Microcontroller based non invasive diagnosis of knee joint diseases

This paper deals with the monitoring of joint diseases status under the influence of high frequency electrical signals. The response of the system for applied electrical signal was acquired, processed and displayed using four surface electrodes, Bio signal amplifier, Analogue to digital converter and PIC microcontroller. The electrical property of the tissue alters whenever the tissue surface is applied with any external electrical energy at very high frequency in the range of kHz. These electrical conductivity changes vary with healthy joint and disease affected joints. On the basis of changes in the electrical conductivity changes under the existence of high frequency signal a non invasive system has been implemented to monitor the disease status. The conductivity changes were monitored in terms of voltage drop across the joint region. Based on the voltage value varying from IV to 3V and its corresponding impedance value joint diseases were diagnosed. During the proposed research microcontroller was utilized for processing and displaying real time voltage signal acquired from knee joint surface using metal surface electrodes. These displayed real time voltage values were stored in local PC using microcontroller and MAX-232 IC for serial communication.