Oct. 10, 2025
Within the United States, the use of high-energy acoustic waves as a tool for medical procedures can be traced back to the early 1980s when urologists first performed lithotripsy to pulverize kidney stones. Decades later, specific devices for orthopedic conditions emerged as a nonsurgical, therapeutic treatment for a variety of musculoskeletal conditions. Additionally, there is emerging evidence for the use in neurologic disorders, such as reducing spasticity.
Focused shockwave (FSW) and radial pressure wave (RPW) therapies involve the transcutaneous application of acoustic waves, which leads to mechanotransduction at the cellular level. These changes can then stimulate cell proliferation, migration, alteration in pain pathways, increased neovascularization and osteoprogenitor differentiation. In this article, Joshua M. Romero, M.D., presents an update on FSW and RPW describing their physical properties, biologic effects, benefits, indications, contraindications, potential side effects and complications. Dr. Romero is a physiatrist and sports medicine specialist at Mayo Clinic's Sports Medicine Center in Rochester, Minnesota.
Device types
Radial pressure wave treatment
Radial devices produce radial pressure waves via a projectile accelerated toward the applicator. As the projectile strikes the applicator, a radial pressure wave is produced. As the wave propagates through tissue in a radial direction, the energy dissipates. Given that the highest energy for radial pressure wave is near the applicator tip, these devices are effective for treating tendinopathies and fasciopathies.
Historically, FSW and RPW were referred to as extracorporeal shockwave therapy (ESWT). However, only FSW generates a true shockwave, which has different physical properties than the waveform of a radial pressure wave. Therefore, the use of "shockwave" should only be reserved for FSW, and radial devices should be referred to as RPW. Both are administered through hand-held devices with applicator tips. FSW and RPW can be used separately or in combination, depending on the condition being treated.
Focused shockwaves are produced by electrohydraulic, electromagnetic and piezoelectric devices to generate acoustic waves with high peak pressure, short duration and wide frequency range. FSW generates maximal force at a particular depth, based on the device used, applicator tip and tissue density of application. FSW can be used to treat tendinopathies and fasciopathies but also bone-related conditions, given its ability to promote osteoprogenitor differentiation.
Radial devices produce radial pressure waves via a projectile accelerated toward the applicator. As the projectile strikes the applicator, a radial pressure wave is produced. This wave reaches its maximal energy near the applicator tip. As the wave propagates through tissue in a radial direction, the energy dissipates. Based on the waveform produced by radial devices, they are most effective for tendinopathies and fasciopathies.
Biologic effects
Dr. Romero notes that the exact mechanisms by which FSW and RPW work are still not fully understood. However, multiple studies have highlighted several biologic effects in both soft tissue and bone-related conditions.
"It's thought that the transmission of acoustic waves leads to cellular mechanotransduction, causing a cellular shift that leads to secondary cell signaling, promoting cellular migration and proliferation. It can also cause increased vascularity and act on pain pathways to reduce pain via increasing local pain-inhibiting substances and nociceptor hyperstimulation," says Dr. Romero.
Multiple animal studies have described biologic effects, including neovascularization at the tendon-bone junction, proliferation of tenocytes, osteoprogenitor differentiation, and amplification of growth factors for protein and collagen synthesis.
"All of these can help promote tissue remodeling. Patients who have had FSW or RPW typically report decreased pain initially after treatment because the C-fibers have really been overwhelmed. And they can also get dilution of substance P as well. More-durable improvements in pain and function can take up to 8 to 12 weeks in some cases. We are now also asking if FSW can actually lead to recruitment of progenitor cells. There's still some work to be done in this area, but it's certainly an interesting question to consider."
Treatment benefits
Dr. Romero is enthusiastic when describing the benefits associated with FSW and RPW. "These treatments can lead to pain relief and augment tissue remodeling in the treatment area. They are noninvasive, and there's minimal to no activity restrictions required after the procedure," says Dr. Romero. "This last benefit is a very important point for active individuals. The procedures are also cost-efficient, compared with surgery and other more-invasive treatments, and they have minimal associated adverse effects."
Current indications and contraindications
Dr. Romero explains that as more clinical trials studying FSW and RPW share findings, the list of recommended indications may expand, including combination therapy with other treatments such as orthobiobologics. Currently, although the device is approved by the Food and Drug Administration for treatment of plantar fasciopathy, FSW and RPW are still not covered by most insurance plans.
For updated guidance, Dr. Romero advises consulting the consensus statement provided by the International Society for Medical Shockwave Treatment (ISMST).
Current ISMST indications:
- Chronic tendinopathies, including calcifying tendinopathy of the shoulder, lateral epicondylopathy of the elbow, greater trochanter pain syndrome, patellar tendinopathy, Achilles tendinopathy, and plantar fasciitis with or without heel spur.
- Bone pathologies, including delayed bone healing, bone nonunion, stress fracture, avascular bone necrosis without articular derangement, and osteochondritis dissecans without articular derangement.
- Skin pathologies, including delayed or nonhealing wounds, skin ulcers, and noncircumferential burn wounds.
Dr. Romero adds that there is also mounting evidence supporting the use of shockwave to treat spasticity, with some studies demonstrating that it is not inferior to botulinum toxin treatments.
Current ISMST contraindications:
- For treatment using radial and focused waves with low energy — a malignant tumor or fetus in the treatment area.
- For treatment using high-energy focused waves — severe coagulopathy or the presence of any of the following in the treatment area: a fetus, lung tissue, malignant tumor, epiphyseal plate, brain or spine.
Potential side-effects and complications
Documented side effects include skin erythema, mild skin bruising and pain at the application site. Dr. Romero notes that there's less consensus on associated complications, but these can include hematoma formation, nerve irritation, edema and a theoretical risk of tendon rupture.
"In general, we're seeing an increasing use of shockwave treatment," explains Dr. Romero. "It's a safe and effective treatment. It's a noninvasive alternative to injections as well as surgery. There's an expanding clinical evidence base supporting its use. And, quite frankly, a lot of patients are preferring noninvasive treatments and asking about it."
Additional considerations
While the evolution of these treatments and their expanding uses are encouraging, Dr. Romero cautions that it's important to understand the limitations of these treatments and how to properly administer them. In the next issue of this newsletter, Dr. Romero will share more details about Mayo Clinic's experience using FSW and RPW, including peri- and postprocedural considerations, administration parameters, approaches to patient counseling and other information to help optimize treatment results.
For more information
ISMST Consensus statement on ESWT indications and contraindications.
Refer a patient to Mayo Clinic.