Maybe we can still be on this forum and say,"Remember when?"
Here are the nutrients found in cumin seed. Your extract probably has substantially more than is listed here: http://www.whfoods.com/genpage.php?tname=foodspice&dbid=91
Here is a very helpful article on IBD and arthropathies!
http://www.medscape.com/viewarticle/750045
After a couple years of taking many supplements, specifically to remedy my worsening SI joint, I've finally narrowed it down to a few factors: 5,000 iu D3 daily, 1-2 grams Black Cumin Seed, and 8 hours of sleep daily. The Black Cumin seed oil was the missing link for me which I discovered a few months ago.
I'm not sure how to classify the type of reoccuring sacroiliac joint pain I get, but I have found something that works for me if I take it daily, in the morning, on an empty stomach (I have had digestive issues when taken with foods and when taken within 3 hours of LDN). If you do research on Black Cumin Seed oil and IBD, or BCS oil's scientific botanical name which isn't actually related to cumin spice at all, you will find that this stuff works locally on the gut's opiate/endorphin system--kinda sorta related to LDN's rebound effect. However, this means you do not want to mix LDN and BCS oil or you will feel nausea. However, while taking BCS oil, I now can have coffee like its water and I no longer am dependent on quality probiotics for solid BMs--this is a significant indicator for me since I've depended on them for 7+ years.
It is a 500 mg black cumin seed extract, called Thymocid, which I take in a supplement by Life Extension called Black Cumin Seed Oil. I previously tried their product with curcumin mixed in, but the single supplement works just as well. I haven't tried any other brands, but this can be found reasonably priced, around $15 per month if taking 2 a day, online at some mega-warehouse websites.
I did not test positive for HLA-B27 and my SI joint pain occurs independent of any digestive flairs, but is directly related to not enough sleep and D3. I only get joint pain in the sacroiliac joint, nowhere else. My useless doctor suggested I start taking Pentasa (or maybe Asascol) daily for this axial joint pain--in my opinion, Pentasa is an expensive placebo, which may have limited efficacy for those with colitis symptoms and maybe peripheral joint pain, foisted onto crohn's patients with generally mild cases.
If I take 2 capsules of Life Extension Black Cumin Seed Oil daily, I don't get my si joint pain. I've been upping my dose occasionally (to 1.5 or 2 grams) if I go days without reaching my 8 hour per night sleep goal and start feeling joint issues arise--I am a hopeless procrastinator when it comes to getting to sleep at a decent time.
Do a scholar.google.com search for "The Joint-Gut Axis in Inflammatory Bowel Diseases" and maybe do another for Black Cumin Seed and inflammation or ibd to see why this might work. I still haven't parsed through that first article...
Please let me/others know if you try this. It might take a couple weeks for the oil to work, maybe not. I didn't take it daily until I gradually noticed the days I didn't take it, due to aforementioned effects. This is actually very worth trying in my personal experience.
Nigella sativa (Black Cumin) Seed Extract Alleviates Symptoms of Allergic Diarrhea in Mice, Involving Opioid Receptors Swantje C. Duncker, David Philippe, Christine Martin-Paschoud, Mireille Moser, Annick Mercenier, Sophie NuttenResearch Article | published 29 Jun 2012 | PLOS ONE 10.1371/journal.pone.0039841
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0039841