Mechanical stability of novel highly porous metal acetabular components in revision total hip arthroplasty.

Highly porous metal acetabular components have emerged for revision hip arthroplasty. However, superior mechanical stability over traditional cementless components has not been demonstrated. Three different cementless acetabular components, including 2 highly porous tantalum designs, were inserted into hemipelvis specimens with a superolateral defect. Mechanical testing was performed to failure using a servohydraulic testing machine. The porous tantalum designs exhibited superior stability over the traditional cementless implant (P < .05). There was no difference in mechanical stability between the rigid modular tantalum shell and the more flexible revision tantalum shell (P > .46). In acetabular revision, highly porous tantalum acetabular components provide superior mechanical stability. However, these results suggest that improved frictional resistance is a more important design feature over implant flexibility with this particular implant.

[1]  A. Hanssen,et al.  Modular Porous Metal Augments for Treatment of Severe Acetabular Bone Loss during Revision Hip Arthroplasty , 2004, Clinical orthopaedics and related research.

[2]  S. H. Weeden,et al.  The use of tantalum porous metal implants for Paprosky 3A and 3B defects. , 2007, The Journal of arthroplasty.

[3]  J. Galante,et al.  Cementless Acetabular Reconstruction in Revision Total Hip Arthroplasty , 2004, Clinical orthopaedics and related research.

[4]  R M Pilliar,et al.  The optimum pore size for the fixation of porous-surfaced metal implants by the ingrowth of bone. , 1980, Clinical orthopaedics and related research.

[5]  Michael Tanzer,et al.  Characteristics of bone ingrowth and interface mechanics of a new porous tantalum biomaterial. , 1999, The Journal of bone and joint surgery. British volume.

[6]  S. Sporer,et al.  The use of a trabecular metal acetabular component and trabecular metal augment for severe acetabular defects. , 2006, The Journal of arthroplasty.

[7]  W H Harris,et al.  Quantification of Implant Micromotion, Strain Shielding, and Bone Resorption With Porous‐Coated Anatomic Medullary Locking Femoral Prostheses , 1992, Clinical orthopaedics and related research.

[8]  J. M. Lee,et al.  Observations on the Effect of Movement on Bone Ingrowth into Porous‐Surfaced Implants , 1986, Clinical orthopaedics and related research.

[9]  Thomas D. Brown,et al.  INTERFACIAL FRICTIONAL BEHAVIOR: CANCELLOUS BONE, CORTICAL BONE, AND A NOVEL POROUS TANTALUM BIOMATERIAL , 1999 .

[10]  A. Cappello,et al.  Mechanical validation of whole bone composite tibia models. , 2000, Journal of biomechanics.

[11]  L Cristofolini,et al.  Mechanical validation of whole bone composite femur models. , 1996, Journal of biomechanics.

[12]  B. Masri,et al.  Porous tantalum uncemented acetabular shells in revision total hip replacement: Two to four year clinical and radiographic results , 2008 .

[13]  J. Callaghan,et al.  Revision of a Cemented Acetabular Component to a Cementless Acetabular Component: A Ten to Fourteen‐Year Follow‐up Study , 2001, The Journal of bone and joint surgery. American volume.

[14]  W. Harris,et al.  Cementless acetabular revision with the Harris-Galante porous prosthesis. Results after a minimum of ten years of follow-up. , 2004, The Journal of bone and joint surgery. American volume.

[15]  B. Morrey.  Joint Replacement Arthroplasty , 2003 .

[16]  C. Bünger,et al.  Tissue ingrowth into titanium and hydroxyapatite‐coated implants during stable and unstable mechanical conditions , 1992, Journal of orthopaedic research : official publication of the Orthopaedic Research Society.

[17]  T D Brown,et al.  Structural properties of a new design of composite replicate femurs and tibias. , 2001, Journal of biomechanics.

[18]  Robert C. Cohen.  A porous tantalum trabecular metal: basic science. , 2002, American journal of orthopedics.

[19]  W. Harris,et al.  Differences in stiffness of the interface between a cementless porous implant and cancellous bone in vivo in dogs due to varying amounts of implant motion. , 1996, The Journal of arthroplasty.

[20]  A. Shirazi-Adl,et al.  Experimental determination of friction characteristics at the trabecular bone/porous-coated metal interface in cementless implants. , 1993, Journal of biomedical materials research.

[21]  R. J. Lewis,et al.  Evaluation of a porous tantalum uncemented acetabular cup in revision total hip arthroplasty: clinical and radiological results of 60 hips. , 2005, The Journal of arthroplasty.