Objective: To determine if the chronic pain frequently presented by postpolio patients can be relieved by application of magnetic fields applied directly over an identified pain trigger point.
Design: Double-blind randomized clinical trial.
Setting: The postpolio clinic of a large rehabilitation hospital.
Patients: Fifty patients with diagnosed postpolio syndrome who reported muscular or arthritic-like pain.
Intervention: Application of active or placebo 300 to 500 Gauss magnetic devices to the affected area for 45 minutes.
Main outcome measure: Score on the McGill Pain Questionnaire.
Results: Patients who received the active device experienced an average pain score decrease of 4.4 +/- 3.1 (p < .0001) on a 10-point scale. Those with the placebo devices experienced a decrease of 1.1 +/- 1.6 points (p < .005). The proportion of patients in the active-device group who reported a pain score decrease greater than the average placebo effect was 76%, compared with 19% in the placebo-device group (p < .0001).
Conclusions: The application of a device delivering static magnetic fields of 300 to 500 Gauss over a pain trigger point results in significant and prompt relief of pain in postpolio subjects.