Overview

Affects about 1 to 2% of primary hip and knee replacements
Diagnosis combines clinical findings, CRP, ESR, synovial fluid analysis and intraoperative tissue samples
2018 ICM and EBJIS criteria give a structured approach
A sinus tract to the prosthesis or two positive cultures of one organism confirms infection
DAIR for acute infection, one or two stage revision for chronic infection

Epidemiology

Affects roughly 1 to 2% of primary hip and knee replacements
Patient risks are obesity, diabetes, smoking, immunosuppression and Staphylococcus aureus colonisation
Coagulase negative staphylococci and Staphylococcus aureus are commonest
Biofilm resists antibiotics, so mature infection needs implant removal

Tsukayama

Type	Description
Early postoperative	Within about four weeks
Acute haematogenous	Sudden onset in a well functioning joint
Chronic	Insidious onset beyond four weeks
Positive intraoperative cultures	Positive cultures at presumed aseptic revision

ICM 2018 major criteria are two positive cultures of one organism or a communicating sinus
Minor scores, serum CRP or D-dimer 2, ESR 1, synovial WCC or leucocyte esterase 3
Alpha defensin 3, synovial neutrophil percentage 2, synovial CRP 1
Preoperative score 6 or more infected, 2 to 5 possible, 0 to 1 not infected
Intraoperative histology 3, purulence 3, single positive culture 2, combined 6 or more infected

DAIR for early or acute haematogenous infection under about three to four weeks with well fixed implants
DAIR needs healthy soft tissue, no sinus and biofilm active antibiotics such as rifampicin
Two stage revision with antibiotic spacer for chronic infection
One stage revision for a known organism, good susceptibility, adequate tissue and a competent host
Suppressive antibiotics when surgery is unsuitable

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.