Abstract

This paper reports on the design and development of a multi-axis (up to 6 axes) mechanical tester for spinal research and testing. The developed spine tester allowed true motion to be simulated on a specimen in pure or combined modes. To demonstrate the capability of the new tester, flexural stiffness properties of sheep lumbar motion segments were evaluated together with a non-contact speckle displacement measurement system. The flexural stiffness of the specimens was measured and compared under constrained and non-constrained testing conditions; with relieving of shear forces (non-constrained), it was found that the specimen behaved in a ‘stiffer’ manner.

1.
Wilke
,
H. J.
,
Claes
,
L. E.
,
Schmitt
,
H.
, and
Wolf
,
S.
,
1994
, “
A Universal Spine Tester for In-vitro Experiments with Muscle Force Simulation
,”
Eur. Spine J.
,
3
, pp.
91
97
.
2.
Wilke
,
H. J.
,
Wolf
,
S.
,
Claes
,
L. E.
,
Arand
,
M.
, and
Wiesend
,
A.
,
1995
, “
Stability Increases of the Lumbar Spine with Different Muscle Groups
,”
Spine
,
20
, pp.
192
198
.
3.
Adams
,
M. A.
,
1995
, “
Mechanical Testing of the Spine—An Appraisal of Methodology Results, and Conclusions
,”
Spine
,
20
(
19
), pp.
2151
2156
.
4.
Wilke
,
H. J.
,
Rohlmann
,
A.
,
Neller
,
S.
,
Schultheiß
,
G.
,
Graichen
,
F.
, and
Claes
,
L. E.
,
2001
, “
Is it Possible to Simulate Physiologic Loading Conditions by Applying Pure Moments?
Spine
,
26
(
6
), pp.
636
642
.
5.
Panjabi
,
M. M.
,
1988
, “
Biomechanical Evaluation of Spinal Fixation Devices: I. A Conceptual Framework
,”
Spine
,
13
, pp.
1129
1134
.
6.
Goel
,
V. K.
,
Clark
,
C. R.
,
Harris
,
K. G.
,
Kim
,
Y. E.
, and
Schulte
,
K. R.
,
1989
, “
Evaluation of Effectiveness of a Facet Wiring Technique: An In-vitro Biomechanical Investigation
,”
Ann. Biomed. Eng.
,
17
, pp.
115
126
.
7.
Panjabi
,
M. M.
,
Duranceau
,
J. S.
,
Oxland
,
T. R.
, and
Bowen
,
C. E.
,
1989
, “
Multidirectional Instabilities of Traumatic Cervical Spine Injuries in a Porcine Model
,”
Spine
,
14
(
10
), pp.
1111
1115
.
8.
Crawford
,
N. R.
,
Brantley
,
A. G.
,
Dickman
,
C. A.
, and
Koeneman
,
E. J.
,
1995
, “
An Apparatus for Applying Pure Nonconstraining Moments to Spine Segment In-vitro
,”
Spine
,
20
, pp.
2097
2100
.
9.
Oxland
,
T. R.
,
Lund
,
T.
,
Jost
,
B.
,
Cripton
,
P.
,
Lippuner
,
K.
,
Jaeger
,
P.
, and
Nolte
,
L. P.
,
1996
, “
The Relative Importance of Vertebral Bone Density and Disc Degeneration in Spinal Flexibility and Interbody Implant Performance
,”
Spine
,
21
, pp.
2558
2569
.
10.
Lund
,
T.
,
Oxland
,
T. R.
,
Jost
,
B.
,
Cripton
,
P.
,
Grassmann
,
S.
,
Etter
,
C.
, and
Nolte
,
L. P.
,
1998
, “
Interbody Cage Stabilization in the Lumbar Spine
,”
J. Bone Jt. Surg.
,
80
(B)-2, pp.
351
359
.
11.
Grassmann
,
S.
,
Oxland
,
T. R.
,
Gerish
,
U.
, and
Nolte
,
L. P.
,
1998
, “
Constrained Testing Conditions Affect the Axial Rotation Response of Lumbar Functional Spinal Units
,”
Spine
,
23
(
10
), pp.
1155
1162
.
12.
Kunz
,
D. N.
,
McCabe
,
R. P.
,
Zdeblick
,
T. A.
, and
Vanderby
,
R.
,
1995
, “
A Multi-Degree of Freedom System for Biomechanical Testing
,”
J. Biomech.
,
116
(
3
), pp.
371
383
.
13.
Cholewicki
,
J.
,
Crisco
,
J. J.
,
Oxland
,
T. R.
,
Yamamoto
,
I.
, and
Panjabi
,
M. M.
,
1996
, “
Effects of Posture and Structure on Three Dimensional Coupled Rotations in the Lumbar Spine
,”
Spine
,
21
, pp.
2421
2428
.
14.
Brown
,
T.
,
Hansen
,
R. J.
, and
Yorra
,
A. J.
,
1957
, “
Some Mechanical Tests on the Lumbosacral Spine with Particular Reference to the Intervertebral Discs
,”
J. Bone Jt. Surg.
,
39A
, pp.
1135
1164
.
15.
Ghosh, P. (ed.), 1988, The Biology of the Intervertebral Disc, Vol. II, CRC Press, Florida, Ch. 1–2.
16.
Adams, M. A., and Hutton, W. C., 1992, Mechanics of the Intervertebral Disc, Vol. II, CRC Press, Florida, pp. 39–71.
17.
Panjabi
,
M. M.
,
Oxland
,
T. R.
,
Yamamoto
,
I.
, and
Crisco
,
J. J.
,
1994
, “
Mechanical Behavior of the Human Lumbar and Lumbosacral Spine as shown by Three-dimensional Load-displacement Curves
,”
J. Bone Jt. Surg.
,
76A
(
3
), pp.
413
424
.
18.
Brinkman
,
P.
, and
Horst
,
M.
,
1985
, “
The Influence of Vertebral Body Fracture, Intradiscal Injection, and Partial Discectomy on the Radial Bulge and Height of Human Lumbar Discs
,”
Spine
,
9
, pp.
138
145
.
19.
Panjabi
,
M. M.
,
Krag
,
M.
,
Summers
,
D.
, and
Videman
,
T.
,
1985
, “
Biomechanical Time Tolerance of Fresh and Cadaveric Human Spine Specimens
,”
J. Orthop. Res.
,
3
, pp.
292
300
.
20.
Wilke
,
H. J.
,
Krischak
,
S.
, and
Claes
,
L. E.
,
1996
, “
Biomechanical Comparison of Calf and Human Spines
,”
J. Orthop. Res.
,
14
, pp.
500
503
.
21.
F. P. Chiang, Q. Wang, and F. Lehman, 1996, “New Developments in Full Field Strain Measurement Using Speckle Photography,” ASTM STP 1318, American Society of Testing and Materials, Philadelphia.
22.
Wilke
,
H. J.
,
Kettler
,
A.
, and
Claes
,
L. E.
,
1997
, “
Are Sheep Spines a Valid Biomechanical Model for Human Spines
,”
Ann. Acad. Sci. Fenn., Ser. A4
,
22
(
20
), pp.
2365
2374
.
23.
Pearcy
,
M. J.
, and
Whittle
,
M. W.
,
1982
, “
Movements of the Lumbar Spine Measured by Three-dimensional X-ray Analysis
,”
J. Biomed. Eng.
,
4
, pp.
107
112
.
24.
Stokes
,
I. A. F.
,
Medlicott
,
P. A.
, and
Wilder
,
D. G.
,
1984
, “
Measurement of Movement in Painful Intervertebral Joint
,”
Med. Biol. Eng. Comput.
,
18
, pp.
694
700
.
25.
Plamondon
,
A.
,
Gagnon
,
M.
, and
Maurais
,
G.
,
1988
, “
Application of a Stereo-radiographic Method for the Study of Intervertebral Motion
,”
Spine
,
13
, pp.
1027
1032
.
26.
Pintar
,
F. A.
,
Cusick
,
J. F.
,
Yoganandan
,
N.
,
Reinartz
,
J.
, and
Mahesh
,
M.
,
1992
, “
The Biomechanics of Lumbar Facetectomy under Compression-flexion
,”
Spine
,
17
(
7
), pp.
804
810
.
27.
Oxland
,
T. R.
,
Lin
,
R. M.
, and
Panjabi
,
M. M.
,
1992
, “
Three-dimensional Mechanical Properties of the Thoracolumbar Junction
,”
J. Orthop. Res.
,
10
, pp.
573
580
.
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