Knee osteoarthritis (OA) is a common condition that affects millions of people, causing pain, stiffness, and reduced mobility. As the protective cartilage in the knee wears down over time, the bones begin to rub against each other, leading to discomfort that can significantly impact daily life. Understanding the different stages of knee osteoarthritis is crucial for identifying symptoms early and seeking appropriate treatment.
In this blog, we’ll explore the four stages of knee osteoarthritis, their symptoms, and the treatment options available to help manage the condition and maintain an active, pain-free lifestyle.
Knee osteoarthritis (OA) is a degenerative joint disease that occurs when the protective cartilage that cushions the ends of the bones wears down over time. This condition primarily affects older adults, but it can also develop in younger individuals who have experienced knee injuries or who are predisposed due to genetics or lifestyle factors. The knee joint is especially susceptible to osteoarthritis because it bears much of the body's weight, making it vulnerable to wear and tear over the years. As the cartilage erodes, the bones begin to rub against each other, leading to pain, swelling, stiffness, and reduced mobility.
Osteoarthritis is one of the most common causes of knee pain and can significantly impact a person’s quality of life. While aging is the primary risk factor, other factors like obesity, previous joint injuries, repetitive stress on the knee, and a sedentary lifestyle can increase the likelihood of developing OA. Over time, the condition can make everyday tasks, such as walking, climbing stairs, or standing for long periods, increasingly difficult. Understanding the progression of osteoarthritis and identifying the early signs are crucial for managing symptoms and slowing the disease's advancement, which is why recognising the four stages of knee OA is so important.
In Stage 1 of knee osteoarthritis, the symptoms are usually quite mild, and many people may not even realise they have OA. Some individuals might experience occasional stiffness or slight pain after physical activity or upon waking in the morning, but these symptoms are often mistaken for general ageing or fatigue. The discomfort at this stage is minor, and daily activities are not significantly affected.
While symptoms may be subtle, an X-ray can reveal the early signs of osteoarthritis. In Stage 1, small bone spurs, known as osteophytes, may be visible on imaging. However, the joint space is typically well-preserved, and cartilage remains largely intact, meaning the joint can still function relatively normally.
Even at this early stage, addressing knee osteoarthritis is important to slow its progression. Treatment primarily focuses on lifestyle modifications that promote joint health and reduce strain on the knee.
Low-impact exercises can help strengthen your knee and reduce pain, including swimming or cycling, as well as a range of exercises that target the muscles in your leg. In some cases, physical therapy may be introduced to strengthen the muscles around the knee, offering additional support to the joint.
Weight management is also critical, as excess body weight can hasten the degeneration of the knee joint.
In Stage 2 of knee osteoarthritis, symptoms become more noticeable, although they are still relatively mild. Individuals may experience more frequent pain, especially after long periods of standing, walking, or other physical activities. Stiffness in the knee joint is also more pronounced, particularly in the morning or after sitting for extended periods. Despite the discomfort, most people can continue with daily activities without significant limitations, although they may notice the pain more regularly.
At this stage, the wear-and-tear on the knee joint is more visible on X-rays. There is a noticeable narrowing of the joint space, which indicates the breakdown of cartilage. Bone spurs are more prominent than in Stage 1, and while the cartilage is beginning to wear down, there is still enough present to cushion the bones and allow for relatively smooth movement of the joint.
Treatment in Stage 2 typically aims to manage pain and maintain joint function. Over-the-counter pain relievers, such as non-steroidal anti-inflammatory drugs (NSAIDs), are commonly recommended to reduce discomfort and inflammation. Low-impact exercises, like walking or cycling, can help maintain joint flexibility and muscle strength around the knee. Strengthening exercises focusing on the quadriceps and hamstrings are especially useful for providing knee stability. In addition, using supportive devices, such as knee braces or compression sleeves, can help reduce strain on the joint and improve mobility. Lifestyle changes, including weight management and maintaining an active lifestyle, continue to play an essential role in slowing the progression of the disease.
By Stage 3, knee osteoarthritis symptoms become significantly more noticeable, and the pain starts to interfere with daily activities. Individuals may experience frequent pain during simple movements, such as walking, bending, or kneeling. Stiffness is more persistent, and swelling can occur after prolonged use of the knee. The range of motion in the knee may also decrease, making it harder to fully extend or flex the joint.
At this stage, the pain may start to disrupt daily routines, and some people might avoid certain physical activities due to discomfort.
In Stage 3, X-rays typically show a marked narrowing of the joint space due to considerable cartilage loss. Bone spurs are larger, and there is visible joint damage. The reduced cartilage leads to more friction between the bones, causing pain and inflammation. While the knee is still functional, the degradation is significant, and signs of joint degeneration are clearly evident on imaging.
Treatment at Stage 3 focuses on managing pain and preserving joint function. Prescription medications, including stronger anti-inflammatories or pain relievers, may be necessary to control discomfort. Corticosteroid injections into the knee joint can provide temporary relief from pain and inflammation, while hyaluronic acid injections may help lubricate the joint and reduce friction.
Structured physical therapy becomes increasingly important to strengthen the muscles around the knee and improve joint stability. Assistive devices, such as a cane or a knee brace, may be recommended to alleviate pressure on the joint and improve mobility. In some cases, doctors may begin discussing surgical treatment options, such as arthroscopic surgery or genicular artery embolisation, to address any mechanical issues within the joint and relieve symptoms.
Stage 4 is the most advanced stage of knee osteoarthritis, characterised by severe pain and significant limitations in mobility. The pain is often constant, even at rest, and can become debilitating.
Individuals may experience severe stiffness in the knee joint, making it difficult to perform everyday activities like walking, climbing stairs, or even standing for extended periods. Joint instability can also occur, and some people may feel that their knee is "giving way."
Swelling and inflammation are common, and the overall quality of life is significantly affected due to chronic pain and restricted movement.
In Stage 4, X-rays will reveal almost complete loss of cartilage, leading to bone-on-bone contact. The joint space is dramatically narrowed or completely gone, and large bone spurs are present. The lack of cushioning between the bones results in increased friction, which causes intense pain and further damage to the joint. The severity of the joint degeneration is easily visible on imaging, and the knee’s function is severely compromised.
At this stage, conservative treatments are often insufficient to manage symptoms, and more invasive options are typically recommended. The most common treatment for Stage 4 knee osteoarthritis is total knee replacement surgery (total knee arthroplasty). During this procedure, the damaged bone and cartilage are removed and replaced with a prosthetic joint, which helps restore function and reduce pain.
For those who are not candidates for surgery or wish to delay it, there is a minimally invasive alternative to a knee replacement known as genicular artery embolisation.
This treatment, performed by a interventional radiologist, delivers tiny particles, known as embolic agents, directly to the inflammed area via the artery, restricting blood flow. This restriction reduces knee pain, as less blood to the area means less inflammation.
Managing knee osteoarthritis effectively requires a combination of lifestyle changes and medical interventions. Staying active with low-impact exercises, such as swimming or cycling, helps maintain joint flexibility and muscle strength, reducing pressure on the knee joint. Maintaining a healthy weight is equally important, as it alleviates stress on the knees and can slow the progression of cartilage damage.
Regular medical check-ups are essential for monitoring the condition and adjusting treatment as needed. Physical therapy can play a key role in strengthening the muscles around the knee, improving mobility, and managing pain. Assistive devices like knee braces and orthotic inserts can offer additional support and make daily activities more manageable.
Recommended reading: 9 Tips for Managing Knee Osteoarthritis
If you’re experiencing knee pain or suspect you might have osteoarthritis, early intervention is key to managing symptoms and slowing the progression of the disease. At Northern Beaches Interventional Radiology, our expert team offers advanced, minimally invasive treatments tailored to your needs, including genicular artery embolisation to help reduce osteoarthritis pain.
Book a consultation with us today to discuss your symptoms and explore the best treatment options for you.