Comparison of Hands-free Ultrasound and Traditional
Ultrasound for Therapeutic Treatment

Melanson
H., Draper DO., Mitchell UH., Eggett DL.
Athl
Train Sports Health Care
2016;8(4):177-184

Take Home Message: A hands-free
ultrasound unit at 1 MHz failed to increase the temperature deep in the
gastrocnemius after 10 minutes.

Therapeutic
ultrasound is an effective deep heating modality (heating to a depth of ~2 to 5
cm) when used properly. Traditional ultrasound treatments are labor intensive,
time consuming, and prone to clinician error (e.g., treating too large an area,
moving the sound head too fast). There is a hands-free ultrasound unit;
however, there is little research whether the hands-free unit produces the same
deep heating effects as traditional ultrasound. Therefore, the authors
conducted a randomized cross-over experiment with 16 healthy participants (6
males and 10 females, age ~22 years, average gastrocnemius subcutaneous fat
thickness ~0.85 cm) to determine whether the Rich-Mar AutoSound
would be as effective as a traditional ultrasound at increasing the temperature
of the gastrocnemius muscle during a 10-minute, 1 MHz, 1.0 W/cm2  treatment. Each participant received
the treatment over their left gastrocnemius with both the hands-free and traditional
ultrasound unit with 24 hours between treatments. The treatment area was two
times the size of the ultrasound heads. The authors measured the participants’ muscle
temperature every 30 seconds during the ultrasound treatments using a
thermistor inserted ~2.25 cm deep in the triceps surae muscle. The depth was
verified with ultrasound imaging. The authors found that the hands free
ultrasound was not effective at increasing the temperature of the gastrocnemius
muscle because temperature decreased 0.16°C during treatment. The traditional ultrasound
had a total temperature increase of 0.41°C (rate of warming ~ 0.025°C per minute).

This
is an important study because as technology advances and more instruments come
on the market it is necessary to test them and have evidence to support the
purchase and implementation of a new device into practice. The authors of this
study demonstrated that the hands-free ultrasound device was not effective for
heating deep tissues at 1 MHz. They suggested that the hands free device failed
to deliver a beneficial heating effect due to the location and activation of
the 4 crystal heads and the use of 10-mm thick gel pads (previous research demonstrated that 2- to 3-mm gel pads are more effective). The
traditional ultrasound treatment increased the gastrocnemius temperature but it
was likely insufficient for clinical benefit. Medical professionals should be
aware of the effectiveness of their tools as well as the reliability and
validity of their own technique in handling the device. It would be interesting
to see this study repeated in an injured population with damaged tissue to
evaluate the outcomes related with the ultrasound units. For example, it is
unclear how the placebo effect differs between a clinician provided ultrasound
treatment versus a hands-free treatment. Lastly, medical professionals need to
work with manufacturers to produce and evaluate products before they are
available on the market. As Christopher Ingersoll described in It’s Time For Evidence, it is not the manufactures
responsibility to provide us with research to support their product’s clinical
effectiveness. It is our job as medical professionals to see how effective
these devices are within our respective roles and populations.

Questions for Discussion:
Do you use ultrasound as a deep heating modality? If so, do you find it to be
effective? Would you be interested in a hands-free ultrasound device?

Written
by: Jane McDevitt, PhD
Reviewed
by: Jeff Driban

Related
Posts
:

American Medical Society for Sports Medicine (AMSSM) Position Statement: Interventional Musculoskeletal Ultrasound in Sports Medicine


Melanson, H., Draper, D., Mitchell, U., & Eggett, D. (2016). Comparison of Hands-free Ultrasound and Traditional Ultrasound for Therapeutic Treatment Athletic Training & Sports Health Care, 8 (4), 177-184 DOI: 10.3928/19425864-20160505-01