Hi gp - if the stiffness is from spasticity then massage and heat can help. if the joints are freezing due to this then a lot of care needs to be taken not to damage ligaments, but ROM done correctly can be very relieving too.
there are medications that can help, but you need massage and ROM too often to pay a chiro to do this really.
Some here may put chiros down, but my 2 sons have had life changing results on chronic back issues.
I was just trying to search and find the thread where I put YouTube links to how I used to massage Chris but I couldn't find it. If you go to my profile and then to my website you will find the links but I'm not allowed to directly link to my site in a thread sorry.
or search alsgardens dot net do au