Silk-Based Implants, a Shift from Metal
Scientists in the United States have undertook the process of trying to replace the metal fixtures; screws, rods, and plates that patients have implanted into their body in the cases of fractured or broken bones. The replacement is made from a natural fiber, silk, an exceptionally strong and versatile protein derived from silkworm cocoons. Leading this research is Samuel Lin, MD, of Division of Plastic and Reconstructive Surgery at BIDMC, and David Kaplan, Tufts chair of biomedical engineering and a leader in the use of silk for biomedical applications. Kaplan and his team have already developed silk based sponges and foams for operation rooms.
Silk has already been used in modern medicine for other implants, one in the Journal of Clinical Investigation, published in July of last year researched the possibility of silk brain implants helping those suffering from epilepsy. Metal implants over time can cause stress to underlying bone, cause stiffness, and can also lead to increased risk of infection. The silk would eventually dissolve in the body, seeing as the composition of the protein is similar to that of bone. What is important to note in the study regarding the replacement of metal plates with silk, is that in the silk implants are successful, it would eliminate the need for surgical removal of the devices, those which can be removed. Also, the silk based screws can deliver antibiotics to help prevent infections from poor healing wounds and promote bone regrowth.
The test so far has only been done on rodents, six laboratory rats, which had a total of 28 silk-based screws implanted into their hind limbs, and then monitored for eight weeks. Through those eight weeks, the screws kept their mechanical integrity, and showed signs of dissolving after those eight weeks. Post-implantation, silk-based screws are extremely advantageous to clinicians due to silk's radiolucent property, they won't show up on an X-ray, allowing for a more accurate assessment of the healing process. This application was originally treatment for facial injuries, which occur at a rate of several hundred thousands each year, but could potentially help millions of people and improve their quality of life.
Posted By Thomas Flores (5)