What is the most common form of arthritis?

• A. Rheumatoid arthritis
• B. Gout
• C. Psoriatic arthritis
• D. Osteoarthritis

Answer: (D)

Osteoarthritis is the most common form of arthritis, and it reflects a degenerative process of the joint surfaces that accumulates with age and mechanical use. In plain terms, the protective cartilage wears down over time, especially in weight-bearing joints like the knees and hips, and also in the hands with use. As cartilage thins, the underlying bone adapts, leading to joint space narrowing, bone spur (osteophyte) formation, and stiffness.

This form of arthritis stands out because it arises primarily from aging and cumulative joint loading rather than an autoimmune or crystal-driven trigger. That makes it far more prevalent in the general population compared with other types. Rheumatoid arthritis, while important, is autoimmune and less common. Gout involves urate crystal deposition with episodic attacks, and psoriatic arthritis occurs in people with psoriasis and is less common still. The high prevalence of OA, especially as people live longer and many have higher body weight, explains why it is the most frequent arthritis encountered in clinical practice and a common indication for joint replacement surgeries.