Hello, I have studied your case. Pain and swelling in knuckles can be due to Rheumatoid arthritis. It can also be there in psoriatic and other inflammatory arthritis. I would recommend you to get following investigations for your daughter. 1.ESR, CRP and Ra factor 2. Anti ccp antibody If there is elevation of any these tests than it will confirm that she is having Rheumatoid arthritis. In that condition she needs to take treatment accordingly. I hope these steps will be helpful for you. Let me know if there is any other followup questions. thanks.