SLR - June 2012 - Lauren Kishman
Reference: Brook, J., Dauphinee, D.M., Korpinen, J., & Rawe, I.M. (2012). Pulsed Radiofrequency Electromagnetic Field Therapy: A Potential Novel Treatment of Plantar Fasciitis. Journal of Foot and Ankle Surgery, 51, 312-316
Scientific Literature Review
Reviewed by: Lauren Kishman, DPM
Residency Program: Cleveland Clinic Foundation/Kaiser Permanente
Podiatric Relevance:
Plantar fasciitis is the most common cause of heel pain with an estimated one million office visits per year involving the diagnosis and treatment of plantar fasciitis. Treatments are most commonly conservative in nature, but can take up to two years to achieve resolution. This study investigates the efficacy of pulsed radiofrequency electromagnetic field (PRFE) therapy as an adjunct to conservative treatment for plantar fasciitis.
Methods:
A multicenter, prospective, randomized, double-blind, placebo and positive control trial was performed on 70 patients with diagnosed plantar fasciitis. The primary diagnostic criterion was pain at the insertion of the plantar fascia into the calcaneus, plantar medially or plantarly. Exclusion criteria included any osseous cause of heel pain, including stress fracture or bone tumor, pain directly plantar to calcaneal tuber and neuritis. Based on random selection of previously coded PRFE device, patients were randomized to therapeutic and placebo groups. The ActiPatch device with carrier frequency of 27.12 MHz, 1000 pulses/second was utilized in this study. The placebo device appeared identical to the therapeutic device but did not emit a radiofrequency electromagnetic field. Forty-eight patients were included in the therapeutic group, with 28 patients in the placebo group. The device was worn nightly for seven consecutive days with the antenna of the device placed directly over the site of heel pain. Morning and evening pain scores were reported by the patient using a 10-point visual analog scale (VAS). Daily analgesic medication use was also recorded by the patient.
Results:
All patients completed the study. No adverse events were reported and the PRFE therapy devices were well tolerated in all patients. There was no significant difference between the study groups demographics or VAS scores at day one of therapy. A decrease in both morning and evening VAS scores was noted in placebo and therapeutic groups at the end of therapy. Although morning VAS pain scores for the placebo group did show a 7.9 percent decline, no significant change was noted at trial completion. Morning VAS scores in the therapeutic group were found to decline 40 percent throughout the study period with a significant difference in morning VAS pain rating noted at days four through seven of treatment. Linear regression analysis also showed significantly different rates of improvement between groups. A 19 percent pain decline in the placebo group and 30 percent pain decline in the therapeutic group were observed in the evening VAS pain rating, though these results were not found to be significant. No significant difference in rate of decline was noted between groups. Evening VAS pain rating at days four through seven was significantly improved from initial report in the therapeutic group. Total pill and average medication usage showed a downward trend in therapeutic group that was not seen in the placebo group, however these results were not found to be significant.
Conclusions:
Overnight wear of the PRFE device shows promise as a conservative treatment option for plantar fasciitis. This is the first study into the investigation of the PRFE device as an outpatient adjunctive therapy. The current study results support its use as an effective modality in decreasing morning pain in patients suffering from plantar fasciitis. Benefits to therapy include ease of use, being drug free, noninvasive and no reported side effects. Limitations to this study include short length of data collection and lack of long-term follow-up. Additional studies in this area are needed to confirm these results as well as determine long-term effects of treatment.