The paper presents the cases of tree children with clavicular swelling and a different final diagnosis that offered the opportunity to discuss the key points for the differential diagnosis of clavicular swelling and to draw a rational diagnostic work-up underlining the decisive role of MRI. Although several causes (in order: Chronic Recurrent Multifocal Osteomyelitis, Ewing sarcoma, Tietze syndrome) of clavicular swelling are proposed, it is essential to highlight that main causes are represented by neoplastic and inflammatory causes. However, even if clinical and anamnestic assessment are suitable to disentangle from diagnostic incertitude, imaging is often useful to obtain a diagnosis, before (or even without) biopsy. It is anyway mandatory to rule out neoplasia in all non-traumatic clavicular swelling
