The Use of Porous Tantalum for Reconstructing Bone Loss in Orthopedic Surgery

Abstract

Porous tantalum, a novel biomaterial, was approved for use in orthopedic surgery by the Food and Drug Administration (FDA) in 1997. Several preclinical and experimental studies have demonstrated excellent biocompatibility with physical, mechanical, and tissue ingrowth properties conducive for enhanced osseointegration and superior structural integrity. Porous tantalum has high volumetric porosity (75-80 %). The modulus of elasticity of tantalum (3 Gpa) compares favorably to cancellous bone (1.2 GPa) or subchondral bone (2 GPa). Porous tantalum also has a high coeffi cient of friction with a high resistance to compression (50-80 Mpa) and rotational deformity (40-60 Mpa). Tantalum has been used in a wide array of clinical applications in orthopedics including primary and revision joint replacement, tumor reconstructive surgery, spine fusion, management of osteonecrosis of the femoral head, and foot and ankle surgery. Recent studies have demonstrated excellent clinical and radiographic outcomes, even in the presence of extensive bone loss in hip and knee reconstructive surgeries. Its use in spine surgeries and osteonecrosis of the hip has been associated with mixed clinical results. Further clinical studies are necessary to establish its role and refi ne its indications in specifi c orthopedic applications and determine whether the theoretical advantages of porous tantalum can provide long-term biological fi xation and stability. This chapter presents a synopsis of the biomaterial properties and preclinical and clinical studies of porous tantalum in orthopedic surgery.