The relationship between electrical stimulus and viscoelastic parameters of the denervated anterior thigh muscles
- Resource Type
- Conference
- Authors
- Krenn, M.; Rafolt, D.; Gallasch, E.; Kern, H.; Mayr, W.
- Source
- 2009 ICME International Conference on Complex Medical Engineering Complex Medical Engineering, 2009. CME. ICME International Conference on. :1-5 Apr, 2009
- Subject
- Bioengineering
Computing and Processing
Signal Processing and Analysis
Viscosity
Elasticity
Thigh
Muscles
Knee
Neuromuscular stimulation
Leg
System testing
Electrical stimulation
Gravity
- Language
As a part of the EU-project “RISE” a pendulum test was applied to evaluate the effect of functional electrical stimulation (FES) on denervated degenerated anterior thigh muscles. A sensor-actuator system was connected to the lower leg via an adjustable lever to hold the subject's knee joint align with the pivot of the test device. The motor of the pendulum system allowed to compensate static torques due to electrical stimulation and gravity. The tests were performed at two initial positions (knee angle of 90° and 120°). First passive measurements were taken and secondly FES was applied up to ±60V. A second-order dynamical model was applied to extract stiffness and viscous parameters from the recorded damped oscillation. The pendulum test was proved a sensitive method to detect even weak contractile capacity of long-term denervated and degenerated muscles. Therefore, the pendulum test is a useful clinical tool to assess muscle performance in denervated paraplegics.