My knees are feeling a little numb. I want to start with exercise therapy. Is that okay?

Lately, my knees have been feeling a bit numb and it's especially hard to climb stairs.

In the past, it would get better with just a little exercise, but now it doesn't get better even with rest, and I'm worried because I feel a heavy pulling sensation all the way to my calves.

I felt swelling, so I was confused as to whether it was cartilage wear or early signs of arthritis.

I'm wondering if the hospital can diagnose to some extent with just an X-ray, or if an MRI might be needed to determine the exact condition.

If it is early-stage arthritis, I would also like to know which method would be more effective, such as injection therapy or exercise therapy.

And I'd also like to share with you some management methods that can help reduce pain in daily life.