The femoral head deteriorates in osteonecrosis. As a consequence of that, the cortical shell of the femoral head can buckle into the cancellous bone supporting it. In order to examine the buckling scenario we performed numerical analysis of a realistic femoral head model. The analysis included a solution of the hip contact problem, which provided the contact pressure distribution, and subsequent buckling simulation based on the given contact pressure. The contact problem was solved iteratively by approximating the cartilage by a discrete set of unilateral linear springs. The buckling calculations were based on a finite element mesh with brick elements for the cancellous bone and shell elements for the cortical shell. Results of 144 simulations for a variety of geometrical, material, and loading parameters strengthen the buckling scenario. They, particularly, show that the normal cancellous bone serves as a strong supporting foundation for the cortical shell and prevents it from buckling. However, under the development of osteonecrosis the deteriorating cancellous bone is unable to prevent the cortical shell from buckling and the critical pressure decreases with the decreasing Young modulus of the cancellous bone. The local buckling of the cortical shell seems to be the driving force of the progressive fracturing of the femoral head leading to its entire collapse. The buckling analysis provides an additional criterion of the femoral head collapse, the critical contact pressure. The buckling scenario also suggests a new argument in speculating on the femoral head reinforcement. If the entire collapse of the femoral head starts with the buckling of the cortical shell then it is reasonable to place the reinforcement as close to the cortical shell as possible.

1.
Bullough
,
P. G.
, 2004,
Orthopaedic Pathology
,
4th ed.
,
C. V. Mosby
,
New York
.
2.
Brown
,
T. D.
,
Pedersen
,
D. R.
,
Baker
,
K. J.
, and
Brand
,
R. A.
, 1993, “
Mechanical Consequences of Core Drilling and Bone Grafting on Osteonecrosis of the Femoral Head
,”
J. Bone Jt. Surg., Am. Vol.
0021-9355,
75
, pp.
1358
1367
.
3.
Yang
,
J.-W.
,
Koo
,
K.-H.
,
Lee
,
M. C.
,
Yang
,
P.
,
Noh
,
M. D.
,
Kim
,
S. Y.
,
Kim
,
K.
,
Ha
,
Y.-C.
, and
Joun
,
M. S.
, 2002, “
Mechanics of Femoral Head Osteonecrosis Using Three-Dimensional Finite Element Method
,”
Arch. Orthop. Trauma Surg.
0344-8444,
122
, pp.
88
92
.
4.
Spitzer
,
V.
,
Ackerman
,
M. J.
,
Scherzinger
,
A. L.
, and
Whitlock
,
D.
, 1996, “
The Visible Human Male: A Technical Report
,”
J. Am. Med. Inform Assoc.
1067-5027,
3
, pp.
118
30
.
5.
Genda
,
E.
,
Iwasaki
,
N.
,
Li
,
G. A.
,
MacWilliams
,
B. A.
,
Barrance
,
P. J.
, and
Chao
,
E. Y. S.
, 2001, “
Normal Hip Joint Contact Pressure Distribution in Single-Leg Standing—Effect of Gender and Anatomic Parameters
,”
J. Biomech.
0021-9290,
34
, pp.
895
905
.
6.
Bergmann
,
G.
,
Deuretzbacher
,
G.
,
Heller
,
M.
,
Graichen
,
F.
,
Rohlmann
,
A.
,
Strauss
,
J.
, and
Duda
,
G. N.
, 2001, “
Hip Contact Forces and Gait Patterns from Routine Activities
,”
J. Biomech.
0021-9290,
34
, pp.
859
871
.
7.
Yoshida
,
H.
,
Faust
,
A.
,
Wilckens
,
J.
,
Kitagawa
,
M.
,
Fetto
,
J.
, and
Chao
,
E. Y. C.
, 2005, “
Three-Dimensional Hip Contact Area and Pressure Distribution During Activities of Daily Living
,”
J. Biomech.
0021-9290, (in press).
8.
ABAQUS Theory Manual, Version 6.3, 2002, Hibbitt, Karlsson and Sorensen Inc., Pawtucket, Rhode Island.
9.
Brown
,
T. D.
,
Way
,
M. E.
, and
Ferguson
,
A. B.
, 1981, “
Mechanical Characteristics of Bone in Femoral Capital Aseptic Necrosis
,”
Clin. Orthop. Relat. Res.
0009-921X,
156
, pp.
240
247
.
10.
Favenisi
,
J. A.
,
Gardeniers
,
J. W. M.
,
Huiskes
,
R.
, and
Slooff
,
T. J.
, 1984, “
Mechanical Properties of Normal and Avascular Cancellous Bone
,” in
Biomaterials and Biomechanics
,
P.
Ducheyne
,
G.
Vanderperre
, and
A. E.
Aubert
, eds.,
Elsevier
,
Amsterdam
.
11.
Cowin
,
S. C.
, 2001,
Bone Mechanics Handbook
,
2nd ed.
,
CRC Press
,
Boca Raton
.
12.
Leali
,
A.
,
Fetto
,
J.
, and
Hale
,
J.
, 2002, “
Biostructural Augmentation for the Treatment of Osteonecrosis: Rationale, Techniques, and Case Example
,”
J. South Orthop. Assoc.
1059-1052,
11
, pp.
167
171
.
13.
Steinberg
,
M. E.
,
Larcom
,
P. G.
,
Strafford
,
B.
,
Hosick
,
W. B.
,
Corces
,
A.
,
Bands
,
R. E.
, and
Hartman
,
K. E.
, 2001, “
Core Decompression With Bone Grafting for Osteonecrosis of the Femoral Head
,”
Clin. Orthop. Relat. Res.
0009-921X,
386
, pp.
71
78
.
You do not currently have access to this content.