Joints Destroyed by Natural, Grinding Material

In attempting to treat a patient with a genetic condition known as alkaptonuria (AKU), researchers from the University of Liverpool have shed new light on the destruction involved in osteoarthritis (OA). Along with Professor Alan Boyde and colleagues from Queen Mary University of London, Professor Jim Gallagher in Liverpool found a new mechanism of joint destruction whereby a natural material grinds away healthy cartilage and worsens osteoarthritis (OA).

The scientists found growths known as high density mineralized protrusions (HDMP), heretofore only seen in horses. As stated in the August 11, 2014 news release, these “protrusions are caused as the body acts to fill in cracks in joint cartilage and can snap off, leading to sharp, dense particles in the joint which grind against healthy tissue.”

“To confirm the findings, the team studied eight hips donated for research by people with osteoarthritis and found the same results as in the alkaptonuria patient. The researchers studied the joint without taking out the calcium—a method which is typically used to make bones softer and easier to examine. This process, which involves using acid, would normally have the effect of destroying the HDMPs thus explaining why they have not been recognised before in humans.”

Professor Gallagher concluded in the news release: “Studying a rare illness like alkaptonuria is a worthwhile project in itself, but it can also help with new insights into much more common diseases. This is a case in point, and because of our work on alkaptonuria, we are now able to add a new piece to the puzzle of an illness that affects millions.”

The authors, whose study was published in the Journal of Anatomy, advise that searching for the HDMPs should be included in the study of OA patients.