The following laboratory tests may be helpful in determining causes of restless legs syndrome (RLS) or identifying conditions that rule it out. 1  Blood glucose tests for diabetes. 2  Tests for kidney problems. 3  In certain cases, tests for thyroid hormone, magnesium, and folate levels.
Osteoarthritis. Osteoarthritis is the most common form of arthritis in the knee. It is a degenerative,wear-and-tear type of arthritis that occurs most often in people 50 years of age and older, but may occur in younger people, too. In osteoarthritis, the cartilage in the knee joint gradually wears away.he most common types of arthritis are osteoarthritis and rheumatoid arthritis, but there are more than 100 different forms. In 2012, more than 51 million people reported that they had been diagnosed with some form of arthritis, according to the National Health Interview Survey.
The most common form of arthritis, osteoarthritis is a chronic condition characterized by the breakdown of the cartilage that cushions the ends of the bones where they meet to form joints. This breakdown causes the bones to rub against each other, causing stiffness, pain and loss of movement in the joint. In the foot, osteoarthritis most commonly affects the big toe, but it can also affect the midfoot. Rheumatoid arthritis (RA).