Active MRI Shows How Joints Work


March 18,2014

Since its introduction in the 1980s, magnetic resonance imaging machines, commonly known as MRI scanners, have become a highly valuable tool in diagnostic medicine. Researchers in California now say they have developed a new method that enables them to see moving images of body joints.

With the MRI scanner, the part of the patient’s body that needs to be observed is exposed to a very strong magnetic field which excites hydrogen atoms in its tissues.

Different tissues emit different radio frequencies which a computer turns into images. For the image to be as clear as possible, the patient has to lie perfectly still.

Researchers at the University of California Davis developed a procedure for getting moving images of body parts, like joints.

Professor Robert Boutin, who leads the research team, says the procedure called ‘Active MRI’, captures multiple images per second. Those images, he says, will help doctors analyze the mechanics of the patient's joint before and after the surgery.

“One thing that is important is that we can personalize the exam to address what is causing symptoms to the patient, rather than doing the same thing for everyone," Boutin said.

As one observed patient moves his wrist, one of the most complicated joints in a human body, the image clearly shows the interaction of all the parts involved.

The new procedure has already helped him find out what is causing problems for his patients, said orthopaedic surgeon Robert Szabo.

“We can understand why one person develops an unstable wrist, why one person has pain and wears out the joint surface in one area of the wrist and what we can do to replace, make better products over even make soft tissue corrections to improve that patients life.”

Boutin said ‘Active MRI’ will also help doctors better understand all other moving parts of the body.

“I think that it could and should be applied to every other joint in the body, not only other joints, but muscles and tendons," he said. "We are built to move and I think that MR imaging should reflect that.”

Doctors say they expect further improvements in the new technology that could also help make better prosthetics for amputees.