Finite element analysis of electrical impedance myography in the rat hind limb.

Electrical impedance myography (EIM) is a form of muscle assessment based on the surface application of electrical current and measurement of the resulting voltages over a muscle group of interest. In order to better understand the effect of pathological change in muscle, EIM has recently been applied to the rat. In this study, a finite element model of EIM is presented for the rat hind limb which incorporates the detailed anatomy of the leg based on computerized tomographic imaging and conductivity and permittivity values obtained from the rat gastrocnemius muscle. In addition, the angular anisotropy of the biceps femoris muscle has been included. The model successfully predicts the recorded surface impedances measured with EIM.