Squeeze-film lubrication of the human ankle joint during walking is numerically analyzed, the effect of surface sliding being neglected at this stage. Biphasic mixture models are considered for synovial fluid (an ideal and viscous fluid phases) and for articular cartilage (an ideal interstitial fluid and an elastic porous matrix). In the model, the ideal fluid phase passes through the articular surface and matrix pores. The cartilage matrix is considered both normal and pathological (with primary osteoarthrosis). Calculations show that water and small solutes of synovial fluid imbibe into the articular cartilage during the stance period, while the interstitial fluid of the cartilage exudes and enriches the lubricant during the swing period in a central part of the contact at each step. Soon after the onset of walking, repeatedly near the load culmination of each step, the synovial fluid should be turned into a synovial gel and, shortly after, changed back again into a fluid there. In the pathological case, the protective synovial gel layer is quickly depleted after several steps and the surfaces may come briefly into contact in each cycle. With normal cartilage, however, the protective intermittent gel film (formed briefly at each step) maintains its thickness for a longer time. Normal cartilage also behaves more favorably, when a long walk is broken and then resumed shortly afterwards. With normal articular cartilage, maintenance of a lubricating fluid film is much aided by the cyclic nature of the loading encountered in walking, compared with the steady loading in standing where the fluid film is quickly filtered out into a protective permanent gel film.

1.
McCutchen
,
C. W.
,
1962
, “
The Frictional Properties of Animal Joints
,”
Wear
,
5
, pp.
1
17
.
2.
Walker
,
P. S.
,
Dowson
,
D.
,
Longfield
,
M. D.
, and
Wright
,
V.
,
1968
, “
Boosted Lubrication in Synovial Joints by Fluid Entrapment and Enrichment
,”
Ann. Rheum. Dis.
,
27
, pp.
512
520
.
3.
Maroudas, A., 1969, “Studies on the Formation of Hyaluronic Acid Films,” in Lubrication and Wear in Joints, edited by V. Wright, Sector, London, pp. 124–133.
4.
Mow
,
V. C.
,
Kuei
,
S. C.
,
Lai
,
W. M.
, and
Armstrong
,
C. G.
,
1980
, “
Biphasic Creep and Stress Relaxation of Articular Cartilage: Theory and Experiment
,”
ASME J. Biomech. Eng.
,
102
(
1
), pp.
73
84
.
5.
McCutchen
,
C. W.
,
1959
, “
Sponge-Hydrostatic and Weeping Bearing
,”
Nature (London)
,
184
, pp.
1284
1285
.
6.
Ateshian
,
G. A.
,
Lai
,
W. M.
,
Zhu
,
W. B.
, and
Mow
,
V. C.
,
1994
, “
An Asymptotic Solution for the Contact of two Biphasic Cartilage Layers
,”
J. Biomech.
,
27
(
11
), pp.
1347
1360
.
7.
Hou
,
J. S.
,
Mow
,
V. C.
,
Lai
,
W. M.
, and
Holmes
,
M. H.
,
1992
, “
An Analysis of the Squeeze-Film Lubrication Mechanism for Articular Cartilage
,”
J. Biomech.
,
25
(
3
), pp.
247
259
.
8.
Jin
,
Z. M.
,
Dowson
,
D.
, and
Fisher
,
J.
,
1992
, “
The Effect of Porosity of Articular Cartilage on the Lubrication of a Normal Human Hip Joint
,”
Proc. Inst. Mech. Eng., Part H: J. Eng. Med.
,
206
(
2
), pp.
117
124
.
9.
Hlava´cˇek
,
M.
,
1993a
, “
The Role of Synovial Fluid Filtration by Cartilage in Lubrication of Synovial Joints. I. Mixture Model of Synovial Fluid
,”
J. Biomech.
,
26
(
10
), pp.
1145
1150
.
10.
Hlava´cˇek
,
M.
,
1993b
, “
The Role of Synovial Fluid Filtration by Cartilage in Lubrication of Synovial Joints. II. Squeeze-Film Lubrication: Homogeneous Filtration
,”
J. Biomech.
,
26
(
10
), pp.
1151
1260
.
11.
Hlava´cˇek
,
M.
,
2000
, “
Squeeze-Film Lubrication of the Human Ankle Joint With Synovial Fluid Filtrated by Articular Cartilage With the Superficial Zone Worn Out
,”
J. Biomech.
,
33
(
11
), pp.
1415
1422
.
12.
Macirowski
,
T.
,
Tepic
,
S.
, and
Mann
,
R. W.
,
1994
, “
Cartilage Stresses in the Human Hip Joint
,”
ASME J. Biomech. Eng.
,
116
(
1
), pp.
10
18
.
13.
Soltz
,
M. A.
,
Basalo
,
I. M.
, and
Ateshian
,
G. A.
,
2003
, “
Hydrostatic Pressurization and Depletion of Trapped Lubricant Pool During Creep Contact of a Rippled Indenter Against a Biphasic Articular Cartilage Layer
,”
ASME J. Biomech. Eng.
,
125
(
3
), pp.
585
593
.
14.
Medley
,
J. B.
,
Dowson
,
D.
, and
Wright
,
V.
,
1984
, “
Transient Elasto-Hydrodynamic Lubrication Models for the Human Ankle Joint
,”
Eng. Med.
,
13
, pp.
137
151
.
15.
Cohen, B., Gardner, T. R., and Ateshian, G. A., 1993, “The Influence of Transverse Isotropy on Cartilage Indentation Behavior—A Study of the Human Humoral Head,” Transactions Orthopaedic Research Society, Orthopaedic Research Society, Chicago, IL, p. 185.
16.
Donzelli
,
P. S.
,
Spilker
,
R. L.
,
Ateshian
,
G. A.
, and
Mow
,
V. C.
,
1999
, “
Contact Analysis of Biphasic Transversely Isotropic Cartilage Layers and Correlations with Tissue Failure
,”
J. Biomech.
,
32
(
10
), pp.
1037
1047
.
17.
Schinagl
,
R. M.
,
Gurskis
,
D.
, and
Sah
,
R. L.
,
1997
, “
Depth-Dependent Confined Compression Modulus of Full-Thickness Bovine Articular Cartilage
,”
J. Orthop. Res.
,
15
(
4
), pp.
499
506
.
18.
Akizuki
,
S.
,
Mow
,
V. C.
,
Muller
,
F.
,
Pita
,
J. C.
,
Howell
,
D. S.
, and
Manicourt
,
D. H.
,
1986
, “
Tensile Properties of Knee Joint Cartilage. I. Influence of Ionic Condition, Weight Bearing and Fibrillation on the Tensile Modulus
,”
J. Orthop. Res.
,
4
(
4
), pp.
379
392
.
19.
Setton
,
L. A.
,
Zhu
,
W.
, and
Mow
,
V. C.
,
1993
, “
The Biphasic Poroviscoelastic Behavior of Articular Cartilage: Role of the Surface Zone in Governing the Compressive Behavior
,”
J. Biomech.
,
26
(4–5), pp.
581
592
.
20.
Setton
,
L. A.
,
Elliot
,
D. M.
, and
Mow
,
V. C.
,
1999
, “
Altered Mechanics of Cartilage With Osteoarthritis: Human Osteoarthritis and an Experimental Model of Joint Degeneration
,”
Osteoarthritis Cartilage
,
7
(
1
), pp.
2
14
.
21.
Guilak
,
F.
,
Ratcliffe
,
A.
,
Lane
,
N.
,
Rosenwasser
,
M. P.
, and
Mow
,
V. C.
,
1994
, “
Mechanical and Biochemical Changes in the Superficial Zone of Articular Cartilage in Canine Experimental Osteoarthritis
,”
J. Orthop. Res.
,
12
(
4
), pp.
474
484
.
22.
Dowson, D., and Jin, Z. M., 1987, “An Analysis of Micro-Elastohydrodynamic Lubrication in Synovial Joints Considering Cyclic Loading and Entraining Velocities,” Fluid Film Lubrication—Osborn Reynolds Centenary, Proc. 23th Leeds–Lyon Symposium on Tribology, edited by D. Dowson et al., Elsevier, Amsterdam, 1986, pp. 375–386.
23.
Dowson
,
D.
, and
Jin
,
Z. M.
,
1992
, “
Microelastohydrodynamic Lubrication of Low-Elastic-Modulus Solids on Rigid Substrates
,”
J. Phys. D
,
25
, pp.
A116–A123
A116–A123
.
24.
Ribitsch
,
V.
,
Rainer
,
F.
, and
Schurz
,
J.
,
1982
, “
Rheologische Eigenschaften Gesunder Synovialflu¨ssigkeiten
,”
Rheol. Acta
,
21
(
1
), pp.
81
89
.
25.
Zeidler
,
H.
,
Altman
,
S.
,
John
,
B.
,
Gaffga
,
R.
, and
Kulike
,
W.
,
1979
, “
Rheologie pathologischer Gelenkflu¨ssigkeiten. I. Weitere Ergebnisse zur Viskoelastizita¨t
,”
Rheol. Acta
,
18
(
2
), pp.
151
167
.
26.
Hlava´cˇek
,
M.
,
2001
, “
The Thixotropic Effect of the Synovial Fluid in Squeeze-Film Lubrication of the Human Hip Joint
,”
Biorheology
,
38
(
4
), pp.
319
334
.
27.
Hlava´cˇek
,
M.
,
1997
, “
A Central Film Thickness Formula for Elastohydrodynamic Lubrication of Cylinders With Soft Incompressible Coatings and a Non-Newtonian Piecewise Power-Law Lubricant in Steady Rolling Motion
,”
Wear
,
205
, pp.
20
27
.
28.
Medley
,
J. B.
,
Dowson
,
D.
, and
Wright
,
V.
,
1983
, “
Surface Geometry of the Human Ankle Joint
,”
Eng. Med.
,
12
(
1
), pp.
35
41
.
29.
Hlava´cˇek, M., 2004, “Contact of Cylindrical Surfaces With Elastic Incompressible Coatings,” Proc. of Conf. ‘Engineering Mechanics 2004,’ Svratka, Czech Republic.
30.
Garcia
,
J. J.
,
Alteiro
,
N. J.
, and
Haut
,
R. C.
,
1998
, “
An Approach for the Stress Analysis of Transversely Isotropic Biphasic Cartilage Under Impact Load
,”
ASME J. Biomech. Eng.
,
120
(
3
), pp.
608
613
.
31.
Matthewson
,
M. J.
,
1981
, “
Axi-Symmetric Contact on Thin Compliant Coatings
,”
J. Mech. Phys. Solids
,
29
(
2
), pp.
89
113
.
32.
Ro¨hrle
,
H.
,
Scholten
,
R.
,
Sigolotto
,
C.
,
Sollbach
,
W.
, and
Kellner
,
H.
,
1984
, “
Joint Forces in the Human Pelvis-Leg Skeleton During Walking
,”
J. Biomech.
,
17
(
6
), pp.
409
424
.
33.
Johnson
,
G. R.
,
Dowson
,
D.
, and
Wright
,
V.
,
1977
, “
The Elastic Behavior of Articular Cartilage Under a Sinusoidally Varying Compressive Stress
,”
Int. J. Mech. Sci.
,
19
(
5
), pp.
301
308
.
You do not currently have access to this content.