Verilast for Knees

The first knee tested for 30 simulated years of wear performance

A common issue with knee replacements is what surgeons refer to as "wear." As the new surfaces of the implant rub together—up to 2 million times per year in active adults—friction occurs. This leads to scratches which make tiny fragments of plastic and metal material rub off, thus wearing down the implant.

This effect—not unlike the action of a fingernail file—is a main reason why knee implants can "fail," and why a patient may undergo repeat surgery years after the original procedure.

At Smith & Nephew, we worked for more than a decade developing a new technology that addresses this problem for the tens of thousands of young, active patients who need a knee implant that can support their adventurous spirit. In 2001, we introduced our exclusive OXINIUM oxidized zirconium for knee replacements.

OXINIUM material—a patented metal alloy and ceramic hybrid—has proven to be a superior metal for use in knee implants due to its hardness, smoothness and resistance to scratching and abrasion. The superior strength results in significantly less wear than cobalt chrome (historically the material of choice in knee implants).

Some facts that may interest you:

  • OXINIUM material is 4,900 times more abrasion resistant than cobalt chrome, and may last longer than other implants as it reduces more than half of the implant wear common to other knees.

  • OXINIUM material is 20% lighter than cobalt chrome

  • OXINIUM material contains no detectable nickel, the leading cause of negative reactions in patients with metal allergies.

Oxinium + XLPE = Verilast

VERILAST◊ Technology combines our proprietary OXINIUM◊ alloy and highly cross-linked polyethylene (XLPE) to greatly reduce wear. When used with our LEGION◊ Total Knee System, it demonstrated an impressive 81% reduction in wear in simulated lab testing compared to conventional materials. Plus, wear simulation indicates that the LEGION Cruciate Retaining Knee System with VERILAST Technology may last up to 30 years of wear - that's twice the current industry standard of 15 years.

Verilast Comparison