World’s first all-plastic ankle replacement offers hope for patients with metal allergies

Editor's Note

MedStar Health announced the first successful all-plastic total ankle replacement surgery, performed at MedStar Georgetown University Hospital. According to a September 30 announcement, the 71-year-old patient has a lifelong metal allergy and suffered from advanced joint degeneration in her right ankle, causing significant difficulty in walking.

Dr. Paul Cooper, the orthopedic specialist in foot and ankle surgery who led the procedure, emphasized the extent to which joint replacement options traditionally have been severely limited for those with allergies to metals. Even ankle fusion—an alternative to replacement that leaves the ankle largely immobile—often requires metal components. In this case, the patient benefits from the same pain-relieving and mobility benefits of a metal ankle replacement.

For over 60 years, metal has been the standard material in joint replacements, with only limited success using ceramics, the announcement notes. The introduction of thermomoldable polymers like Poly ether ketone ketone (PEKK) offers a promising alternative.

PEKK, initially developed for aerospace in the 1960s, is strong, lightweight, and has additional benefits such as antibacterial properties, MRI compatibility, and flexibility in shaping during surgery. It has been used for over a decade in partial skull replacements and spinal fusions, making it a natural evolution for orthopedic applications like total ankle replacement.