Sustained acoustic medicine: wearable, long duration ultrasonic therapy for the treatment of tendinopathy

Abstract

Objectives: The effectiveness of sustained acoustic medicine to alleviate pain and improve function in subjects with elbow or Achilles tendinopathy was evaluated through a level IV case series study. Subjects were trained to self-apply the wearable, long-duration, low-intensity ultrasonic device on their affected body part at home for 4 hours a day, at least 5 times per week over 6 weeks. Twenty-five subjects with clinician-diagnosed tendinopathy of the elbow (medial or lateral epicondyle) or Achilles tendon were enrolled. Methods: Pain measurements were recorded before, during, and after daily intervention using an 11-point numeric rating scale (NRS). Function of the injured limb was assessed biweekly using dynamometry. Repeated measures ANOVAs and paired-samples t-tests were used to examine the effect of treatment over time. Results: Among subjects with elbow tendinopathy (n = 20), a 3.94 ± 2.15 point reduction in pain (p = 0.002) was observed over the 6-week study and a 2.83 ± 5.52 kg improvement in grip strength (p = 0.04) was observed over the first two weeks. In addition, a significant reduction in pain was observed within the 4-h treatment sessions (p < 0.001). Among 5 subjects with Achilles tendinopathy, a reduction in pain and improvement in strength was also observed. Conclusions: Daily multi-hour ultrasonic therapy was associated with improved pain and increased function in subjects with chronic tendon injuries. This trial showed the safety and feasibility of self-administration of sustained acoustic medicine, and suggests that this therapy may be clinically beneficial in the treatment of tendinopathies of the elbow and Achilles tendon. A randomized controlled trial appears warranted to more definitively investigate the therapeutic potential of this treatment modality. Registered at www.ClinicalTrials.gov, NCT02466308

Keywords:

• Therapeutic ultrasound
• LITUS
• Tendinopathy
• Pain
• Sustained acoustic medicine

Acknowledgments

The authors wish to acknowledge Matt Langer, Ph.D. and Kerri Pierz, Ph.D. (ZetrOZ, Inc.) for their contributions to writing and editing the manuscript, respectively.

Declaration of interest

Funding for this study was provided by ZetrOZ, Inc.. TM Best is a paid consultant for ZetrOZ. G Lewis is founder and president of ZetrOZ. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.