RecruitingComparing Reports Recorded by the Patients at the Time at Which They Feels Pain to What Patients Report at Monthly Visits to Assess Symptoms of Musculoskeletal Diseases.Patients will be introduced to the use of a mobile application for their smartphone to record the Ecological Momentary Assessment (EMA). This app will ask the patients to assess their pain and function two times daily for 2 months. After 1 month and at the end of the 2 months, follow-up visits will be performed and patients will be asked to retrospectively evaluate the pain that they suffered and the level of function they had during the last month.