Injection Moulding Asia

Metal-like compound for surgical device

The problem was that that a drill guide had never been made in a disposable plastic form before. Because the device needed to be very stiff and dimensionally accurate to facilitate the delicate surgery, Wright Medical engineers had their doubts as to whether it was even possible to do so, much less at a disposable price.

"We were prepared to manufacture metal drill guides, even though we realised that providing an incomplete disposable kit that needed a separate reusable piece was a less than elegant solution," explained Ryan Belaney, Wright Medical's Product Development Engineer.

US-based RTP recommended its 300 Series glass fibre-reinforced polycarbonate compounds providing ISO 10993 compliance to meet biocompatibility requirements. "We tried them out in a cadaver lab, and all the surgeons agreed that the guides worked very well and performed in the same manner as a metal guide," said Belaney. Wright Medical decided to go with the higher loaded version in order to give surgeons an extra measure of stiffness.

The cost of the material also allowed Wright to manufacture the plastic drill guides for less than half the cost of a metal version. An added bonus was that precolouring the compound gave Wright the ability to brand the device in its custom teal colour to make it visually unmistakable in the marketplace.