Porous metals in orthopedic applications - A review

The development of porous metals and coatings for osseointegration has revolutionized the specialty of orthopedics, particularly total joint reconstruction. However, until recently most implants are fabricated utilizing traditional materials (i.e. sintered beads, fiber metal, plasma spray), which have several inherent limitations. Several new highly porous metals have been recently introduced to improve upon the biomaterial properties of traditional coatings, namely porosity, surface coefficient and modulus of elasticity. These new biomaterials have a similar microscopic appearance that is much like cancellous bone, The open-cell structure of these metals affords several intriguing properties, including; high volumetric porosity (60-80%), low moduli of elasticity and high surface frictional characteristics. The self-passivating nature of these metals and complex nanostructures allow for rapid bone ingrowth in multiple applications of orthopedic surgery. The following represents a review of contemporary implants and biomaterial properties in orthopedic surgery for this class of highly porous metals.