@wornout Welcome to Connect. I realize that PT didn't help much, but something that may help is a special kind of PT called myofascial release. Since you are 6 months out from fusion surgery, I presume that your spine has begun the fusion process which will continue adding to the bone for a couple years as the doctor said. Surgery also creates scar tissue that tightens up and is aggravated by the muscle spasms. I know MFR has helped me before and after cervical fusion surgery. MFR stretches out and releases tight tissue and can help break up the surgical scar tissue. There is a provider search at http://mfrtherapists.com/ and here is our discussion on MFR where you can find a lot of information:

Myofascial Release Therapy (MFR) for treating compression and pain: https://connect.mayoclinic.org/discussion/myofascial-release-therapy-mfr-for-treating-compression-and-pain/

Have you tried this therapy before?