Rosemont, Il – April 8, 2009 –This award-winning study published in the February 2009 Foot & Ankle International, the official journal of the American Orthopaedic Foot & Ankle Society (AOFAS), was the first research done on the biologic effect of extracorporeal shock wave therapy (ESWT) on normal or pathological human tendon cells (tenocytes), specifically in the foot and ankle. The lead author of this study, AOFAS member Lew C. Schon, MD, Director of Foot & Ankle Services at Union Memorial Hospital in Baltimore, is deeply involved in research studies devoted to discovering the causes of chronic tendinopathy of the foot and ankle to more effectively treat this condition non-surgically.
What happens to diseased tendons in the foot or ankle to make them become painful and swollen? Usually, it comes after some type of over use, too much wear and tear. If caught in its early stages, several weeks of rest in an orthopaedic brace or boot may be all that's needed for healing. In more advanced cases sometimes, a tendon ruptures completely and then the only treatment is surgical repair of that tendon or moving another tendon to take over the old ones function. In some instances, the tendon remains swollen and painful resulting in chronic tendinopathy and the chances of it becoming better without surgery diminish.
Dr. Schon said, "Our goal in this study was to understand how we can heal these chronically painful tendons without surgical intervention using shock wave."
Shock wave therapy has been used successfully as a non-surgical treatment for many musculoskeletal diseases, such as plantar fasciitis and Achilles tendinopathy, without knowing exactly "how" it is helping.
Studies have been done in the past on animal cells which differ, however, from the human cell. What made this study unique was its ability to compare healthy and diseased human tendon cells from the same group of patients. As Dr. Schon noted, "We wanted to look at what these human tendon cells are producing when they're healthy versus when they're diseased. With the approval of our patients, we were able to grow these two types of tendon cells in the lab and learn what would be required to convert a diseased cell back to being a healthy cell. In this and other studies, we are able to compare the response of the same patients' tenocytes (healthy and diseased) to various treatments."
He continued," We catalogued the make-up of the diseased cells before receiving shock wave treatment. We then calculated the appropriate dosage of shock waves needed to make the cell proliferate and analyzed that cell after receiving extracorporeal shock wave therapy. Our hypothesis was that the diseased cell would have higher levels of matrix metalloprotease (MMP) and interleukins (ILs) than the healthy cell. MMP is the enzyme which mainly digests the collagen fibers in our body so they can be reused again in development of new collagen. This enzyme plays a great role in tissue breakage as well as other processes in the body. ILs are inflammatory cytokines, which mediate the inflammatory process in the body.
After shock wave therapy, we were able to compare the changes in the cells. We discovered the levels of MMP decreased, which meant that the cells were no longer digesting collagen at the same rate. When these levels were reduced, the cell appeared to behave like a healthy cell. The shock wave therapy has a measurable effect on human tendon cells. "
This study offered a very specific cellular explanation on why shock waves improve chronically diseased tendon cells. "Before we knew it helped, but we didn't know why," Dr. Schon stated. "Understanding how to alleviate damage to a cell is a very dramatic breakthrough clinically, biomechanically and biologically. Our goal is to be able to treat diseased tendon cells faster and better with less-invasive surgical methods. The affect of tendinopathy on people includes pain, dysfunction, reduction in quality of life and often loss of wages. Our study has shown that tendinopathy and other soft tissue related disease are good candidates for shock wave therapy."
Due to the success of this study, Dr. Schon and his co-authors have received a grant to further study all elements of this problem. Dr. Schon is a member of the American Orthopaedic Foot & Ankle Society.
Members of the American Orthopaedic Foot & Ankle Society are orthopaedic surgeons (MD or DO) who have extensive training in the diagnosis, non-surgical care and surgical treatment of the musculoskeletal system, including bones, joints, ligaments, tendons, muscles, and nerves with a special interest in the foot and ankle.
To find an AOFAS orthopaedic surgeon in your area, go to www.aofas.org.