For centuries, silk has been used to make beautiful clothes, bedsheets, and draperies. People prize it for its delicacy and softness. But silk also is some tough stuff, as scientists at a new company are proving.
The number of knee replacement surgeries has been rising dramatically around the world. In the U.S., for example, the number of total knee replacement surgeries tripled between 2003 and 2009. A major cause of the upsurge has been the simultaneous rise in obesity, a common factor in knee injuries. Osteoarthritis, which often accompanies obesity, also is a major cause of knee-replacement surgery.
Orthox, a British company founded by a knee surgeon and a life scientist, has been investigating the potential of a silk technology pioneered at Oxford University. The company’s research led to the development of special knee implants made from a material derived from silkworm fibers. Orthox has dubbed the material FibroFix. The implants, as the company explains, allow people who have undergone injuries to the cartilage and meniscus in the knee to “return to a fully active, pain-free lifestyle.”
The implants come in two types — FibroFix Meniscus, which helps repair the meniscus (a fibrous cartilage in the knee), and FibroFix Cartilage, which helps resurface the cartilage that covers the ends of the tibia and the femur (the articular cartilage).
Two benefits of silk are that it doesn’t cause an immune reaction in the body and it degrades slowly. Once the surgeon places the implant in a patient’s knee, it replaces the tissue that was removed during the surgery. The silk implant takes over the function of the removed tissue until the tissue has regenerated naturally.
Recently, Orthox received a major funding award from a British government agency that was established to foster innovation. The funds will enable the company to conduct clinical trials of its new devices.