A female Bernese mountain dog of 5.5 years old was referred to the Ghent University Clinic becauseof septic arthritis of the left stifle joint after an explorative arthrotomy. The pathogenic germwas a multiresistant Staphylococcus aureus (MRSA). The stifle joint was operated on again, flushedand the dog was treated with meropenem (Meronem®, NV AstraZeneca SA, Brussels, Belgium) subcutaneouslyfor a period of eight weeks. During that period, the cranial cruciate ligament ruptured inthe affected stifle joint. Therefore, a treatment with a tibial tuberosity advancement technique, i.e. TTARapid was conducted. Despite the infection, the severe symptoms and the concomitant rupture of thecruciate ligament, the dog made a full recovery.Multiresistant bacteria are difficult to treat and demand a thorough approach of the attending veterinarian,a strong commitment of the owner and the exceptional use of potent, “last resort” antibioticsguided by antibiogram results. In this case report, it is demonstrated that even severe cases of postoperativeinfection with MRSA can be managed successfully with proper treatment.