Shockwave Therapy: New Research Indicates ESWT is Effective Treatment for Musculoskeletal Conditions | Southeast Sports Seminars

Shockwave Therapy: New Research Indicates ESWT is Effective Treatment for Musculoskeletal Conditions

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Long ago shockwave therapy was thought to be only effective for disintegrating urinary stones.  This cutting-edge technology has been used for over four decades by the medical community, but new research continues to emerge indicating its efficacy as a treatment intervention for musculoskeletal disorders as well.

An article titled, The Role of Extracorporeal Shockwave Treatment in Musculoskeletal Disorders was recently published in the Journal of Bone and Joint Surgery exploring the current evidence on the physical and biological principles, mechanism of action, clinical indications, and controversies of ESWT.

Physical Principles and Wave Generation

“Two types of technical principles are included in ESWT—focused ESWT (F-ESWT) and radial pressure waves (RPW), which are often referred to in the literature as radial shockwaves. These 2 technologies differ in their generation devices, physical characteristics, and mechanism of action, but they share several indications.”

Three core shockwave generation principles are used for Focused Extracorporeal Shockwave Therapy (F-ESWT):

  1. Electrohydraulic sources – produce a plasma bubble by high-voltage discharge between 2 electrodes in water
  2. Electromagnetic sources – In the first system, a high-voltage pulse is sent through a coil, which is opposite a metallic membrane.
  3. Piezoelectric sources – produce shockwaves by a high-voltage discharge across a pattern of piezoelectric elements mounted on the inner surface of a spherical backing that is placed inside a fluid-filled cavity.

“In RPW generators, compressed air accelerates a projectile inside a cylindrical guiding tube. When the projectile hits an applicator at the end of the tube, a pressure wave is produced and radially expands into the target tissue. These devices do not emit shockwaves because the rise times of the pressure pulses are too long and the pressure outputs are too low (Fig. 2). Nevertheless, RPW may induce acoustic cavitation.”

Mechanism of Action

Although there is a long history of the clinical success of shockwave treatments, the mechanism of action remains unknown.   According to the article, in 1997, Haupt proposed the following 4 possible mechanisms of reaction phases of ESWT on tissue10.

  1. Physical Phase – this phase indicates that the shockwave causes a positive pressure to generate absorption reflection, refraction, and transmission of energy to tissues and cells.
  2. Physiochemical Phase – ESWT stimulates cells to release biomolecules, such as adenosine triphosphate (ATP), to activate cell signal pathways.
  3. Chemical Phase – In this phase, shockwaves alter the functions of ion channels in the cell membrane and the calcium mobilization in cells.
  4. Biological Phase – Previous studies have shown that ESWT modulates angiogenesis, vascular endothelial growth factor, endothelial nitric oxide synthase, and proliferating cell nuclear antigen, anti-inflammatory effects (soluble intercellular adhesion molecule and soluble vascular cell adhesion molecule, wound-healing, and bone-healing, osteocalcin, alkaline phosphatase, dickkopf-related protein, and insulin-like growth factor.

“According to the article, it also appears that ESWT participates in mechanotransduction, producing biological responses through mechanical stimulation on tissues.”

Clinical Indications

At this point, I’m sure you’re wondering how this relates to conditions you treat within your scope of practice–what does the research indicate for the treatment of musculoskeletal conditions and disorders?

“ESWT is indicated in chronic tendinopathies in which conventional conservative treatment is considered unsatisfactory after a prolonged and comprehensive management or as an alternative to surgery in patients with nonunion. ESWT is a noninvasive alternative in select cases when the indication for surgical treatment arises.

The International Society for Medical Shockwave Treatment (ISMST) has developed a list of approved clinical indications that are based on the strength of the supporting evidence53. The recommendations for ESWT indications and contraindications are summarized in Table II and Table III, respectively.”

Shoulder Tendinopathies

Calcifying Tendinopathy of the Shoulder (CTS) – Several systematic reviews and meta-analyses have demonstrated that high-energy F-ESWT is a safe, effective treatment for CTS.

Noncalcifying Tendinopathy of the Shoulder – the authors stated that they are unable to recommend the use of ESWT in noncalcific tendinopathy of the shoulder because of the lack of compelling evidence.

Lateral Epicondylopathy of the Elbow

ESWT was approved by the FDA as a treatment for lateral epicondylopathy of the elbow in 2002 [J Surg. 2015 ;24(Pt B):165–70. Epub 2015 Oct 9.].

“Although the strength of the supporting evidence is not strong, no method to treat lateral epicondylopathy is backed by studies with a high level of evidence. As the benefits largely exceed any potential harm, we recommend the use of radial or focused ESWT technologies when conventional rehabilitation treatment has failed.”

Greater Trochanteric Pain Syndrome

According to the authors, although the available evidence on ESWT in greater trochanteric pain syndrome is limited, RPW appears more effective than a home exercise program and local corticosteroid injection after short-term and mid-term follow-up (up to 15 months) of greater trochanteric pain syndrome.

Patellar Tendinopathy

Review of the literature shows that ESWT is safe and effective in the treatment of patellar tendinopathy. Current evidence supports the use of F-ESWT and RPW for patellar tendinopathy with moderate or low-intensity protocols, especially in patients attempting to avoid an invasive intervention.

Achilles Tendinopathy

Three systematic reviews and 1 review showed satisfactory evidence of the effectiveness of low-energy ESWT in insertional and noninsertional chronic Achilles tendinopathy after failure of conservative treatment and before considering surgery, especially in combination with eccentric loading.

Plantar Fasciitis

Several studies have compared F-ESWT with surgery, supporting the use of shockwave treatment because of its effectiveness and because patients can quickly resume full activitiesand athletes have a chance to continue sports activities.

Since 2010, the American College of Foot and Ankle Surgeons has recommended ESWT as a treatment of choice for plantar fasciitis with or without a plantar spur when nonoperative treatment has failed.

Bone Disorders

As some Level-I and II evidence has demonstrated that the efficacy of ESWT is comparable with that of surgery for the treatment of nonunions, and ESWT is practically free of adverse effects and more economic, it may progressively be considered as the first choice in the treatment of stable nonunions with a gap of <5 mm in long bones.

For bone treatment, the basic principles of acute fracture management should be implemented after F-ESWT (immobilization, casting, and weight-bearing restrictions).

ESWT seems to be an effective option in adult osteochondritis dissecans, but further studies are required to determine long-term results.

Economic and Administrative Considerations

When compared to the cost of surgery, shockwave treatment is a much more economical and involves a much shorter timeline for recovery.

“Dubs161 compared the efficacy and costs of ESWT with the usual treatments for CTS. In addition to demonstrating that ESWT was more efficacious, it also allowed for an average savings of US$2,000 per patient in comparison with alternative therapies.”

In conclusion, shockwave therapy is emerging as an effective therapy option for a variety of common conditions treated by musculoskeletal practitioners.  While it is currently difficult to obtain reimbursement for shockwave, sessions can become cash-based service offerings with package or per-visit pricing charged directly to patients.

Read the full text of the published paper here >>>

This post is part of a series on emerging rehab technologies.   In the coming weeks, our series will continue with the exploration of different shockwave therapy units and a comparison of their treatment capabilities and cost.