I would love to see you go to a physical therapist trained in McKenzie technique!
From what you describe, it sounds like it would work for you. Or at least give it a try!
I've worked with lots of post-fusion folks with adjacent instability. There is hope! Generally the McKenzie therapist will give you ONE exercise for your back and ONE exercise for your neck, which you do every hour. (takes about 30 seconds) The exercise is the one that works with the mechanical behaviour of your disc and helps put it back into place. (one person's exercise isn't the same as another person's, just like their discs aren't exactly the same. you'll do a couple different things, an the therapist will help you choose the one that works best)
You keep the exercises up until you've been pain-free (meaning the discs have stayed in place) for 5 to 7 days. At that point, they've likely healed into place and you begin a different exercise to strengthen the juicy new scar tissues. After a few days of that, you go back to the McKenzie therapist for your last exercise which is for preventative maintainence.
Then you're on your own with a maintainence exercise you do once a day.
I've been working in a McKenzie clinic for only a few months, and have seen better success in shorter time than I ever saw in all my years in standard PT clinics.
The website lists McKenzie clinics and PT's who are McKenzie trained. I'm sure there's a PT near you. A "Diplomate" (I think they are designated with "Dip" on the website) would be best, but a "Certified" therapist (designated "Cert" I think) would be very good also.
http://www.mckenziemdt.org/
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