Plastic pushes metal aside in reusable medical device

Medical device manufacturer GMD Inc. has introduced the first reusable trocar that has a thermoplastic handle. The plastic specified, a 20% glass-filled grade of polysulfone, met all necessary specifications and reduced cost by 75% over the previous all-metal version.

Trocars are used to extract fluid, but in this case the device from GMD (Gig Harbor, WA) is used to implant the company's Universal Sling for the treatment of female stress urinary incontinence.

The polysulfone (PSU)-handled instrument replaces an all-metal trocar, which was prohibitively more expensive and more complicated to manufacture and assemble. "Solvay delivered the enabling material technology that made this a game-changer for us," said Shawn Lunney, GMD's VP, sales and marketing, referring to Solvay Advanced Polymers LLC, the supplier of the thermoplastic used, Udel GF-120. The injection molded trocars entered commercial availability last month.

PSU offers the necessary chemical resistance, low shrinkage, and autoclave resistance (a minimum of 50 cycles), on top of the significant cost saving. The reusable trocar consists of a stainless steel needle and inner handle that is overmolded with the Udel PSU. The overmolded instrument offers the weight and feel of metal, along with the reusability and cost effectiveness of plastic. Initial testing of other polymers including glass-filled polycarbonate showed cracking due to residual stress or poor autoclave resistance and poor surface finish.