Since their popularization over the past 2 decades, low-intensity shock wave (LiSWT) and pulse wave (often referred to as radial or acoustic wave) therapies have arguably become among the most heavily advertised treatments for erectile dysfunction (ED) in the U.S. However, despite the increasing number of multimedia campaigns and claims of efficacy, there often remains significant confusion regarding the therapies themselves and true data available.

Pulse Wave and Shock Wave Therapies Are Different

One of the most important distinctions to highlight regarding this technology is the difference between LiSWT and pulse wave therapies. Although the 2 terms are often used (confused) interchangeably, in reality, the therapies are very different in several critical aspects. The most important of these differences relates to the types and intensity of energy delivered. While LiSWT provides a high-energy, focused shock wave which results in local tissue trauma, pulse wave devices generate radial waves, which deliver significantly lower amounts of energy overall. These differences in energy are one reason why pulse wave therapies have lower U.S. Food and Drug Administration classifications compared to LiSWT devices and why nonmedical professionals are able to perform pulse wave therapies without licensure or certification, including direct-to-consumer sales of pulse wave devices (which are commonly misrepresented as LiSWT devices).

The nomenclature used to describe the therapies is also commonly confused. For sake of simplicity, in reference to ED therapies, the terms “pulse,” “pressure” and “radial” can be considered synonymous and most often refer to instruments which generate the lower amplitude (power) radial waves. In contrast, the term “shock wave” only applies to devices which generate a true, focal shock wave, whereas terms such as “acoustic wave” could be used to define either pulse wave or LiSWT, since they both deliver acoustic energy. It is therefore incorrect and misleading to refer to any therapy which only delivers low-amplitude pulse/radial/pressure waves as LiSWT, although this is commonly done with many online and direct-to-consumer advertisements.

Data Cannot Be Extrapolated between Therapies

Importantly, since LiSWT and pulse wave therapies represent distinct treatments, the data regarding their efficacy cannot be extrapolated to one another. More pointedly stated, it is misleading for any individual or group to suggest that results from LiSWT can be used to suggest similar benefits with pulse wave treatments, and vice versa. Indeed, given the differences in energy delivered, it would be relatively akin (although exaggerated) to comparing outcomes of shock wave therapy for nephrolithiasis to someone receiving a renal ultrasound.

In reviewing published results, a relatively large amount of data has been generated regarding the safety and efficacy of LiSWT, including several randomized controlled trials (RCTs). In a recent, large meta-analysis of 16 RCTs evaluating LiSWT for ED, Yao and colleagues identified an average improvement of 3 points in the International Index of Erectile Function-Erectile Function Domain score compared to sham-treated men.¹ Although these results are statistically significant, they fail to meet the 4-point threshold required to be considered clinically meaningful as an ED therapy.² These data are similar to other meta-analyses which have reported improvements ranging from 2 to 5 points and which underscore the controversial nature of LiSWT as an “effective” ED therapy.

However, in contrast to the abundant number of RCTs available in men receiving LiSWT, until recently, no RCTs had been performed evaluating the efficacy of pulse wave treatments in men with ED. This fact is remarkable given the volume of advertising and statements which have been made over 2 decades suggesting an abundance of scientific proof on the topic.

New Published Data on Pulse Wave Therapy and Societal Statements

In May 2022, The Journal of Sexual Medicine published the first ever randomized, double-blinded, sham-controlled clinical trial evaluating pulse/radial wave therapy for ED.³ Results from the study of 80 men demonstrated that pulse/radial wave therapy had no impact on improving erectile function, with controls showing a nonstatistically greater improvement compared to pulse wave treated men. These data are important, as they demonstrate that pulse wave therapy provides no benefits for the treatment of ED. They also strongly undermine any advertising claims for efficacy of pulse wave devices or therapies.

From a medical societal standpoint, although several statements reference LiSWT in the management of ED and/or Peyronie’s disease, none has specifically highlighted pulse wave therapy. More broadly, SMSNA (Sexual Medicine Society of North America) has released a position statement on restorative therapies and concluded that “the use of shock waves or stem cells/[stromal vascular fraction cells] is investigational…and should only be conducted under research protocols in compliance with institutional review board approval at little or no cost to the patient. Specifically, SMSNA does not feel that it is appropriate or ethical for providers to advertise or otherwise make implicit or explicit claims of efficacy for these therapies pending further data. Similarly, patients considering such therapies should be fully informed as to the lack of data demonstrating clinically relevant efficacy and consented regarding the potential benefits and risks.”⁴

Take-Home Message

Pulse wave (radial/pressure wave) therapies represent a distinct treatment from LiSWT and have limited published data available. Recently, the first RCT evaluating the efficacy of pulse wave therapy failed to demonstrate any benefits with treatment compared to sham controls. These findings, in combination with a lack of supporting data, would suggest that pulse wave therapy currently has no role in the treatment of ED. The use of pulse wave therapy for this condition would also be considered against best practices and is not in keeping with evidence-based medicine. Advertising or claims which suggest benefits for pulse wave therapies/devices or which indirectly suggest benefits through extrapolation of LiSWT data are not consistent with contemporary clinical data and are therefore misleading.