Participants after first-stage of knee infection reimplantation will be assign to one of two groups: with stem vs. with sleeve. Investigators will check participants on clinical, laboratory and reinfection signs. The main hypothesis is that better mechanical stability of endoprosthesis with sleeves will support infection treatment.

All participants will be treated because of periprosthetic joint infection of the knee, after primary arthroplasty. All participants will be treated with two-stage protocol. In first stage debridement and spacer implantation will be performed. After 6-week antibiotics, when will be absent clinical or laboratory signs of reinfection, second stage will be performed. All participants upon fulfillment all inclusion and exclusion criteria will sign informed consent. With computer software patients will be randomized to one of two groups: with stem vs. with sleeve. After operation all patients will get target antibiotics for 3 weeks. Pre-operation and after on periodic controls will checked the Knee Society Score, The Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC), Visual Analogue Scale. After 2-year observation evaluation of reinfection rate will be performed in both groups.

Inclusion Criteria:

• second-stage of knee reimplantation
• primary knee replacement in primary knee osteoarthritis
• fulfillment of International Consensus Meeting 2018 infection criteria

Exclusion Criteria:

• intraoperative bone defects Anderson Orthopedic Research Institute score >II
• autoimmune disease
• diabetes
• peripheral vascular disease
• congenital or acquired immunodeficiencies
• lack of pathogens after first-stage
• multi-bacterial infection
• multidirectional instability
• lack of patient consent

Study protocol and Informed consent form will be shared

1 year