This is an observational study that does not change routine care.

The primary objective of this study is to investigate the correlation between the administration of an antibiotherapy able to prevent biofilm formation according to the results of the Antibiofilmogramme test, and the relapse of the infection for patient with orthopaedic device-related infection.

The secondary objectives are:

A. Investigate the role of antibiogram-antibiofilmogramme concordance (in terms of S. aureus strains and prescribed antibiotics) in orthopaedic device-related infection management.

B. Investigate the capacity of S. aureus isolates to form biofilm in presence/absence of antibiotics.

C. Create an S. aureus strain collection for future ancillary studies

Inclusion Criteria:

• The patient must have been informed and received a non-opposition consent form
• Patient with a monomicrobial S. aureus bone and joint infections
• Patient with prosthetic or orthopaedic device

Exclusion Criteria:

• Bone and joint infection from pressure ulcer, vascular injury or diabetic foot ulcer
• Polymicrobial prosthetic joint infection
• The patient is participating in, or has participated in within the past 3 months, another interventional study, or is currently in an exclusion period determined by a preceding study
• Patient is under judicial protection, under tutorship or curatorship
• The patient expresses his opposition to participate to the study
• It is impossible to correctly inform the patient
• The patient is pregnant, parturient or breastfeeding
• Emergency situation precluding correct study implementation

The study population is composed of patient with a monomicrobial S. aureus orthopaedic device-related infections.