A patient's knee is shown before treatment (left). At 2 years after joint distraction treatment, the repaired cartilage allows for greater space within the joint.
An external fixation frame is shown here around the degenerative joint. Photos courtesy Dr. Floris P.J.G. Lafeber
The Iowa Ankle Experience Compares
Ankle distraction also has been performed and is being evaluated in a randomized study led by Dr. Annunziato Amendola of the University of Iowa, Iowa City.
“We are interested in posttraumatic osteoarthritis of joints, and the ankle in particular,” said Dr. Amendola, professor in the department of orthopedics and rehabilitation.
The study, which was funded by the National Institutes of Health, prospectively enrolled about 40 patients with posttraumatic ankle OA. They used the same ankle distraction technique as did Dr. Lafeber's group, but patients were randomized to distraction alone or to distraction plus continuous passive joint motion.
“There's lots of evidence indicating that motion is beneficial to a healing joint,” he said. During the course of the study, patients were evaluated clinically and radiographically, and with a special three-dimensional CT scanning technique to look at cartilage regeneration.
All but three patients have now undergone 2- and 3-year evaluations, and the results thus far have been comparable to the results they have had in Utrecht in terms of relief of pain, according to Dr. Amendola. Additional improvements have been seen over time, and patients in the motion group did significantly better at every time point than did the nonmotion group.
“I think this is quite an intriguing technique, and I'm sure you will be hearing more about it in the next few years,” Dr. Amendola said.