Disclosures: Jinpu Li, MD: Nothing to disclose

Case Description: 60-year-old female presented with left vaginal wall pain for 1 year. Cramp/pressure in nature, 5-8/10 VAS, radiates to the vulva and bladder, with dyspareunia and pain after defecation. No dysuria, urinary frequency or urgency. She had TAH/BSO at age 42 for endometriosis and chronic pelvic pain. She was relatively pain free after that until about a year ago. Current pain was different from her previous endometriosis pain.

Setting: Tertiary referring center

Patient: 60-year-old female

Assessment/Results  She tried baclofen, hyoscyamine, pelvic floor PT, and pudendal nerve and ganglion impar block, which did not help. We tried methylprednisolone and ropivacaine injection to the left obturator internus, which gave her about 2 months of relief. She then received 50 unit of onabotulinum toxin A injection, which gave her 3 months of good relief.

Discussion: Chronic pelvic pain (CPP) is a nonspecific term to describe neuropathic symptoms, such as paresthesias, numbness, burning or lancinating pain in the pelvis, perinea, anus, and genitals. It is often aggravated by sitting on hard surfaces, urination, defecation, intercourse and ejaculation. The etiologies can be urologic, gastrointestinal, urogenital, psychological, neurological and musculoskeletal. Studies showed that 14-22% of CPP has myofascial dysfunction of the pelvic floor. The fascia of the obturator internus contributes to the formation of the pudendal canal and when thickened might compress the passing pudendal nerve. Intravaginal blind technique was traditionally used to inject obturator internus. Fluoroscopy guided injection was developed in the past decade. Steroid with local anesthetics, and less commonly botulinum toxin, are used. The precise mechanism of action of botulinum and the relative action on the muscle and pudendal nerve remain unclear. A randomized control study is needed to confirm it is efficacy in the future.

Conclusion: Obturator internus botulinum toxin injection could be a therapeutic option for chronic pelvic pain that is refractory to other therapies.

Level of Evidence: Level V

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PM&R Meeting Abstracts - https://pmrjabstracts.org/abstract/fluoroscopy-guided-obturator-internus-onabotulinum-toxin-a-injection-to-treat-refractory-chronic-pelvic-pain-a-case-report/