This paper presents the results of studies on the effects of suppression of chronic pain by currents with low (TENS), medium (Intf) and high (MT) frequencies, in dogs with ankylosing spondilytis. Prior to imaging diagnostics the dogs were clinically observed, trias was estimated, as well as habitus, neurological signs and degree of pain. After a 10 day treatment it was clear that all three treatments resulted in a significant decrease of pain at rest, during activity or during palpation. TENS currents have shown the highest degree of effect. All treated animals have shown improved motility after a few months of therapy. Despite the fact that all animals had an improved clinical picture none of the applied currents resulted in a complete loss of limping. Dogs treated with Intf currents displayed a decrease in muscular atrophy. Motility of the coxofemoural joint was most evident in the group treated with microwaves