Im over 50 years and off late have been having severe pain in my left knee.10 years back i underwent a hysterectomy. ..please advice?

Arthritis: First i assume that you meant menisectomy. Usually after a menisectomy you develop arthritis in the knee joint and it sounds like this is occurring. Staging is important so i would recommend that you see a physician and get some x rays. Then begin conservative treatment as outlined by the aaos treatment guidelines here is the link:http://www.Aaos.Org/research/guidelines/oakrecommendations.Pdf.

Not related: The hysterectomy would not have anything to do with your knee pain. You should see and orthopedic surgeon for your knee.