Unfortunately, the knees you’re born with don’t come with a lifetime warranty. When working properly, they give you decades of mobility and help you lift everything from groceries to grandchildren. But, as years pass, arthritis often sets in. It may start with an occasional ache or an uncanny ability to predict rain. At its worst, knee arthritis may prevent you from being active during the day and sleeping at night. That’s why you should know there’s help for knees in need.