Ultrasound-Guided Dextrose Prolotherapy for Coccydynia: A Prospective Study

Evaluation of the Effectiveness of Dextrose Prolotherapy on Pain Severity and Functional Status in Patients With Coccydynia: A Prospective Study

Coccydynia is a musculoskeletal condition characterized by pain in the coccygeal region, particularly exacerbated by sitting, and is associated with impaired quality of life and functional limitation. Although various conservative and interventional treatment options are available, there remains a need for effective and safe alternative therapies, especially in treatment-resistant cases.

Prolotherapy is a regenerative treatment modality that aims to reduce pain and improve function by stimulating tissue repair, particularly in ligamentous structures. While there is increasing evidence supporting its effectiveness in mechanical musculoskeletal pain conditions, the literature regarding its use in coccydynia is limited.

The aim of this study is to evaluate the effect of dextrose prolotherapy on pain severity and functional status in patients diagnosed with coccydynia. This study is designed as a prospective, single-arm, open-label interventional study. Patients will receive 15% dextrose prolotherapy according to a standardized protocol. Pain severity will be assessed using the Visual Analog Scale (VAS), and functional status will be evaluated using the Dallas Pain Questionnaire before treatment and at 1 month after completion of the treatment.

This study aims to provide more comprehensive data on the effectiveness and safety of prolotherapy in coccydynia and to contribute to the currently limited evidence in the literature.

Study Overview

• Status: Recruiting
• Conditions: Coccydynia
• Intervention / Treatment: Procedure: Dextrose prolotherapy

Detailed Description

Coccydynia is a musculoskeletal disorder characterized by localized pain in the coccygeal region, typically exacerbated by sitting and postural changes, and associated with impaired quality of life and functional limitation. Although various conservative and interventional treatment modalities have been described, a subset of patients remains symptomatic despite standard therapies. Considering the potential role of ligamentous dysfunction, repetitive microtrauma, and coccygeal instability in the pathophysiology of coccydynia, regenerative treatment approaches such as prolotherapy may provide clinical benefit.

Prolotherapy is a regenerative injection therapy that involves the administration of an irritant solution, most commonly hypertonic dextrose, to stimulate the body's natural healing response. The proposed mechanism includes induction of a mild, controlled inflammatory response, leading to increased fibroblast proliferation, collagen synthesis, and subsequent strengthening of ligamentous and periarticular structures. In conditions associated with ligamentous laxity or enthesopathy, prolotherapy is thought to enhance tissue repair and restore biomechanical stability. Increasing evidence suggests that prolotherapy may reduce pain and improve function in various chronic musculoskeletal conditions, particularly those with a mechanical or ligamentous component. However, evidence regarding its effectiveness in coccydynia remains limited.

This study is designed as a prospective, single-arm, open-label interventional study to evaluate the effectiveness and safety of dextrose prolotherapy in patients with chronic coccydynia. Adult patients (≥18 years) with mechanical or idiopathic coccydynia persisting for at least 3 months and unresponsive to conservative treatment will be included. Patients with pregnancy, malignancy, active infection, bleeding diathesis, uncontrolled hypertension or diabetes mellitus, or contraindications to prolotherapy will be excluded.

All participants will receive prolotherapy using a 15% dextrose solution prepared under sterile conditions. Injections will be performed under ultrasound (USG) guidance to ensure precise anatomical localization and to enhance procedural safety. During the procedure, the sacral hiatus, sacrococcygeal ligament, and coccygeal bony structures will be visualized, and bone landmarks will be used as references. The fibrous ligamentous attachments in the coccygeal and sacrococcygeal region will be targeted, and injections will be administered to 3-4 periosteal insertion points using a 27G needle, with a maximum of 0.5 mL per site and a total volume not exceeding 2-2.5 mL per session. The procedure will be repeated at 3-week intervals, with a total of 3 to 6 sessions depending on clinical response.

The primary outcome measure will be the change in pain severity assessed by the Visual Analog Scale (VAS). The secondary outcome measure will be the change in functional status evaluated using the Dallas Pain Questionnaire. Outcome assessments will be performed at baseline (pre-treatment) and at 1 month after completion of the treatment protocol.

Sample size was calculated based on a power analysis (α=0.05, power=0.80), which indicated that a minimum of 25 patients would be required. Considering a potential 15% dropout rate, a total of 30 patients will be enrolled.

Safety will be assessed by monitoring and recording any adverse events throughout the study period. All participants will be followed prospectively, and changes in clinical parameters will be analyzed to determine the effectiveness of the intervention.

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Merve Dikici Yagli, M.D; Phone Number: +905387192098; Email: mervedikici1992@gmail.com
• Study Contact Backup: Name: Yunus Emrah Kosut, M.D; Phone Number: +905355540389; Email: kosutyunus@gmail.com

Study Locations

• Turkey (Türkiye)
  • Istanbul, Turkey (Türkiye)
    • Recruiting
    • Gaziosmanpasa Research and Education Hospital
    • Contact: Merve Dikici Yaglı, M.D; Phone Number: +905387192098; Email: mervedikici1992@gmail.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age between 18 and 75 years
• Pain persisting for ≥3 months and refractory to conservative treatment
• Coccydynia of mechanical or idiopathic origin

Exclusion Criteria:

• Age <18 years or >75 years
• Pregnancy
• Allergy to the proliferant solution
• Active infection
• Use of anticoagulant medications
• Presence of malignancy
• Local abscess
• Hemorrhagic diathesis
• Certain types of septic arthritis
• Parafunctional habits

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Dextrose Prolotherapy; Participants will receive ultrasound-guided dextrose prolotherapy according to a standardized treatment protocol.

Procedure: Dextrose prolotherapy; All participants will receive prolotherapy using a 15% dextrose solution prepared under sterile conditions. Injections will be performed under ultrasound (USG) guidance to ensure precise anatomical localization and to enhance procedural safety. During the procedure, the sacral hiatus, sacrococcygeal ligament, and coccygeal bony structures will be visualized, and bone landmarks will be used as references. The fibrous ligamentous attachments in the coccygeal and sacrococcygeal region will be targeted, and injections will be administered to 3-4 periosteal insertion points using a 27G needle, with a maximum of 0.5 mL per site and a total volume not exceeding 2-2.5 mL per session. The procedure will be repeated at 3-week intervals, with a total of 3 to 6 sessions depending on clinical response.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Visual Analog Scale	Visual Analog Scale for Pain (VAS): Change in pain intensity assessed using the Visual Analog Scale (VAS).The VAS is a 10-cm horizontal scale ranging from 0 (no pain) to 10 (worst imaginable pain).Higher scores indicate greater pain intensity, and a reduction in VAS score represents clinical improvement.	Baseline and 1 month after completion of treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dallas Pain Questionnaire (DPQ)	The Dallas Pain Questionnaire (DPQ) is a validated instrument that evaluates the impact of chronic pain on functional status across four domains: daily activities, work and leisure activities, anxiety/depression, and social interest. Scores range from 0 to 100, with higher scores indicating greater functional limitation and a higher degree of pain-related impairment, whereas lower scores reflect better functional capacity and lower levels of impairment.	Baseline and 1 month after completion of treatment

Collaborators and Investigators

• Sponsor: Gaziosmanpasa Research and Education Hospital
• Investigators: Principal Investigator: Merve Dikici Yagli, M.D, Gaziosmanpasa Research and Education Hospital

Publications and helpful links

General Publications

• Mociu SI, Nedelcu AD, Lupu AA, Uzun AB, Iliescu DM, Ionescu EV, Iliescu MG. Prolotherapy as a Regenerative Treatment in the Management of Chronic Low Back Pain: A Systematic Review. Medicina (Kaunas). 2025 Sep 2;61(9):1588. doi: 10.3390/medicina61091588.
• Benditz A, Thoma R. Coccygodynia-Diagnosis and Treatment. Dtsch Arztebl Int. 2025 Nov 14;122(23):638-644. doi: 10.3238/arztebl.m2025.0154.
• Khan SA, Kumar A, Varshney MK, Trikha V, Yadav CS. Dextrose prolotherapy for recalcitrant coccygodynia. J Orthop Surg (Hong Kong). 2008 Apr;16(1):27-9. doi: 10.1177/230949900801600107.

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2026
• Primary Completion (Estimated): June 15, 2026
• Study Completion (Estimated): June 15, 2026

Study Registration Dates

• First Submitted: April 27, 2026
• First Submitted That Met QC Criteria: April 27, 2026
• First Posted (Actual): May 4, 2026

Study Record Updates

• Last Update Posted (Actual): May 4, 2026
• Last Update Submitted That Met QC Criteria: April 27, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Ultrasound-Guided Injection; Coccydynia; Dextrose Prolotherapy
• Other Study ID Numbers: 14

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared due to institutional data protection policies and the absence of participant consent for data sharing beyond the scope of the current study.

Drug and device information, study documents

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