The GORE-TEX expanded polytetrafluoroethylene prosthetic ligament. An in vitro and in vivo evaluation

For assessment of the accelerated in vitro and in vivo performance of the GORE-TEX Prosthetic Ligament, mechanical testing included cyclic creep and bending fatigue. Elongation of less than 3% after 20,000,000 cycles under load conditions was used to simulate the functioning human anterior cruciate ligament (ACL). Device tensile strength was 4830 N +/- 280 N. The device was tested in 17 sheep as an ACL replacement. No immobilization was used postoperation. Implant time ranged from 0 to 369 days. Joint stability was maintained in all animals. Fixation strength resulting from osseous ingrowth reached an average of 1380 N at a mean implant duration of 218 days. Clinical trials are underway at 15 centers in the United States. The indication for polytetrafluoroethylene (PTFE) reconstruction is chronic insufficiency of the ACL in knees worthy of salvage. The following evaluation of 130 patients at 15 months or less shows improved stability in 129. Two grafts have been removed--one secondary to infection and the other as a result of improper placement.