The aim of this study is to evaluate the effects of corticosteroid injection verses nighttime splinting as initial treatments on wrist function, quality of life, and sleep quality in patients with rheumatoid disease-related carpal tunnel syndrome. Participants will be randomly assigned to two groups and will receive the following interventions: one group will wear a neutral position night splint for 6 weeks, and the other group will receive a single local injection of methylprednisolone 40 mg as the initial treatment. Follow-up evaluations will be conducted at 6, 12, and 18 weeks to assess wrist function, sleep quality, and quality of life, and to dynamically adjust the treatment plan.