Effects of the overstressing induced by the harvest of grafts from the patellar tendon on the mechanical properties and morphometry of remaining tendon were studied using a rabbit model. The width of the patellar tendon was reduced by one-fourth or one-half equally removing the medial and lateral portions; by this surgery, the cross-sectional area was decreased by 25 or 50 percent from the original area. After all the rabbits were allowed unrestricted activities in cages for 3 to 12 weeks, their patellar tendons were harvested for mechanical and histological studies. The one-fourth removal induced no significant changes in the mechanical properties, but significantly increased the cross-sectional area. In the case of one-half removal, tensile strength and tangent modulus did not change in some tendons, although the cross-sectional area increased significantly. In the other central half tendons, mechanical strength decreased markedly, while the cross-sectional area increased; hypercellular areas and breakage of collagen bundles were observed in these tendons. These results indicate that the patellar tendon has an ability of functionally adapting to overstressing by changing the cross-sectional area, while keeping the mechanical properties unchanged, if the extent of overstressing is less than 30 percent.

1.
Barnes
G. R. G.
, and
Pinder
D. N.
,
1971
, “
In Vivo Tendon Tension and Bone Strain Measurement and Correlation
,”
J. Biomech.
, Vol.
7
, pp.
35
42
.
2.
Bonamo
J. J.
,
Krinick
R. M.
, and
Sporn
A. A.
,
1984
, “
Rupture of the Patellar Ligament After Use of Its Central Third for Anterior Cruciate Reconstruction. A Report of Two Cases
,”
J. Bone Joint Surg.
, Vol.
66-A
, pp.
1294
1297
.
3.
Burks
R. T.
,
Haut
R. C.
, and
Lancaster
R. L.
,
1990
, “
Biomechanical and Histological Observations of the Dog Patellar Tendon After Removal of Its Central One-Third
,”
Am. J. Sports Med.
, Vol.
18
, pp.
146
153
.
4.
Cabaud
H. E.
,
Feagin
J. A.
, and
Rodkey
W. G.
,
1980
a, “
Acute Anterior Cruciate Ligament Injury and Augmented Repair
,”
Am. J. Sports Med.
, Vol.
8
, pp.
395
401
.
5.
Cabaud
H. E.
,
Chatty
A.
,
Gildengorin
V.
, and
Feltman
R. J.
,
1980
b, “
Exercise Effects on the Strength of the Rat Anterior Cruciate Ligament
,”
Am. J. Sports. Med
, Vol.
8
, pp.
79
86
.
6.
Delee
J. C.
, and
Craviotto
D. F.
,
1991
, “
Rupture of the Quadriceps Tendon After a Central Third Patellar Tendon Anterior Cruciate Ligament Reconstruction
,”
Am. J. Sports Med.
, Vol.
19
, pp.
415
416
.
7.
Hayashi
K.
,
1996
, “
Biomechanical Studies of the Remodeling of Knee Joint Tendons and Ligaments
,”
J. Biomech.
, Vol.
29
, pp.
707
716
.
8.
Hayashi, K., Yamamoto, N., and Yasuda, K., 1996, “Response of Knee Joint Tendons and Ligaments to Mechanical Stress,” in: Biomechanics—Functional Adaptation and Remodeling, Hayashi, K., Kamiya, A., and Ono, K., eds., pp. 185-212, Springer-Verlag, Tokyo.
9.
Kamps
B. S.
,
Linder
L. H.
,
DeCamp
C. E.
, and
Haut
R. C.
,
1994
, “
The Influence of Immobilization Versus Exercise on Scar Formation in the Rabbit Patellar Tendon After Excision of the Central Third
,”
Am. J. Sports Med.
, Vol.
22
, pp.
803
811
.
10.
Laros
G. S.
,
Tipton
C. M.
, and
Cooper
R. R.
,
1971
, “
Influence of Physical Activity on Ligament Insertions in the Knees of Dogs
,”
J. Bone Joint Surg.
, Vol.
53-A
, pp.
275
286
.
11.
Lewis
J. L.
,
Lew
W. D.
, and
Schmit
J.
,
1982
, “
A Note on the Application and Evaluation of the Buckle Transducer for Knee Ligament Force Measurement
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
104
, pp.
125
128
.
12.
Linder
L. H.
,
Sukin
D. L.
,
Burks
R. T.
, and
Haut
R. C.
,
1994
, “
Biomechanical and Histologic Properties of the Canine Patellar Tendon After Removal of Its Medial Third
,”
Am. J. Sports Med.
, Vol.
22
, pp.
136
142
.
13.
Majima
T.
,
Yasuda
K.
,
Fujii
T.
,
Yamamoto
N.
,
Hayashi
K.
, and
Kaneda
K.
,
1996
, “
Biomechanical Effects of Stress Shielding of the Rabbit Patellar Tendon Depend on the Degree of Stress Reduction
,”
J. Orthop. Res.
, Vol.
14
, pp.
377
383
.
14.
May, K. D., Horibe, S., and Woo, S. L. -Y., 1989, “The Effects of Long-Term Intensive Exercise and Age on the Biomechanical Properties of Canine Flexor Tendons,” in: 1989 Biomechanics Symposium, Torzilli, P. A., and Friedman, M. H., eds., pp. 73–76, ASME, New York.
15.
Sachs
R. A.
,
Daniel
D. M.
,
Stone
M. L.
, and
Garfein
R. F.
,
1989
, “
Patellofemoral Problems After Anterior Cruciate Ligament Reconstruction
,”
Am. J. Sports Med.
, Vol.
17
, pp.
760
765
.
16.
Shelbourne
K. D.
,
Rubinstein
R. A.
,
VanMeter
C. D.
,
McCarroll
J. R.
, and
Rettig
A. C.
,
1994
, “
Correlation of Remaining Patellar Tendon Width With Quadriceps Strength After Autogenous Bone-Patellar Tendon-Bone Anterior Cruciate Ligament Reconstruction
,”
Am. J. Sports Med.
, Vol.
22
, pp.
774
778
.
17.
Tibone
J. E.
, and
Antich
T. J.
,
1988
, “
A Biomechanical Analysis of Anterior Cruciate Ligament Reconstruction With the Patellar Tendon
,”
Am. J. Sports Med.
, Vol.
16
, pp.
332
335
.
18.
Viidik
A.
,
1969
, “
Tensile Strength Properties of Achilles Tendon Systems in Trained and Untrained Rabbits
,”
Acta Orthop. Scand.
, Vol.
40
, pp.
261
272
.
19.
Wang, C. W., Weiss, J. A., Albright, J. P., Buckwalter, J. A., and Woo, S. L.-Y., 1989, “The Effects of Long Term Exercise on the Structural and Mechanical Properties of the Canine Medial Collateral Ligament,” in: 989 Biomechanics Symposium, Torzilli, P. A., and Friedman, M. H., eds., pp. 69–72, ASME, New York.
20.
Woo
S. L-Y.
,
Gomez
M. A.
,
Amiel
D.
,
Ritter
M. A.
,
Gelberman
R. H.
, and
Akeson
W. H.
,
1981
, “
The Effects of Exercise on the Biomechanical and Biochemical Properties of Swine Digital Flexor Tendons
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
103
, pp.
51
56
.
21.
Woo
S. L-Y.
,
Gomez
M. A.
,
Woo
Y. K.
, and
Akeson
W. H.
,
1982
, “
Mechanical Properties of Tendons and Ligaments. II. The Relationships of Immobilization and Exercise on Tissue Remodeling
,”
Biorheology
, Vol.
19
, pp.
397
408
.
22.
Yamamoto
N.
,
Hayashi
K.
,
Kuriyama
H.
,
Ohno
K.
,
Yasuda
K.
, and
Kaneda
K.
,
1992
a, “
Mechanical Properties of the Rabbit Patellar Tendon
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
114
, pp.
332
337
.
23.
Yamamoto
N.
,
Hayashi
K.
, and
Hayashi
F.
,
1992
b, “
In Vivo Measurement of Tension in the Rabbit Patellar Tendon
,”
Trans. Jap. Soc. Mech. Eng.
, Vol.
58
, pp.
1142
1147
.
24.
Yamamoto
N.
,
Ohno
K.
,
Hayashi
K.
,
Kuriyama
H.
,
Yasuda
K.
, and
Kaneda
K.
,
1993
, “
Effects of Stress Shielding on the Mechanical Properties of Rabbit Patellar Tendon
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
115
, pp.
23
28
.
25.
Yamamoto
N.
,
Hayashi
K.
,
Kuriyama
H.
,
Ohno
K.
,
Yasuda
K.
, and
Kaneda
K.
,
1996
, “
Effects of Restressing on the Mechanical Properties of Stress-Shielded Patellar Tendons in Rabbits
,”
ASME JOURNAL OF BIOMECHANICAL ENGINEERING
, Vol.
118
, pp.
216
220
.
26.
Zuckerman
J.
, and
Stull
G. A.
,
1969
, “
Effects of Exercise on Knee Ligament Separation Force in Rats
,”
J. Appl. Physiol.
, Vol.
26
, pp.
716
719
.
This content is only available via PDF.
You do not currently have access to this content.