The state of tissue
hydration determines
the strain rate sensitive stiffness
of human patellar tendon.
J. Biomechanics. 30(1):79-81, 1997
Haut, TL, Haut,RC.
The purpose of this study
was to investigate the effect of tissue hydration on the structural properties
of human patellar tendon under a low (0.5%/s) and a high (50%/s) strain
rate. Patella-tendon-tibia complexes
were bisected into medial and lateral halves and immersed in distilled water,
while the contralateral medial and lateral halves were immersed in a 25%
sucrose solution. Specimens were
subjected to a load relaxation experiment prior to being stretched to failure.
The experiments indicated that tendons relaxed faster in hypotonic versus hypertonic
solutions. At the strain rate of 50%/s, the structural stiffness was
significantly higher for the tendons immersed in a hypotonic solution versus in a hypertonic solution. No differences in tensile stiffness were
documented in various baths at the strain rate of 0.5%/s. Tendons immersed in
the hypotonic solution were also significantly stiffer for a strain rate
of 50%/s than 0.5%/s. The results indicate that the structural
properties of human patellar tendon are more sensitive to time when the tissues
are fully hydrated. This study suggests
human patellar tendons are biphasic materials and future studies are needed to
document their intrinsic mechanical properties.
Orthopaedic
Biomechanics Laboratories,
College of Osteopathic Medicine,
Michigan State University,
East Lansing, Michigan 48824
Please
address correspondence to:
Roger C.
Haut, Ph.D.,
Orthopaedic Biomechanics Laboratory,
College of Osteopathic Medicine,
A414 East Fee Hall,
Michigan State University,
East Lansing, MI 48824,
Tel: (517)355-0320,
Fax:
(517)353-0789,
E-mail:
haut@msu.edu