This study examined the effects of Pulsed Electromagnetic Fields (PEMF) therapy on the expression of c-fos protein in rats with knee osteoarthritis (OA). The aim of this study was to compare the improvement of pain
relief in two experimental groups: PEMF and treadmill exercise. Thirty-two male Sprague-Dawley rats were randomly divided into four groups with eight rats in each: CON1 (including rats sacrificed 1 day after OA
induction), CON7 (including rat sacrificed 7 days after OA induction), PEMF (including rats with applied PEMF for 7 days after OA induction), TE (including rats with applied treadmill exercise for 7 days after OA
induction). A statistically significant reduction on expression of c-fos was observed in TE and PEMF groups compared to that in CON7 group. However, there was no significant difference in expression of c-fos between
the TE group and PEMF group. It is suggested that PEMF could have positive effect on pain relief for OA confirming reduction on expression of c-fos in the spinal cord.