Ganglion Impar vs Coccygeal Nerve Radiofrequency Ablation in Chronic Coccydynia

Comparison of Fluoroscopy-Guided Ganglion Impar and Ultrasound-Guided Coccygeal Nerve Radiofrequency Ablation in Patients With Chronic Coccydynia: A Prospective Randomized Study

Chronic coccydynia is a condition characterized by persistent pain in the coccyx region that significantly affects daily activities and quality of life. When conservative treatments fail, interventional pain procedures such as radiofrequency ablation may be considered.

This single-center, prospective, randomized study compared two radiofrequency ablation techniques used in the treatment of chronic coccydynia: fluoroscopy-guided ganglion impar radiofrequency ablation and ultrasound-guided coccygeal nerve radiofrequency ablation. Adult patients with chronic coccydynia who did not respond to medical treatment were randomly assigned to receive one of these two interventions. Pain intensity and functional disability were evaluated using standardized assessment tools before the procedure and during follow-up visits at 3 weeks and 3 months after treatment. The primary objective was to compare pain relief between the two techniques at 3 months. Secondary objectives included evaluation of functional improvement and procedure-related complications. The results of this study provide comparative information on the effectiveness and safety of these two commonly used radiofrequency techniques and may help guide clinicians in selecting appropriate interventional treatments for patients with chronic coccydynia.

Study Overview

• Status: Completed
• Conditions: Chronic Coccydynia
• Intervention / Treatment: Procedure: Ganglion impar radiofrequency ablation; Procedure: Coccygeal nerve radiofrequency ablation

Detailed Description

This study was designed as a single-center, prospective, randomized clinical trial to compare two radiofrequency ablation techniques used for the treatment of chronic coccydynia: fluoroscopy-guided ganglion impar thermal radiofrequency ablation and ultrasound-guided coccygeal nerve thermal radiofrequency ablation.Adult patients with chronic coccydynia persisting for more than three months and refractory to conservative medical management were evaluated for eligibility. Following informed consent, eligible participants were randomly assigned in a 1:1 ratio to undergo either ganglion impar radiofrequency ablation or coccygeal nerve radiofrequency ablation. Randomization was performed prior to the intervention.All procedures were conducted under standard sterile conditions by experienced pain physicians. Ganglion impar radiofrequency ablation was performed under fluoroscopic guidance, while coccygeal nerve radiofrequency ablation was performed under ultrasound guidance. Both interventions followed established clinical protocols routinely used in interventional pain practice. Pain intensity was assessed using the Numeric Rating Scale (NRS), and functional status was evaluated using the modified Oswestry Disability Index (MODI). Assessments were conducted at baseline prior to the procedure and during follow-up visits at 3 weeks and 3 months after treatment. Adverse events and procedure-related complications were monitored and recorded throughout the follow-up period. The primary outcome measure was the proportion of patients achieving at least a 50% reduction in NRS score at 3 months compared with baseline. Secondary outcome measures included changes in MODI scores at 3 months and the incidence of procedure-related complications. The study protocol was approved by the local ethics committee, and the study was conducted in accordance with the principles of the Declaration of Helsinki.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Etlik
    • Ankara, Etlik, Turkey (Türkiye), 06010
      • University Of Health Sciences, Gulhane School Of Medicine, Department Of Algology,

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Adults aged 18 to 75 years Diagnosis of chronic coccydynia lasting longer than 3 months Numeric Rating Scale (NRS) score ≥ 4 at baseline Inadequate response to conservative medical treatment Ability to understand the study procedures and provide written informed consent

Exclusion Criteria:

Acute coccygeal fracture or recent trauma Local or systemic infection Known malignancy involving the pelvic or sacrococcygeal region Coagulation disorders or ongoing anticoagulant therapy that cannot be safely discontinued Known allergy to local anesthetics or materials used in the procedure Severe psychiatric disorders or cognitive impairment interfering with study participation Pregnancy or breastfeeding

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: Ganglion Impar Radiofrequency Ablation; Participants underwent fluoroscopy-guided ganglion impar thermal radiofrequency ablation.	Procedure: Ganglion impar radiofrequency ablation; Thermal radiofrequency ablation of the ganglion impar performed under fluoroscopic guidance using standard interventional pain management techniques.
Experimental: Coccygeal Nerve Radiofrequency Ablation; Thermal radiofrequency ablation of the coccygeal nerve performed under ultrasound guidance using standard interventional pain management techniques.	Procedure: Coccygeal nerve radiofrequency ablation; Thermal radiofrequency ablation of the coccygeal nerve performed under ultrasound guidance using standard interventional pain management techniques.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Pain reduction at 3 months	Pain intensity was assessed using the Numeric Rating Scale (NRS). The primary outcome was defined as the proportion of patients achieving at least a 50% reduction in NRS score at 3 months compared with baseline.	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional improvement at 3 months	Functional disability was evaluated using the modified Oswestry Disability Index (MODI). A reduction of at least 50% in MODI score at 3 months compared with baseline was assessed.	3 months
Change in pain intensity over time	Changes in pain intensity were assessed using the Numeric Rating Scale (NRS) at baseline, 3 weeks, and 3 months after the procedure.	Baseline, 3 weeks, and 3 months
Procedure-related complications	The incidence of procedure-related adverse events and complications was recorded throughout the follow-up period.	Up to 3 months

Collaborators and Investigators

• Sponsor: Saglik Bilimleri Universitesi
• Investigators: Study Director: ALP E Çelenlioğlu, MD, Saglik Bilimleri Universitesi

Publications and helpful links

General Publications

• Genc Perdecioglu GR, Yildiz G. Coccygeal Nerve Blockade vs. Impar Ganglion Blockade in Coccydynia: A Randomised Clinical Trial. Cureus. 2024;16(9):e69118.
• Can E, Yildiz G, Akkaya OT, et al. Ultrasound-Guided Coccygeal Nerve Radiofrequency Ablation and Steroid Injection: Combination Therapy for Coccydynia. J Ultrasound Med. 2024;43(1):57-64.
• Choudhary R, et al. Improvement in pain following ganglion impar blocks and radiofrequency ablation in coccygodynia patients: a systematic review. Rev Bras Ortop (Sao Paulo). 2021;56(5):558-566.
• Elkhashab Y, Ng A. A review of current treatment options for coccygodynia. Curr Pain Headache Rep. 2018;22(4):28.
• Patijn J, Janssen M, Hayek S, Mekhail N, Van Zundert J. Coccygodynia. Pain Pract. 2010;10(6):554-559.

Study record dates

Study Major Dates

• Study Start (Actual): November 11, 2024
• Primary Completion (Actual): September 30, 2025
• Study Completion (Actual): September 30, 2025

Study Registration Dates

• First Submitted: February 16, 2026
• First Submitted That Met QC Criteria: February 16, 2026
• First Posted (Actual): February 23, 2026

Study Record Updates

• Last Update Posted (Actual): February 23, 2026
• Last Update Submitted That Met QC Criteria: February 16, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Keywords: Chronic coccydynia Ganglion impar Coccygeal nerve
• Other Study ID Numbers: GULHANE-ALG-COCCY-RF-2025-01

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: De-identified individual participant data underlying the results reported in the published article.
• IPD Sharing Time Frame: 3 months after publication
• IPD Sharing Access Criteria: Access to de-identified individual participant data and supporting documents, including the study protocol and statistical analysis plan, will be granted to qualified researchers upon reasonable request. Requests will be reviewed by the study investigators and must include a methodologically sound proposal. Data sharing will be conducted in accordance with institutional policies and applicable data protection regulations.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

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