Modern Prostheses for Natural Walking

Ankle Joint Osteoarthritis and Total Ankle Replacement

The ankle joint is particularly susceptible to degeneration such as osteoarthritis, explains Prof. Dr. med. Dr. phil Victor Valderrabano, an internationally well-respected specialist in orthopedic surgery and head physician at the SWISS ORTHO CENTER in Basel, Switzerland.

Interview: Susanne Amrhein, PRIMO MEDICO

Why is the Ankle Joint of All Things so Susceptible to Degenerative Diseases?

Prof. Valderrabano: "On the one hand, the ankle joint has to bear the greatest weight of all joints in the body. On the other hand, it is a very accident-afflicted joint. Strained ligaments often lead to chronic instability. Fractures and cartilage damage can trigger osteoarthritis. But malposition, which cause punctual additional weight bearing in the joint, also leads to degenerative phenomena in the long run".

For Whom is a Total Joint Replacement of the Ankle Advisable, For Whom Is It Not?

Prof. Valderrabano: "An artificial joint replacement is only possible in cases of endstage osteoarthritis and is only in the middle of the treatment chain. In the first step, I always try to treat degenerative phenomena conservatively. In the second step, cartilage reconstruction can be attempted. The patient should not think about a prosthesis before that. This decision must always be made individually upon consultation with the patient. My primary goal is to avoid arthrodesis/fusion, which should only be considered as the very last step when treating osteoarthritis because it creates an unnatural state by immobilizing a mobile part of the body. Arthrodesis prevents the natural transmission of force between the lower leg and the foot, thereby causing new problems in the musculoskeletal system. A modern total ankle joint prosthesis, on the other hand, does not only allow normal activity in the daily routine, but also "low impact" sports such as cycling, hiking, golfing, skiing, swimming, and others. In other words, an artificial ankle joint allows the majority of the affected patients to regain their quality of life. Requirements are sufficient ligament stability and a straight hindfoot, which can be corrected at the same time the prosthesis is inserted. I would only advise against a total ankle joint prosthesis in cases of severe osteonecrosis or significant neuromuscular disorders".

What Induced You to Take Part in Developing Your Own Total Ankle Replacement?

Prof. Valderrabano: „I am not only an orthopedic surgeon, but also a professional biomechanist.  My great desire is to enable my patients to move as naturally as possible. Therefore, together with three American colleagues, the existing prosthesis models were further developed by taking up the problems of older replacements. Since osteoarthritis in the ankle often affects active people who want to continue hiking, bicycling, or playing tennis, we made sure that the prostheses offer good materials, good anatomy and fastening possibilities, in order to feature the best possible natural biomechanics.

Which Feedbacks Have You Received So Far Regarding Your New Total Ankle Replacement?

Prof. Valderrabano: „The new total ankle replacement have been accepted very well and allow a promising prognosis. We can now achieve service life of 15 years and more with total ankle joint prostheses.  If the total ankle replacement unexpectedly becomes loose or other problems appear, it can be replaced by a revision prosthesis or be turned into an arthrodesis then. 

What Are the Challenges of Inserting a Total Ankle Replacement?

Prof. Valderrabano: "In contrast to the rather simple arthrodesis of the joint, the insertion of a total ankle prosthesis requires special skills and demands a lot from the surgeon. The surgery is difficult because mechanical conditions have to be taken into account. In many cases it is necessary to reconstruct the ligaments or correct the bone in the same surgery. In 30 to 40 percent of all total ankle joint replacement, additional surgeries are necessary. Therefore, this intervention definitely belongs in the hands of specialists".

CONTACT:
Prof. Dr. med. Dr. phil. Victor Valderrabano, MD PhD
SWISS ORTHO CENTER
Schmerzklinik Basel, Swiss Medical Network
Hirschgässlein 15, 4010 Basel, Schweiz
Phone +41 61 295 88 80, Fax +41 61 295 89 74vvalderrabano@gsmn.ch 
www.swissorthocenter.ch