Ankle joint stiffness during phases of human walking.

Student thesis: Master thesis (including HD thesis)

  • Piotr Plocharski
  • Maciej Plocharski
Understanding the biomechanics of human ankle
joint in dynamic conditions allows insight into design
of ankle prostheses which could theoretically
provide a functionality similar to that of a healthy
limb. Joint stiffness is one of the factors that characterises
the mechanical properties of a joint, as it
relates the dynamic relationship between joint position
and the torque acting about it.
11 young non-disabled subjects (24-27 years) participated
in the study. Subjects walked on a
treadmill while perturbations (single displacement
pulses) were applied to the ankle and the resulting
torque was measured. Ankle joint stiffness
was investigated during walking conditions in three
phases of gait cycle, and in standing conditions,
where subjects’ leg postures isometrically matched
the different phases of the dynamic trials. Stiffness
estimates were generated using amulti-segment algorithm,
with position and torque used to characterise
the dynamic system non–parametrically.
Results showed a non–significant difference between
the mean values of joint stiffness during dynamic
and isometric trials, and a statistically significant
difference in mean ankle stiffness was found
between the three phases of gait cycle at plantarflexion
[P < 0.0005].
Publication date4 Jun 2013
Number of pages90
ID: 77235746