Effect of interferential current of different amplitude-modulated frequencies, on threshold and number of accommodations on healthy painless individuals

BACKGROUND AND OBJECTIVES:Despite the widespread use of interferential current, controversy exists in the literature on the optimal stimulation parameters. The aim of this study was to evaluate the threshold and the total number of accommodations in subjects stimulated by different amplitude-modulated frequencies.METHODS:The study is a clinical, cross-over trial with randomized and blinded convenience sample consisted of 20 healthy subjects, with mean age of 20.35 years, of both genders. Volunteers underwent interferential current for 20 minutes, the bipolar form, with electrodes placed on the elbow joint being positioned one above the superficiality of the ulnar nerve and the other of the median nerve. Equipment parameters were: base frequency of 4,000Hz, amplitude-modulated frequencies 1, 10 or 100Hz (according to the subgroup). Threshold and total number of accommodations were assessed.RESULTS:For the accommodation threshold no significant differences were found (p>0.05). With regard to the number of accommodations, there have been significant differences between the frequencies of 10 and 100Hz (p<0.05).CONCLUSION:There was no significant difference in the accommodation threshold; however, we observed significant differences between the frequencies of 10 and 100Hz.