologists and physiotherapists will ensure you get the most effective treatment for knee arthritis, with the best chance for long-term resilience. Contact us here to make an appointment.

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