Extracorporeal Shockwave Therapy: Building the Evidence in Musculoskeletal Medicine
"Walk it off" is a common refrain heard after a seemingly minor musculoskeletal injury during a sporting event. When those minor injuries turn into chronic conditions like knee tendinopathy or plantar fasciitis, however, athletes and active individuals are wise to seek the services of a sports medicine physician like Adam Tenforde, MD, at Spaulding Rehabilitation.
A practicing physician and an associate professor in the Department of Physical Medicine and Rehabilitation at Harvard Medical School, Dr. Tenforde is not only a doctor but also a former professional runner. He provides a full range of treatments to help athletes and active individuals safely and quickly return to the sports and activities they love.
One of the newer treatments Dr. Tenforde offers is extracorporeal shockwave therapy (ESWT), which creates energy using pressure waves and sound waves that have proposed effects on reducing pain and improving tissue function. As the director of Shockwave Medicine at Mass General Brigham, he has been collecting six years of patient-reported outcome data to establish evidence for the safe and effective use of ESWT as part of a comprehensive rehabilitation program.
According to Dr. Tenforde, ESWT represents an alternative to traditional treatments. Often patients have pain despite activity modification and the use of nonsteroidal anti-inflammatory medications (the ongoing use of which has been tied to an increased risk of cardiovascular events in many adults) as well as use of corticosteroids and anesthetic medications (which can potentially cause localized or systemic toxicity).
"The field of sports medicine is at an exciting stage of discovering how to use shockwave in clinical practice to treat a variety of musculoskeletal injuries," he says. "There's a level of variability in how the technology is applied and how patients respond. That's why Mass General Brigham is committed to understanding this technology and other innovative strategies by incorporating patient-reported outcome measures to understand the individual patient as well as condition-specific response."
From Urology to Sports Medicine: Extending the Use of ESWT
ESWT was first introduced into clinical practice in the early 1980s for urological conditions, primarily to manage symptomatic kidney stones. Soon thereafter, it was studied in orthopedics — initially for use in fracture healing but more commonly for treating upper and lower extremity tendinopathies, fasciopathies, and soft tissue conditions.
In a review of ESWT studies published in PM&R in 2018, Dr. Tenforde and colleagues suggested that the technology is a "generally well-tolerated treatment strategy for multiple musculoskeletal conditions commonly seen in clinical practice." The authors noted that despite three decades of ESWT research, few standardized protocols exist for treating musculoskeletal conditions. They pointed to differences in treatment protocols, activity restriction, adjuvant therapy, outcome measure definition, and other variables.
Dr. Tenforde addressed many of these issues when he and colleagues published suggested best practices for clinical application and training in PM&R in 2022. Recommendations include:
- The use of clinical focusing without anesthetics for the treatment of tendinopathies, fasciopathy, and soft tissue pathologies
- The use of high-energy application for bone stress injuries, delayed union, and avascular necrosis
- Combining focused shockwave therapy and radial shockwave therapy for treatment of certain musculoskeletal conditions
- Proper ergonomic techniques for physicians and technicians performing shockwave
Building ESWT Into Resident Education
The best practices guidance published by Dr. Tenforde and colleagues includes a recommendation to incorporate ESWT into didactic and clinical components of residency and fellowship training. They present a framework for an ESWT curriculum based on existing standards, milestones, and competencies from musculoskeletal ultrasound curricula supported by the Accreditation Council for Graduate Medical Education, American Board of Physical Medicine and Rehabilitation, and American Medical Society for Sports Medicine.
"As the official teaching partner of the Harvard Medical School of Physical Medicine and Rehabilitation, teaching is one of our core missions at Spaulding Rehabilitation," Dr. Tenforde says. "It is our privilege and duty to educate the next generation to be more effective physicians and provide the most effective patient care possible. Importantly, we as educators need to engage our trainees in responsible review of patient outcome measures so that they know how to apply ESWT in clinical practice to provide measurable effects."
Combining ESWT and Cell-based Therapy
The goal of optimizing patient outcomes for ESWT has led Dr. Tenforde in the direction of combining it with orthobiologic sports medicine treatment using platelet-rich plasma (PRP). PRP is a concentration of the patient's own platelets. Platelets contain proteins that are growth factors that are important in the healing of injuries and the reduction of chronic inflammation.
Dr. Tenforde pointed to two recent cases published in the German Journal of Sports Medicine, in which patients (a 69-year-old female and 73-year-old male, both runners) completed courses of ESWT along with physical therapy using a foot core physical therapy program. In these cases, the injury to the plantar fascia was more advanced and required a combined approach.
Post-treatment, the patients experienced functional improvement but persistent pain that limited goals to run. The addition of a single leukocyte-poor PRP injection allowed both to successfully return to running.
"Patients have variability on treatment response, including with ESWT," Dr. Tenforde says. "In the cases we described, the physical exam and imaging suggested the plantar fasciitis was still injured and led to exploring PRP as a treatment option. While not well-studied, the combination of the ESWT and PRP has been proposed to create a synergistic effect which could promote tissue healing and represent a new strategy for patients with pain that is refractory to the current standard of care."
Dr. Tenforde says cases like these, as well as evidence developed through clinical trials, will help physicians optimize ESWT treatment for individual patients and advocate for insurance reimbursement for treatments labeled as "experimental."
"Our goal is to provide targeted treatments using ESWT and other therapies which help optimize benefits and minimize risks," he says. "We're also working on developing post-procedure and physical therapy protocols to help guide patients through the experience. All this work at Mass General Brigham is being done in close collaboration with our colleagues across primary care sports medicine, orthopedic surgery, and rheumatology so that we can help patients make informed decisions based on the best evidence."