The investigators tested the working hypothesis if 4 weeks of systemic antibiotic treatment in implant-related orthopaedic infections is non-inferior to 6 weeks after complete removal of the infected implant. Randomization 1:1.

The study is completed. It halted prematurely and will not resume; participants are no longer being examined or receiving intervention.

Former description of the study (now completed)

Osteoarticular infections related to orthopaedic implants are associated with substantial morbidity, prolongation of hospital stay, and additional costs. Due to the increasing number of patients with orthopaedic implants in Switzerland, similar to the rest of Europe and elsewhere, the number of infections is expected to increase. While the surgical treatment of these infections has been well studied, the ideal duration of antibiotic therapy after removal (explantation) of the infected implant remains unknown. For almost 40 years, the recommended total duration of post-explantation antibiotic therapy has been 6 weeks. This recommendation is based on expert's personal experience rather than on prospective randomized studies. Shorter treatment would decrease antibiotic-related adverse events and costs hospital stay for patients awaiting an eventual reinsertion of a new implant. If physicians and surgeon prescribe antibiotics for 6 weeks, this duration should be at least supported by evidence.

Inclusion Criteria:

• Adult patients (≥17 years old)
• Total removal of the implant

Exclusion Criteria:

• Primary native joint septic arthritis;
• Co-trimoxazole prophylaxis because of immunosuppression;
• Left-side endocarditis;
• Persistent implant material in the infected area.
• Infections with tuberculosis; mycobacteria; fungi; brucellosis; borreliosis; nocardiosis; and mycoplasmal osteosynthesis infections