A New Era in Porous Metals: Applications in Orthopaedics

The development of porous metals and coatings has revolutionized the field of orthopaedics. However, most implants are fabricated utilizing traditional materials (i.e, sintered beads, fiber metal, plasma spray), which have several inherent limitations. Several new porous metals have been recently introduced to improve upon the biomaterial properties of these traditional metals. Tritanium (Stryker, Mahwah, NJ), Regenerex (Biomet, Warsaw, IN), Stiktite (Smith and Nephew, Memphis, TN), and Trabecular Metal (Zimmer, Warsaw, IN) are currently available for use in orthopaedic surgery, all with a characteristic appearance similar to cancellous bone. The open-cell structure of these materials affords several intriguing properties, including; high volumetric porosity (60-80%), low modulus of elasticity, and high frictional characteristics. The following represents a review of the biomaterial properties and applications in orthopaedic surgery for this new class of highly porous metals.