Computer modelling of magnetotherapy in orthopedic treatments

The paper aims to clarify the method/methodology of establishing a computer model of the electromagnetic therapy connected with some knee joint problems. Two cases are considered: the arthritis of the knee and the fracture of bone. In both cases the analysis of eddy current distribution in the knee is made. It gives results which can be helpful in the planning of treatment. The paper presents the exemplary results of eddy current distribution inside a bone. A short discussion on the safety aspect of magnetotherapy has been carried out.

In order to calculate the eddy current distribution in human knee joint the low frequency finite‐difference time‐domain algorithm has been applied. The numerical model of the leg was based on US Air Force Research Laboratory data and the electrical properties of tissues were modeled using 4‐Cole‐Cole approximation with parameters taken from Gabriels.

The paper presents the general methodology which can be used in magnetotherapy to estimate a magnetic flux density of stimulators and value of current density inside the knee joint. Both factors mentioned above can be helpful in therapeutical processes, i.e. in magnetoteraphy.

The eddy current distribution is limited to the presented model and it is obvious it can be different for another one as it is shown in the paper but it is also shown that the biggest value of eddy current density is just in the vicinity of the joint, so it can help in a therapeutical process.

The methodology of estimating the values of current density and magnetic flux density can be used by physiologists and doctors to determine the value of current density which gives therapeutical effect.

The efficient application of low frequency finite‐difference time‐domain algorithm to the electromagnetic therapy connected with some knee joint problems has been shown and the general methodology has been conducted.