Observing Osteoarthritis

Photo:Duke University Medical Center

Medical center researchers have found that a device developed to scan computer circuit boards for defects can detect the earliest signs of hand osteoarthritis.

The thermal scanner, sensitive enough to detect differences of a tenth of a degree Fahrenheit, revealed that the temperature of finger joints is proportional to the severity of osteoarthritis. The study showed that finger joints are warmer than average--a sign of inflammation--in the first stage of osteoarthritis. X-rays, the standard clinical technique for diagnosing osteoarthritis, produce inconclusive findings at this early stage of the disease, says Virginia Kraus, a rheumatologist and associate professor of medicine at the medical center.

The researchers' temperature scans also showed that, as osteoarthritis symptoms increased in severity, the joints tended to cool. The researchers' analysis showed that the progressively cooler joint temperatures correlate with increasing disease severity revealed in X-rays of the same joints.

Thermal scanning holds promise for detecting osteoarthritis in the first stage of the disease, before joint changes become apparent on X-rays and before symptoms such as pain and joint enlargement appear. "As we learn more about early stages of the disease, I think we'll be able to intervene earlier, when there will be more chance of making a difference," Kraus says.