Elastohydrodynamic lubrication analysis of hip implants with ultra high molecular weight polyethylene cups under transient conditions

Abstract

The transient variation of both the load and speed experienced during walking in an elastohydrodynamic lubrication (EHL) analysis for artificial hip joints employing an ultra high molecular weight polyethylene (UHMWPE) acetabular cup against either a metallic or ceramic femoral head was considered in this study. A general numerical procedure to solve the transient EHL problem in spherical ball-in-socket coordinates, developed in a previous study by Jalali-Vahid and Jin in 2002, was applied under three specific conditions experienced during typical gait cycles, including speed reversal, a sudden load increase and a sudden load decrease. The predicted minimum film thickness was found to stay remarkably constant and similar to that prior to the change in either the load or the angular velocity, despite a large change in these operating conditions. This was attributed to the remarkably effective squeeze-film action of preserving and maintaining the lubricating film developed before the transient variations in either the load or speed. It is therefore possible to neglect the effect of these specific transient variations of load and speed under physiological walking conditions considered in the present study on the predicted film thickness in hip implants with UHMWPE cups.

Keywords

transient elastohydrodynamic lubrication (EHL)artificial hip joint replacement speed reversal squeeze film

Get full access to this article

View all access options for this article.

References

Willert

H. G.

Semlitsch

Reaction of the articular capsule to wear products of artifical joint prostheses. J. Biomed. Mater. Res., 1977, 11, 157–164.

Amstutz

H. C.

Campell

Kossovsky

Clark

I. C.

Mechanism and clinical significance of wear debris-induced osteolysis. Clin. Orthop. Related Res., 1991, 276, 7–17.

Ingham

Fisher

Biological reactions to wear debris in total joint replacement. Proc. Instn Mech. Engrs, Part H: J. Engineering in Medicine, 2000, 214(H1), 21–37.

Unsworth

Dowson

Wright

The frictional behaviour of human synovial joints—Part II. Artificial joints. Trans. ASME, J. Lubric. Technol., 1975, 97(3), 377–382.

Jin

Z. M.

Dowson

Fisher

Analysis of fluid film lubrication in artifical hip joint replacements with surfaces of high elastic modulus. Proc. Instn Mech. Engrs, Part H: J. Engineering in Medicine, 1997, 211(H3), 247–256.

Jalali-Vahid

Jagatia

Jin

Z. M.

Dowson

Elastohydrodynamic lubrication analysis of UHMWPE hip joint replacements. In Thinning Films and Tribological Interfaces, Proceedings of 26th Leeds-Lyon Symposium on Tribology, 2000, pp. 329–339.

Jalali-Vahid

Jagatia

Jin

Z. M.

Dowson

Prediction of lubrication film thickness in UHMWPE hip joint replacements. J. Biomechanics, 2001, 34, 261–266.

Sasada

Mabuchi

Elastohydrodynamic lubrication of total hip prosthesis. In Proceedings of the JSLE International Tribology Conference, Tokyo, Japan, 8–10 July 1985.

Mabuchi

Sasada

Numerical analysis of elastohydrodynamic squeeze film lubrication of total hip prostheses. Wear, 1990, 140, 1–16.

10.

Wang

C. T.

Wang

Y. L.

Chen

Q. L.

Yang

M. R.

Calculation of elastohydrodynamic lubrication film thickness for hip prostheses during normal walking. Tribology Trans., 1990, 33, 239–245.

11.

Jagatia

Jalali-Vahid

Jin

Z. M.

Elastohydrodynamic lubrication analysis of UHMWPE hip joint replacements under squeezer-film motion. Proc. Instn Mech. Engrs, Part H: J. Engineering in Medicine, 2001, 215(H2), 141–152.

12.

Paul

J. P.

Forces transmitted by joints in the human body: Lubrication and wear in living and artifical human joints. Proc. Instn Mech. Engrs, 1967, 181(3J), 8–15.

13.

Jalali-Vahid

Jin

Z. M.

Transient elastohydrodynamic lubrication analysis of UHMWPE hip joint replacements. Proc. Instn Mech. Engrs, Part C: J. Mechanical Engineering Science, 2002, 216(C4), 409–420.

14.

Lombardi

A. V.

Mallory

T. H.

Dennis

D. A.

Komistek

R. D.

Fada

R. A.

Northcut

E. J.

An in vivo determination of total hip arthroplasty pistoning during activity. J. Arthroplasty, 2000, 15(6), 702–709.

15.

Dennis

D. A.

Komistek

R. D.

Northcut

E. J.

Ochoa

J. A.

Richie

In vivo determination of hip joint separation and the forces generated due to impact loading conditions. J. Biomechanics, 2001, 34, 623–629.

16.

Bergmann

Graichen

Rohlmann

Hip contact forces—some important observations. In Proceedings of the IV World Congress on Biomechanics, Calgary, Canada, 4–9 August 2002.

17.

Jin

Z. M.

Dowson

A full numerical analysis of hydrodynamic lubrication in artificial hip joint replacements constructed from hard materials. Proc. Instn Mech. Engrs, Part C: J. Mechanical Engineering Science, 1999, 213(C4), 355–370.

18.

Hooke

C. J.

The minimum film thickness in line contacts during reversal of entrainment. Trans. ASME, J. Tribology, 1993, 115, 191–199.

19.

Dowson

Jin

Z. M.

An analysis of micro-elastohydrodynamic lubrication in synovial joints considering cyclic loading and entraining velocities. In Fluid Film Lubrication—Osborne Reynolds Centenary (Eds Dowson

Taylor

C. M.

Godet

Berthe

), 1987, pp. 375–386 (Elsevier, Amsterdam).

20.

Jin

Z. M.

Dowson

Fisher

Fluid film lubrication in natural hip joints. In Thin Films in Tribology, Tribology Series (Eds Dowson

Taylor

C. M.

Godet

), 1993, pp. 545–555 (Elsevier, Amsterdam).

21.

Chan

F. W.

Medley

J. B.

Bobyn

J. D.

Krygier

J. J.

Numerical analysis of time-varying fluid film thickness in metal-on-metal hip implants in simulator tests. In Alternative Bearing Surfaces in Total Joint Replacement, ASTM STP 1346 (Eds Jacobs

J. J.

Craig

T. L.

), 1998, pp. 111–128 (American Society for Testing and Materials, Philadelphia, Pennsylvania).

22.

Chan

F. W.

Bobyn

J. D.

Medley

J. B.

Krygier

J. J.

Tanzer

The Otto Aufranc award—wear and lubrication of metal-on-metal hip implants. Clin. Orthop. Related Res., 1999, 369, 10–24.