Perforating Cutaneous Nerve Injection Efficacy in Chronic Coccydynia: A Randomized, Double-Blind Study

Sisli Hamidiye Etfal Training and Research Hospital

Status and phase: Enrolling; Phase 3; Phase 2

Conditions: Coccyx Injury; Coccyx Disorder

Treatments: Procedure: US Guided Perineural Injection and Neuroprolotherapy

Study type: Interventional

Funder types: Other

Identifiers

NCT06315244

2558

Details and patient eligibility

About

Interventions targeting the perforating cutaneous nerve are relatively new to the literature, with a safe side-effect profile but lacking high-quality studies. Their effectiveness remains at the level of case presentations. According to the hypothesis expressed in these publications, coccydynia might be an overlooked cause due to the compression of the perforating cutaneous nerve where it pierces the sacrotuberous ligament and becomes superficial. Ultimately, it is hypothesized that injection of dextrose into this ligament and the sensory area of this nerve will resolve these symptoms due to nerve entrapment, similar to other entrapment neuropathies treated with 5% dextrose, like carpal tunnel syndrome.

Enrollment: 40 estimated patients

Sex: All

Ages: 18 to 50 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age between 18 and 50 years.
2. Chronic coccyx pain (≥3 months).
3. Pain Visual Analogue Scale (VAS) score ≥4.
4. Pain not alleviated by first-line treatment (physical therapy/oral analgesic therapy + sitting cushion).

Exclusion criteria

1. Injection to the area in the last 3 months.
2. Concurrent mechanical or inflammatory low back pain.
3. Coccyx pain that started during pregnancy or postpartum.
4. History of myelomeningocele or spina bifida.
5. History of sacrococcygeal luxation or subluxation (confirmed by radiography).
6. History of coccyx fracture.
7. Concurrent neurological deficit.
8. Skin disease affecting the injection area.
9. History of malignancy.
10. Pregnancy or breastfeeding.
11. Severe coagulopathy.
12. Infection at the injection site.
13. Neurological or psychiatric diseases, including ongoing depression (Beck Depression Inventory Score >14).

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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40 participants in 2 patient groups, including a placebo group

%5 Dextrose Injection Group

Experimental group

Description:

Participants in this arm will receive an ultrasound-guided injection of 5% dextrose solution into the sacrotuberous ligament and the sensory innervation area of the perforating cutaneous nerve. The intervention aims to alleviate symptoms of chronic coccydynia by reducing nerve entrapment. Participants will continue their existing physical therapy/medical treatment regimen throughout the study.

Treatment:

Procedure: US Guided Perineural Injection and Neuroprolotherapy

Placebo Injection Group

Placebo Comparator group

Description:

Participants in this arm will receive an ultrasound-guided injection of a placebo solution (saline) into the same anatomical region as the experimental group. This arm serves as a control to evaluate the efficacy of the dextrose injection in treating chronic coccydynia symptoms. Participants will continue their existing physical therapy/medical treatment regimen throughout the study.

Treatment:

Procedure: US Guided Perineural Injection and Neuroprolotherapy