Clinical Use of Porous Tantalum in Complex Primary Total Knee Arthroplasty

Abstract not available. Introduction provided instead.

Orthopedic implants have historically been manufactured from various materials including cobalt chrome (Co-Cr), titanium, and stainless steel. Regardless of the material, the ultimate goal for implantation has always been to achieve adequate fixation and stability in order to maximize the longevity of the prosthesis. With an increasing number of young, active patients undergoing total joint arthroplasty, the need for optimal biologic fixation and maintenance of bone stock over time is apparent. During the past decade, technological advances have included the development of surface coatings to enhance the stability of the bone-implant
interface; however, biomechanical property limitations of traditional materials have resulted in the production of a porous tantalum, Trabecular Metal (TM) (Zimmer,
Trabecular Metal™ Technology, Parsippany, NJ), that can be effective in a variety of clinical scenarios.¹

Trabecular metal is constructed from tantalum (atomic number 73), which behaves in a relatively inert manner in vivo.² The structure of the material is based upon repeating dodecahedron units, yielding the appearance of native trabecular
bone.³ Its safety record as a biocompatible material, high degree of volumetric porosity, high frictional characteristics, and low Young’s modulus have expanded
its use in orthopedic surgery to offset issues such as peri-implant stress shielding and the inability for immediate weight bearing.

TM has experienced widespread popularity in the arena of craniofacial and dental reconstruction, spinal implant fixation, and total hip and knee reconstruction.⁴ In the field of total joint arthroplasty, the literature is abundant on the use of TM for both primary and revision surgery, especially as it applies to primary total hip arthroplasty (THA), pelvic bone loss, and acetabular revision. However, the utilization of TM for total knee arthroplasty (TKA) has been underrepresented in the literature. Principles generated for the use of TM in THA have been extrapolated to address issues in simple primary and difficult revision TKA. To the
authors’ knowledge, there have been no studies discussing the use of TM in the setting of complex primary TKA.

We propose to demonstrate the clinical use and specific indications for using TM in complex primary total knee arthroplasty.