Extracorporeal Shockwave Therapy and Platelet-Rich Plasma for Midportion Achilles Tendinopathy

A Randomized Controlled Trial Evaluating the Influence of Physical Therapy, Shockwave Therapy, Platelet Rich Plasma or Combined Treatment in the Management of Midportion Achilles Tendinopathy

Midportion Achilles tendinopathy is a common cause of pain and functional limitation in both athletes and the general population. Progressive tendon loading programs are considered first-line treatment but do not lead to satisfactory outcomes in all patients. Extracorporeal shockwave therapy (ESWT) and platelet-rich plasma (PRP) injections are commonly used interventions for refractory symptoms, yet evidence supporting their combined use is limited particularly in treating Achilles tendon disorders.

This randomized controlled trial will evaluate the effectiveness of a standardized exercise program alone or in combination with PRP injection, ESWT, or both therapies in active adults with midportion Achilles tendinopathy. Participants will be randomized to one of four treatment groups and followed for six months. The primary outcome will assess changes in Achilles tendon symptoms and function using the Victorian Institute of Sport Assessment-Achilles (VISA-A) score. Secondary outcomes will include patient-reported outcomes, physical function testing, ultrasound tendon structure measures, and gait biomechanics.

Study Overview

• Status: Not yet recruiting
• Conditions: Achilles Tendon Pain; Achilles Injuries Tendon; Achilles Tendonitis; Achilles Tendinitis, Right Leg; Achilles Tendinitis, Left Leg; Achilles Tendinopathy (AT)
• Intervention / Treatment: Device: Sham PRP; Device: Sham ESWT; Device: Platelet Rich Plasma; Device: Extracorporeal Shockwave Therapy

Detailed Description

Midportion Achilles tendinopathy (Mid-AT) is characterized by pain, stiffness, and impaired function resulting from a failed tendon healing response. Progressive loading exercise programs such as the Silbernagel protocol represent the current standard treatment and provide meaningful improvement for many individuals. However, approximately 40% of patients continue to experience persistent symptoms despite rehabilitation.

Extracorporeal shockwave therapy (ESWT) and platelet-rich plasma (PRP) injections are increasingly used in clinical practice to address refractory symptoms. ESWT is proposed to stimulate tissue healing through mechanotransduction and has demonstrated improved outcomes when combined with exercise therapy in some studies. PRP contains concentrated autologous growth factors that may enhance tendon healing through stimulation of extracellular matrix production, angiogenesis, and collagen synthesis.

Despite increasing clinical use, there remains limited evidence evaluating the comparative or combined effects of PRP and ESWT in the treatment of Achilles tendinopathy. Furthermore, few trials have evaluated these therapies within a standardized rehabilitation framework.

The purpose of this randomized controlled trial is to evaluate the effectiveness of exercise therapy alone compared with exercise therapy combined with PRP injection, ESWT, or both interventions in individuals with chronic midportion Achilles tendinopathy. Participants will be randomized to one of four treatment groups: exercise with sham procedures (control), exercise plus PRP injection, exercise plus ESWT, or exercise combined with PRP and ESWT. Participants will be followed for six months to evaluate patient-reported outcomes, tendon structure using ultrasound, physical function testing, and gait biomechanics. This study aims to determine whether PRP, ESWT, or the combination of both treatments provide superior functional recovery compared with exercise-based rehabilitation alone.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Sydney Karnovsky, MD; Phone Number: (862) 216-8050; Email: skarnovsky@mgb.org

Study Locations

• United States
  • Massachusetts
    • Cambridge, Massachusetts, United States, 02138
      • Spaulding Cambridge Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age 18-65 years
• Diagnosis of unilateral midportion Achilles tendinopathy
• Symptoms present for more than 3 months
• VISA-A score <80 at baseline
• Pre-injury physical activity level ≥3 on the Physical Activity Scale
• Ability to participate in rehabilitation program

Exclusion Criteria:

• Symptoms present for less than 3 months
• Prior PRP injection or ESWT treatment to the Achilles tendon within 3 months
• Other lower extremity musculoskeletal injury affecting function
• Symptomatic arthritis affecting the ankle or foot
• Rheumatologic disease or connective tissue disorder
• Coagulopathy or anticoagulant therapy affecting platelet function
• Neuropathy affecting pain perception
• Known cardiac condition contraindicating treatment
• Poorly controlled diabetes (HbA1c >9.0)
• Pregnancy

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Sham Comparator: Arm 1 - Control Exercise Therapy + Sham PRP + Sham Shockwave; A sham PRP injection will be performed where the needle breaks the skin but does not fenestrate the tendon. The sham ESWT will include radial pressure waves and focused shockwaves delivered without the device turned on to deliver energy and audio recording. Standard of care exercise program will be prescribed to participants with four stages to be performed during the study.	Device: Sham PRP; A needle will be inserted but no injection will occur around the Achilles tendon; Device: Sham ESWT; Both focused shockwave and radial pressure wave will be in contact with the skin, but the devices will not be active to deliver energy. An audio recording will provide noises similar to the machines operating.
Experimental: Arm 2 - Exercise Therapy + Platelet-Rich Plasma (PRP) + Sham Shockwave; PRP will be delivered around the tendon, sham ESWT will be issued. Standard of care exercise program will be prescribed to participants with four stages to be performed during the study.	Device: Sham ESWT; Both focused shockwave and radial pressure wave will be in contact with the skin, but the devices will not be active to deliver energy. An audio recording will provide noises similar to the machines operating.; Device: Platelet Rich Plasma; Participants randomized to PRP will receive a single ultrasound-guided injection of approximately 3 mL of neutrophil-poor platelet-rich plasma derived from autologous blood. Blood will be processed to concentrate platelets and the PRP will be injected adjacent to the Achilles tendon at the site of maximal pain.
Experimental: Arm 3 - Exercise Therapy + Extracorporeal Shockwave Therapy (ESWT) + Sham PRP; Sham PRP will be delivered. Three sessions of ESWT will be delivered to the Achilles tendon. Standard of care exercise program will be prescribed to participants with four stages to be performed during the study.	Device: Sham PRP; A needle will be inserted but no injection will occur around the Achilles tendon; Device: Extracorporeal Shockwave Therapy; Participants randomized to ESWT will receive three weekly treatment sessions. Focused shockwave therapy will deliver approximately 2000 shocks with gradual energy escalation, followed by radial shockwave therapy delivering approximately 3000 pulses to the Achilles tendon and 3000 pulses to surrounding musculature.
Experimental: Arm 4 - Exercise Therapy + Platelet-Rich Plasma + Extracorporeal Shockwave Therapy; PRP will be administered followed by three sessions of ESWT. Standard of care exercise program will be prescribed to participants with four stages to be performed during the study.	Device: Platelet Rich Plasma; Participants randomized to PRP will receive a single ultrasound-guided injection of approximately 3 mL of neutrophil-poor platelet-rich plasma derived from autologous blood. Blood will be processed to concentrate platelets and the PRP will be injected adjacent to the Achilles tendon at the site of maximal pain.; Device: Extracorporeal Shockwave Therapy; Participants randomized to ESWT will receive three weekly treatment sessions. Focused shockwave therapy will deliver approximately 2000 shocks with gradual energy escalation, followed by radial shockwave therapy delivering approximately 3000 pulses to the Achilles tendon and 3000 pulses to surrounding musculature.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Victorian Institute of Sport Assessment-Achilles (VISA-A)	The VISA-A is an eight item questionnaire measures Achilles tendon pain and function, with scores ranging from 0 to 100 (higher scores indicating better function).	baseline, 8 weeks, 4 months, 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
PROMIS-29 Patient Reported Outcomes	Change in PROMIS-29 domain scores evaluating physical function, pain interference, fatigue, sleep disturbance, anxiety, depression, and social participation.	Baseline, 8 weeks, 4 months, 6 months
University of Wisconsin Running Injury and Recovery Index (UWRI)	Running-specific recovery and functional ability measure for participants who run regularly.	baseline, 8 weeks, 4 months, 6 months
Ultrasound Tendon Cross-Sectional Area	Changes in Achilles tendon cross-sectional area measured by ultrasound at the site of maximal tendon thickness.	baseline, 6 months
Heel Rise Test Endurance	Total number of single-leg heel raises performed until fatigue or inability to maintain pace or same height.	baseline, 6 months
Hop Test Pain	Pain rating following completion of a standardized single-leg hop test of 20 repetitions.	baseline, 6 months
Gait Biomechanics	Changes in lower extremity biomechanics and symmetry during walking and running assessed using motion capture and instrumented treadmill analysis in those who elect to complete biomechanical assessment.	baseline, 6 months

Collaborators and Investigators

• Sponsor: Spaulding Rehabilitation Hospital
• Collaborators: Storz Medical AG; Foundation for Physical Medicine and Rehabilitation
• Investigators: Principal Investigator: Adam S. Tenforde, MD, Spaulding Rehabiltaition Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): November 30, 2027
• Study Completion (Estimated): May 30, 2028

Study Registration Dates

• First Submitted: March 15, 2026
• First Submitted That Met QC Criteria: March 15, 2026
• First Posted (Actual): March 19, 2026

Study Record Updates

• Last Update Posted (Actual): May 13, 2026
• Last Update Submitted That Met QC Criteria: May 8, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: rehabilitation; platelet rich plasma; PRP; extracorporeal shockwave; focus shockwave; radial pressure waves
• Additional Relevant MeSH Terms: Therapeutics; Physical Therapy Modalities; Rehabilitation; Ultrasonic Therapy; Diathermy; Hyperthermia, Induced; Extracorporeal Shockwave Therapy
• Other Study ID Numbers: 2025P002308

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: No identifiable information will be shared outside Mass General Brigham. We will consider publishing a limited deidentified data set at time of publication of our findings.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No