Ultrasound-Guided Extracorporeal Shock Wave Therapy for Calcific Tendinitis (ESWT)

Effectiveness of Ultrasound-Guided Extracorporeal Shock Wave Therapy for Calcific Tendinitis of the Shoulder: A Randomized Double-Blind Controlled Trial

Calcific tendinitis of the shoulder is a debilitating musculoskeletal condition that significantly impacts the working-age population, typically those between 30 and 60 years of age. Accounting for approximately 7- 17% of shoulder pain complaints, it is characterized by the pathological deposition of calcium hydroxyapatite crystals within the rotator cuff tendons, most notably the supraspinatus. The progression of the disease, particularly during the resorptive phase described in Uhthoff's cycle, is associated with a dramatic increase in intratendinous pressure and severe inflammatory pain, leading to substantial functional impairment and socioeconomic burden. While Extracorporeal Shock Wave Therapy (ESWT) is a well established non-invasive modality known to promote calcific resorption via cavitation effects and mechanotransduction-induced neovascularization, its clinical efficacy remains highly variable across current literature, with success rates ranging widely from 47% to 87%. This inconsistency is largely attributed to the limitations inherent in conventional "blind" or landmark-based targeting techniques. Given that calcific deposits are often small, deeply situated, or obscured by the acromion, palpation-guided targeting is frequently unreliable, resulting in suboptimal energy delivery to the pathology and potential collateral damage to surrounding healthy tissues. This one-year research project aims to evaluate the superior efficacy of "Real-time Ultrasound-Guided" ESWT compared to conventional methods. The investigators propose a prospective, randomized, double-blind, controlled trial (RCT) that will recruit 60 patients with confirmed calcific tendinitis. Participants will be stratified by Gärtner classification (Type I-III) to ensure balanced morphological distribution and then randomized into either an experimental group receiving Ultrasound-Guided Focused ESWT or a control group receiving Landmark-based/Sham ESWT. The study incorporates rigorous methodology, including a priori power analysis for sample size estimation, strict allocation concealment, and assessor blinding. Outcomes will be assessed at baseline, 4, and 12 weeks post-treatment. Primary outcomes include the Constant-Murley Score (CMS) and Visual Analog Scale (VAS), while secondary outcomes involve quantitative ultrasound analysis using ImageJ software to measure the reduction in calcific deposit volume and assess tendon integrity. The investigators hypothesize that the integration of realtime ultrasound guidance will significantly enhance therapeutic precision, leading to higher rates of calcific resorption and functional recovery. The findings are expected to provide high-level evidence to standardize ESWT protocols, thereby advancing the implementation of precision medicine in the field of physical and rehabilitation medicine.

Study Overview

• Status: Recruiting
• Conditions: Calcific Tendinitis of Shoulder
• Intervention / Treatment: Procedure: Ultrasound guide localization; Procedure: Palpation localization

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shih-Wei Huang, MD; Phone Number: +886970747556; Email: shihwei@tmu.edu.tw

Study Locations

• Taiwan
  • Taipei
    • Taipei, Taipei, Taiwan, 116
      • Recruiting
      • Wan Fang Hospital, Taipei Medical University
      • Contact: Shih-Wei Huang; Phone Number: 0970747556; Email: shihwei@tmu.edu.tw

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age between 20 and 70 years
• Unilateral calcific tendinitis of the shoulder confirmed by clinical physical examination, including a positive Neer's impingement test
• Symptom duration of more than 3 months
• Imaging (radiography and/or high-resolution ultrasound) demonstrating a calcific deposit within a rotator cuff tendon with a maximal diameter greater than 5 mm
• Baseline self-reported pain intensity greater than 4 on the Visual Analog Scale (VAS, 0-10)
• Willing and able to provide written informed consent

Exclusion Criteria:

• Concomitant full-thickness rotator cuff tear
• History of fracture or surgery involving the ipsilateral shoulder
• Coagulopathy, or anticoagulant therapy that cannot be safely discontinued
• Pregnancy or breastfeeding
• Malignancy, particularly involving or adjacent to the shoulder region
• Local infection or skin lesion at the intended treatment site
• Injection therapy to the ipsilateral shoulder within the preceding 6 weeks
• Any other condition that, in the judgment of the investigator, makes the participant unsuitable for participation in the trial

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Ultrasound localization ESWT; Ultrasound image guided the depth and location of calcification point, Perform ESWT for calcific tendonitis of shoulder	Procedure: Ultrasound guide localization; Use ultrasound guided localization of calcific tendonitis of shoulder and then perform Extracorporeal Shock Wave Therapy, ESWT 0.12 to 0.25 mJ/mm 6000 times
Active Comparator: Palpation localization ESWT; Palpation and depends the feedback of participants localization of ESWT points	Procedure: Palpation localization; Use palpation localization of calcific tendonitis of shoulder and then perform Extracorporeal Shock Wave Therapy, ESWT 0.12 to 0.25 mJ/mm 6000 times

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Constant-Murley Score (CMS)	The Constant-Murley Score is a clinician-administered instrument assessing shoulder function across four domains: pain (15 points), activities of daily living (20 points), range of motion (40 points), and strength (25 points), for a total score of 0-100. Higher scores indicate better shoulder function. The measure compares real-time high-resolution ultrasound-guided focused ESWT (experimental) with X-ray plus palpation-guided focused ESWT (control) for calcific tendinitis of the shoulder. Assessed at baseline, Week 4, and Week 12; change from baseline is reported.	Baseline, Week 4, and Week 12 after the start of treatment (primary endpoint at Week 12)
Change in Pain Visual Analog Scale (VAS)	Pain intensity is self-reported on a 0-10 Visual Analog Scale, where 0 = no pain and 10 = worst imaginable pain. Ratings are collected for pain at rest, pain with activity, night pain, and average pain over the past week. Higher scores indicate greater pain. Change from baseline is compared between the ultrasound-guided ESWT and landmark (X-ray + palpation)-guided ESWT groups. Assessed at baseline, Week 4, and Week 12.	Baseline, Week 4, and Week 12 after the start of treatment (primary endpoint at Week 12)
Change from Baseline in Shoulder Pain and Disability Index (SPADI)	Patient-reported questionnaire comprising a 5-item pain subscale and an 8-item disability subscale, each item scored 0-10. Subscale and total scores are expressed as percentages (0-100%), with higher scores indicating greater pain and disability.	Baseline, Week 4, Week 12

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Calcific Deposit Resorption Rate	Calcific deposit dimensions (long axis, short axis, area, and estimated volume) are quantified from ultrasound images using ImageJ software. Percentage volume reduction from baseline is calculated. Resorption is additionally categorized as complete, partial (>50%), partial (<50%), unchanged, or increased.	Baseline, Week 4, Week 12
Change from Baseline in Shoulder Range of Motion (ROM)	Active and passive range of motion measured in degrees with a goniometer for forward flexion, abduction, external rotation at 90° abduction, and internal rotation at 90° abduction.	Baseline, Week 4, Week 12
Tendon Structural Integrity on Ultrasound	Supraspinatus (or affected) tendon integrity graded on high-resolution ultrasound as intact, partial-thickness tear, or full-thickness tear. Tendon thickness is recorded in millimeters.	Baseline, Week 4, Week 12
Patient Global Impression of Change (PGIC)	Single-item 7-point scale ranging from 1 (very much improved) to 7 (very much worse), capturing the participant's overall perceived change since starting treatment.	Week 4, Week 12

Collaborators and Investigators

• Sponsor: Taipei Medical University WanFang Hospital

Study record dates

Study Major Dates

• Study Start (Actual): June 30, 2026
• Primary Completion (Estimated): April 30, 2027
• Study Completion (Estimated): August 31, 2027

Study Registration Dates

• First Submitted: August 5, 2026
• First Submitted That Met QC Criteria: August 5, 2026
• First Posted (Actual): August 10, 2026

Study Record Updates

• Last Update Posted (Actual): August 12, 2026
• Last Update Submitted That Met QC Criteria: August 9, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: ultrasound; shoulder; ESWT; Calcific tendonitis
• Additional Relevant MeSH Terms: Crystal Arthropathies; Musculoskeletal Diseases; Arthritis; Joint Diseases; Chondrocalcinosis; Rotator Cuff Tear Arthropathy
• Other Study ID Numbers: N202604139

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data (IPD) that underlie the results reported in the publication (including text, tables, figures, and appendices) will be shared. This includes baseline characteristics, intervention adherence, and primary and secondary outcome measures. Additionally, the study protocol, statistical analysis plan (SAP), and data dictionary will be made available.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No