Osteoarthritis is graded from your symptoms and from the X-ray, using the Kellgren-Lawrence scale. Grade 1 is mild, with an occasional ache and a joint space that is largely preserved. Grade 2 brings more pain with activity and definite bone spurs. Grade 3 means regular pain, stiffness, and clear narrowing. Grade 4 is a severely worn joint, often with pain that disturbs sleep and walking.
The grade guides the conversation. Early grades are usually managed without surgery. Replacement is considered when pain and loss of function remain severe after other treatment.