Hey sorry guys for the slow reply. In case you didn't notice from my join date and post count I'm not very good at conversing on forums.
It was quite a bit of a journey to get things right again, with probably many things contributing to the improvement. I'll kind of go through it in order, hopefully isn't too long of a post.
The first thing that helped me a bit was chiropractic. I went from not being able to pick anything up to a big deadlift PR of 470 in a matter of about 6 weeks, though things still felt pretty dangerous. Their muscle tension scans indicated some pretty interesting improvement, making me a believer that it was doing some good things. During this time I trained a ton of core stabilization and really concentrated on stretching hamstrings and erector spinae. Seemed to help a bit, but everything in my back was still ridiculously tight all the time, and would flare up through training. Felt like shit in the morning whether I trained or not. The left side of my lower back was always a bother. I figured QL and erector spinae were tight since I was feeling it there, so stretched this area a lot. During this time I got up to about ~500 deadlift.
When I started strongman, things just got a lot worse again due to the training. I had one fateful yoke walk where I felt a rip deep in my back, I still don't know what happened, but it was theorized that it was a tear to a multifidus muscle. Chiropractic was no longer keeping me deadlifting. In fact, I was unable to do so for about a year at this point so I pretty much had to quit everything. Felt pretty terrible. My old stretching routines were not helping (pretty sure they never actually did), so I started getting smarter about it.
I started getting a lot of soft tissue work done (massage, art, graston, etc). At this point I realized that when muscles are tight and inflamed with trigger points everywhere, stretching is pretty much useless. As horribly expensive as it is, having someone physically break down and stretch tissues by hand is the only way to have a tight ball of muscle finally let go and start moving properly again (provided there isn't an underlying cause which remains). Once you are there, stretching is effective once again. I started learning about the multitude of supporting muscles which also needed to function properly (glutes, internal/external rotators, psoas, etc).
Anyways, all this soft tissue work was helping things calm down and I could deadlift again, but 24/7 I still could feel a burning tightness in the lower left side of my back. Everything was tight there, even multifidi and rotatores. When I had a massage therapist try to get there, they were quite crazy.
I finally went to an excellent physio who specializes in hips and is the guy for the canadian olympic speedskating team. paid the $$ for it, and here's where things started to finally come together. This guy basically tested flexibility and strength of most supporting muscles necessary for proper movement. His diagnosis:
-Tight hamstrings (which were easy to stretch and improve)
-Tight psoas (which I could never improve on through stretching)
-Weak/inactive glute medius (which I neglected to take seriously enough initially)
-Weak internal/external rotators (I bought some bands to get better at this, I'm decent now)
-Tight quads and IT band (easy to improve through stretching/rolling and especially soft tissue work)
He then checked the firing patterns of some muscles using ultrasound imaging. He checked the strength of my pelvic floor contractions, which is basically done through the action of squeezing when you stop yourself in the middle of pissing. He'd get me doing this while watching the ultrasound monitor to learn how to contract properly. Once the muscle was firing well, he did the same thing with my transverse abdominis, which was also not firing very well (especially on the right side). He basically said that when one contracts the pelvic floor muscle that the transverse abdominis should also contract subconsciously. Both of these should be contracted during any movement which requires stability here. After a bunch of activation work on that over a few weeks (practicing at home, then checking progress on the monitor once a week), this was happening for me.
Simultaneously, the guy checked the firing patterns of my erector spinae. The muscles whos function is stabilization (transverse abdominis, rotatores, multifidi, etc) should contract before the large erector spinae muscles to ensure stability. On the monitor it became apparent that my iliocostalis on the left side was firing late (or rather, hardly at all). The physio used a TENS machine on this muscle, where it would contract for a few seconds, then relax for several seconds. He had me trying to assist the contraction while it was happening, and release otherwise. I practiced doing this at home with no TENS machine. The first time I deadlifted after doing this, my back felt like it was the first time I had ever deadlifted, but JUST in the muscle which was not previously activating properly. It was crazy. And wouldn't you know it, 3 weeks later I pulled around 570. A big PR.
The final piece of the puzzle for me was (and is to a minor extent) relating to my glute medius and psoas muscles. My psoas has typically been very tight. Even with massage I could never improve this, and stretching would certainly do nothing. I started doing a ton of glute medius activation finally. When this started to go well, my massage therapist went in to the psoas and it just finally let go. If your glute medius is not activating properly, the psoas becomes tight and locked up to compensate, which in turn causes a pelvic tilt and lower back tightness.
Now I have several things that I really like for prehab to keep myself healthy enough to do strongman events on a regular basis.
-Chiropractic (it's not the most important thing but I think it helps)
-Massage (This is especially great as a diagnostic tool to know which muscles are locked up, and what to be currently concentrating on)
-Lower back band traction. This is where I hang upside down from my rack with two heavy bands around my back at the sacrum level. This is great for stretching everything and decompressing the spine. I find this really helps for my psoas. I do this most days for a few minutes.
-Glute medius activation - I still have to work on this a lot to keep my psoas from locking up.
-IT band rolling on a very regular basis
-Hamstring stretching on an infrequent basis
-I do some quick spinal flossing pre-workout movements from that magnificent mobility DVD before I train every time
-I have a DR.Hos tens machine I use on certain muscles sometimes. TENS machines help a lot with activation I've learned. This particular one sucks ass, but it seems to be better than nothing. I might create my own TENS machine one day since I'm an electrical/biomedical engineer. I should be able to figure it out.
-Being happy - it helps.
Anyways hope this isn't too overwhelming or drawn out. It was quite terrible for me, so I took this situation very seriously. If you are really suffering I'm sure you completely understand where I'm coming from.