SINGLE STAGE KNEE ARTHROPLASTY REVISION SURGERY, OUR EXPERIENCE WITH ELEVEN CASES AND REVIEW OF THE LITERATURE
Authors:   1Department of Orthopaedic Surgery, Olympion Medical Center, Patras, Greece 2Department of Rehabilitation Sciences, University of Patras, Greece 3Department Anatomy – Histology – Embryology, University of Patras 4Orthopaedic Department, University of Ioannina, Greece
Published: February 2021

Knee replacement is a widely performed and very successful procedure for the management of knee arthritis. Nevertheless, it is postulated that a total of 2-5% of primary and revision total knee arthroplasties (TKAs) is infected every year [1,2]. Despite the low incidence, the absolute numbers of prosthetic joint infections (PJIs) are growing, owing to an increased number of replacement surgeries, and are associated with significant morbidity and socioeconomic burden [3,4]. Although several definitions of PJI exist, Musculoskeletal Infection’s Society (MSIS) definition is based on strict criteria and is one of the most used [5]. Patients with certain risk factors have an increased risk to develop PJI [6,7]. Risk factors include presence of systemic or local active infection in an arthritic knee; previous operative procedures in the same knee, diabetes mellitus, malnutrition, smoking, alcohol consumption, co-morbidities, and immunosuppression; end-stage renal disease on hemodialysis, liver disease, intravenous drug abuse, and low safety operative room environment. PJIs are classified according to the depth of infection, to superficial and deep infections. Superficial infections are limited to the incision and superficial tissues, while deep infections, that involve deep layers, may occur up to one year postoperatively, and influence surgical management strategy. Timing of infection is also an important factor in guiding treatment. PJIs are classified to acute postoperative, within a month of the index procedure, acute haematogenous, presenting with acute symptoms in a previously well – functioning joint, and late chronic, where infection develops later than one month postoperatively [8]. Management of PJI’s is mainly surgical, reserving conservative treatment for patients unable to undergo surgery [9]. Surgical options include debridement and retention of the prosthetic implants (DAIR), two – stage exchange revision, single – stage exchange revision, permanent resection arthroplasty, and finally amputation as the last measure [10]. DAIR is a viable option in early stages of acute infections, but established chronic infections necessitate more radical methods. Two – stage revision that was originally described by Install [11], secondly modified through the development of static spacers [12], and then articulating spacers [13], is considered the gold standard of TKA infection management [14]. A large volume of literature reports successful eradication of PJIs in more than 90% of patients using this approach [15,16,17]. Nevertheless, this procedure is costly, time-consuming, develops stiffness, arthrofibrosis, impairs mobility and increases inpatient stay. Single-stage revision arthroplasty for infection was first described in the 1980s [18, 19], has gained popularity for use in selected patients [20]. Infection control using this approach is achieved in 67% to 95% of patients [21, 22, 23, 24]. Furthermore, it is associated with less patient morbidity, improving functional outcome and reducing cost [25, 20]. This paper seeks to systematically review the results of using single – stage revision arthroplasty for chronic infection of TKAs. Furthermore, we report our experience with eleven cases of chronic knee arthroplasty infection, which were treated with the aforementioned technique.