I used to hear PPMS and think that meant a patient was going to tank rapidly, end up in the worst possible shape, and have to accept it because there were no drugs for that form of the disease. Hopefully, you don't have the same perception because it's an inaccurate one. PPMS can be a steady progression that is slow.
I was dx RRMS in 1998, but I've never had another exacerbation since that first one even though my condition has steadily declined. The more I learn, I think I may have PPMS (or SPMS).
It's alarming to read that there are no drugs for PPMS. I'm not so sure about that. They just don't do trials on that group because it's harder to measure the effectiveness of the drug if they aren't counting exacerbations as a measure. That is changing though.
As far as the question in your post, I would learn as much as possible about spasticity. If your husband feels like he's aged 20 years in the last 2, I suspect he may have that symptom. Mine got way out of control before I even knew that's what it was. I thought I was experiencing the flulike symptoms they warn about with interfuron drugs, so I never complained about it to my doc. I thought walking around bent over and feeling 100 years old was just the price you had to pay to be on Betaseron.
I recently read an article written by an MS expert that said in many cases what is diagnosed as "progressive MS" is actually mismanaged spasticity.
That's my 2 cents worth.
Another bit of advice is to work hard at not letting the dx do a number on you emotionally. That sounds so obvious, but that's the biggest challenge in the beginning. Make sure you have a neurologist who stays current on MS info and who has a positive, hopeful attitude. He/she is your lifeline in the beginning, and you need to align yourself with the right vibe. Also, I would be selective about who you tell. The public has all sorts of impressions about MS. You will be an expert on the disease sooner than you think. At that point you can disclose it if that's what feels right for you, but until then you are somewhat vulnerable, and you don't need people telling you about their Aunt Mable dying in a nursing home from it. I think people are trying to bond and relate when they do that, but avoid giving them the opportunity. It's very bad for your psyche right now while you are in this vulnerable, information gathering stage. Besides that, it's NOT GOING TO HAPPEN.
Wishing you and your husband all of the very best.