Knee Stiffness, Swollen After Spine Surgery, Stinging Pain In Spine, Chills, No Fever, Night Sweats, Mucous In Stool. Advice?

my knees became stiff, they froze up and swollen and I was unable to squat up and down after spine surgery, and my elbows one by one filled with fluid- all about 90-100 days after the surgery. i was put on Methotrexate , and given kenalog 40 injections in both knees while at tht same time gram stains were done in my knees, and an injection also in my hip. it has been nearly about 1 3/4 years since the initial problem came about with my knees and elbows. I was on the MTX for a couple months, the steroid injections last months I guess. My knees are bad still and are larger and look white with lacy looking dark spots around them. My spine surgery was a large fusion with alot of metal. Some areas did not fuse but the metal was recently removed due to an allergy to it. I have a great deal of stinging/itching pain in spine that gives me the chills sometimes but no fever , but my knees are sometimes so bad I cant sit down or get up.Other symptoms I have are intense sweats especially at night since my 1st spine surgery, and alot of mucous in my stool . I m not sure what is happening..