An observational study in Dorsal Root Ganglion, Pulsed Radiofrequency and Chronic Pain, sponsored by Ankara University. Not yet recruiting. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2025-01-03.
Sponsored by Ankara University · Observational
Lomber dorsal root ganglion pRF is an interventional treatment options in the treatment of lumbar radicular pain. The goal of this study is to investigate the effect of sensory threshold outcomes on pain severity during dorsal root ganglion pulsed radiofrequency (DRG-pRF). It will also learn effects about disability due to chronic LRP. The main questions it aims to answer are:
Does lower sensory threshold result in lower pain scores and chronic LRP related disability?
Participants will:
Take DRG-pRF procedure for 4 minutes. Visit the clinic at 1. and 3. month for questionnaries.
Lumbar radicular pain is characterized by sharp, stabbing, or throbbing pain radiating to one or more dermatomes. It is a common and challenging condition for clinicians to manage in pain practice. Conservative treatments such as physical therapy, non-steroidal anti-inflammatory drugs, rest, and exercise may fail, leading to chronic pain. In such cases, minimally invasive methods such as epidural steroid injection (ESI) or pulsed radiofrequency (pRF) of the dorsal root ganglion (DRG) may be preferred.
Unlike conventional radiofrequency, pRF does not cause ablation. Due to the intermittent delivery of energy generated by the electric current, the target tissue temperature does not exceed 42°C. This creates a magnetic field that modulates pain without causing neuronal damage.
The DRG, highly sensitive to mechanical compression, is a critical target in radicular pain. There is evidence supporting the efficacy of DRG pRF in chronic lumbar radicular pain. Studies comparing pRF alone or in combination with ESI versus ESI alone have found it effective in providing long-term pain relief. However, despite the increasing body of evidence, studies are lacking on the impact of the proximity of pRF to the target neuronal tissue on clinical outcomes.
The primary aim of this study is to investigate the relationship between the sensory stimulation threshold, indicating the proximity to the target tissue during DRG pRF, and the reduction in Numeric Rating Scale (NRS) scores at the 3-month follow-up. Secondary objectives include examining the relationship between Oswestry Disability Index (ODI) and NRS scores at various assessment time points.
The DRG, highly sensitive to mechanical compression, is a critical target in radicular pain (5,6). There is evidence supporting the efficacy of DRG pRF in chronic lumbar radicular pain. Studies comparing pRF alone or in combination with ESI versus ESI alone have found it effective in providing long-term pain relief (7). However, despite the increasing body of evidence, studies are lacking on the impact of the proximity of pRF to the target neuronal tissue on clinical outcomes.
The primary aim of this study is to investigate the relationship between the sensory stimulation threshold, indicating the proximity to the target tissue during DRG pRF, and the reduction in Numeric Rating Scale (NRS) scores at the 3-month follow-up. Secondary objectives include examining the relationship between Oswestry Disability Index (ODI) and NRS scores at various assessment time points.
2,998 studies on the registry are indexed under Chronic Pain; 706 are open to participants now.
This study's planned enrollment of 150 is above the median of 128 across 706 observational studies indexed under Chronic Pain.
Browse Chronic Pain studies →Ankara University is the lead sponsor of 318 studies on the registry; 65 are open to participants now.
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Candidates who visited algology clinic of Ankara University Medicine Faculty Hospitals to DRG-pRF prodecure for chronic LRP.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Pain lasting ≥3 months NRS score ≥4 Unilateral pain Diagnosis of spinal stenosis or lumbar disc herniation causing root compression, confirmed by magnetic resonance imaging (MRI) according to appropriate diagnostic criteria and classification Failure of conservative treatment
Exclusion Criteria:
Unwillingness to participate in the study Epidural steroid injection within the past month Uncontrolled psychiatric disorders despite medical treatment Systemic or localized infection signs at the procedure site Severe spinal stenosis Allergy to steroids or contrast agents History of cancer Coagulopathy
Procedure: Dorsal Root Ganglion Pulsed Radiofrequency
Using C-arm fluoroscopy, a 22G, 10 cm RF needle with a 5 mm active tip will be directed from lateral to medial towards the vertebral foramen. Once the needle reaches the lateral edge of the pedicle shadow, the C-arm will be adjusted to a lateral view to confirm that the needle is located at the craniodorsal portion of the intervertebral foramen. Sensory stimulation will be delivered through the RF generator at 50 Hz, and paresthesia will be sought in the corresponding dermatome at values between 0.4-0.8 mA. After achieving paresthesia, motor stimulation at 2 Hz will be applied, and the location near the DRG will be confirmed if motor stimulation is not elicited at values less than 1.5 times the sensory threshold. Pulsed RF will then be applied for 4 minutes at a setting of 45 V, 20 ms pulse width, and 2 Hz frequency. Following the application, needle will be directed slightly anterior and after appropriate contrast flow, dexamethasone will be injected.
Postprocedure pain severity at 3th month
Severity of pain will be assessed with Numeric Rating Scale (NRS-11) at 3 months after interventions. NRS-11 is a 11 point likert type scale. Higher scores represent more severe pain.
Time frame: From procedure to 3 months after prodecure
Postprocedure pain severity at 30. min
Severity of pain will be assessed with Numeric Rating Scale (NRS-11) at 30. min after interventions at bedside. NRS-11 is a 11 point likert type scale. Higher scores represent more severe pain.
Time frame: From procedure to 30 minustes after procedure
Postprocedure first month pain severity
Severity of pain will be assessed with Numeric Rating Scale (NRS-11) at 1 month after interventions. NRS-11 is a 11 point likert type scale. Higher scores represent more severe pain.
Time frame: From procedure to 1 month after procedure
Postprocedure first month OSWESTRY scores
Disability will be assessed with OSWESTRY Diasability Index at 1 month. OSWESTRY measures pain related lumbar disability. It has 0 minimum and 100 maximum value. Lower scores represent better outcomes.
Time frame: From procedure to 1 month after procedure
Postprocedure 3th month OSWESTRY scores
Disability will be assessed with OSWESTRY Diasability Index at 3 month. OSWESTRY measures pain related lumbar disability. It has 0 minimum and 100 maximum value. Lower scores represent better outcomes.
Time frame: From procedure to 3 month after procedure
No study locations are listed for this record.
Plan to share: Yes — All data can be shared except personal data.
Supporting information: Study protocol, Statistical analysis plan, Clinical study report, Analytic code
Time frame: 5 years after January 2026
Access criteria: Upon reasonable request
Start is estimated for Jan 2025; primary completion for Jul 2025, 6 months later.
Of 325 non-industry observational studies under Chronic Pain, half reached primary completion within 24 months of starting (the median), counting those still running; a quarter within 12 and three quarters within 54. This study's planned 6 months is below that.
Counting every sponsor, half of 350 studies reached it within 25 months; a quarter within 12 and three quarters within 51.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Dec 2024. You cannot join it, but the record below documents what was studied.
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