Yes, I had this in BOTH legs. Recurred regularly, debilitating, weeks off work etc.
I went to a physio and an acupuncturist when it was really painful.
This got me back on my feet short term.
Decided to look for a long term solution:
Went to chiropracter who said "hmmm, have you been to a podiatrist? You have poor spinal positioning and it looks like it's coming from your feet."
Podiatrist says "yes, one leg is shorter than the other, you need orthotics" (things in shoes to correct feet imbalance).
Back to chiropracter, "yes, better, hmm, spine still a bit off...posture not great which is making it worse, have you tried Alexander technique?"
Off I go to Alexander technique teacher...after 4 weeks I was bent double with agony...week 6 the pain went...week 26 passes, I finish the course, I am now an inch taller (still with the orthotics).
No sciatica for SIX YEARS!!!!!
I also did pilates to keep my spinal muscles strong.
One of these could work for your DH.
If at first you don't suceed....
GP offered painkillers that rendered me a zombie and incapable of coherent speech. Apart from being offered a show on radio 2 this was not helpful in my career! Which is why I went the alternative route.