http://www.aboutarachnoiditis.org/content/articles/unmentionables/unmentionable_items-4pelvic.html
Chronic or recurring pain or aching in the rectum, with episodes lasting 20 minutes or longer, with no apparent organic (physical) disease to account for the pain. Levator ani syndrome seems to involve muscle spasm in the pelvic floor muscles.
This syndrome may therefore be diagnosed rather than the more likely cause of persistent rectal pain in arachnoiditis, which is pudendal neuralgia.
Treatment of levator ani syndrome includes (a) hot baths, (b) non-steroidal anti-inflammatory drugs(NSAIDs), (c) muscle relaxants, (d) levator muscle massage, (e) electrical stimulation, and (f) EMG-based biofeedback.