The primary outcome criteria of our study is the change of VAS and FIHOA from baseline to the end of treatment. Furthermore, we chose as secondary outcomes the duration of morning stiffness, the Italian version of Health Assessment Questionnaire (HAQ) and the validated Italian version of the Medical Outcomes Study 36-Item Short Form (SF-36) routinary registered in our medical record before the i.a. therapy, at the end of the treatment and after 1, 3 and 6 months.