Scientists believe they have developed technology that can spot osteoarthritis (OA) at its earliest stages – even before it begins causing joint damage. The detection method, which was reported at the annual meeting of the American Chemical Society in Philadelphia, could also lead to a better understanding of how the disease is initiated and the development and testing of new treatments to stop it, says Alexej Jerschow, PhD, whose lab at New York University developed the new test.
Traditionally, an osteoarthritis diagnosis is made only after joint pain and stiffness becomes persistent and an X-ray shows damage to the joint cartilage. By that time, damage is usually severe. Treatment, at that point, addresses only the symptoms. It does little to slow the disease, which is often relieved only by total joint replacement. “To make a difference you would have to intervene at an early stage, but to be able to intervene at an early stage you would have to be able to diagnose it an early stage,” says Jerschow.
The new method – an osteoarthritis MRI of sorts – uses a modified form of magnet resonance imaging to determine the concentration of molecules known as glycosaminoglycans (GAGs) in the joint cartilage. GAGs are responsible for many of the mechanical properties of cartilage tissue, including its toughness and elasticity. “One of the things that is known is that the concentration of GAGs goes down in [osteoarthritic cartilage],” says Jerschow. “But the reason for this is not really known.”
Jerschow believes the new technique could be available to patients in four to six years. “It’s not that long because it doesn’t require, for example, the administration of an agent. And it is not much more complicated than a traditional MRI,” he says.
The next step is to determine how effectively this osteoarthritis MRI will predict OA in patients and at which stage it will predict it, says Jerschow. “We want to look at patients characterized as being at risk for OA and monitor them over time.” Initially, that will involve people who already have arthritis in one joint, and monitoring GAG concentrations in the corresponding healthy joint to see if they drop.