@Xianders Hey it's very nice of you to think of her. But I also think it's best if you bring your mom to the hospital for a proper check-up to identify the proper cause, severity of the pain, and get the recommended course of action from the doctors before buying a massage chair. They are pretty good and can help with back pain for sure, but if your mom's situation is really bad, and hypothetically, if it's something serious like muscle damage then it won't help much.
This is just my personal experience but I had sciatica from bad postures and long sitting hours at work, being the dumbass that I was and still am, I tried to massage at home and used a massage machine but it didn't help. Got to the hospital when I couldn't straighten my leg and the doctor yelled at me non-stop for about 15minutes because my muscles were starting to lock up and could have potentially lead to permanent damage if I stretched the wrong way. Got it sorted out with a chiropractor after everyday sessions for 3 weeks + doing the recommended physical at home.