Objective—To develop and validate a novel instrumented
treadmill capable of determining vertical ground reaction forces of all 4 limbs simultaneously in
Sample Population—Data obtained while a horse
was walking and trotting on the treadmill.
Procedure—18 piezo-electric force transducers
were mounted between the treadmill frame and
supporting steel platform to measure the actual
forces at the corresponding bearing points. Each of
the 18 sensor forces is equal to the sum of the
unknown hoof forces weighted with the transfer
coefficients of the corresponding force application
points. The 4 force traces were calculated, solving at
each time point the resulting equation system, using
the Gaussian least-squares method. System validation
comprised the following tests: determination of
the survey accuracy of the positioning system,
determination of the natural frequencies of the system,
linearity test of the force transfer to the individual
sensors, determination of superimposed
forces with the treadmill-integrated force measuring
system (TiF) in a static configuration, and comparison
of vertical ground reaction forces determined
simultaneously by use of TiF and force shoes mounted
on the forelimbs of a horse.
Results—Comparison between static test loads and
TiF-calculated forces revealed deviations of < 1.4%. Force traces of TiF-calculated values and those recorded
by use of the force shoes were highly correlated ( r ≥ 0.998).
Conclusions and Clinical Relevance—This instrumented
treadmill allows a reliable assessment of load distribution and interlimb coordination in a short period
and, therefore, is suitable for use in experimental and clinical investigations. (Am J Vet Res 002;63:520–527).