Currently some of these types of screws are being used, but when they disintegrate over a couple years, holes are left, but this new process is supposed to fix that. This is work in progress and the screws are made of composite material close to the properties of real bones so they mesh I believe. It certainly beats a second surgery to remove the pins and screws put in place. BD
Knee ligament damage is an injury all to common to sportsmen and women. The solution usually involves replacing the torn ligament with a piece of tendon from the leg, which is fixed to the bone by means of a titanium or stainless steel screw. Unfortunately, after a certain time another surgery is required to remove them. Now researchers have developed a screw that is bio-compatible and also biodegradable over time, making this second surgery unnecessary.
Biodegradable screws made of polylactic acid are already used in the medical field, but they have the disadvantage that when they degrade they can leave holes in the bone.
The researchers at the Fraunhofer Institute for Manufacturing Engineering and Applied Materials Research (IFAM) in Bremen developed a moldable composite made of polylactic acid and hydroxylapatite, a ceramic which is the main constituent of the bone mineral. This composite promotes the growth of bone into the implant. Depending on the composition the screws will biodegrade in 24 months.