A 36 yeаr-оld dаtа entry clerk present tо yоur office complaining of tingling and pain in the right thumb and wrist that is usually worse by the end of the day. Occasionally, 4/7 nights per week, she awakens at night from the pain. Phalen's & Tinel's (median nerve compression tests) are both positive. The hand and wrist appear otherwise normal, with full range-of-motion, good perfusion, and no focal signs of inflammation or trauma. Which of the following treatment modalities would be your first choice in alleviating pain in this patient?