Joint repair method benefits humans, animals

A new technique that uses heat as part of surgical repair of shoulder injuries promises to help many athletes and others regain shoulder stability.

School of Veterinary Medicine researchers, using animals as subjects, also are investigating the technique’s effect on other joints, such as the knee, and its potential for treating damaged cartilage.

Joint injuries are traditionally difficult to heal because of the type of tissue involved and the need to maintain range of motion. Yet injuries are common because vigorously active individuals subject their joints to repetitive stress.

The heat procedure was discovered accidentally by California surgeons in 1993 when they noticed that indirect application of laser energy during an orthopedic procedure caused joint tissue to shrink, much as a hair recoils when touched by a flame. Extensive research since that time has established thermal energy joint modification as a viable treatment for shoulder joint instability.

The minimally invasive procedure, which involves making two tiny incisions in the shoulder joint, one for an arthroscope and the other for a heat wand, allows quicker recovery than is possible with traditional joint surgery. In this group, individuals experience less pain and attain a better range of motion after surgery.

Mark D. Markel, chair of the Department of Medical Sciences and director of the Comparative Orthopaedic Research Laboratory at the School of Veterinary Medicine, has been intimately involved in the basic research leading to acceptance of thermal energy surgeries.

He says that when heat is applied to the joint, the collagen tissue shrinks and hugs the formerly loose joint, holding it in place. Eventually, the recoiled, shrunken tissue is replaced by new tissue growth. Because the new tissue fills only the amount of space taken by the shrunken collagen, it provides long-term stability to the joint.

In the past, joint problems have been handled with reconstructive surgery. Surgeons would surgically shorten existing ligaments to hold the joint in place, with recovery painful and slow.

Already, this thermal technology is being modified for use in other joints, such as the knee. Taking the procedure a step further, Markel and his colleagues are investigating the use of thermal energy in treating damaged cartilage tissue. Cartilage damage is associated with painfully debilitating conditions such as arthritis.

Markel, a board-certified veterinary surgeon, projects that the technique will benefit dogs and horses as well as human athletes and youngsters. “Veterinary medicine is unique in that what we do benefits both humans and animals,” he says.