Aims. Periprosthetic joint infection (PJI) is a challenging complication of any arthroplasty procedure. We reviewed our use of static antibiotic-loaded cement spacers (ABLCSs) for staged management of PJI where segmental bone loss, ligamentous instability, or soft-tissue defects necessitate a static construct. We reviewed factors contributing to their failure and techniques to avoid these complications when using ABLCSs in this context. Methods. A retrospective analysis was conducted of 94 patients undergoing first-stage revision of an infected knee prosthesis between September 2007 and January 2020 at a single institution. Radiographs and clinical records were used to assess and classify the incidence and causes of static spacer failure. Of the 94 cases, there were 19 primary total knee arthroplasties (TKAs), ten revision TKAs (varus-valgus constraint), 20 hinged TKAs, one arthrodesis (nail), one failed spacer (performed elsewhere), 21 distal femoral endoprosthetic arthroplasties, and 22 proximal tibial arthroplasties. Results. A total of 35/94 patients (37.2%) had spacer-related complications, of which 26/35 complications (74.3%) were because of mechanical failure of the spacer construct, while 9/35 (25.7%) were due to recurrence of infection. Risk factors for internal failure were a construct where the total intramedullary spacer length was less than twice the length of the central osseous defect (p = 0.009), where proximal or distal intraosseous spacer contact was < 10%, and after tibial tubercle osteotomy (p = 0.005). The incidence of spacer complications significantly increased the time to second stage: mean 157 days (42 to 458) in those without complications versus 227 days (11 to 528) with complications (p = 0.014). Conclusion. The failure rate of static antibiotic-loaded cement spacers is much higher than anticipated. Complications of the spacer significantly increased the time to second-stage revision. The risk of mechanical failure is significantly increased if the spacer is less than double the size of the segmental defect, or if inadequate reinforcement is inserted into the residual bone. These findings serve as a guide for surgeons to avoid mechanical complications with static spacers. Cite this article: Bone Joint J 2024;106-B(10):1067–1073

Background. The purpose of this multi-center, randomized clinical trial was to compare static and articulating spacers in the treatment of PJI complicating total knee arthroplasty TKA. Methods. 68 Patients treated with two-stage exchange arthroplasty were randomized to either a static (32 patients) or an articulating (36 patients) spacer. A power analysis determined that 28 patients per group were necessary to detect a 13º difference in range of motion between groups. Six patients were excluded after randomization, six died, and seven were lost to follow-up prior to two years. Results. Patients in the static group had a hospital length of stay that was one day greater than the articulating group (6.1 vs. 5.1 days; p=0.032); no other differences were noted perioperatively. At a mean 3.5 years (range, 2.0 to 6.4 years), 49 patients were available for evaluation. Mean motion arc in the articulating group was 113.0º compared to 100.2º in the static group (p=0.001). The mean Knee Society Score was significantly higher in the articulating cohort (79.4 vs. 69.8 points; p=0.043). Although not significantly different with the sample size studied, static spacers were associated with a greater need for an extensile exposure at the time of reimplantation (16.7% vs. 3.8%) and a higher rate of reoperation (33.3% vs. 12.0%). Conclusions. Articulating spacers provided significantly greater range of motion and better clinical outcomes scores. Static spacers also appeared to affect early postoperative rehabilitation, as evidenced by a longer hospital stay following removal of the infected implant and were associated with a trend towards a greater need for extensile exposures at the time of reimplantation. Further, while it has been commonly believed that static spacers would improve infection control, there was no difference in the failure rate secondary to reinfection and there was a trend towards higher risk of reoperation in patients who received a static spacer. When the soft tissue envelope allows and if there is adequate bony support, an articulating spacer is associated with improved outcomes. For figures, tables, or references, please contact authors directly

Introduction. Extraction of implants due to periprosthetic infection (PJI) following complex revision total knee arthroplasty (rTKA) with extensive hardware can be a daunting undertaking for surgeon and patient alike. We question whether irrigation and debridement (I&D) has a role in this difficult situation with respect to infection control, reoperation, and function. Methods. rTKAs for PJI from 2005–2016 were reviewed. Extensive hardware was defined as: metaphyseal cone/sleeve fixation, distal femoral replacement, periprosthetic fracture hardware, or stems >75mm. Cases were categorized by treatment (I&D or 2-stage exchange). Results. 87 patients were identified with extensive hardware and PJI − 63 I&Ds and 42 2-stages. Follow-up was 3.7 years. Success defined as no re-operation for infection was similar − 38/63 (60.3%) I&D vs 28/42 (66.7%) 2-stage (p=0.54). 26/42 (61.9%) 2-stages required static spacers for post-extraction bone loss or wound problems. Only 14/42 (33%) 2-stages were successfully replanted without re-infection. 11/42 (26.1%) 2-stages had retained spacers while 7/42 (16.7%) 2-stages were eventually fused. In contrast, 38/63 (60.3%) I&Ds maintained original implants without further surgery. 8/63 (12.7%) required repeat I&D; 9/63 (14.3%) underwent eventual 2-stage. Chronic antibiotic suppression was utilized in 53/63 (84.1%) I&Ds and 17/42 (40.5%) 2-stages (p<0.001). Amputation rates were similar − 9/63 (14.3%) I&D vs 7/42 (16.7%) 2-stage (p=0.79). Ambulatory rates were similar − 46/63 (73.0%) I&D vs 24/42 (57.1%) 2-stage (p=0.09). More patients who underwent I&D had a functional TKA at final follow-up (53/63 (84.1%) I&D vs 20/42 (47.6%) 2-stage; p<0.001). Mortality was high − 22/59 (37.3%) I&D vs 13/37 (35.1%) 2-stage (p=1.00). Conclusion. In the setting of PJI following rTKA with extensive hardware, morbidity and mortality is high. I&D with chronic suppression appears as effective as 2-stage procedures in preventing reoperation for infection and maintaining ambulatory status while avoiding the morbidity of 2-stage exchange

Aims

The outcome of repeat septic revision after a failed one-stage exchange for periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat septic revision after a failed one-stage exchange, and to determine whether the Musculoskeletal Infection Society (MSIS) stage is associated with subsequent infection-related failure.

Aims

Single-stage revision total knee arthroplasty (rTKA) is gaining popularity in treating chronic periprosthetic joint infections (PJIs). We have introduced this approach to our clinical practice and sought to evaluate rates of reinfection and re-revision, along with predictors of failure of both single- and two-stage rTKA for chronic PJI.

Aims

Our objective is to describe our early and mid-term results with the use of a new simple primary knee prosthesis as an articulating spacer in planned two-stage management for infected knee arthroplasty. As a second objective, we compared outcomes between the group with a retained first stage and those with a complete two-stage revision.

Aims

The integrity of the soft tissue envelope is crucial for successful treatment of infected total knee arthroplasty (TKA). The purpose of this study was to evaluate the rate of limb salvage, infection control, and clinical function following microvascular free flap coverage for salvage of the infected TKA.

Aims

Two-stage exchange arthroplasty is the most common definitive treatment for prosthetic joint infection (PJI) in the USA. Complications that occur during treatment are often not considered. The purpose of this study was to analyze complications in patients undergoing two-stage exchange for infected total knee arthroplasty (TKA) and determine when they occur.

Aims

The aim of this study was to assess the effects of transferring patients to a specialized arthroplasty centre between the first and second stages (interstage) of prosthetic joint infection (PJI) of the knee.

Two-stage revision surgery for infected total knee replacement offers the highest rate of success for the elimination of infection. The use of articulating antibiotic-laden cement spacers during the first stage to eradicate infection also allows protection of the soft tissues against excessive scarring and stiffness. We have investigated the effect of cyclical loading of cement spacers on the elution of antibiotics. Femoral and tibial spacers containing vancomycin at a constant concentration and tobramycin of varying concentrations were studied in vitro. The specimens were immersed and loaded cyclically to 250 N, with a flexion excursion of 45°, for 35 000 cycles. The buffered solution was sampled at set intervals and the antibiotic concentration was established so that the elution could be calculated. Unloaded samples were used as a control group for statistical comparison.

The elution of tobramycin increased proportionately with its concentration in cement and was significantly higher at all sampling times from five minutes to 1680 minutes in loaded components compared with the control group (p = 0.021 and p = 0.003, respectively). A similar trend was observed with elution of vancomycin, but this failed to reach statistical significance at five, 1320 and 1560 minutes (p = 0.0508, p = 0.067 and p = 0.347, respectively). However, cyclically loaded and control components showed an increased elution of vancomycin with increasing tobramycin concentration in the specimens, despite all components having the same vancomycin concentration. The concentration of tobramycin influences both tobramycin and vancomycin elution from bone cement. Cyclical loading of the cement spacers enhanced the elution of vancomycin and tobramycin.

This review summarises the opinions and conclusions reached from a symposium on infected total knee replacement (TKR) held at the British Association of Surgery of the Knee (BASK) annual meeting in 2011. The National Joint Registry for England and Wales reported 5082 revision TKRs in 2010, of which 1157 (23%) were caused by infection. The diagnosis of infection beyond the acute post-operative stage relies on the identification of the causative organism by aspiration and analysis of material obtained at arthroscopy. Ideal treatment then involves a two-stage surgical procedure with extensive debridement and washout, followed by antibiotics. An articulating or non-articulating drug-eluting cement spacer is used prior to implantation of the revision prosthesis, guided by the serum level of inflammatory markers. The use of a single-stage revision is gaining popularity and we would advocate its use in certain patients where the causative organism is known, no sinuses are present, the patient is not immunocompromised, and there is no radiological evidence of component loosening or osteitis.

It is our opinion that single-stage revision produces high-quality reproducible results and will soon achieve the same widespread acceptance as it does in infected hip arthroplasty.

Antibiotic impregnated articulating spacers are used in two-stage revision total knee arthroplasty to deliver local antibiotic therapy while preserving function. We have observed infection control in greater than 95% of cases with functional outcomes approaching those seen in revision for aseptic loosening. Higher failure has been observed with methicillin resistant organisms.

We present a series of 48 patients with infected total knee replacements managed by the use of articulating cement spacers and short-term parenteral antibiotic therapy in the postoperative period. All patients had microbiological and/or histological confirmation of infection at the first stage of their revision. They all underwent re-implantation and had a mean follow-up of 48.5 months (26 to 85).

Infection was successfully eradicated in 42 of the 48 patients (88%). Six had persistent infection which led to recurrence of symptoms and further surgery was successful in eliminating infection in four patients. These rates of success are similar to those of other comparable series. We conclude that protracted courses of intravenous antibiotic treatment may not be necessary in the management of the infected total knee replacement.

In addition, we analysed the microbiological, histological and serological results obtained at the time of re-implantation of the definitive prosthesis, but could not identify a single test which alone would accurately predict a successful outcome.