Request her records and read through to see if there are any "incidental findings". There may be something else causing the issue. I can't sit on my right butt cheek at all and I have multiple Tarlov cysts in my sacral area pinching those nerves. Sounds awfully familiar. Please keep us posted if you find something that helps the pain.

@bkruppa Be sure to check with your doctor. What does the MRI or xrays of back show? The doctor may like or not like the inversion table aspect (opinions vary). Be aware, it is clearly counterindicated with high blood pressure. Your blood pressure in your brain goes up somewhat - so you don't necessarily want to overdo inversion, either. Also, it is more important to do it frequently than for a long time (i.e. I still work but do it am and evenings; you could do 2-4 times a day for a few minutes each if you're home a lot). I got some of that info off the Teeter website. One pain Dr. told me don't try doing it when muscles are "cold" as you can trigger spasms (those of us with DDD know all about those spasms) - so I do a couple minutes of inversion at the end of my stretches / TRX suspension exercises - not first thing when I get up in the morning and you're stiff).

You need to go slowly unless your vertebrae can handle it (I could go fully inverted from the start - but my bulges aren't too bad and I also hung from my hands at the gym to elongate my spine every other day before buying the table (but hanging upside down is more mass on the lower back and vertebra crack and make popping sounds from higher up when I invert -it does work). I bought the Ironman inversion table on Amazon (comfortable ankle clamps - but I wear boots when clamped into the machine), Teeters are well known but a little pricier. As I mentioned, and everyone is guessing when it comes to pain in these regions of the body, but one of the therapists I've been working with told me two things I think are true statements. One thing he said: "If pain changes with time, it's most likely not (at least fully) structural." That being said, the soft tissues clamping on nerves are probably a common source of pain - not a ligament (bones and ligaments = structural; the pain wouldn't be as likely to vary much from hour to hour and day by day). It sounds like your wife's pain changes with time (as done mine. I'm 100% sure my pain is muscles clamping on nerves, but a nerve pinch does exist up above complements of my lumbar discs, I suppose). Second, he told me minor bulges can be remedied or bettered using an inversion table. All the things I've done, including the inversion table and other stretches / exercises (I mentioned psoas / quadratus lumborum / extermely deep inspirations / separately in other posts) all can help. In the reviews for inversion tables, many people with DDD and sciatica raved about how some of the pains got better / went away. Many do swear by these tables if the nerves are getting pinched. You get a lot of ideas and knowledge from reading the comments about the inversion tables from user reviews. The Ironman on Amazon was about $200.00, I think, and it is heavy to move - not real portable. I've tried a Teeter at my brother in law's house. I like my ironman better. I still use it everyday.

Hi there, I do not have this problem, but I’m a PT and we have actually more people than you would think with this or very similar problem.
I did not read through prior feeds so this may have already been suggested, but see if you can find a pelvic floor specialist (PT) or one that knows how to do nerve glides for this region as it may not be just the pudendal nerve as there are many nerves off the lumbosacral plexus and if the fascia is tight surrounding it (yes-psoas definitely could be clamping down causing symptoms) then those muscles and tissues need to be released.
If she has been sitting funny bc of it she likely has some thoracic and lumbar alignment issues now and may have a ‘functional’ scoliosis developing (functional meaning she wasn’t born with it, but bc of postural dysfunction her muscles have pulled her spine into various curvatures that is correctable with both manual therapy and specific neuromuscular re-education). These postural faults could also be causing or feeding into the problem even if it gives temporary relief sitting like that.
The pelvis and sacroiliac joint need to be assessed and corrected if out of alignment.
So basics that any good manual PT (one that specializes in manual therapy) can do is correct lumbar facet dysfunction followed by pelvic dysfunction, followed by releasing the tissue throughout that whole region as the fascial system overlaps and even her abdominal fascia up to her ribs I bet is tight as well as in her low back, pelvis and down to both knees.
Lastly, I’d work on checking nerves you can glide (sciatic, femoral and obturator) and do some nerve glides, teach how to perform at home and if a pelvic floor PT-prob knows some fancy ones that are more specific to that area.
After all that correction manually, then comes core stabilization of the transverse abdominis, pelvic floor and multifidi-basics first (Sahrmann) and then work on correcting posture (schroth-seated and sidelying).
Sorry for all that, but just wanted to help. Feel free to copy and paste and print all that out if you go to PT they’ll know what to do (if you find a good one). If they just use modalities (Ultrasound, estim, ice/heat, ionto) and exercise alone, you aren’t going to likely fix the problem. IMO. She should feel immediate relief in the first 3-4 visits-if not, may need to shop around. Look for (OCS, COMT, FAAOMPT, etc) for initials after their PT, DPT. Good luck