This common condition can damage joints long before it is detected

What happens in the body with osteoarthritis?

The disease affects cartilage, the protective tissue that serves as a gasket between the bones in your joints, allowing them to slide over each other when you walk, climb stairs, or bend to pick up groceries. It constantly breaks down from exercise and daily activities. “But our body usually knows how to repair itself,” said the director of the Arthritis Center. The fluid surrounding the joints contains enzymes that help cut and remove worn cartilage, while special cells fix minor damage and rebuild cartilage.
But this cycle of breakdown and repair goes awry in people with osteoarthritis. In some patients, these enzymes may be too aggressive in removing cartilage, or the healing process may be much slower than cartilage breakdown. In others, the body experiences damage or stress in the joints, which leads to inflammation. This inflammation tells the cartilage-cutting enzymes that they need to remove the worn tissue. But if the body cannot reverse the inflammation after the repair is complete, it can lead to more cartilage destruction.

Being overweight is one of the biggest risk factors for osteoarthritis. Injuries from sports or repetitive motion also increase the risk of osteoarthritis, as do conditions that are associated with increased inflammation throughout the body, such as diabetes.
Eventually, cartilage loses its ability to cushion bones. This leads to pain, a crackling sensation when moving the joints, reduced range of motion, and swelling. Symptoms of osteoarthritis are most commonly found in weight-bearing joints such as the knee, hip, and lower spine, although they can also occur in the small joints of the fingers or toes.

“Symptoms of osteoarthritis are most commonly found in weight-bearing joints such as the knee, hip, and lower spine, although they can also occur in small joints in the fingers or toes.”

How is osteoarthritis diagnosed?

When a patient presents with joint pain, the provider may start by feeling for swelling, testing the range of motion of the joint, and ordering tests to rule out other problems or types of arthritis.
The current gold standard for diagnosing osteoarthritis is an X-ray, which can show changes in joint structure associated with the disease. The more worn the joint is, the narrower the gap between the bones.

However, by the time these changes appear on an X-ray, the damage to the joint has already been done. X-ray images also do not always correspond to the severity of symptoms or pain experienced by patients. You may have two patients with the same amount of joint space narrowing – something like two to three millimeters on an X-ray – but one patient may have a ton of pain and the other may not.