I also thought of SCS, for pain relief if meds are not working, or in addition to meds..
Has she had any PT sessions to see if that might help?

Members can share more, but I found this-
[There are two main types of pain in multiple sclerosis: nerve pain (neuropathic pain) which is caused by damage to the nerves in the brain and spinal cord. This includes altered sensations such as pins and needles, numbness, crawling or burning feelings.]

[About two thirds of people with MS report pain as symptom of their disease. The most common types of pain experience by people with MS are headache, back pain, extremity pain, and muscle spasms. Because the pain comes from the nerves, common pain medicines like aspirin have little or no effect; however, other medications may be effective.] 2 Early MS Symptoms (Pain), Warning Signs, Treatment & Diagnosis