Assessment of knee osteoarthritis by bioelectrical impedance

This study aimed to investigate the application of a bioimpedance spectroscopy technique, based on the current response to a voltage step excitation, as a diagnosis tool to the knee osteoarthritis problem. Up to now, 14 individuals (4 men and 10 women) have participated of the study, being grouped as health subjects (NG) and subjects with knee osteoarthritis diagnosis (OG). A total of 28 bioelectrical impedance measurements in the knee joint have been made. The average value of the knee intracellular resistance was of 281 82.6 Q in the NG and 143/spl plusmn/33.9 Q in the OG. Besides this difference is statistically significant (p<0.01) between the groups, ratio between the intracellular and extracellular resistances, that was of the 1.6/spl plusmn/0.5 in the NG and 0.8/spl plusmn/0.2 in the OG, seems to be a better index to be used in the diagnosis. The results of this study suggest that the proposed method of bioelectrical impedance evaluation, when applied the diagnosis of the knee, is a valid method to determine the inflammatory pathological conditions of this joint.