By Dr. Brian McDonough, Medical Editor

PHILADELPHIA (CBS) – Cartilage actually acts like a cushioning surface in the body and, when it’s damaged, a person can actually have areas of a joint where bone rubs against bone.

The condition is called osteoarthritis and it is a condition that can affect many people as they get older. It often happens in the knee. The most common symptom is, not surprisingly, pain. In addition, with activity, there is a limited range of motion, stiffness, tenderness, and swelling around the knee. Often, people will say they feel as if the knee is going to give out.

Pain medicine can help, as well as physical therapy. Exercise and weight loss can make a big difference, as can sports which are less traumatic.

When we talk about osteoarthritis, part of it is lifestyle and part of it is medical treatment as well.