I sympathise, after huge back, thigh and femur injury in late '70's. Have had a lifetime of issues. Two lumbar vertebrae have been fused, but that has led to disc displacement above and below site of original damage.
Biggest gain I made was finding an excellent surgeon who was willing to work with an excellent sports physiotherapist.
In essence, combined efforts have resulted in a well defined exercise regime that has balanced and massively strengthened core muscles.
Hurts like hell when you start, but result is worth it. Off of medication for first time in eleven years.