Paracoccygeal Corkscrew Approach to Ganglion Impar Injections for Tailbone Pain

Rare complication of ganglion impar blockade with the transsacrococcygeal approach: A case of rectal perforation

Although it has been reported that caution should be exercised in terms of rectal perforation, as the ganglion impar is located just behind the rectum in the presacral space, the authors could not find any case or images of rectal perforation occurring during ganglion impar blockade in the literature. In this report, the case of a 38-year-old female with rectal perforation that developed during ganglion impar blockade, performed by the transsacrococcygeal approach under fluoroscopy guidance, is presented. Wrong needle selection and the structurally short presacral space of the patient may have influenced the development of rectal perforation in the patient. This study presents the first case and images of rectal perforation in the literature that developed during the application of ganglion impar blockade using the transsacrococcygeal technique. In ganglion impar block applications, technically appropriate needles should be used, and care should be taken in terms of rectal perforation.

Ganglion Impar Block: A Magic Bullet to Fix Idiopathic Coccygodynia

Coccygodynia (coccydynia) is a painful condition of the perineum in the region of the tailbone or coccyx, aggravated by sitting on hard surfaces. It is frequently associated with injuries to the coccyx following direct trauma. Nevertheless, idiopathic coccygodynia without antecedent trauma history is not uncommon. Most of these patients respond to anti-inflammatory medications and physical therapy. Those who are unresponsive may require additional intervention for pain relief. Blockade of ganglion impar, the terminal end of the pelvic sympathetic chain, can dramatically alleviate the pain in patients suffering from coccygodynia. In the current case series, four patients in the age range of 21 to 69 years suffering from chronic idiopathic coccygodynia (female: male ratio of 1:1) were treated with ganglion impar block. All four patients received a course of medical management, and two of the patients additionally received local infiltration of the coccyx before ganglion impar block administration. The block was performed with fluoroscopy guidance by either the trans-sacrococcygeal joint approach or the intra-coccygeal joint approach. The pre-intervention average numeric rating pain score (NRS) was 7.5. After a single ganglion impar block intervention, all four patients experienced complete pain relief (NRS=0). No patients required a repeat injection, and all were pain-free for the entire one-year follow-up period.

Improvement in Pain Following Ganglion Impar Blocks and Radiofrequency Ablation in Coccygodynia Patients: A Systematic Review

Nearly 90% of cases of coccydynia can be managed with conservative medical treatment; the remaining 10% need other invasive modalities for pain relief, such as ganglion impar block (GIB) or radiofrequency ablation (RFA) of the ganglion impar. A systematic research was conducted of PubMed, MEDLINE, and Google Scholar to identify studies reporting pain relief in terms of visual analogue scale (VAS), or its counterparts, following GIB or RFA in coccydynia patients with the purpose to determine the efficacy of GIB and RFA of the ganglion impar in controlling pain in coccydynia patients. Seven studies were delineated, with a total of 189 patients (104 in GIB group and 85 in RFA group). In the GIB group, the mean VAS improved from 7.83 at baseline to 3.11 in the short-term follow-up, 3.55 in the intermediate-term follow-up, and 4.71 in the long-term follow-up. In the RFA group, the mean VAS improved from 6.92 at baseline to 4.25 in the short-term follow-up, and 4.04 in the long-term follow-up. In the GIB group, a 13.92% failure rate (11/79) and a 2.88% complication rate (3/104) were reported, while in the RFA group, a 14.08% failure rate (10/71) and no complications (0%) were reported. Total success rate was > 85% with either modality. Ganglion impar block and RFA of the ganglion impar are reliable and probably excellent methods of pain control in coccydynia patients not responding to conservative medical treatment. However, a demarcation between responders, non-responders, and late non-responders should be considered, and larger studies with a longer follow-up (> 1 year) are needed.

Interventional Therapies for Pain in Cancer Patients: a Narrative Review

PURPOSE OF REVIEW

Pain is a prevalent symptom in the lives of patients with cancer. In light of the ongoing opioid epidemic and increasing awareness of the potential for opioid abuse and addiction, clinicians are progressively turning to interventional therapies. This article reviews the interventional techniques available to mitigate the debilitating effects that untreated or poorly treated pain have in this population.

RECENT FINDINGS

A range of interventional therapies and technical approaches are available for the treatment of cancer-related pain. Many of the techniques described may offer effective analgesia with less systemic toxicity and dependency than first- and second-line oral and parenteral agents. Neuromodulatory techniques including dorsal root ganglion stimulation and peripheral nerve stimulation are increasingly finding roles in the management of oncologic pain. The goal of this pragmatic narrative review is to discuss interventional approaches to cancer-related pain and the potential of such therapies to improve the quality of life of cancer patients.

Corticosteroid injection for coccydynia: a review of 241 patients

Aims

We aimed to establish the short- and long-term efficacy of corticosteroid injection for coccydynia, and to determine if betamethasone or triamcinolone has the best effect.

Methods

During 2009 to 2016, we treated 277 patients with chronic coccydynia with either one 6 mg betamethasone or one 20 mg triamcinolone cortisone injection. A susequent injection was given to 62 (26%) of the patients. All were reviewed three to four months after injection, and 241 replied to a questionnaire a mean of 36 months (12 to 88) after the last injection. No pain at the early review was considered early success. When the patient had not been subsequently operated on, and indicated on the questionnaire that they were either well or much better, it was considered a long-term success.

Results

At the three- to four-month review, 22 (9%) reported that they had no pain. The long-term success of one injection was 15% and rose to 29% after a second injection. Logistic regression tests showed that both early success (odds ratio (OR) 5.5, 95% confidence interval (CI) 2.1 to 14.4; p = 0.001) and late success (OR 3.7, 95% CI 1.7 to 8.3; p = 0.001) was greater with triamcinolone than with betamethasone. Late success was greater for patients with symptoms for less than 12 months (OR 3.0, 95% CI 1.4 to 6.7; p = 0.006). We saw no complications of the injections.

Conclusion

We conclude that the effect of corticosteroid injection for coccygodynia is moderate, possibly because we used modest doses of the drugs. Even so, they seem worthwhile as they are easily and quickly performed, and complications are rare. If the choice is between injections of betamethasone or triamcinolone, the latter should be selected.

Cite this article: Bone Joint Open 2020;1-11:709–714.

Risk of rectal puncture due to needle entry into the presacral space: Importance of measuring the distance between the rectum and sacrococcyx, and the thickness of the sacrococcyx

During ganglion impar block, the needle may approach the presacral space and the sacrum may be penetrated during caudal anesthesia. Because the rectum is in front of the sacrococcyx and is thus at risk for puncture, it is important to determine the distance between the sacrococcyx and rectum, as well as the thickness of the sacrococcyx.Computed tomography was used to measure the distance between the rectum and sacrococcyx, as well as the thickness of the sacrococcyx. The distances between the coccyx and rectum, sacrococcygeal joint and rectum, sacral level 5 ('sacrum 5') and rectum, and 'sacrum 4 to 5 junction' and rectum were measured. The results were compared based on the presence or absence of stools in the rectum. The thickness of the sacrococcyx was measured at the sacrum 4 to 5 junction and sacrococcygeal joint.In total, 1264 patients were included in this study. All distances were less than 1 mm in both males and females, with the exception of the distance between the coccyx and rectum in males. In both males and females, there was no significant difference in distance between the sacrococcyx and rectum according to the presence or absence of feces in the rectum, but there was a difference in the distance between sacrum 5 and the rectum in males (P = .048). Several male and female patients showed thicknesses of less than 5 mm at the sacrococcygeal joint.Some patients have a distance of less than 1 mm between the sacrum and rectum. Practitioners should exercise caution when applying a needle to the presacral space. If the sacrum is accidentally penetrated during caudal block, rectum puncture cannot be ruled out. Excretion of feces does not influence the distance between the sacrococcyx and rectum in females.

MR-guided perineural injection of the ganglion impar: technical considerations and feasibility

OBJECTIVE

Perineural ganglion impar injections are used in the management of pelvic pain syndromes; however, there is no consensus regarding the optimal image guidance. Magnetic resonance imaging (MRI) provides high soft tissue contrast and the potential to directly visualize and target the ganglion. The purpose of this study was to assess the feasibility of MR-guided percutaneous perineural ganglion impar injections.

MATERIALS AND METHODS

Six MR-guided ganglion impar injections were performed in six human cadavers. Procedures were performed with a clinical 1.5-Tesla MRI system through a far lateral transgluteus approach. Ganglion impar visibility, distance from the sacrococcygeal joint, number of intermittent MRI control steps required to place the needle, target error between the intended and final needle tip location, inadvertent punctures of non-targeted vulnerable structures, injectant distribution, and procedure time were determined.

RESULTS

The ganglion impar was seen on MRI in 4/6 (66 %) of cases and located 0.8 mm cephalad to 16.3 mm caudad (average 1.2 mm caudad) to the midpoint of the sacrococcygeal joint. Needle placement required an average of three MRI control steps (range, 2-6). The average target error was 2.2 ± 2.1 mm. In 6/6 cases (100 %), there was appropriate periganglionic distribution and filling of the presacrococcygeal space. No punctures of non-targeted structures occurred. The median procedure time was 20 min (range, 12-29 min).

CONCLUSION

Interventional MRI can visualize and directly target the ganglion impar for accurate needle placement and successful periganglionic injection with the additional benefit of no ionizing radiation exposure to patient and staff. Our results support clinical evaluation.

One is the loneliest number: a review of the ganglion impar and its relation to pelvic pain syndromes

The ganglion impar is often overlooked as a component of the sympathetic nervous system. Despite its obscurity, this ganglion provides a pathway for neurons by accommodating postganglionic sympathetics, visceral afferents, and somatic fibers traveling to and from the pelvis. Its classic anatomic location as described in the 1720's held up until recently, with the current literature now revealing a great deal of anatomical variability. This variation becomes important when the ganglion impar is used as a treatment target for patients with chronic pelvic pain - its primary clinical implication. The aim of this review was to provide a better understanding of the anatomy of ganglion impar, accounting for variation in size, shape, and location. In addition, the clinical importance and treatment modalities associated with the ganglion impar are outlined.