The Inside Of My Knee Hurts What Are Some Causes Of Inside Knee Pain, At Night, Gets Better If I Walk Around, Hurts Again, Repeat Walking?

What are some causes of inside knee pain, at night, gets better if I walk around, hurts again, repeat walking? - the inside of my knee hurts

At the age of 50 years, ACL knee orthoarthristis take painkillers. The night after about 4 sleep at home, I wake up in severe pain in the knee. I have to get up and walk about two or three minutes. Back to bed and after a few hours, I must repeat. Ideas?