A PROSPECTIVE, RANDOMIZED, PLACEBO CONTROLLED, DOUBLE-

0022-5347/05/1736-2044/0
THE JOURNAL OF UROLOGY®
Copyright © 2005 by AMERICAN UROLOGICAL ASSOCIATION
Vol. 173, 2044 –2047, June 2005
Printed in U.S.A.
DOI: 10.1097/01.ju.0000158445.68149.38
A PROSPECTIVE, RANDOMIZED, PLACEBO CONTROLLED, DOUBLEBLIND STUDY OF PELVIC ELECTROMAGNETIC THERAPY FOR THE
TREATMENT OF CHRONIC PELVIC PAIN SYNDROME WITH 1 YEAR OF
FOLLOWUP
E. ROWE, C. SMITH, L. LAVERICK, J. ELKABIR, R. O’N WITHEROW
AND
A. PATEL
From the Department of Urology, St. Mary’s Hospital, London, United Kingdom
ABSTRACT
Purpose: Male chronic pelvic pain syndrome is a condition of uncertain etiology and treatment
is often unsatisfactory. There is evidence that the symptom complex may result from pelvic floor
muscular dysfunction and/or neural hypersensitivity/inflammation. We hypothesized that the
application of electromagnetic therapy may have a neuromodulating effect on pelvic floor spasm
and neural hypersensitivity.
Materials and Methods: Following full Stamey localization men with National Institute of
Diabetes and Digestive and Kidney Diseases category III prostatitis were prospectively randomized to receive active electromagnetic or placebo therapy. Active therapy consisted of 15 minutes
of pelvic floor stimulation at a frequency of 10 Hz, followed by a further 15 minutes at 50 Hz,
twice weekly for 4 weeks. Patients were evaluated at baseline, 3 months and 1 year after
treatment using validated visual analog scores.
Results: A total of 21 men with a mean age of 47.8 years (range 25 to 67) were analyzed. Mean
symptom scores decreased significantly in the actively treated group at 3 months and 1 year
(p ⬍0.05), unlike the placebo group, which showed no significant change (p ⬎0.05). Subanalysis
of those receiving active treatment showed that the greatest improvement was in pain related
symptoms.
Conclusions: The novel use of pelvic floor electromagnetic therapy may be a promising new
noninvasive option for chronic pelvic pain syndrome in men.
KEY WORDS: pelvic pain, electromagnetics, prostate, pain, prostatitis
The uncertain etiology and variable response to treatment
has made prostatitis a challenging entity. In a national survey of physician visits in the United States a diagnosis of
prostatitis was made in 8% of urological and 1% of primary
care physician visits, respectively.1 This confirmed it as a
significant health problem, supporting previous estimates of
approximately 2 million prostatitis related outpatient visits
yearly nationwide.2 Globally the reported incidence of
prostatitis-like symptoms has been shown to be 2.7% in the
Far East to 14.2% in Northern Europe.3, 4 In 1995 the National Institutes of Health-National Institute of Diabetes and
Digestive and Kidney Diseases (NIDDK) workshop reached a
consensus on the definition and classification of prostatitis
syndromes.5 This has formed the basis for subsequent research on the pathophysiology of the disease and the efficacy
of therapeutic measures.
The commonest and yet most poorly understood of these
prostatitis syndromes is category III or chronic pelvic pain
syndrome (CPPS). It has been shown that, while men with
CPPS have significantly higher leukocyte counts in urine and
expressed prostatic secretions compared with age matched
controls, inflammation and infection do not necessarily correlate with symptom severity.6, 7 The lack of a direct relationship between inflammation and symptoms is supported
through studies of prostate histopathology, in which moderate or severe inflammation was identified in only 5% of men
with CPPS.8
Contributory factors in the pathophysiology of CPPS may
include obstruction to bladder emptying. Symptomatic relief
has been demonstrated with the use of ␣-blocking pharmaSubmitted for publication July 19, 2004.
cotherapy, particularly with regard to decreasing pain.9
Therefore muscle tone in the urethra/sphincter mechanism
may contribute to the pain experienced by men with CPPS.
Despite these findings the pathophysiology remains elusive
and the role of neurogenic inflammation may offer a possible
explanation. It results from a complex interaction between the
central/peripheral nervous system and the immune system,
causing the release of neuromediators that activate receptors
on specific cells, including mast cells, Langerhans’ cells, microvascular endothelial cells, fibroblasts and infiltrating immune
cells. The concept of neurogenic inflammation and its effect on
mast cell function, vasoregulation and leukocyte recruitment in
the pathophysiology of CPPS represents a new and interesting
avenue for further research.10, 11 Also, the role of purinergic
signaling through the release of urothelial adenosine triphosphate and the stimulation of subepithelial nerve plexus via the
purinergic P2X3 receptor, resulting in pain, may provide an
explanation for the symptom profile seen in CPPS.12
Conventional treatment has focused on long, empirical
courses of expensive broad-spectrum antibiotics, mostly of
the quinolone class, with or without the concomitant use of
an ␣-blocker and anti-inflammatory agents. Stepwise introduction of these therapies has also been shown to be of
benefit.13 There is also emerging evidence of the benefits of
finasteride in the management of CPPS.14
At the turn of the 19th century stimulation with electrical
current and changing magnetic fields was used to treat surface conditions associated with intractable pain, such as
painful malignant ulcers. The analgesic benefits of pulsed
electromagnetic fields for relieving pelvic pain has been investigated in women with tissue trauma and chronic refractory pelvic pain.15, 16 However, in the application of electro-
2044
ELECTROMAGNETIC THERAPY FOR MALE CHRONIC PELVIC PAIN SYNDROME
2045
magnetic stimulation to the pelvis most research has been in
the management of female stress and urge incontinence.
Despite its uncertain etiology there is some evidence that
the symptom complex found in CPPS may be founded at least
in part in pelvic floor muscular dysfunction and/or neurogenic hypersensitivity/inflammation. We hypothesized that
the application of a rapidly changing electromagnetic field
applied noninvasively to the perineum of the subject may
result in neural excitation and pelvic floor muscle stimulation to a degree that breaks the cycle of tonic muscular spasm
and neural hypersensitivity/inflammation, thereby, restoring
more normal pelvic floor muscular activity.
MATERIALS AND METHODS
A total of 21 men attending the urology outpatient clinic
with a diagnosis of NIDDK category IIIA or IIIB prostatitis
syndrome were invited to take part in a trial of electromagnetic pelvic floor therapy. Entry criteria were age 70 years or
less and a full Stamey procedure to exclude urinary microorganisms. Prostate cancer had been excluded by normal serum prostate specific antigen, clinically benign digital rectal
examination or negative previous biopsy. Patients with previous pelvic radiotherapy were also excluded.
Each man had previously undergone several types of failed
medical therapy for the condition, which typically included
multiple antibiotic courses, ␣-blockers and occasionally antidepressants. After obtaining informed consent eligible subjects were randomized to active and placebo groups using
computer generated, blocked randomization numbers. Patients were informed about the nature of the treatment, the
treatment schedule and the possibility that they might be
randomized to placebo but they were not given a detailed
description of what local pelvic sensations, if any, to expect
during treatment, so as not to bias blinding.
All men were asked to complete a baseline symptom visual
analog score (VAS) questionnaire that included 5 items of
pain related questions and 4 covering urinary symptoms (see
Appendix). The VAS questionnaire was adopted from the
validated symptom severity index designed by Nickel and
Sorensen.17 The question regarding painful digital rectal examination was omitted because the questionnaire was
mailed and, hence, clinical evaluation was not possible. Each
individual question was scored from 0 —asymptomatic to
10 —severely symptomatic, providing a total score of 0 to 90.
The symptom score questionnaire was re-administered 3
months and again 1 year following treatment in a doubleblind manner with patients and the individual analyzing the
data blinded to the identity of those who had received active
treatment.
The active treatment regime was empirical and consisted
of 2 sessions weekly for 4 weeks (total 8 sessions). During
each half-hour session the patient would sit centrally on the
Neotonus™ electromagnetic chair for 2 consecutive 15minute periods (fig. 1). The frequency was set low at 10 Hz for
the first 15-minute period and increased to 50 Hz for the
second 15-minute period. The gain was set low initially and
gradually increased, as tolerated by the patient. Patients
who received placebo were treated in a manner identical to
that in the active treatment group in all respects except no
active stimulation was applied from the device. Instead, the
chair was switched on so that the fan could be heard and a
hidden speaker under the stimulation device replicated the
sounds created during active treatment. Men receiving active
and placebo therapy were treated on alternate days to prevent cross-talk between groups, which may have compromised study blinding. Statistical analysis was performed using Student’s t test.
FIG. 1. Neotonus™ electromagnetic chair. Reproduced with permission from Neotonus™.
RESULTS
A total of 21 men with a mean age of 47.8 years (range 25
to 67) were entered into the study. Of the 21 men 11 were
randomized to the active treatment group and 10 were randomized to the placebo treatment group. Four men failed to
complete the 4-week treatment, including 1 in the active
treatment group and 3 in the placebo group. They were
excluded from further analysis. Followup data were obtained
on 17 men at 3 months (10 in the active and 7 in the placebo
group) and 13 at 1 year (8 and 5, respectively).
A significant difference was observed when mean symptom
scores in the active and placebo groups were analyzed. There
was a statistically significant decrease in mean symptom scores
in the active treatment arm from 38.8 of 90 at baseline to 26.4
of 90 at 3 months (95% CI 0.9 to 21.9, p ⬍0.05) and to 24.0 of 90
at 1 year (95% CI 0.15 to 30.85, p ⬍0.05). There was no statistically significant change in symptom scores in the placebo
group, which remained relatively unchanged at mean of 39.3
of 90 at baseline, 42.4 of 90 at 3 months (95% CI ⫺1.7 to 22.37,
p ⬎0.05) and 33.6 of 90 at 1 year (95% CI ⫺32.66 to 28.26,
p ⬎0.05, fig. 2).
On differential analysis separating pain scores from urination scores similar improvement was seen in the active treatment group. The pain score decreased significantly in those
receiving active treatment from a mean baseline of 21.7 of 50
to 14.7 of 50 at 3 months (95% CI 3.57 to 12.43, p ⬍0.05) and
to 11.9 of 50 at 1 year (95% CI 2.8 to 18.7, p ⬍0.05). The mean
pain score in the placebo group remained relatively unchanged for the same periods, that is 21.1 of 50 at baseline,
22.4 of 50 at 3 months (95% CI ⫺16.38 to 13.8, p ⬎0.05) and
18 of 50 at 1 year (95% CI ⫺22.6 to 19.8, p ⬎0.05, fig. 3).
Mean urinary symptom scores showed a significant decrease from 17.1 of 40 at baseline to 11.7 of 40 at 3 months in
those receiving active treatment (95% CI 1.2 to 12.4,
p ⬍0.05). While mean urinary symptom scores remained
below baseline at the 1-year followup, improvement in the
actively treated group no longer achieved statistical significance. There was no corresponding improvement in urinary
symptoms in the placebo group, which changed little from the
baseline of 18.9 of 40 to 19.3 of 40 at 3 months (95% CI ⫺6.5
2046
ELECTROMAGNETIC THERAPY FOR MALE CHRONIC PELVIC PAIN SYNDROME
FIG. 2. Mean VAS pain and urinary symptom scores at baseline,
and 3 and 12 months in active and placebo groups.
FIG. 4. Mean urinary symptom scores in active and placebo
groups.
FIG. 3. Mean pain scores at baseline, and at 3-month and 1-year
followups.
to 5.64, p ⬎0.05) and 15.6 of 40 at 1 year (95% CI ⫺11.83 to
10.23, p ⬎0.05, fig. 4).
No significant side effects were observed. One patient in
the active group experienced transient paresthesia 48 hours
in duration with subsequent complete resolution.
DISCUSSION
In this pilot study we prospectively tested the hypothesis
that pelvic floor neuromuscular dysfunction/neurogenic inflammation may account for some symptoms of CPPS
(NIDDK IIIA and IIIB) and this dysfunction could be decreased by the noninvasive application of local electromagnetic therapy. Sustained improvement was observed in the
symptom scores of men in the active group compared with
scores those who received sham treatment.
When mean symptom scores were compared at 3 months
and 1 year, there was a statistically significant decrease of
approximately 40% in men in the active group, which was not
observed in the placebo group. Further subanalysis of VAS
pain and urinary symptom scores showed that the greatest
improvement in the symptom profile was seen in the pain
categories of men receiving active treatment, which was sustained at 1 year. There was also a significant improvement in
urinary symptoms at 3 months of followup in the active
group, although this decrease was of lower magnitude than
the improvement in pain symptoms (approximately 30%) and
it was no longer significantly different from baseline at 1
year. Nevertheless, no equivalent improvement was seen in
the placebo group. Although we did not test the effectiveness
of blinding the sham treatment group, we believe that the
differences that we observed represent a real effect through
mechanisms that have yet to be elucidated. Since this was a
pilot study, quantitative analysis of the effectiveness of blinding to active or placebo treatment was not done and this
should be part of any future study. However, because men in
each arm wrote to ask if they had received active treatment
at the 1-year followup, this anecdotal evidence reassured us
as to the effectiveness of blinding. The failure to obtain followup data on all of those who participated in the study is at
least in part a reflection of the transient nature of the urban
population in which this study was performed.
While the precise etiology of CPPS continues to be obscure,
there is growing evidence that it may result from muscular/
neural dysfunction of the lower urinary tract rather from
than an inflammatory process in the prostate gland, which is
supported by histological evidence and the failure of antibiotic treatment in a randomized, placebo controlled, multicenter trial.8, 18 Support for the theory that it may result from
a spasm in the proximal sphincter mechanism may derive
from the decrease in symptoms in men treated with
␣-blockers.13, 19 However, the pathways in neurogenic inflammation and in particular the complex interaction between central and peripheral nervous and the endocrine system, and their effects on immunomodulatory mechanisms
may provide an explanation for the symptom pattern seen in
men with CPPS. The modification/interruption of this pathway through electromagnetic stimulation may explain the
improved symptom profile in those who received active treatment. By breaking the cycle of tonic muscular spasm and
neural hypersensitivity/inflammation normal pelvic floor
muscular activity is restored. This may account for the durability of the response. Another possible explanation is that
purinergic P2X3 receptor subunits are up-regulated in CPPS,
as reported in interstitial cystitis, and this up-regulation is
reversed or there is desensitization of purinergic receptors
ELECTROMAGNETIC THERAPY FOR MALE CHRONIC PELVIC PAIN SYNDROME
12
following treatment. Interference of this pathway could
explain why pain symptoms showed the greatest response.
To date electromagnetic stimulation therapy has generally
been reserved for stress and urge female urinary incontinence. The frequencies used for this purpose were 10 and 50
Hz. Hence, these frequencies were applied in our phase II
study. It may be that a single frequency will suffice and
shorten treatment time, leading to cost savings. Frequencies
of 20 Hz have been used successfully in the treatment of
detrusor hyperreflexia, showing functional responses in the
pelvic sphincter muscles together with an inhibition of detrusor hyperreflexia, possibly via the activation of pudendal
nerve afferents blocking parasympathetic detrusor motor fibers at the spinal reflex arc.20 If the changing electromagnetic field exerts its effect in CPPS by decreasing tone in the
proximal sphincter mechanism, frequencies with a maximal
effect at this site may prove more effective.
The electromagnetic chair is unlikely to exert its effect on
pain pathways similar to a transcutaneous electrical nerve
stimulation machine. 1) This would not account for the improvement in urinary symptoms. 2) The transcutaneous electrical nerve stimulation machine operates at a much higher
frequency of 120 Hz. The noninvasive nature of electromagnetic stimulation treatment and the ease of repeating it if
necessary makes it attractive to patients and physicians
alike since it can be easily performed in the office environment.
CONCLUSIONS
In this study we noted the safe, effective and novel use of a
noninvasive pelvic floor stimulation device, that is the electromagnetic chair, for treating CPPS symptoms in a prospective, double-blind, placebo controlled study. These subjective
improvements at 3 months of followup in patients in whom
many other treatment regimens have previously failed were
durable in the majority at 1 year. Further large-scale multicenter studies are required fully to evaluate the efficacy of
this treatment and establish the optimal stimulation frequency as well as the usefulness of repeating treatment in
those in whom initial therapy fails. These studies should
incorporate the National Institute of Health CPPS index as a
primary outcome measure, which was unfortunately not published at the time of initiation of this study.
Robert Redfern assisted with statistical data analysis.
Neotonus™ provided the electromagnetic chair.
APPENDIX: VAS SCORES
Each symptom category was scored from 0 (asymptomatic)
to 10 (severe symptoms)
1) Pain or discomfort in the penis, testicles or scrotum
2) Pain or discomfort in the perineum (area where you sit,
between the testicles and anus)
3) Pain or discomfort in the suprapubic or bladder area
4) Pain or discomfort during ejaculation
5) Pain or discomfort in the low back, upper leg or groin
area
6) Uncomfortable and difficult urination (stranguria)
7) Voiding often (frequency)
8) Difficulty postponing urination (urgency)
9) Burning feeling during urination (dysuria)
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