Pulsed Electromagnetic Fields Reduce Postoperative Interleukin-1ß, Pain, and Inflammation: A Double-Blind, Placebo-Controlled Study in TRAM Flap Breast Reconstruction Patients.

BACKGROUND: Pulsed electromagnetic fields have been shown to reduce postoperative pain, inflammation, and narcotic requirements after breast reduction and augmentation surgical procedures. This study examined whether pulsed electromagnetic field therapy could produce similar results in patients undergoing unilateral transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction, a significantly more complex and painful surgical procedure. METHODS: In this double-blind, placebo-controlled, randomized study, 32 patients undergoing unilateral TRAM flap breast reconstruction received active or sham pulsed electromagnetic field therapy. Pain levels were measured by using a visual analogue scale; narcotic use and wound exudate volume were recorded starting 1 hour postoperatively. Wound exudates were analyzed for interleukin-1ß. RESULTS: Mean visual analogue scale pain scores were 2-fold higher in the sham cohort at 5 hours and 4-fold higher at 72 hours (p < 0.01), along with a concomitant 2-fold increase in narcotic use in sham patients (p < 0.01). Wound exudate volume was 2-fold higher in the sham cohort at 24 hours (p < 0.01), and mean interleukin-1ß concentration in wound exudates of sham patients was 5-fold higher at 24 hours (p < 0.001). CONCLUSIONS: Pulsed electromagnetic field therapy significantly reduced postoperative pain, inflammation, and narcotic use following TRAM flap breast reconstruction, paralleling its effect in breast reduction patients. Both studies also report a significant reduction of interleukin-1ß in the wound exudate, supporting a mechanism involving a pulsed electromagnetic field effect on nitric oxide/cyclic guanosine monophosphate signaling, which modulates the body's antiinflammatory pathways. Adjunctive pulsed electromagnetic field therapy could impact the speed and quality of wound repair in many surgical procedures. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, I.

Pulsed electromagnetic fields dosing impacts postoperative pain in breast reduction patients.

BACKGROUND: Pulsed electromagnetic fields (PEMF) reduce postoperative pain and narcotic requirements in breast augmentation, reduction, and reconstruction patients. PEMF enhances both calmodulin-dependent nitric oxide and/or cyclic guanosine monophosphate signaling and phosphodiesterase activity, which blocks cyclic guanosine monophosphate. The clinical effect of these competing responses on PEMF dosing is not known. METHODS: Two prospective, nonrandomized, active cohorts of breast reduction patients, with 15 min PEMF per 2 h; "Q2 (active)", and 5 min PEMF per 20 min; "5/20 (active)", dosing regimens were added to a previously reported double-blind clinical study wherein 20 min PEMF per 4 h, "Q4 (active)", dosing significantly accelerated postoperative pain reduction compared with Q4 shams. Postoperative visual analog scale pain scores and narcotic use were compared with results from the previous study. RESULTS: Visual analog scale scores at 24 h were 43% and 35% of pain at 1 h in the Q4 (active) and Q2 (active) cohorts, respectively (P < 0.01). Pain at 24 h in the 5/20 (active) cohort was 87% of pain at 1 h, compared with 74% in the Q4 (sham) cohort (P = 0.451). Concomitantly, narcotic usage in the 5/20 (active) and Q4 (sham) cohorts was not different (P = 0.478), and 2-fold higher than the Q4 (active) and Q2 (active) cohorts (P < 0.02). CONCLUSIONS: This prospective study shows Q4/Q2, but not 5/20 PEMF dosing, accelerated postoperative pain reduction compared with historical shams. The 5/20 (active) regimen increases NO 4-fold faster than the Q4 (active) regimen, possibly accelerating phosphodiesterase inhibition of cyclic guanosine monophosphate sufficiently to block the PEMF effect. This study helps define the dosing limits of clinically useful PEMF signals.

Nonthermal electromagnetic fields: from first messenger to therapeutic applications.

Nonthermal pulsed electromagnetic fields, from low frequency to pulse-modulated radio frequency, have been successfully employed as adjunctive therapy for the treatment of delayed and non-union fractures, fresh fractures and chronic wounds. Recent increased understanding of the mechanism of action of electromagnetic fields (EMF) has permitted technologic advances allowing the development of EMF devices which are portable and disposable, can be incorporated into dressings, supports and casts, and can be used over clothing. This broadens the use of non-pharmacological, non-invasive EMF therapy to the treatment of postoperative pain and edema to enhance surgical recovery. EMF therapy is rapidly becoming a standard part of surgical care, and new, more significant, clinical applications for osteoarthritis, brain and cardiac ischemia and traumatic brain injury are in the pipeline. This study reviews recent evidence which suggests that calmodulin (CaM)-dependent nitric oxide signaling is involved in cell and tissue response to weak nonthermal EMF signals. There is abundant evidence that EMF signals can be configured a priori to increase the rate of CaM activation, which, in turn, can modulate the biochemical cascades living cells and tissues employ in response to external insult. Successful applications in pilot clinical trials, coupled with evidence at the cellular and animal levels, provide support that EMF is a first messenger that can modulate the response of challenged biological systems.

Non-invasive electromagnetic field therapy produces rapid and substantial pain reduction in early knee osteoarthritis: a randomized double-blind pilot study.

This study examined whether a non-thermal, non-invasive, pulsed electromagnetic field (PEMF), known to modulate the calmodulin (CaM)-dependent nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) signaling pathway, could reduce pain in early knee OA. This randomized, placebo-controlled, double-blind pilot clinical study enrolled 34 patients. Patient selection required initial VAS ≥4, 2 h of standing activity per day, and no recent interventions such as cortisone injections or surgery. Results showed VAS pain score decreased in the active cohort by 50 ± 11% versus baseline starting at day 1 and persisting to day 42 (P < 0.001). There was no significant decrease in VAS versus baseline at any time point in the sham cohort (P = 0.227). The overall decrease in mean VAS score for the active cohort was nearly threefold that of the sham cohort (P < 0.001). The results suggest that non-thermal, non-invasive PEMF therapy can have a significant and rapid impact on pain from early knee OA and that larger clinical trials are warranted.

Attenuation of interleukin-1beta by pulsed electromagnetic fields after traumatic brain injury.

Traumatic Brain Injury (TBI) is a major cause of morbidity and mortality in civilian and military populations. Interleukin-1beta (IL-1ß) is a pro-inflammatory cytokine with a key role in the inflammatory response following TBI and studies indicate that attenuation of this cytokine improves behavioral outcomes. Pulsed electromagnetic fields (PEMF) can reduce inflammation after soft tissue injuries in animals and humans. Therefore, we explored whether PEMF signals could alter the course of IL-1ß production in rats subjected to closed-head contusive weight-drop injuries (Marmarou method) and penetrating needle-stick brain injuries. Protein levels, measured by the Biorad assay, were not altered by injuries or PEMF treatment. In addition, we verified that IL-1ß levels in cerebrospinal fluid (CSF) were proportional to injury severity in the contusion model. Results demonstrate that PEMF treatment attenuated IL-1ß levels up to 10-fold in CSF within 6h after contusive injury and also significantly suppressed IL-1ß within 17-24h after penetrating injury. In contrast, no differences in IL-1ß were seen between PEMF-treated and control groups in brain homogenates. To the authors' knowledge, this is the first report of the use of PEMF to modulate an inflammatory cytokine after TBI. These results warrant further studies to assess the effects of PEMF on other inflammatory markers and functional outcomes.

Effects of pulsed electromagnetic fields on interleukin-1 beta and postoperative pain: a double-blind, placebo-controlled, pilot study in breast reduction patients.

BACKGROUND: Surgeons seek new methods of pain control to reduce side effects and speed postoperative recovery. Pulsed electromagnetic fields are effective for bone and wound repair and pain and edema reduction. This study examined whether the effect of pulsed electromagnetic fields on postoperative pain was associated with differences in levels of cytokines and angiogenic factors in the wound bed. METHODS: In this double-blind, placebo-controlled, randomized study, 24 patients, undergoing breast reduction for symptomatic macromastia received pulsed electromagnetic field therapy configured to modulate the calmodulin-dependent nitric oxide signaling pathway. Pain levels were measured by a visual analogue scale, and narcotic use was recorded. Wound exudates were analyzed for interleukin (IL)-1 beta, tumor necrosis factor-alpha, vascular endothelial growth factor, and fibroblast growth factor-2. RESULTS: Pulsed electromagnetic fields produced a 57 percent decrease in mean pain scores at 1 hour (p < 0.01) and a 300 percent decrease at 5 hours (p < 0.001), persisting to 48 hours postoperatively in the active versus the control group, along with a concomitant 2.2-fold reduction in narcotic use in active patients (p = 0.002). Mean IL-1 beta concentration in the wound exudates of treated patients was 275 percent lower (p < 0.001). There were no significant differences found for tumor necrosis factor-alpha, vascular endothelial growth factor, or fibroblast growth factor-2 concentrations. CONCLUSIONS: Pulsed electromagnetic field therapy significantly reduced postoperative pain and narcotic use in the immediate postoperative period. The reduction of IL-1 beta in the wound exudate supports a mechanism that may involve manipulation of the dynamics of endogenous IL-1 beta in the wound bed by means of a pulsed electromagnetic field effect on nitric oxide signaling, which could impact the speed and quality of wound repair.

Evidence-based use of pulsed electromagnetic field therapy in clinical plastic surgery.

BACKGROUND: The initial development of pulsed electromagnetic field (PEMF) therapy and its evolution over the last century for use in clinical surgery has been slow, primarily because of lack of scientifically-derived, evidence-based knowledge of the mechanism of action. OBJECTIVE: Our objective was to review the major scientific breakthroughs and current understanding of the mechanism of action of PEMF therapy, providing clinicians with a sound basis for optimal use. METHODS: A literature review was conducted, including mechanism of action and biologic and clinical studies of PEMF. Using case illustrations, a holistic exposition on the clinical use of PEMF in plastic surgery was performed. RESULTS: PEMF therapy has been used successfully in the management of postsurgical pain and edema, the treatment of chronic wounds, and in facilitating vasodilatation and angiogenesis. Using scientific support, the authors present the currently accepted mechanism of action of PEMF therapy. CONCLUSIONS: This review shows that plastic surgeons have at hand a powerful tool with no known side effects for the adjunctive, noninvasive, nonpharmacologic management of postoperative pain and edema. Given the recent rapid advances in development of portable and economical PEMF devices, what has been of most significance to the plastic surgeon is the laboratory and clinical confirmation of decreased pain and swelling following injury or surgery.

Effects of pulsed electromagnetic fields on postoperative pain: a double-blind randomized pilot study in breast augmentation patients.

BACKGROUND: Postoperative pain may be experienced after breast augmentation surgery despite advances in surgical techniques which minimize trauma. The use of pharmacologic analgesics and narcotics may have undesirable side effects that can add to patient morbidity. This study reports the use of a portable and disposable noninvasive pulsed electromagnetic field (PEMF) device in a double-blind, randomized, placebo-controlled pilot study. This study was undertaken to determine if PEMF could provide pain control after breast augmentation. METHODS: Forty-two healthy females undergoing breast augmentation for aesthetic reasons entered the study. They were separated into three cohorts, one group (n = 14) received bilateral PEMF treatment, the second group (n = 14) received bilateral sham devices, and in the third group (n = 14) one of the breasts had an active device and the other a sham device. A total of 80 breasts were available for final analysis. Postoperative pain data were obtained using a visual analog scale (VAS) and pain recordings were obtained twice daily through postoperative day (POD) 7. Postoperative analgesic medication use was also followed. RESULTS: VAS data showed that pain had decreased in the active cohort by nearly a factor of three times that for the sham cohort by POD 3 (p < 0.001), and persisted at this level to POD 7. Patient use of postoperative pain medication correspondingly also decreased nearly three times faster in the active versus the sham cohorts by POD 3 (p < 0.001). CONCLUSION: Pulsed electromagnetic field therapy, adjunctive to standard of care, can provide pain control with a noninvasive modality and reduce morbidity due to pain medication after breast augmentation surgery.

Low intensity permanent magnets in the treatment of chronic lumbar radicular pain.

We assessed the pain-relieving efficacy of static magnetic fields produced by 200 Gauss (G) magnets compared with 50G magnets in a double-blind, randomized, two-phase crossover study in patients with chronic lumbar radicular pain. The surface field strengths of the magnets were 200 and 50G. Phase I included four random periods of two-week duration: two periods with 200G, one period with 50G, and one period of "no treatment." The magnets were positioned either vertically or horizontally in standard lumbosacral elastic corsets. Phase II consisted of two five-week periods with the most effective magnet from Phase I and its corresponding 50 or 200G device. The primary outcome was average daily leg pain score (0-10 scale) in each period of Phase II. Thirty-eight of 40 randomized patients completed Phase I, and 28 of 31 Phase II participants completed the study. In Phase I, pain scores did not differ significantly between 200 and 50G magnets. Phase II average leg pain scores tended to be lower with 200 vs. 50G magnets (3.2+/-2.1 for 200G vs. 3.9+/-2.2 for 50G magnets [P=0.08]) after excluding one unblinded patient. The relative treatment effect of the 200G magnets appeared to increase throughout the five-week period. Although these data cannot rule out a chance effect, the positive trends suggest that larger, longer-duration, sham-controlled trials with 200G magnets be considered in patients with chronic lumbar radicular pain.

Pulsed magnetic field therapy increases tensile strength in a rat Achilles' tendon repair model.

PURPOSE: To examine the effect of pulsing electromagnetic fields on the biomechanic strength of rat Achilles' tendons at 3 weeks after transection and repair. METHODS: This noninvasive modality was tested in a prospective, randomized, double-blinded, placebo-controlled study to evaluate the effect of a specific noninvasive radiofrequency pulsed electromagnetic field signal on tendon tensile strength at 21 days post transection in a rat model. RESULTS: In the animals receiving PMF exposure, an increase in tensile strength of up to 69% was noted at the repair site of the rat Achilles' tendon at 3 weeks after transection and repair compared with nonstimulated control animals. CONCLUSIONS: The application of electromagnetic fields, configured to enhance Ca(2+) binding in the growth factor cascades involved in tissue healing, achieved a marked increase of tensile strength at the repair site in this animal model. If similar effects occur in humans, rehabilitation could begin earlier and the risk of developing adhesions or rupturing the tendon in the early postoperative period could be reduced.

Efficacy of static magnetic field therapy in chronic pelvic pain: a double-blind pilot study.

OBJECTIVE: The aim of the study was to determine the efficacy of static magnetic field therapy for the treatment of chronic pelvic pain (CPP) by measuring changes in pain relief and disability. STUDY DESIGN: Thirty-two patients with CPP completed 2 weeks and 19 patients completed 4 weeks of randomized double-blind placebo-controlled treatment at a gynecology clinic. Active (500 G) or placebo magnets were applied to abdominal trigger points for 24 hour per day. The McGill Pain Questionnaire, Pain Disability Index, and Clinical Global Impressions Scale were outcome measures. RESULTS: Patients receiving active magnets who completed 4 weeks of double-blind treatment had significantly lower Pain Disability Index (P <.05), Clinical Global Impressions-Severity (P <.05), and Clinical Global Impressions-Improvement (P <.01) scores than those receiving placebo magnets, but were more likely to correctly identify their treatment (P <.05). CONCLUSION: SMF therapy significantly improves disability and may reduce pain when active magnets are worn continuously for 4 weeks in patients with CPP, but blinding efficacy is compromised.