Ganglion Impar Block
The ganglion impar (also called the ganglion of Walther) is the terminal ganglion of the sympathetic chain, located just anterior to the sacrococcygeal junction — the junction of the sacrum and tailbone. A ganglion impar block targets this nerve structure to relieve pain in the perineal, coccygeal, and rectal regions.
Conditions Treated
- Coccydynia (tailbone pain): Persistent tailbone pain after fall, childbirth, or without identifiable trauma. Ganglion impar blocks are one of the most effective interventions for this often frustrating condition.
- Rectal and anal pain: Including proctalgia fugax and anorectal pain syndromes
- Pelvic floor pain
- Perineal pain after prostate cancer treatment (surgery, radiation, or brachytherapy)
- Vulvodynia with perineal component
- Cancer pain involving the rectum, anus, or perineum
The Procedure
Under fluoroscopic guidance, the needle is advanced through or alongside the sacrococcygeal ligament to reach the anterior surface of the sacrococcygeal junction — where the ganglion impar is located. After contrast confirms correct positioning, local anesthetic (with or without steroid) is injected.
For cancer pain or severe refractory coccydynia, a neurolytic (permanent) block using small amounts of absolute alcohol may be recommended.
Results
For coccydynia, ganglion impar blocks have shown success rates of 60–90% in published series — making them significantly more effective than local steroid injections into the coccyx. Relief typically lasts weeks to months, and the procedure can be repeated.
Contact Us
Tailbone pain and pelvic floor pain are conditions that respond well to targeted intervention. Call 516-492-3100 to discuss whether a ganglion impar block may help you.