Comments on proposed order “Physical Medicine Devices: Reclassification and Renaming of Shortwave Diathermy of All Other Uses”

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Division of Dockets Management
Food and Drug Administration
5630 Fishers Lane, Room 1061 (HFA-305)
Rockville, Maryland 20852

May 21, 2014

Comments of the National Center for Health Research
On proposed order
“Physical Medicine Devices: Reclassification and Renaming of Shortwave Diathermy of All Other Uses”
[Docket No. FDA-2012-N-0378]

The National Center for Health Research strongly opposes the reclassification of the shortwave diathermy (SWD) for any use into class II (special controls).  Because FDA is renaming the device to “nonthermal shortwave therapy (SWT) devices,” we will be referring to the devices by that name in these comments.

Industry has stated that their product is effective, but we agree with the assessment that the FDA made in 2013 that the product is not proven effective. Of the six studies cited by an industry coalition at the May 21, 2013 Orthopaedic and Rehabilitation Devices meeting, none use appropriate statistical methods or pre-defined endpoints, and therefore cannot provide evidence that the devices are effective. Two of the studies evaluating pain showed no benefit, and one had mixed results. Therefore, we conclude that there is no clear evidence that the product is effective.

It is important to note that the Advisory Panel at the May 21, 2013 meeting expressed concerns about the lack of evidence regarding effectiveness of SWT devices. According to the February 20, 2014 Federal Register notice, the panel indicated there was “limited clinical evidence presented to demonstrate effectiveness” of nonthermal SWT devices and that there were “concerns about the veracity and the limitations of clinical trials reported in the literature.”   Although panel members were willing to downclassify the devices, they recommended special controls including clinical performance data prior to clearance to address the issue of ineffective treatment.  Unfortunately, panel members were not informed that clinical performance data is less rigorous than the clinical trials that are required for a PMA application.

The FDA has identified other special controls that it states “Would provide reasonable assurance of their [nonthermal SWT devices] safety.”[1]  These might possibly be adequate if the device was clearly beneficial; however, in the absence of clear evidence that the device is effective, any health risks would not be acceptable. The FDA acknowledges that when they stated, “Ineffective treatments can result in increased morbidity, delayed discharge after ambulatory surgery, and hospital readmission.”1

In contrast to the lack of evidence about effectiveness, there is clear evidence that the product can harm patients.  In this 2014 proposed order, FDA has identified nine health risks associated with nonthermal SWT devices: cellular or tissue injury, electromagnetic interference, tissue necrosis and burns, electrical shock, thermal injury from implanted leads, adverse tissue reaction, adverse pregnancy outcome, risk to children (the device can affect the growth plates in children), and ineffective treatment. These are very significant risks; MAUDE reports regarding these devices included blisters, third degree burns, shock sensations, and interference with a pacemaker.[2]

Unfortunately, none of the six studies industry cited systematically measured and recorded adverse events, thus providing no scientific evaluation on safety.  In addition, the studies were too small to appropriately measure adverse reactions, with only three of the six studies including at least participants and none with more than 100.

The FDA has stated that it “has been reviewing these devices for many years, and their risks are well known.”  We disagree.  A tiny percentage of adverse reactions are reported to the MAUDE database, making it impossible to know how frequently adverse reactions occur.

Pain management is serious business.  The FDA has approved several prescription drugs with clear risks of addiction.  If the FDA is willing to clear unproven medical devices aimed at reducing pain rather than requiring evidence of effectiveness, the unintended consequence will be more prescriptions for pain medication, including the drugs that have been proven to be most addictive.

We urge the FDA to keep nonthermal SWT devices as class III devices and require a PMA as FDA originally recommended in its 2012 proposed rule.  General and special controls cannot compensate for a lack of safety and effectiveness evidence.  Downgrading these devices to class II is not justified.  By requiring a PMA, companies would be required to prove that their products are safe and effective.

For more information, contact Paul Brown at (202) 223-4000 or


[1] Federal Register (February 20, 2014). Physical Medicine Devices: Reclassification and Renaming of Shortwave Diathermy for All other Uses. [Docket No. FDA-2012-N-0378].


[2] Manufacturer and User Facility Device Experience (MAUDE) search for Produce Code ILX (Diathermy, Shortwave, For Use Other Than Applying Therapeutic Deep Health) from January 2001 through September 2012.