Periprosthetic joint infection (PJI) represents a complex challenge in orthopaedic surgery associated with substantial morbidity and healthcare expenditures. The debridement, antibiotics, and implant retention (DAIR) protocol is a viable treatment, offering several advantages over exchange arthroplasty. With the evolution of treatment strategies, considerable efforts have been directed towards enhancing the efficacy of DAIR, including the development of a phased debridement protocol for acute PJI management. This article provides an in-depth analysis of DAIR, presenting the outcomes of single-stage, two-stage, and repeated DAIR procedures. It delves into the challenges faced, including patient heterogeneity, pathogen identification, variability in surgical techniques, and antibiotics selection. Moreover, critical factors that influence the decision-making process between single- and two-stage DAIR protocols are addressed, including team composition, timing of the intervention, antibiotic regimens, and both anatomical and implant-related considerations. By providing a comprehensive overview of DAIR protocols and their clinical implications, this annotation aims to elucidate the advancements, challenges, and potential future directions in the application of DAIR for PJI management. It is intended to equip clinicians with the insights required to effectively navigate the complexities of implementing DAIR strategies, thereby facilitating informed decision-making for optimizing patient outcomes.

Cite this article: Bone Joint J 2024;106-B(12):1377–1384.

Aims

The use of cementless total knee arthroplasty (TKA) components has increased during the past decade. The initial design of cementless metal-backed patellar components had shown high failure rates due to many factors. The aim of this study was to evaluate the clinical results of a second-generation cementless, metal-backed patellar component of a modern design.

Aims

The tibial component of total knee arthroplasty can either be an all-polyethylene (AP) implant or a metal-backed (MB) implant. This study aims to compare the five-year functional outcomes of AP tibial components to MB components in patients aged over 70 years. Secondary aims are to compare quality of life, implant survivorship, and cost-effectiveness.

Aims

Metal allergy in knee arthroplasty patients is a controversial topic. We aimed to conduct a scoping review to clarify the management of metal allergy in primary and revision total knee arthroplasty (TKA).

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

To describe the risk of periprosthetic joint infection (PJI) and reoperation in patients who have an acute, traumatic wound dehiscence following total knee arthroplasty (TKA).

Aims

Ideal component sizing may be difficult to achieve in unicompartmental knee arthroplasty (UKA). Anatomical variants, incremental implant size, and a reduced surgical exposure may lead to over- or under-sizing of the components. The purpose of this study was to compare the accuracy of UKA sizing with robotic-assisted techniques versus a conventional surgical technique.

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

We propose a state-of-the-art temporary spacer, consisting of a cobalt-chrome (CoCr) femoral component and a gentamicin-eluting ultra-high molecular weight polyethylene (UHMWPE) tibial insert, which can provide therapeutic delivery of gentamicin, while retaining excellent mechanical properties. The proposed implant is designed to replace conventional spacers made from bone cement.

Aims. We aimed to examine the long-term mechanical survivorship, describe the modes of all-cause failure, and identify risk factors for mechanical failure of all-polyethylene tibial components in endoprosthetic reconstruction. Methods. This is a retrospective database review of consecutive endoprosthetic reconstructions performed for oncological indications between 1980 and 2019. Patients with all-polyethylene tibial components were isolated and analyzed for revision for mechanical failure. Outcomes included survival of the all-polyethylene tibial component, revision surgery categorized according to the Henderson Failure Mode Classification, and complications and functional outcome, as assessed by the Musculoskeletal Tumor Society (MSTS) score at the final follow-up. Results. A total of 278 patients were identified with 289 all-polyethylene tibial components. Mechanical survival was 98.4%, 91.1%, and 85.2% at five, ten and 15 years, respectively. A total of 15 mechanical failures were identified at the final follow-up. Of the 13 all-polyethylene tibial components used for revision of a previous tibial component, five (38.5%) failed mechanically. Younger patients (< 18 years vs > 18 years; p = 0.005) and those used as revision components (p < 0.001) had significantly increased rates of failure. Multivariate logistic regression modelling showed revision status to be a positive risk factor for failure (odds ratio (OR) 19.498, 95% confidence interval (CI) 4.598 to 82.676) and increasing age was a negative risk factor for failure (OR 0.927, 95% CI 0.872 to 0.987). Age-stratified risk analysis showed that age > 24 years was no longer a statistically significant risk factor for failure. The final mean MSTS score for all patients was 89% (8.5% to 100.0%). Conclusion. The long-term mechanical survivorship of all-polyethylene tibial components when used for tumour endoprostheses was excellent. Tumour surgeons should consider using these components for their durability and the secondary benefits of reduced cost and ease of removal and revision. However, caution should be taken when using all-polyethylene tibial components in the revision setting as a significantly higher rate of mechanical failure was seen in this group of patients. Cite this article: Bone Joint J. 2020;102-B(2):170–176

Aims

Limited evidence is available on mid-term outcomes of robotic-arm assisted (RA) partial knee arthroplasty (PKA). Therefore, the purpose of this study was to evaluate mid-term survivorship, modes of failure, and patient-reported outcomes of RA PKA.

Implant selection in TKA remains highly variable. Surgeons consider pre-operative deformity, patient factors such as BMI and bone quality, surgical experience, retention or substitution for the PCL, type of articulation and polyethylene, cost, and fixation with or without cement. We have most frequently implanted the same implant for the majority of patients. This is based on the fact that multiple large series of TKAs have demonstrated that the most durable TKAs have been non-modular metal-backed tibial components, retention of the PCL, with a cemented all-polyethylene patellar component. Polymer wear must be addressed for long-term durability. One method for reducing polyethylene wear is eliminating modularity between a metal-backed tray and the articular bearing surface. This can be done with a metal-backed implant as with the IB-1, AGC, Vanguard Mono-lock, or with elimination of the metal backing via a one piece all-polyethylene tibial component. The all-polyethylene implants appear design and patient sensitive. We observed higher clinical failure rates in a flat-on-flat design. Other authors have observed improved survivorship with coronal dishing of the articular surfaces which centralises osseous stresses. All-polyethylene implants have promise in the future but require proven design and fixation design features

Background. Total knee arthroplasty (TKA) overall is a very reliable, durable procedure. Biomechanical studies have suggested superior stress distribution in metal-backed tibial trays, however, these results have not been universally observed clinically. Currently, there is a paucity of information examining the survival and outcomes of all-polyethylene tibial components. Methods. We reviewed 31,939 patients undergoing a primary TKA over a 43-year period (1970–2013). There were 28,224 (88%) metal-backed and 3,715 (12%) all-polyethylene tibial components. The metal-backed and all-polyethylene groups had comparable demographics with respect to sex distribution (57% female for both), mean age (67 vs. 71 years), and mean BMI (31.6 vs. 31.1). Mean follow-up was 7 years (maximum 40 years). Results. The purpose of this investigation was to analyze the outcomes of all-polyethylene compared to metal-backed components in TKA and to determine: (1) is there a difference in overall survival? All-polyethylene tibial components had improved survivorship (P<0.0001) and metal-backed tibias were at increased risk of revision (HR 3.41, P<0.0001); (2) Does body mass index (BMI) or age have an effect on survival of all-polyethylene compared to metal-backed tibial components? All-polyethylene tibias had improved survival (P<0.01) in all age groups except in patients 85 years or greater, where there was no difference (P=0.16). All-polyethylene tibial components had improved survival (P<0.005) for all BMIs except in the morbidly obese (BMI ≥40) where there was no difference (P=0.20); (3) Is there an increased risk of post-operative infection? Metal-backed tibial components were found to have an increased risk of infection (HR 1.60, P=0.003); (4) Is there a difference in the rate of reoperation and post-operative complications? Metal-backed tibial components were found to have an increased risk of reoperation (HR 1.84, P<0.0001). Conclusions. The use of all-polyethylene tibias should be considered for the majority of patients, regardless of age and BMI

Background. Total knee arthroplasty (TKA) overall is a very reliable, durable procedure. Biomechanical studies have suggested superior stress distribution in metal-backed tibial trays, however, these results have not been universally observed clinically. Currently, there is a paucity of information examining the survival and outcomes of all-polyethylene tibial components. Methods. We reviewed 31,939 patients undergoing a primary TKA over a 43-year period (1970–2013). There were 28,224 (88%) metal-backed and 3,715 (12%) all-polyethylene tibial components. The metal-backed and all-polyethylene groups had comparable demographics with respect to sex distribution (57% female for both) mean age (67 vs. 71 years), and mean BMI (31.6 vs. 31.1). Mean follow-up was 7 years (maximum 40 years). Results. The purpose of this investigation was to analyze the outcomes of all-polyethylene compared to metal-backed components in TKA and to determine (1) is there a difference in overall survival? All polyethylene tibial components had improved survivorship (P<0.0001) and metal-backed tibias were at increased risk of revision (HR 3.41, P<0.0001). (2) Does body mass index (BMI) or age have an effect on survival of all-polyethylene compared to metal-backed tibial components? All-polyethylene tibias had improved survival (P<0.01) in all ages groups except in patients 85 years or greater, where there was no difference (P=0.16). All-polyethylene tibial components had improved survival (P<0.005) for all BMI's except in the morbidly obese (BMI ≥40) where there was no difference (P=0.20). (3) Is there an increased risk of post-operative infection? Metal-backed tibial components were found to have an increased risk of infection (HR 1.60, P=0.003). (4) Is there a difference in the rate of reoperation and post-operative complications? Metal-backed tibial components were found to have an increased risk of reoperation (HR 1.84, P<0.0001). Conclusions. The use of all-polyethylene tibias should be considered for the majority of patients, regardless of age and BMI

Two big problems exist with the all-polyethylene cemented tibial component; the polyethylene and the cement. The polyethylene is too weak and flexible to bear high tibial load, so it deforms and loosens. The interface stresses are too high when two flexible structures are poorly bonded and heavily loaded. Modularity between the polyethylene tibial component and the metal-backed tray was introduced in the mid-80's for versatility and to facilitate screw fixation for cementless implants. These designs allow exchange of various polyethylene thicknesses, and aids the addition of stems and wedges. Other advantages include the reduction of inventory, and the potential for isolated tibial polyethylene exchanges as a simpler revision procedure. Several studies have documented the high failure rate of isolated polyethylene exchange procedures, because technical problems related to the original components are left uncorrected. However, revision for wear is the simplest revision ever!. Since the late 1980's the phenomena of polyethylene wear and osteolysis has been observed much more frequently when compared with earlier eras. The reasons for this increased prevalence of synovitis, progressive osteolysis, and severe polyethylene wear remain unclear. There is some association with the widespread use of both cementless and cemented modular tibial designs. Improved polyethylene attachment is the answer even if a screw, a wire, or a pin is needed. Do not abandon the module tibia

Background: Total knee arthroplasty (TKA) overall is a very reliable, durable procedure. Biomechanical studies have suggested superior stress distribution in metal-backed tibial trays, however, these results have not been universally observed clinically. Currently, there is a paucity of information examining the survival and outcomes of all-polyethylene tibial components. Methods: We reviewed 31,939 patients undergoing a primary TKA over a 43-year period (1970–2013). There were 28,224 (88%) metal-backed and 3,715 (12%) all-polyethylene tibial components. The metal-backed and all-polyethylene groups had comparable demographics with respect to sex distribution (57% female for both) mean age (67 vs. 71 years), and mean BMI (31.6 vs. 31.1). Mean follow-up was 7 years (maximum 40 years). Results: The purpose of this investigation was to analyze the outcomes of all-polyethylene compared to metal backed components in TKA and to determine (1) is there a difference in overall survival? All-polyethylene tibial components had improved survivorship (P<0.0001) and metal backed tibias were at increased risk of revision (HR 3.41, P<0.0001). (2) Does body mass index (BMI) or age have an affect on survival of all-polyethylene compared to metal-backed tibial components? All-polyethylene tibias had improved survival (P<0.01) in all ages groups except in patients 85 years or greater, where there was no difference (P=0.16). All-polyethylene tibial components had improved survival (P<0.005) for all BMI's except in the morbidly obese (BMI ≥40) where there was no difference (P=0.20). (3) Is there an increased risk of post-operative infection? Metal-backed tibial components were found to have an increased risk of infection (HR 1.60, P=0.003). (4) Is there a difference in the rate of reoperation and post-operative complications? Metal-backed tibial components were found to have an increased risk of reoperation (HR 1.84, P<0.0001). Conclusions: The use of all-polyethylene tibias should be considered for the majority of patients, regardless of age and BMI

Objectives

Up to 40% of unicompartmental knee arthroplasty (UKA) revisions are performed for unexplained pain which may be caused by elevated proximal tibial bone strain. This study investigates the effect of tibial component metal backing and polyethylene thickness on bone strain in a cemented fixed-bearing medial UKA using a finite element model (FEM) validated experimentally by digital image correlation (DIC) and acoustic emission (AE).

Two big problems exist with the all-polyethylene cemented tibial component; the polyethylene and the cement. The polyethylene is too weak and flexible to bear tibial load, so it deforms and loosens. The interface stresses are too high when two flexible structures are poorly bonded and heavily loaded. Modularity between the polyethylene tibial component and the metal-backed tray was introduced in the mid-1980s for versatility and to facilitate screw fixation for cementless implants. These designs allow exchange of various polyethylene thicknesses, and aid the addition of stems and wedges. Other advantages include the reduction of inventory, and the potential for isolated tibial polyethylene exchanges as a simpler revision procedure. Several studies have documented the high failure rate of isolated polyethylene exchange procedures, because technical problems related to the original components are left uncorrected. However, revision for wear is the simplest revision ever!. Since the late 1980s the phenomena of polyethylene wear and osteolysis have been observed much more frequently when compared with earlier eras. The reasons for this increased prevalence of synovitis, progressive osteolysis, and severe polyethylene wear remain unclear. There is some association with the widespread use of both cementless and cemented modular tibial designs. Improved polyethylene attachment is the answer even if a screw, a wire, or a pin is needed. Do not abandon the modular tibia on any patient

While the vast majority of total knee replacements performed throughout the world employ a modular metal-backed tibial tray, and not an all-polyethylene tray, this issue remains controversial. Proposed advantages to a metal-backed tray include: a) decreased bending strains, b) reduces compressive stresses in the cement and cancellous bone beneath the baseplate (especially in asymmetric loading), c) distributes load more evenly across the interface. Proposed advantages of an all-polyethylene tray include: a) cost reduction, b) reduced polyethylene thickness with the same amount of bone resection, c) increased tensile stresses at the interface during eccentric loading. The challenge is at present we don't know the >10-year track record of current generation tibial components. This debate centers on the <60-year-old. This is the most difficult patient in total knee arthroplasty with higher revision rates than an older cohort. It makes sense to use an all-polyethylene tibia if the revision rates turn out to be similar and you don't intend to do a polyethylene exchange in the future. It makes sense to do a modular tray if the results are similar, but there is an intention to do a polyethylene exchange in the future. If either one of these implants choices has a lower cumulative revision rate, then that is the implant of choice at present. However, we need to understand that at present we don't know if the results of current generation all-polyethylene tibial components will indeed be equal to metal-backed components. The most recent data from the Australian registry suggests that in fact all-polyethylene tibial components have a higher failure rate than metal-backed components when looking at the entire class of design. This would be expected to be even more significant in the younger patient