The presence of acute osteomyelitis andseptic arthritis are uncommon in neonate. Recognition and treatment of adjacent septic arthritis is a matter of urgency and importance, as it may result in severe sequalae such as sepsis, joint destruction and growth failure if it is not diagnosed andtreated promptly. In this paper we report a case of a 21-days-old neonate girl presented with left humeralosteomyelitis and secondary septic arthritisof the shoulder joint following hepatitis B vaccination. She received medical treatments including supportive care, antibiotics and a surgical drainage procedure. The 3 months follow-up shows scleroticchanges to the proximal humerus in radiograph examination, without clinical manifestation. A long follow up of 1 – 2 years is required to detect all possible sequalae.

Keywords : Osteomyelitis, Neonate, SepticArthritis