What is knee arthritis?
Knee arthritis refers to the progressive degeneration or inflammation of the cartilage within the knee joint. The knee is a large, weight-bearing joint formed by the femur (thigh bone), tibia (shin bone), and patella (kneecap). These bones are covered with a smooth layer of articular cartilage that allows the joint to move freely while absorbing shock during activities such as walking, running, and climbing stairs.
In arthritis, this protective cartilage gradually wears away or becomes damaged, leading to increased friction between the bones. This can result in pain, swelling, stiffness, and reduced joint function. Over time, the joint may develop structural changes such as bone spurs (osteophytes), thickening of the joint lining, and changes in alignment, which can further impair movement and stability.
Causes
The most common cause of knee arthritis is osteoarthritis, which develops gradually with aging, repeated wear and tear, obesity, or past knee injuries such as ligament tears or fractures. Rheumatoid arthritis, an autoimmune condition, can also cause inflammation that damages the knee joint over time. Other causes include gout, infections, and genetic factors that affect joint health. As the cartilage deteriorates, the bones begin to rub together, resulting in inflammation, discomfort, and difficulty performing daily activities such as walking, kneeling, or climbing stairs.
Symptoms
Symptoms of knee arthritis often develop gradually and may worsen over time.
The common symptoms include:
- Pain: in the knee, particularly during weight-bearing activities such as walking, climbing stairs, or standing for prolonged periods
- Stiffness: especially after periods of rest or in the morning
- Swelling: due to inflammation or fluid accumulation within the joint
- Reduced range of motion: making it difficult to fully bend or straighten the knee
- Mechanical: grinding, clicking, or crunching (crepitus) during movement.
- Weakness: or a feeling of instability in the knee
As the condition progresses, pain may become more constant and can begin to interfere with sleep and daily activities. In advanced cases, visible deformity, such as bowing of the legs, may develop.
Treatment
Conservative (non-operative)
Management of knee arthritis is tailored to the severity of symptoms, the degree of joint damage, and the patient’s lifestyle and goals. Initial treatment is typically conservative and aims to relieve pain, improve function, and slow disease progression.
Common non-surgical treatment options for knee arthritis include physiotherapy exercises to strengthen the muscles around the knee, improve flexibility, and support joint stability. Weight management is also important, as reducing body weight can significantly decrease stress on the knee joint and improve symptoms. Patients are often advised to modify activities by avoiding high-impact exercises and choosing low-impact activities such as swimming or cycling. Medications, including nonsteroidal anti-inflammatory drugs (NSAIDs) and other pain-relieving medicines, may help reduce pain and inflammation. In some cases, injections such as corticosteroids to reduce inflammation or visco supplementation with hyaluronic acid may be recommended. These treatments can be effective in managing symptoms, particularly during the early to moderate stages of arthritis.
Surgical Treatment
When non-surgical treatments are no longer effective and knee arthritis significantly impacts quality of life, surgical options may be considered. The choice of procedure depends on the extent and location of the arthritis, as well as the patient’s age, activity level, and overall health. Surgical options may include arthroscopic procedures in selected cases, although their role in treating arthritis is limited. An osteotomy may be performed to realign the bones and redistribute weight away from the damaged area of the joint, particularly in younger patients. In cases where arthritis affects only one part of the knee, a partial knee replacement, also known as unicompartmental knee arthroplasty, may be recommended. For more advanced arthritis involving the entire joint, a total knee replacement, or total knee arthroplasty, may be required. Knee replacement surgery is a well-established and highly effective treatment aimed at relieving pain, restoring joint function, and improving overall quality of life.
Recovery
Recovery involves a structured rehabilitation program focusing on restoring movement, strength, and mobility. Most patients experience significant improvement in pain and function following surgery