Rheumatoid arthritis (RA) is a chronic autoimmune disease primarily affecting the lining of joints, known as the synovium. This condition can lead to pain, swelling, and stiffness in various joints throughout the body, including the knees. RA uniquely impacts the knee joint, influencing considerations for surgical intervention and the outcomes of knee replacement surgery.
How Rheumatoid Arthritis Affects the Knee
Rheumatoid arthritis targets the body’s own tissues, specifically attacking the synovial membrane lining the knee joint. This autoimmune attack triggers chronic inflammation, causing the synovium to thicken and produce excessive joint fluid. The inflamed synovium, often called pannus, then invades and erodes the adjacent cartilage and bone within the joint.
Inflammatory chemicals released during this process further break down cartilage, leading to its erosion and a narrowing of the joint space. This damage extends to the bone beneath the cartilage, contributing to bone erosion and the formation of bone cysts. Unlike osteoarthritis, which is primarily a wear-and-tear condition, RA involves a systemic inflammatory response that actively destroys joint structures.
The persistent inflammation can also weaken the ligaments surrounding the knee, leading to laxity or instability. This structural damage, combined with cartilage and bone destruction, often results in significant pain, stiffness, and deformity, making everyday activities challenging. Such advanced joint destruction often necessitates surgical solutions, like knee replacement.
Preparing for Knee Replacement with RA
Preparing for knee replacement surgery with rheumatoid arthritis involves specific considerations to optimize outcomes. Managing RA disease activity before the procedure is a primary focus to reduce inflammation and minimize complications. This often requires close collaboration between the orthopedic surgeon and the patient’s rheumatologist.
Adjustments to RA medications are frequently necessary. Biologic agents and some disease-modifying antirheumatic drugs (DMARDs) may need to be temporarily stopped before surgery to lower infection risk. Patients on long-term steroid therapy might require stress doses around the time of surgery to prevent adrenal insufficiency.
A multidisciplinary approach is beneficial, involving the rheumatologist, surgeon, and other healthcare professionals to assess overall health. Pre-operative physical therapy can also help strengthen surrounding muscles, supporting recovery. Patients are also advised to prepare their homes for post-surgical mobility and arrange for assistance.
RA’s Influence During and After Surgery
During knee replacement surgery, patients with rheumatoid arthritis may present unique challenges. Chronic inflammation and long-term medication use can lead to poorer bone quality, affecting how well prosthetic components are fixed to the bone. Surgeons may prefer cemented implants for better stability.
Soft tissues around the knee can also be fragile or scarred due to RA, requiring meticulous handling. Ligamentous laxity, common in RA, might necessitate more constrained prosthetic designs to ensure joint stability.
Post-operatively, RA patients face an increased risk of complications, particularly infection. This elevated risk is attributed to the disease and immunosuppressive medications. Wound healing can also be slower.
Physical therapy after surgery is tailored to the specific needs of RA patients, considering their overall disease activity. Aggressive pain management strategies are often employed to facilitate early mobilization, which is important for recovery and preventing stiffness.
Living with a Knee Replacement and RA Long-Term
For individuals with rheumatoid arthritis, a knee replacement can significantly improve function and reduce pain, contributing to a better quality of life. The longevity of knee implants in RA patients is generally positive, with many experiencing satisfactory results for over a decade.
Despite these positive outcomes, long-term complications can occur, including implant loosening or wear of the prosthetic components. RA patients also have a higher long-term risk of infection and may require revision surgery.
Continued rheumatological care is important after knee replacement for RA patients. This ongoing management addresses systemic disease activity and helps monitor for potential late complications related to the implant. Regular follow-ups ensure the best possible long-term functional outcome and overall well-being.