Medical Policy

Policy Num:      08.001.061
Policy Name:    Stationary Ultrasonic Diathermy Devices
Policy ID:          [08.001.061]  [Ac / B / M - / P-]  [7.01.174]

Last Review:       February 17, 2026
Next Review:      February 15, 2027

Publication Date: March 2026

Related Policies:
08.001.060 - Dry Hydrotherapy for chronic pain conditions
02.001.031 - Biofeedback as a Treatment of Chronic Pain

Stationary Ultrasonic Diathermy Devices

Summary

Description

An ultrasonic diathermy device applies ultrasonic energy to specific body parts at a frequency higher than 20 kilohertz in order to generate deep heat within body tissues for the treatment of certain medical conditions, such as the alleviation of pain, muscle spasms, and joint contractures. Newer portable stationary devices can be self-applied and used at home to deliver diathermy via continuous low-intensity therapeutic ultrasound. Electrodes attached to adhesive bandages are applied to the skin over the desired treatment area. The continuous low-intensity ultrasound unit can provide treatment for several hours.

Summary of Evidence

For individuals with musculoskeletal pain treated with stationary ultrasonic diathermy devices, the evidence includes a meta-analysis and 3 RCTs. Relevant outcomes are symptoms, functional outcomes, quality of life, and medication use. The meta-analysis included 13 studies of participants with musculoskeletal injuries divided into 3 treatment areas: upper shoulder, neck, and back; knee joint; and soft tissue injuries of the musculoskeletal system. The following clinical outcomes were evaluated: pain, function, and diathermy. The meta-analysis demonstrated that therapy with a SAM device reduced pain, improved overall health quality, and generated deep therapeutic heat. In 2 RCTs that are also included in the meta-analysis, treatment with a SAM device for 4 hours daily for 4 to 6 weeks improved pain scores in individuals with upper trapezius myofascial pain and mild to moderate knee osteoarthritis with moderate to severe associated pain. An additional RCT reported that treatment with a SAM device for 4 hours daily for 8 weeks demonstrated improvements in pain scores in individuals with chronic lower back pain. Limitations of the available data include heterogeneity in treatment areas, treatment implementation, and clinical outcomes, as well as small sample sizes and short follow-up. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

Additional Information

Not applicable.

Objective

The objective of this evidence review is to determine whether the use of stationary ultrasonic diathermy devices improves the net health outcome in individuals with musculoskeletal pain.

Policy Statements

Ultrasonic diathermy devices for the treatment of musculoskeletal pain are considered investigational.

Policy Guidelines

Individuals with certain medical conditions may not be appropriate candidates for diathermy, including but not limited to those:

• with an implanted medical device (pacemaker, deep brain stimulation device, etc);

• with a healing fracture in the area to be treated;

• with a malignancy in the area to be treated;

• who are pregnant.

Coding

See the Codes table for details.

Benefit Application

BlueCard/National Account Issues

Ultrasonic diathermy may be offered as part of a comprehensive program in pain management as offered by pain management centers.

Benefits are determined by the group contract, member benefit booklet, and/or individual subscriber certificate in effect at the time services were rendered.  Benefit products or negotiated coverages may have all or some of the services discussed in this medical policy excluded from their coverage.

Background

Therapeutic Ultrasound

Therapeutic ultrasound is a noninvasive method used to treat a variety of musculoskeletal conditions.^1, Therapeutic ultrasound produces acoustic vibrations of high frequency (≥20 kilohertz) that are outside the range of human hearing.^2, The vibrations generated during therapeutic ultrasound allow the body to generate heat in targeted tissues that are high in collagen (muscles, tendons, ligaments, etc); this is referred to as ultrasound/ultrasonic diathermy. The increased vibrations and heat to the affected areas simulate soft tissue injury repair and pain relief.

Conventionally, high-frequency/high-intensity therapeutic ultrasound is provided in a clinic setting with an average length of treatment ranging from 5 to 10 minutes per session.^1,2, In this setting, the ultrasound is transmitted through a wand that is applied to the skin with gentle, circular movements. A hypo-allergenic gel aids in the transmission of ultrasonic energy and prevents overheating at the surface of the applicator.

It is important to note that individuals with implanted metal devices, including pacemakers, prostheses, and intrauterine devices, are at risk of serious injury if they undergo diathermy.^1, Furthermore, patients with certain medical conditions, including cancer and others, may not be appropriate candidates for diathermy.

Ultrasonic Diathermy Devices

Newer portable/wearable, stationary devices can be used at home to deliver diathermy via continuous low-intensity therapeutic ultrasound.^3, Electrodes attached to adhesive bandages are self-applied to the skin over the desired treatment area. This type of treatment may also be referred to as sustained acoustic medicine. Similar to conventional high-frequency/high-intensity therapeutic ultrasound, a high-frequency/low-intensity ultrasonic diathermy device applies ultrasonic energy to specific body parts in order to generate deep heat within body tissues for the treatment of certain medical conditions, such as the alleviation of pain, muscle spasms, and joint contractures. The continuous low-intensity ultrasound device provides treatment for several hours.

Regulatory Status

Several stationary ultrasonic diathermy devices have been granted 510(k) clearance by the United States Food and Drug Administration (FDA) including Manasport^™ (ManaMed, Inc., Las Vegas, NV), Sustained Acoustic Medicine (sam^®) (ZetrOZ^™, Inc., Trumbull, CT), and PainShield^™ MD (NanoVibronix Inc., Elmsford, NY), and Ultrasound Stimulator (Jkh USA, Irvine, CA). The intended use of these devices is to supply ultrasound “to generate deep heat within body tissues for the treatment of selected medical conditions such as the relief of pain, muscle spasms, joint contractures, and increase local circulation.”

FDA product code: PFW

Rationale

This evidence review was created in October 2022 with a search of the PubMed database. The most recent literature update was performed through December 1, 2025.

Evidence reviews assess the clinical evidence to determine whether the use of a technology improves the net health outcome. Broadly defined, health outcomes are length of life, quality of life, and ability to function including benefits and harms. Every clinical condition has specific outcomes that are important to patients and to managing the course of that condition. Validated outcome measures are necessary to ascertain whether a condition improves or worsens; and whether the magnitude of that change is clinically significant. The net health outcome is a balance of benefits and harms.

To assess whether the evidence is sufficient to draw conclusions about the net health outcome of a technology, 2 domains are examined: the relevance and the quality and credibility. To be relevant, studies must represent one or more intended clinical use of the technology in the intended population and compare an effective and appropriate alternative at a comparable intensity. For some conditions, the alternative will be supportive care or surveillance. The quality and credibility of the evidence depend on study design and conduct, minimizing bias and confounding that can generate incorrect findings. The randomized controlled trial (RCT) is preferred to assess efficacy; however, in some circumstances, nonrandomized studies may be adequate. Randomized controlled trials are rarely large enough or long enough to capture less common adverse events and long-term effects. Other types of studies can be used for these purposes and to assess generalizability to broader clinical populations and settings of clinical practice.

Population Reference No. 1 

Musculoskeletal Pain

Clinical Context and Therapy Purpose

The purpose of stationary ultrasonic diathermy devices in individuals who have musculoskeletal pain is to provide a treatment option that is an alternative to or an improvement on existing therapies. For chronic pain management, a multimodal, multidisciplinary approach that is individualized to the individual is recommended.^4, A multimodal approach to pain management consists of using treatments (ie, nonpharmacologic and pharmacologic) from 1 or more clinical disciplines incorporated into an overall treatment plan. This allows for different avenues to address the pain condition, often enabling a synergistic approach that impacts various aspects of pain, including functionality. The efficacy of such a coordinated, integrated approach has been documented to reduce pain severity, improve mood and overall quality of life, and increase function.

The following PICO was used to select literature to inform this review.

Populations

The relevant populations of interest are individuals with musculoskeletal pain.

Interventions

The therapy being considered is stationary ultrasonic diathermy devices. This type of treatment may also be referred to as low-intensity continuous ultrasound or sustained acoustic medicine (SAM).

Comparators

The following therapies are currently being used to treat musculoskeletal pain: pharmacologic and nonpharmacologic therapy.

Outcomes

The general outcomes of interest are reductions in symptoms, functional outcomes, quality of life, medication usage, and health resource utilization.

Study Selection Criteria

Methodologically credible studies were selected using the following principles:

• To assess efficacy outcomes, comparative controlled prospective trials were sought, with a preference for RCTs;

• In the absence of such trials, comparative observational studies were sought, with a preference for prospective studies.

• To assess long-term outcomes and adverse events, single-arm studies that capture longer periods of follow-up and/or larger populations were sought.

• Consistent with a 'best available evidence approach,' within each category of study design, studies with larger sample sizes and longer durations were sought.

• Studies with duplicative or overlapping populations were excluded.

Review of Evidence

Systematic Reviews

Systematic reviews evaluating the clinical effects of stationary ultrasonic diathermy devices on musculoskeletal conditions are summarized in Tables 1 and 2. A crosswalk of studies included in the meta-analyses is provided in the appendix (Table A1).

Winkler et al (2022) summarized the clinical effects of the sustained acoustic medicine (sam^®) device versus placebo control in individuals with musculoskeletal injuries.^5, The analysis included 13 studies divided into 3 treatment areas: upper shoulder, neck, and back (3 studies); knee joint (4 studies); and soft tissue injuries of the musculoskeletal system (6 studies). The following clinical outcomes were evaluated: pain, function, and diathermy. Overall, therapy with a SAM device reduced pain, improved overall health quality, and generated deep therapeutic heat. Limitations of this analysis included heterogeneity in treatment area, therapy implementation, and clinical outcomes, small sample sizes, and short follow-up.

Table 1. SR & M-A Characteristics

  M-A: meta-analysis; RCT: randomized controlled trial; SAM: sustained acoustic medicine; SR: systematic review. 

Table 2. SR & M-A Results

  CI: confidence interval; M-A: meta-analysis; SAM: sustained acoustic medicine; SMD: standard mean difference; SR: systematic review. 

Randomized Controlled Trials

One RCT (Ortiz et al 2024) was published after the Winkler et al (2022) systematic review evaluating the clinical effects of stationary ultrasonic diathermy devices on musculoskeletal pain.

Six RCTs were included in the Winkler review (Lewis et al [2013], Petterson et al [2020], Langer et al [2015], Draper et al [2018], Rigby et al [2015], and Langer et al [2017]), of which 3 were rated as "excellent quality" using the Downs and Black checklist for quality evaluation of RCTs and non-RCTs.^{6,7,8,9,10,11,} Two of the 3 studies rated as "excellent quality" are summarized in Tables 3 and 4 (Petterson et al [2020] and Draper et al [2018]).^7,9, The third study rated as excellent quality (Langer et al [2017]) was done in healthy individuals and did not evaluate relevant clinical outcomes.^11,

Table 3. Summary of Key RCT Characteristics

  NR: not reported; NRS: numeric rating scale; RCT: randomized controlled trial; SAM: sustained acoustic medicine.

Table 4. Summary of Key RCT Results

  CI: confidence interval; GROC: Global Rate of Change Score (range, 0 [no change in pain] to 15); NRS: numeric rating scale (range, 0 [no pain] to 10); RCT: randomized controlled trial; SAM: sustained acoustic medicine; WOMAC: Western Ontario McMaster Osteoarthritis Questionnaire.

The purpose of the study limitations tables (see Tables 5 and 6) is to display notable limitations identified in each study. This information is synthesized as a summary of the body of evidence following each table and provides the conclusions on the sufficiency of evidence supporting the position statement.

Table 5. Study Relevance Limitations

  The study limitations stated in this table are those notable in the current review; this is not a comprehensive gaps assessment.  a Population key: 1. Intended use population unclear; 2. Study population is unclear; 3. Study population not representative of intended use; 4, Enrolled populations do not reflect relevant diversity; 5. Other. b Intervention key: 1. Not clearly defined; 2. Version used unclear; 3. Delivery not similar intensity as comparator; 4. Not the intervention of interest (e.g., proposed as an adjunct but not tested as such); 5: Other. c Comparator key: 1. Not clearly defined; 2. Not standard or optimal; 3. Delivery not similar intensity as intervention; 4. Not delivered effectively; 5. Other. d Outcomes key: 1. Key health outcomes not addressed; 2. Physiologic measures, not validated surrogates; 3. Incomplete reporting of harms; 4. Not establish and validated measurements; 5. Clinically significant difference not prespecified; 6. Clinically significant difference not supported; 7. Other. e Follow-Up key: 1. Not sufficient duration for benefit; 2. Not sufficient duration for harms; 3. Other.

Table 6. Study Design and Conduct Limitations

  The study limitations stated in this table are those notable in the current review; this is not a comprehensive gaps assessment. a Allocation key: 1. Participants not randomly allocated; 2. Allocation not concealed; 3. Allocation concealment unclear; 4. Inadequate control for selection bias; 5. Other. b Blinding key: 1. Participants or study staff not blinded; 2. Outcome assessors not blinded; 3. Outcome assessed by treating physician; 4. Other. c Selective Reporting key: 1. Not registered; 2. Evidence of selective reporting; 3. Evidence of selective publication; 4. Other. d Data Completeness key: 1. High loss to follow-up or missing data; 2. Inadequate handling of missing data; 3. High number of crossovers; 4. Inadequate handling of crossovers; 5. Inappropriate exclusions; 6. Not intent to treat analysis (per protocol for noninferiority trials); 7. Other. e Power key: 1. Power calculations not reported; 2. Power not calculated for primary outcome; 3. Power not based on clinically important difference; 4. Other. f Statistical key: 1. Analysis is not appropriate for outcome type: (a) continuous; (b) binary; (c) time to event; 2. Analysis is not appropriate for multiple observations per patient; 3. Confidence intervals and/or p values not reported; 4. Comparative treatment effects not calculated; 5. Other.

Section Summary: Musculoskeletal Pain

A meta-analysis evaluated the clinical effects of a SAM device versus control for patients with musculoskeletal injuries. The analysis included 13 studies divided into 3 treatment areas: upper shoulder, neck, and back (3 studies, including 2 RCTs); knee joint (4 studies, including 2 RCTs); and soft tissue injuries of the musculoskeletal system (6 studies, including 2 RCTs). The following clinical outcomes were evaluated: pain, function, and diathermy. Overall, therapy with a SAM device reduced pain, improved overall health quality, and generated deep therapeutic heat. In 2 RCTs included in the meta-analysis, treatment with a SAM device for 4 hours daily for 4 to 6 weeks demonstrated improvements in pain scores in individuals with upper trapezius myofascial pain and mild to moderate knee osteoarthritis with moderate to severe associated pain. An additional RCT reported that treatment with a SAM device for 4 hours daily for 8 weeks demonstrated improvements in pain scores in individuals with chronic lower back pain. Limitations of the available data include heterogeneity in treatment areas, treatment implementation, and clinical outcomes, as well as small sample sizes and short follow-up.

Summary of Evidence

For individuals with musculoskeletal pain treated with stationary ultrasonic diathermy devices, the evidence includes a meta-analysis and 3 RCTs. Relevant outcomes are symptoms, functional outcomes, quality of life, and medication use. The meta-analysis included 13 studies of participants with musculoskeletal injuries divided into 3 treatment areas: upper shoulder, neck, and back; knee joint; and soft tissue injuries of the musculoskeletal system. The following clinical outcomes were evaluated: pain, function, and diathermy. The meta-analysis demonstrated that therapy with a SAM device reduced pain, improved overall health quality, and generated deep therapeutic heat. In 2 RCTs that are also included in the meta-analysis, treatment with a SAM device for 4 hours daily for 4 to 6 weeks improved pain scores in individuals with upper trapezius myofascial pain and mild to moderate knee osteoarthritis with moderate to severe associated pain. An additional RCT reported that treatment with a SAM device for 4 hours daily for 8 weeks demonstrated improvements in pain scores in individuals with chronic lower back pain. Limitations of the available data include heterogeneity in treatment areas, treatment implementation, and clinical outcomes, as well as small sample sizes and short follow-up. The evidence is insufficient to determine that the technology results in an improvement in the net health outcome.

Supplemental Information

The purpose of the following information is to provide reference material. Inclusion does not imply endorsement or alignment with the evidence review conclusions.

Practice Guidelines and Position Statements

Guidelines or position statements will be considered for inclusion in 'Supplemental Information' if they were issued by, or jointly by, a US professional society, an international society with US representation, or National Institute for Health and Care Excellence (NICE). Priority will be given to guidelines that are informed by a systematic review, include strength of evidence ratings, and include a description of management of conflict of interest.

No guidelines that discuss the role of stationary ultrasonic diathermy devices in individuals with musculoskeletal pain were identified.

Medicare National Coverage

There is no national coverage determination. In the absence of a national coverage determination, coverage decisions are left to the discretion of local Medicare carriers.

Ongoing and Unpublished Clinical Trials

Some currently unpublished trials that might influence this review are listed in Table 7.

Table 7. Summary of Key Trials

  NCT: national clinical trial. a Denotes industry-sponsored or cosponsored trial.

References

1. U.S. Food and Drug Administration. Policy Clarification and Premarket Notification [510(k)] Submissions for Ultrasonic Diathermy Devices. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/policy-clarification-and-premarket-notification-510k-submissions-ultrasonic-diathermy-devices. Updated February 21, 2023. Accessed November 25, 2025.
2. Matthews MJ, Stretanski MF. Ultrasound Therapy. In: StatPearls [Internet]. StatPearls Publishing; 2023.
3. Uddin SMZ, Komatsu DE, Motyka T, et al. Low-Intensity Continuous Ultrasound Therapies—A Systematic Review of Current State-of-the-Art and Future Perspectives. J Clin Med. Jun 18 2021; 10(12). PMID 34207333
4. U.S. Department of Health and Human Services. Pain management best practices. May 2019. https://www.hhs.gov/sites/default/files/pmtf-final-report-2019-05-23.pdf. Accessed December 1, 2025.
5. Winkler SL, Urbisci AE, Best TM. Sustained acoustic medicine for the treatment of musculoskeletal injuries: a systematic review and meta-analysis. BMC Sports Sci Med Rehabil. Dec 18 2021; 13(1): 159. PMID 34922606
6. Lewis GK, Langer MD, Henderson CR, et al. Design and evaluation of a wearable self-applied therapeutic ultrasound device for chronic myofascial pain. Ultrasound Med Biol. Aug 2013; 39(8): 1429-39. PMID 23743101
7. Petterson S, Plancher K, Klyve D, et al. Low-Intensity Continuous Ultrasound for the Symptomatic Treatment of Upper Shoulder and Neck Pain: A Randomized, Double-Blind Placebo-Controlled Clinical Trial. J Pain Res. 2020; 13: 1277-1287. PMID 32606899
8. Langer MD, Lewis GK. Sustained Acoustic Medicine: A Novel Long Duration Approach to Biomodulation Utilizing Low Intensity Therapeutic Ultrasound. Proc SPIE Int Soc Opt Eng. May 2015; 9467. PMID 30078928
9. Draper DO, Klyve D, Ortiz R, et al. Effect of low-intensity long-duration ultrasound on the symptomatic relief of knee osteoarthritis: a randomized, placebo-controlled double-blind study. J Orthop Surg Res. Oct 16 2018; 13(1): 257. PMID 30326947
10. Rigby JH, Taggart RM, Stratton KL, et al. Intramuscular Heating Characteristics of Multihour Low-Intensity Therapeutic Ultrasound. J Athl Train. Nov 2015; 50(11): 1158-64. PMID 26509683
11. Langer MD, Byrne HK, Henry T, et al. The effect of low intensity wear-able ultrasound on blood lactate and muscle performance after high intensity resistance exercise. J Exerc Physiol. 2017;20(4):132-146.
12. Ortiz R, Motyka T, Petterson S, et al. Sustained acoustic medicine treatment of discogenic chronic low back pain: A randomized, multisite, double-blind, placebo-controlled trial. J Back Musculoskelet Rehabil. 2024; 37(5): 1321-1332. PMID 38905030

Codes

Policy History