If you have ever felt a sharp ache in your knees or stiffness in your fingers, you have probably heard the terms “arthritis” and “arthrosis” tossed around. Because they sound almost identical and both cause joint pain, many people assume they are the exact same thing. However, they are actually driven by completely different processes inside your body, and knowing the difference is the first step to getting the right relief.

To put it simply, **arthritis** is all about inflammation. It is a broad umbrella term for conditions where your body’s immune system mistakenly attacks the lining of your joints, or where an infection causes sudden swelling, heat, and redness. Arthritis pain can strike at any age and often hurts worst first thing in the morning or even while you are completely resting.

On the flip side, **arthrosis** (which you probably know by its more common name, osteoarthritis) is a matter of physical “wear and tear” over time. Instead of an immune system attack, arthrosis happens when the smooth, protective cartilage cushioning your bones gradually thins out and wears away due to aging, repetitive motion, or old injuries. Without that cushion, bones can painfully rub directly against each other, usually hurting more after a long day of movement and physical activity.

Because the root causes are so different, treating them requires completely separate approaches. Arthritis treatment usually focuses on calming down the body’s overactive immune system and reducing deep chemical inflammation. Meanwhile, managing arthrosis focuses heavily on rebuilding joint mobility, strengthening the surrounding muscles to support the weight-bearing joints, and protecting the remaining cartilage from further breakdown.