Knee osteoarthritis is a degenerative disease that affects the cartilage in your knee joint, leading to joint pain, stiffness, and reduced mobility. As the cartilage breaks down, the knee may become less stable and more painful, especially during movement or weight-bearing activities. This type of arthritis is one of the most common forms of osteoarthritis, particularly in older adults.
Diagnosis of knee osteoarthritis typically involves a physical exam and radiographic findings. While there’s no cure for osteoarthritis, various treatment options for knee osteoarthritis are available. These range from physical therapy, knee braces, and pain relief strategies to surgical treatment options like total knee replacement when conservative methods no longer help.
The video below offers a helpful overview of the knee joint, highlighting its structure, including cartilage, ligaments, and the areas most affected by knee OA.
Osteoarthritis is a degenerative joint disease that can affect any joint in the body. It involves the gradual breakdown of the smooth cartilage in your joints, which normally helps bones move easily. The knee joint is especially prone to this wear and tear because it carries much of the body’s weight and is under constant pressure. This is why knee osteoarthritis, also called gonarthrosis, is one of the most common forms of arthritis.
As the condition progresses, cartilage in your knee becomes rough and starts to break down. In severe cases, small pieces of bone or cartilage may loosen and float within the joint. The video below shows how knee osteoarthritis develops, highlighting the damage to cartilage and how it affects the knee joint.
This breakdown narrows the space between the bones, leading to knee pain, swelling, and inflammation. These changes can limit movement and cause pain and stiffness, making everyday activities more difficult. Over time, patients with knee osteoarthritis may experience chronic pain and reduced mobility.
There are different types of osteoarthritis of the knee, depending on which part of the joint is affected:
- Retropatellar osteoarthritis: wear and tear behind the kneecap (femoropatellar joint)
- Medial gonarthrosis: damage to the inner side of the knee joint (femorotibial area), often linked to bow-leg malalignment (varus gonarthrosis)
- Lateral gonarthrosis: damage to the outer side of the joint, sometimes associated with knock-knee alignment (valgus gonarthrosis)
As we age, it’s common to experience wear and tear in the knee joint, known as primary osteoarthritis. However, age isn’t the only risk factor for knee osteoarthritis. Other factors that may increase the risk of osteoarthritis include:
- Hereditary traits
- Being overweight
- One-sided or excessive physical strain, including sports
- Joint malalignment
- Previous injuries
- Inflammation
When osteoarthritis of the knee develops due to an injury, illness, or excessive strain, it’s referred to as secondary knee osteoarthritis. Both primary and secondary knee OA can lead to knee pain, joint stiffness, and reduced mobility. Over time, patients with knee osteoarthritis may experience chronic pain, and some may require physical therapy, knee braces, or even total knee replacement as part of their treatment options.
Knee osteoarthritis often begins with mild knee pain during physical activity. As the condition progresses, the knee joint may become stiff and swollen, making movement more difficult. In advanced stages, patients with knee osteoarthritis may limp or adopt a posture that relieves the joint. These changes are typical symptoms of knee osteoarthritis and can affect daily life.
Depending on the severity, osteoarthritis of the knee is commonly divided into three stages:
- Stage 1: No noticeable symptoms. Changes are usually seen only on an X-ray.
- Stage 2: Pain during movement that improves with rest.
- Stage 3: Constant knee pain, even at rest, along with major limits in mobility.
Recognizing the stages of osteoarthritis helps guide the management of knee osteoarthritis, from early care to more advanced treatment options.
To diagnose knee osteoarthritis, doctors begin with a detailed medical history, asking about knee pain, symptoms, and possible triggers. This is followed by a physical examination to check your gait, range of motion, leg alignment, and leg length. Additional tests may include checking ligament stability, pain response, and taking X-rays of the knee joint to look for signs of cartilage damage or narrowing of the joint space.
In some cases, further imaging such as MRI, CT Scans, or Scintigraphy may be needed to assess the extent of the damage. A knee arthroscopy is another valuable method—it allows doctors to view the inside of the knee joint directly and even treat certain issues during the same procedure.
The video below explains how a knee arthroscopy works and how it helps in diagnosing and managing osteoarthritis of the knee.
Treatment of knee osteoarthritis depends on the severity and stage of the condition. In early stages, conservative treatment options are often effective in helping reduce pain, improve mobility, and slow the progression of knee OA.
These non-surgical steps may include:
- Lifestyle adjustments, such as reducing body weight to ease stress on your knee
- Physical therapy and heat or cold applications to relieve pain and stiffness
- Use of orthopaedic aids like a knee brace
- Medication for pain relief and inflammation
- Acupuncture, when appropriate
- Following OARSI guidelines for the non-surgical management of osteoarthritis
If symptomatic knee osteoarthritis worsens, knee surgical treatment options may be considered. These include:
- Joint-preserving procedures, such as arthroscopy, which can smooth damaged cartilage in your knee and remove loose fragments
- Axial corrections to improve pressure distribution in the medial compartment of the knee
- Joint-replacing surgery, such as total knee replacement, often recommended for adults with knee osteoarthritis in advanced stages
In some cases, radiographic findings of knee OA and evidence of knee osteoarthritis may show circumscribed cartilage lesions, making arthroscopy a suitable option. This can help patients with symptomatic knee osteoarthritis remain pain-free for years.
When conservative treatment no longer helps, a knee replacement surgery may be the best solution. The damaged joint is replaced with a knee prosthesis, restoring function and relieving chronic pain.
Specialists for knee osteoarthritis include experts in orthopaedics, sports medicine or rheumatology. Advanced imaging like MRI or CT is handled by specialists in radiology/nuclear medicine.
Dedicated knee arthrosis clinics focus on orthopaedics, endoprosthetics, and knee surgery, offering comprehensive care for patients with knee arthritis.
