Total Knee Arthroplasty is a common orthopedic procedure used when chronic knee damage significantly limits daily life. The knee is a major weight-bearing joint, and long-term stress, injury, or disease can lead to persistent pain and reduced mobility. Most conditions respond to conservative care, but some may require surgical evaluation. This article outlines key conditions that may lead to Total Knee Arthroplasty and other possible causes of chronic knee pain.

What is a Total Knee Replacement?

Total Knee Arthroplasty, also known as Total Knee Replacement, is a surgical procedure that replaces damaged cartilage and bone in the knee joint with artificial components.

Key points:

• Purpose: Relieve pain, restore joint alignment, and improve function.
• Procedure: Damaged joint surfaces are removed and replaced with prosthetic components made of metal and polyethylene.
• Indication: Patients with severe pain, functional limitation, and radiographic evidence of joint degeneration after failed non-surgical treatment.

Clinical data from orthopedic guidelines show that Total Knee Arthroplasty provides significant pain relief in 85-90% of appropriately selected patients, with prosthesis survival often exceeding 15 years^[1,2].

Top 4 Knee Problems That May Require Total Knee Arthroplasty

Total Knee Arthroplasty is not the first-line treatment. It is considered when structural damage becomes severe,  and symptoms persist.

1. Severe Knee Osteoarthritis

Knee Osteoarthritis is the most common reason for Total Knee Arthroplasty.

• Cause: Progressive cartilage degeneration due to aging, mechanical stress, or obesity.
• Features: Joint space narrowing, osteophyte formation, stiffness, and chronic pain.
• Impact: “Bone-on-bone” contact may develop, resulting in severe mobility limitations.

Epidemiological data show that knee osteoarthritis affects 365 million people worldwide^[3]. In severe cases, Total Knee Arthroplasty may be considered when conservative treatments no longer provide adequate relief.

2.     Inflammatory Arthritis

Includes rheumatoid arthritis and ankylosing spondylitis.

• Cause: Autoimmune-mediated inflammation of the synovium.
• Features: Persistent swelling, joint erosion, deformity, and instability.
• Impact: Progressive joint destruction despite medication in some patients.

Modern biologic therapies reduce progression, but some patients still reach stages where Total Knee Arthroplasty may be evaluated.

3.     Post-traumatic Arthritis

Develops after a knee injury.

• Causes: Ligament tears, intra-articular fractures, or meniscus damage.
• Mechanism: Altered joint mechanics accelerate cartilage wear.
• Impact: Symptoms may appear years after the initial injury.

Patients with prior anterior cruciate ligament injury or tibial plateau fracture have a higher long-term risk of knee replacement surgery.

4.     Severe Varus or Valgus Deformity

Refers to abnormal knee alignment.

• Varus Deformity: Inward angulation, often linked to medial compartment wear.
• Valgus Deformity: Outward angulation, associated with lateral compartment damage.
• Impact: Uneven load distribution accelerates joint degeneration.

Severe deformities may require Total Knee Arthroplasty to restore mechanical alignment and balance soft tissues.

Other Causes of Chronic Knee Pain

Not all knee pain leads to Total Knee Arthroplasty. Many conditions contribute to chronic symptoms:

• Osteonecrosis: Reduced blood supply leads to bone collapse, especially in older adults or steroid users.
• Hemophilic Arthropathy: Repeated joint bleeding causes cartilage destruction.
• Septic Arthritis History: Prior infection can damage joint surfaces and complicate future treatment.
• Obesity-Related Joint Stress: Higher body weight increases mechanical stress across the knee joint.
• Patellofemoral Disorders or Tendon Issues: May cause pain without requiring joint replacement.

These conditions should be carefully evaluated before considering total knee replacement.

When to See an Orthopedic Specialist?

Patients with the following symptoms should seek evaluation:

• Persistent knee pain lasting more than several months.
• Pain that limits walking, climbing stairs, or performing daily activities.
• Joint stiffness or deformity.
• Limited response to medications, physical therapy, or injections.

Total Knee Arthroplasty is typically considered only after non-surgical options fail and imaging confirms severe joint damage.

A Note from SunMoon

For patients and families exploring treatment options for chronic knee conditions or seeking further evaluation to determine whether Total Knee Arthroplasty may be appropriate, SunMoon can help international patients understand treatment pathways and connect with orthopedic evaluation services.

Patients can receive personalized support throughout the evaluation and treatment process. For more information, please visit the SunMoon official website or contact our team directly.

References:

[1] Yiming, X., Mingwei, H., Wei, Z., Muyang, Y., Jin, L., Jin, J., Wenwei, Q., Bin, F., & Xisheng, W. (2025). Over 20-year follow-up result of total knee arthroplasty for knee arthropathy: a single center cohort study. DOAJ (DOAJ: Directory of Open Access Journals). https://doi.org/10.12290/xhyxzz.2024-1090

[2] Woodland, N., Takla, A., Estee, M. M., Franks, A., Bhurani, M., Liew, S., Cicuttini, F. M., & Wang, Y. (2023). Patient-Reported Outcomes following Total Knee Replacement in Patients Aged 65 Years and Over—A Systematic Review. Journal of Clinical Medicine, 12(4), 1613. https://doi.org/10.3390/jcm12041613

[3] World Health Organization: WHO & World Health Organization: WHO. (2023, July 14). Osteoarthritis. https://www.who.int/news-room/fact-sheets/detail/osteoarthritis