My right knee and leg hurt when I don't use my cane because I drag my left foot. My PD symptoms are on my left side. I recently was having a problem with both knees hurting when going up stairs. The x-rays did show some arthritis, but the doctor said the arthritis wasn't very bad and said my pain was chondromalacia patellae, which I found out is also known as housemaid's knee. He gave me some exercises to do to strengthen the muscles.