Eligible patients who are interested in the trial will be asked to provide written informed consent to participate. The examiners will allocate the participants in an unique study group. Participants will then complete several questionnaires at baseline, 3, 6, 12, 18 and 24 months after the beginning of the study. A blinded examiner will deliver these questionnaires. Subsequent sessions will occur at the follow-up visits. Participants will be asked about any problems they had had during the previous months before following-up. There will be brief discussion about whether participants have subjected for any treatment (physical, pharmacological, injection and/or no treatment).