Article Text

PDF

Pulsed electromagnetic field therapy in the management of knee OA
  1. K PFEIFFER
  1. Augsburgerstr 4
  2. 80337 München
  3. Germany
    1. M DOUGADOS
    1. Clinique de Rhumatologie B
    2. Groupe Hospitalier Cochin
    3. 27 rue du Fauborg St Jacques
    4. 75679 Paris CEDEX 14
    5. France
    6. Rheumatology Unit
    7. City Hospital, Nottingham NG5 1PB, UK
      1. M DOHERTY
      1. Clinique de Rhumatologie B
      2. Groupe Hospitalier Cochin
      3. 27 rue du Fauborg St Jacques
      4. 75679 Paris CEDEX 14
      5. France
      6. Rheumatology Unit
      7. City Hospital, Nottingham NG5 1PB, UK

        Statistics from Altmetric.com

        It seems most unusual that in a review of “all currently available treatments” for knee osteoarthritis (OA) by 21 authorities and “two experts in the field of guidelines methodology”, pulsed electromagnetic field therapy was not mentioned in the text or the 51 references.1 This is particularly troubling because over 2800 publications between 1966 and 1998 were retrieved. An identical search for efficacy of magnetic field therapy during this period listed 31 studies with at least one control group,2 including two double blind trials citing benefits in knee OA from a peer reviewed arthritis journal.3 4 In 1999 over 50 000 patients received pulsed signal therapy (PST) prescribed by over 1000 doctors at more than 300 clinics and hospitals in 16 countries, where it is usually reimbursed by fiscal intermediaries because of its proven record of cost effectiveness and safety. A summary of PST double blind and randomised study results in over 50 000 patients has been published,5 and findings in 100 000 patients (the vast majority with knee OA) have also been reported at recent international conferences.6 7 Although “alternative” remedies, ranging from minerals, vitamins, nutritional supplements, and capsaicin and diclofenac gels to sex hormones were discussed, in contrast with PST, none satisfied the category criteria the panel established to determine strong recommendation. Nor do any have the solid basic science studies that PST provides with its in vitro support for mechanisms of action to explain efficacy based on proteoglycan synthesis and chondrocyte stimulation results.8 9

        Pulsed signal therapy is the result of three decades of research designed to characterise the piezoelectric signal that normally stimulates chondrocyte activity by creating a streaming potential in the extracellular matrix when bone is subjected to pressure. Although the transmission of this signal is impaired in OA, PST can reproduce this streaming potential in affected joints under no load, and the nine one-hour daily non-invasive treatments are devoid of any adverse side effects. Long term follow up confirms sustained pain relief, improved mobility, and a high safety profile as assessed by validated instruments (WOMAC, OMERAC, modified Ritchie scales) as well as evaluations by doctors and patients.

        My interest in PST began in 1995 when a Journal of Rheumatology article suggested that it might alleviate my 15 year old daughter's pain caused by an arthritic condition. Although unable to walk without crutches, two weeks after a course of PST her pain was relieved and she could walk unassisted. A month later she was able to pursue all athletic activities without discomfort. She subsequently enrolled in a martial arts class, recently attained black belt status, and has continued to remain symptom free without the need for any drugs or further treatment for the past five years.

        Although I am certified in cardiology and gastroenterology, a significant portion of my practice is now devoted to exploring how PST achieves its benefits.10 I have treated 1000 patients, most of whom had knee OA, with very gratifying results similar to those reported in the literature. The panel cited two prior efforts to establish guidelines for treating knee OA, emphasising that these “primarily represent consensus statements from expert panels” and “The type and strength of evidence to support such guidelines remain unclear.” Their stated objective, therefore, was to “develop guidelines relating to clinical issues in OA management, and to indicate clearly the level of evidence to support individual statements”. However, electromagnetic therapy approaches were again omitted, though at least one of the members is quite familiar with PST. The reason for this exclusion is not clear and I believe that your readership deserves to be aware of this extremely safe and effective option.

        References

        Authors' reply

        We thank Dr Pfeiffer for raising this point. The EULAR recommendations for the management of knee osteoarthritis1-1combined an evidence based approach and a consensus approach. The evidence based approach—that is, the literature research, was only applied for the treatment modalities selected by the experts at the first meeting of the committee (see table 1 of the paper).

        Pulsed electromagnetic field therapy, with other less commonly used interventions, was not included in this list, and its evidence for efficacy was therefore not assessed. However, as emphasised by Dr Pfeiffer, an evidence based evaluation of all other interventions would be of interest and could be considered for inclusion in the next round of evidence based guidelines.

        References

        1. 1-1.
        View Abstract

        Request permissions

        If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.