There's not alot that you can do for CTS conservatively outside making them a cock up splint (wrist in 0 to 10 degrees extension) out of thermoplastic. The splint is to be worn during the day, and at night, too, if they have bad symptoms at night. If symptoms are not relieved by the splint, they will have to get it surgically released. (They should have conclusive nerve conduction tests done to confirm that they have CTS, first, though!)