Quantification of the Contact Area at the Head-Stem Taper Interface of Modular Hip Prostheses.

Florian Witt, Julian Gührs, Michael M Morlock, Nicholas E Bishop
Author Information
  1. Florian Witt: Institute of Biomechanics, TUHH Hamburg University of Technology, 21073 Hamburg, Germany.
  2. Julian Gührs: Institute of Biomechanics, TUHH Hamburg University of Technology, 21073 Hamburg, Germany.
  3. Michael M Morlock: Institute of Biomechanics, TUHH Hamburg University of Technology, 21073 Hamburg, Germany.
  4. Nicholas E Bishop: Institute of Biomechanics, TUHH Hamburg University of Technology, 21073 Hamburg, Germany; Faculty of Life Sciences, HAW Hamburg University of Applied Sciences, Ulmenliet 20, 21033 Hamburg, Germany.

Abstract

Corrosion of modular taper junctions of hip implants may be associated with clinical failure. Taper design parameters, as well as the intraoperatively applied assembly forces, have been proposed to affect corrosion. Fretting corrosion is related to relative interface shear motion and fluid ingress, which may vary with contact force and area. It was hypothesised in this study that assembly forces modify the extent and distribution of the surface contact area at the taper interface between a cobalt chrome head and titanium stem taper with a standard threaded surface profile. Local abrasion of a thin gold coating applied to the stem taper prior to assembly was used to determine the contact area after disassembly. Profilometry was then used to assess permanent deformation of the stem taper surface profile. With increasing assembly force (500 N, 2000 N, 4000 N and 8000 N) the number of stem taper surface profile ridges in contact with the head taper was found to increase (9.2±9.3%, 65.4±10.8%, 92.8±6.0% and 100%) and the overall taper area in contact was also found to increase (0.6±0.7%, 5.5±1.0%, 9.9±1.1% and 16.1±0.9%). Contact was inconsistently distributed over the length of the taper. An increase in plastic radial deformation of the surface ridges (-0.05±0.14 μm, 0.1±0.14 μm, 0.21±0.22 μm and 0.96±0.25 μm) was also observed with increasing assembly force. The limited contact of the taper surface ridges at lower assembly forces may influence corrosion rates, suggesting that the magnitude of the assembly force may affect clinical outcome. The method presented provides a simple and practical assessment of the contact area at the taper interface.

References

Semin Arthroplasty. 2013 Dec 1;24(4):246-254 [PMID: 24610994]
Clin Biomech (Bristol, Avon). 2012 Jan;27(1):77-83 [PMID: 21903309]
J Bone Joint Surg Br. 2008 Jul;90(7):847-51 [PMID: 18591590]
J Bone Joint Surg Am. 2014 Sep 17;96(18):e157 [PMID: 25232087]
J Orthop Res. 2013 Jul;31(7):1116-22 [PMID: 23440943]
J Bone Joint Surg Am. 2008 Aug;90 Suppl 3:89-95 [PMID: 18676942]
J Biomech. 2011 Jun 3;44(9):1747-51 [PMID: 21531416]
J Orthop Res. 2013 Dec;31(12):2032-9 [PMID: 23966288]
J Bone Joint Surg Am. 2006 Jun;88(6):1183-91 [PMID: 16757749]
J Arthroplasty. 1995 Dec;10(6):851-4 [PMID: 8749772]
Proc Inst Mech Eng H. 2008 Jul;222(5):829-35 [PMID: 18756699]
J Arthroplasty. 2014 Sep;29(9):1808-12 [PMID: 24851788]
J Biomech. 2001 Jul;34(7):859-71 [PMID: 11410170]
J Orthop Res. 2013 May;31(5):807-13 [PMID: 23239536]
J Arthroplasty. 2013 Sep;28(8 Suppl):2-6 [PMID: 23910820]
Bone Joint J. 2013 Jun;95-B(6):747-57 [PMID: 23723267]
PLoS One. 2013;8(6):e67127 [PMID: 23840602]
PLoS One. 2013;8(11):e78373 [PMID: 24260114]
Clin Orthop Relat Res. 2013 Dec;471(12):4082-6 [PMID: 23813241]
Biomed Tech (Berl). 2006 Jul;51(2):103-9 [PMID: 16915773]
J Arthroplasty. 2008 Oct;23(7):1080-5 [PMID: 18534479]
Orthopedics. 2013 May;36(5):e666-70 [PMID: 23672921]
J Biomed Mater Res. 1993 Dec;27(12):1533-44 [PMID: 8113241]
Med Eng Phys. 2013 May;35(5):676-83; discussion 676 [PMID: 22940445]
J Bone Joint Surg Am. 2013 Apr 17;95(8):678-85 [PMID: 23595065]
J Orthop Res. 2006 Feb;24(2):271-9 [PMID: 16435360]
J Arthroplasty. 2013 Aug;28(7):1218-23 [PMID: 23523216]
J Bone Joint Surg Br. 2011 Aug;93(8):1011-6 [PMID: 21768621]
J Orthop Res. 2013 Nov;31(11):1677-85 [PMID: 23918742]
J Bone Joint Surg Am. 2011 Dec 7;93(23):2180-8 [PMID: 22159853]
J Bone Joint Surg Am. 2005 Jan;87(1):28-36 [PMID: 15637030]
Bone Joint Res. 2012 Apr 01;1(4):56-63 [PMID: 23610672]
Am J Orthop (Belle Mead NJ). 2008 Feb;37(2):E26-31 [PMID: 18401491]
Lancet. 2012 Mar 31;379(9822):1199-204 [PMID: 22417410]
J Arthroplasty. 2013 Sep;28(8):1430-6 [PMID: 23528556]
J Arthroplasty. 2002 Sep;17(6):773-8 [PMID: 12216033]

MeSH Term

Arthroplasty, Replacement, Hip
Chromium Alloys
Corrosion
Hip Prosthesis
Materials Testing
Prosthesis Design
Prosthesis Failure
Stress, Mechanical
Titanium

Chemicals

Chromium Alloys
Titanium

Word Cloud

Similar Articles

Cited By