Osteoarthritis, also known as degenerative arthritis, is a disease that is caused by the breakdown and eventual loss of the cartilage between one or more joints in the body. Made from protein, cartilage serves to “cushion” the spaces between the bones and joints. There are more than 100 commonly identified arthritic conditions.

Osteoarthritis is the most common of the types, impacting more than 21 million people in the United States alone. The risk of osteoarthritis increases as we age. Before 50, osteoarthritis occurs more often in men. After 50, it tends to occur more frequently in women.   In America, all races appear equally affected. A higher incidence of osteoarthritis exists in the Japanese population, while South African blacks, Southern Chinese and East Indians, tend to have lower rates.

Diagnosis of osteoarthritis centers on two major goals. When diagnosing osteoarthritis, the doctor must first distinguish osteoarthritis from other types of arthritis. It is also crucial to determine whether a patient has primary osteoarthritis or a secondary form of osteoarthritis linked with another disease or condition. Many cases of the disease have no known cause, and are referred to as primary osteoarthritis. Cases in which the cause is known are referred to as secondary osteoarthritis.

An early, precise diagnosis is vital so that proper treatment of osteoarthritis can be provided.

Diagnosis is usually made by taking a thorough personal medical history and examining the medical record. The physician listens for complaints of slowing increasing pain, stiffness, and swelling over a period of years. Sometimes there is a reasonably sudden onset of symptoms, commonly associated with a single episode of trauma (typically a fall) or a period of overuse (lifting too many boxes, weeding the garden, say, or packing to move). Medical history is also accompanied by a physical exam.

An xray examination corroborates the diagnosis. Frequently there will be little correlation between the amount of pain and the severity of the arthritis as shown by the xray. This means that the amount of pain a person experiences is subjective. Some people with a lot of pain may not show much arthritis on xray, while others will show a lot of arthritis but not feel much pain.

A very common early sign of osteoarthritis is a knobby bony deformity, Heberden’s node, which appears at the smallest joint of the end of the fingers. This node was named after a very famous British doctor. The bony deformity is a result of the bone spurs from the osteoarthritis in that joint. Another common bony thickening (node) occurs at the middle joint of the fingers in many patients with osteoarthritis and is called a Bouchard’s node.

Osteoarthritis usually affects the hands, feet, spine, and large weight-bearing joints, such as the hips and knees.