RESUMEN

Implant surface nanofiber (NF) coatings represent an alternative way to prevent/treat periprosthetic joint infection (PJI) via local drug release. We developed and characterized a coaxial erythromycin (EM)-doped PLGA/PCL-PVA NF coating. The purpose of this study was to determine the efficacy of EM-NF coatings (EM0, no EM, EM100 (100 mg/mL), and EM1000 (1000 mg/mL) wt/wt) in a rat PJI model. A strong bond of the EM-NF coating to the surface of titanium (Ti) pins was confirmed by in vitro mechanical testing. Micro-computed tomography (mCT) analysis showed that both EM100 and EM1000 NF effectively reduced periprosthetic osteolysis compared to EM0 at 8 and 16 weeks after implantation. Histology showed that EM100 and EM1000 coatings effectively controlled infection and enhanced periprosthetic new bone formation. The bone implant contact (BIC) of EM100 (35.08%) was higher than negative controls and EM0 (3.43% and 0%, respectively). The bone area fraction occupancy (BAFO) of EM100 (0.63 mm2) was greater than controls and EM0 (0.390 mm2 and 0.0 mm2, respectively). The BAFO of EM100 was higher than that of EM1000 (0.3 mm2). These findings may provide a basis for a new implant surface fabrication strategy aimed at reducing the risks of defective osseointegration and PJI.

Asunto(s)

RESUMEN

Background: Periprosthetic joint infection (PJI) following total knee arthroplasty is a serious complication lacking evidence-based diagnostic and treatment protocols, particularly in ruling out persisting infection before reimplantation. Methods: This retrospective analysis assessed the mid-term outcomes of 66 patients undergoing septic two-stage knee revision surgeries from 2007 to 2013, diagnosed as per the Musculoskeletal Infection Society criteria. After implant removal and antibiotic treatment, reimplantation decisions were based on either joint aspiration, blood counts, and clinical examination (group A) or an open biopsy (group B). Both groups underwent meticulous debridement and spacer exchange during the interim period. Results: Late re-infection occurred in 12.1% of all patients. In group A, 13.8% experienced late re-infection, with 14.3% in subgroup A1 and 13.3% in subgroup A2. In group B, 10% had a late re-infection. No significant difference in re-infection or complication rates was found between the groups. Conclusions: The study did not demonstrate the superiority of group B's approach of open biopsy over group A's joint aspiration, clinical examination, and blood counts in preventing re-infection or reducing complications.

RESUMEN

PURPOSE: To determine the superior spacer design, a growing number of studies are comparing treatment results between patients having been treated with articulating and static knee spacers in the setting of two-stage revision for periprosthetic joint infection (PJI). In contrast, the primary objective of this study was to compare preoperative characteristics between patients from both spacer groups and examine whether significant differences were present prior to spacer implantation. METHODS: This retrospective, single-centre, cohort study examined the preoperative situation of 80 consecutive knee PJIs between 2017 and 2020. All patients underwent two-stage revision, with 35 (44%) receiving an articulating and 45 (56%) a static spacer. RESULTS: No significant differences were observed in terms of patient gender (p = 0.083), age (p = 0.666), comorbidity (p = 0.1) and preoperative clinical function (p = 0.246). Static spacers were significantly more often used in the presence of a periarticular fistula (p = 0.033), infection of a revision implant (p < 0.001), higher degree of bone loss (p < 0.001) and infection caused by a difficult-to-treat pathogen (p = 0.038). Complication and revision rates were similar for both spacer types during the interim period, while patients with articulating spacers demonstrated a superior clinical function (p < 0.001) during the interim period and after reimplantation. CONCLUSION: Static spacers are being utilised in significantly more complex and unfavourable preoperative scenarios. Therefore, a preoperative selection bias may be at least partially accountable for any disparities observed in postoperative outcomes. To achieve the best possible results, surgeons should know and respect the distinct indications of static and articulating spacers and consequently understand and use them as complementary surgical options. LEVEL OF EVIDENCE: Level III.

Asunto(s)

RESUMEN

Periprosthetic joint infection (PJI) is a serious complication after joint arthroplasty. PJI screening and conventional cultures may be inconclusive. Sonication fluid culturing stands out as a valuable adjunct technique for PJI diagnosis. This study aims to determine the clinical relevance of routine sonication for all (a)septic revisions. All patients who underwent (partial) hip or knee revision arthroplasty between 2012 and 2021 were retrospectively reviewed. We formed three groups based on the European Bone and Joint Society PJI criteria: infection confirmed, likely, and unlikely. We analyzed clinical, laboratory, and radiological screening. Sensitivity and specificity were calculated for synovial fluid (preoperative), tissue, and sonication fluid cultures. We determined the clinical relevance of sonication as the percentage of patients for whom sonication confirmed PJI; 429 patients who underwent (partial) revision of hip or knee arthroplasty were included. Sensitivity and specificity were 69% and 99% for synovial fluid cultures, 76% and 92% for tissue cultures, and 80% and 89% for sonication fluid cultures, respectively. Sonication fluid cultures improved tissue culture sensitivity and specificity to 83% and 99%, respectively. In 11% of PJIs, sonication fluid cultures were decisive for diagnosis. This is applicable to acute and chronic infections. Sonication fluid cultures enhanced the sensitivity and specificity of PJI diagnostics. In 11% of PJI cases, causative pathogens were confirmed by sonication fluid culture results. Sonication fluid culture should be performed in all revision arthroplasties.

RESUMEN

BACKGROUND: Periprosthetic joint infections (PJIs) of total hip arthroplasty (THA) or total knee arthroplasty (TKA) may occur in the setting of an uninfected ipsilateral prosthetic joint. However, the risk to that uninfected ipsilateral joint is unknown. We analyzed the survivorship free from PJI in at risk THAs and TKAs following treatment of an ipsilateral knee or hip PJI, respectively. METHODS: Using our institutional total joint registry, we identified 205 patients who underwent treatment for PJI (123 THAs and 83 TKAs) with an at-risk ipsilateral in situ knee or hip, respectively, between 2000 and 2019. In total, 54% of index PJIs were chronic and 46% were acute. The mean age was 70 years, 47% were female, and the mean body mass index was 32. Kaplan-Meier survivorship analyses were performed. Mean follow-up was 6 years. RESULTS: The 5-year survivorship free of PJI in an at-risk THA after an ipsilateral TKA was treated for PJI was 97%. The 5-year survivorship free of PJI in an at-risk TKA when the ipsilateral THA was treated for PJI was 99%. Three PJIs occurred (2 THAs and 1 TKA), all over 1 year from the index ipsilateral PJI treatment. One hip PJI was an acute hematogenous infection that resulted from pneumonia. The other 2 new PJIs were caused by the same organism as the index PJI and were due to a failure of source control at the index joint. CONCLUSIONS: When diagnosed with PJI in a single joint, the risk of developing PJI in an ipsilateral prosthetic joint within 5 years was low (1 to 3% risk). In the rare event of an ipsilateral infection, all occurred greater than one year from the index PJI and 2 of 3 were with the same organism when source infection control failed. LEVEL OF EVIDENCE: Prognostic Level III.

Asunto(s)

RESUMEN

BACKGROUND: Synovial calprotectin is a promising biomarker for diagnosing chronic periprosthetic joint infections (PJIs), but its diagnostic value has not been directly compared to synovial leukocyte count and polymorphonuclear neutrophils. This study aimed to: (1) evaluate and compare the diagnostic accuracy between these markers in patients undergoing revision arthroplasty for chronic PJI or aseptic reasons; and (2) determine the best rule-out and rule-in test for PJI. METHODS: Synovial fluid samples from patients undergoing revision arthroplasty in hip and knee joints were collected and analyzed. Patients diagnosed with an acute PJI, patients treated with antibiotics 2 weeks prior to revision surgery, and/or patients who had active inflammatory joint disease were excluded. Periprosthetic joint infections were diagnosed based on the presence of a sinus tract and/or positive intraoperative cultures according to the European Bone and Joint Infection Society microbiological criteria. RESULTS: A total of 137 patients were included, of whom 19 (14%) were diagnosed with a PJI. Overall, synovial calprotectin had the highest diagnostic accuracy of all studied markers (area under the curve 96%). Synovial calprotectin, with a cutoff of 50 mg/L, had the highest negative predictive value of 100%. However, PMNs (> 80%) combined with a leukocyte count (> 3,000 cells/µL) showed the highest positive likelihood ratio of an infection (PLR 17). CONCLUSIONS: Synovial calprotectin is the most accurate biomarker for ruling out a chronic PJI, while the combination of synovial leukocyte count and PMN is most reliable for ruling in a chronic PJI.

Asunto(s)

RESUMEN

Periprosthetic hip infection caused by Brucella abortus is rare and only a few cases have been reported. This current case report presents a case of a man in his early 50s who developed periprosthetic hip infection 2 years after right hip arthroplasty. There was no fever or pain, the usual cardinal signs of infection, except for a sinus tract at the previous surgical incision. Laboratory and arthrocentesis culture examinations (done twice) confirmed infection with B. abortus. Accordingly, a two-stage revision surgery was performed accompanied by antibiotic treatment with doxycycline and rifampicin after each stage. There was no recurrence at the 2-year follow-up, with good functional recovery of the hip joint. Clinically, this case serves to highlight the fact that periprosthetic hip infections caused by B. abortus might not present with the typical symptoms such as fever or hip pain. Furthermore, this current case involved a chronic sinus tract, so the diagnostic and therapeutic course of this case offers useful insights for managing similar cases in the future. In addition, a review of the literature on the diagnosis and treatment of Brucella-caused periprosthetic hip infection is presented.

Asunto(s)

RESUMEN

Introduction: The study investigated the utilization of odor detection dogs to identify the odor profile of Staphylococcus aureus (S. aureus) biofilms in pure in vitro samples and in in vivo biosamples from animals and humans with S. aureus periprosthetic joint infection (PJI). Biofilms form when bacterial communities aggregate on orthopedic implants leading to recalcitrant infections that are difficult to treat. Identifying PJI biofilm infections is challenging, and traditional microbiological cultures may yield negative results even in the presence of clinical signs. Methods: Dogs were trained on pure in vitro S. aureus biofilms and tested on lacrimal fluid samples from an in vivo animal model (rabbits) and human patients with confirmed S. aureus PJI. Results: The results demonstrated that dogs achieved a high degree of sensitivity and specificity in detecting the odor profile associated with S. aureus biofilms in rabbit samples. Preliminary results suggest that dogs can recognize S. aureus volatile organic compounds (VOCs) in human lacrimal fluid samples. Discussion: Training odor detection dogs on in vitro S. aureus, may provide an alternative to obtaining clinical samples for training and mitigates biosecurity hazards. The findings hold promise for culture-independent diagnostics, enabling early disease detection, and improved antimicrobial stewardship. In conclusion, this research demonstrates that dogs trained on in vitro S. aureus samples can identify the consistent VOC profile of PJI S. aureus biofilm infections. The study opens avenues for further investigations into a retained VOC profile of S. aureus biofilm infection. These advancements could revolutionize infectious disease diagnosis and treatment, leading to better patient outcomes and addressing the global challenge of antimicrobial resistance.

RESUMEN

BACKGROUND: Periprosthetic joint infection (PJI) following unicompartmental knee replacement (UKR) is an uncommon, yet serious, complication. There is a paucity of evidence regarding the effectiveness of Debridement-Antibiotics-and-Implant-Retention (DAIR) in this setting. The aim of this study is to investigate the effectiveness of DAIR for acute UKR PJI. METHOD: Between 2006 and 2019, 5195 UKR were performed at our institution. Over this period, sixteen patients underwent DAIR for early, acute PJI. All patients met MSIS PJI diagnostic criteria. The median age at DAIR was 67 years (range 40-73) and 12 patients were male (75.0%). The median time to DAIR was 24 days (range 6-60). Patients were followed up for a median of 6.5 years (range1.4-10.5) following DAIR. RESULTS: 0.3% (16/5195) of UKR in our institution had a DAIR within 3 months. 15 of 16 patients (93.8%) were culture positive, with the most common organism MSSA (n = 8, 50.0%). Patients were treated with an organism-specific intravenous antibiotic regime for a median of 6 weeks, followed by oral antibiotics for a median duration of 6 months. The Kaplan-Meier survivor estimate for revision for PJI was 57% (95%CI: 28-78%) at five years, and survivor estimate for all cause revision 52% (95%CI: 25-74%).The median Oxford Knee Score for patients with a viable implant at final follow-up was 45 points (range 39-46). CONCLUSION: Early, acute PJI after UKR is rare. DAIR had a moderate success rate, with infection-free survivorship of 57% at 5 years. Those successfully treated with DAIR had excellent functional outcome and implant survival.

Asunto(s)

RESUMEN

Identification and diagnosis of periprosthetic joint infection (PJI) are challenging, requiring a multi-disciplinary approach involving clinical evaluation, laboratory tests, and imaging studies. MRI is advantageous to alternative imaging techniques due to superior soft tissue contrast and absence of ionizing radiation. However, the presence of metallic implants can cause signal loss and artifacts. Metal artifact suppression (MARS) MRI techniques have been developed that mitigate metal artifacts and improve periprosthetic soft tissue visualization. This paper provides a review of the various MARS MRI techniques, their clinical applicability and accuracy in PJI diagnosis and evaluation, and current challenges and future perspectives.

RESUMEN

BACKGROUND: The aims of this study are as follows: (1) to investigate the level and probability of bacterial contamination on scrub suits over time for medical personnel working inside and/or outside the operating room (OR) area; (2) to discuss the protective role of cover gowns against bacterial contamination; and (3) to consider the necessity of changing into clean suits whenever entering the OR in terms of preventing periprosthetic joint infection (PJI) in total joint replacement (TJR). METHODS: The bacterial colony count was examined on the chest area of the scrub suits worn during various daily clinical practices. The genus/species of the contaminants were identified by matrix-assisted laser deposition ionization-time of flight mass spectrometry (MALDI-TOF MS). RESULTS: The scrub suits worn outside the OR area showed a greater level of bacterial contamination than those worn inside the OR area, although the colony counts tended to increase over time both in and out of the area. The probability of contamination involving coagulase-negative staphylococci (CNS) (known as the primary cause of PJI) did not increase significantly in the scrubs worn inside the OR area, but did increase significantly after a long-time departure from the OR area. CONCLUSIONS: Our results suggest that wearing scrub suits outside and/or the long duration of wearing the same suits can significantly increase the level and probability of any bacterial contamination (including CNS) on scrub suits. We also found that wearing a cover gown over scrub suits outside the OR area may have only a limited protective role against bacterial contamination.

RESUMEN

Purpose: The treatment of periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is still under debate. Two-stage exchange arthroplasty is the most common surgical procedure performed. This study analyzed a new functional articulating hip spacer called "Spaceflex" regarding the mechanical-related complications, the recurrent/persistent infection during the interval period, the overall infection-free survivorship after reimplantation, the overall complication/reoperation after reimplantation and the evaluation of patient-reported outcome measures (PROMs) at three intervals of time: before the first stage, during the interval period, and at the final follow-up after reimplantation. Methods: A consecutive series of 56 patients with chronic hip PJI undergoing two-stage prosthetic revision using a new intraoperatively molded articulating hip spacer design implanted by the same experienced surgeons was examined from January 2017 to December 2021. The demographic and clinical characteristics of the included patients were analyzed. Specifically, PROMs before the first stage, during the interval period, and at the final follow-up after reimplantation and complications reported during the interval period and after reimplantation were examined. Results: The new functional articulating hip spacer was characterized by a low mechanical complication rate (5.8%) and an overall two-stage procedure success rate of 90.6% at the last follow-up. PROMs improved with the spacer during the interval period and at the final follow-up. Furthermore, the reinfection rate was in line with other case series with different spacer designs. Finally, low postoperative complication rates after reimplantation have been demonstrated. Conclusions: Two-stage revision performed with a modular articulating spacer allows patients to preserve satisfactory functional and quality-of-life outcomes in the postoperative period, with a low risk of mechanical complications and without increasing the reinfection rate.

RESUMEN

BACKGROUND: Machine learning is a promising and powerful technology with increasing use in orthopedics. Periprosthetic joint infection following total knee arthroplasty results in increased morbidity and mortality. This systematic review investigated the use of machine learning in preventing periprosthetic joint infection. METHODS: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed was searched in November 2022. All studies that investigated the clinical applications of machine learning in the prevention of periprosthetic joint infection following total knee arthroplasty were included. Non-English studies, studies with no full text available, studies focusing on non-clinical applications of machine learning, reviews and meta-analyses were excluded. For each included study, its characteristics, machine learning applications, algorithms, statistical performances, strengths and limitations were summarized. Limitations of the current machine learning applications and the studies, including their 'black box' nature, overfitting, the requirement of a large dataset, the lack of external validation, and their retrospective nature were identified. RESULTS: Eleven studies were included in the final analysis. Machine learning applications in the prevention of periprosthetic joint infection were divided into four categories: prediction, diagnosis, antibiotic application and prognosis. CONCLUSION: Machine learning may be a favorable alternative to manual methods in the prevention of periprosthetic joint infection following total knee arthroplasty. It aids in preoperative health optimization, preoperative surgical planning, the early diagnosis of infection, the early application of suitable antibiotics, and the prediction of clinical outcomes. Future research is warranted to resolve the current limitations and bring machine learning into clinical settings.

RESUMEN

The incidence of periprosthetic joint infections (PJIs) is ~2% of total procedures and it is expected to rise due to an ageing population. Despite the large burden PJI has on both the individual and society, the immune response to the most commonly isolated pathogens, i.e., Staphylococcus aureus and Staphylococcus epidermidis, remains incompletely understood. In this work, we integrate the analysis of synovial fluids from patients undergoing hip and knee replacement surgery with in-vitro experimental data obtained using a newly developed platform, mimicking the environment of periprosthetic implants. We found that the presence of an implant, even in patients undergoing aseptic revisions, is sufficient to induce an immune response, which is significantly different between septic and aseptic revisions. This difference is confirmed by the presence of pro- and anti-inflammatory cytokines in synovial fluids. Moreover, we discovered that the immune response is also dependent on the type of bacteria and the topography of the implant surface. While S. epidermidis seems to be able to hide better from the attack of the immune system when cultured on rough surfaces (indicative of uncemented prostheses), S. aureus reacts differently depending on the contact surface it is exposed to. The experiments we performed in-vitro also showed a higher biofilm formation on rough surfaces compared to flat ones for both species, suggesting that the topography of the implant could influence both biofilm formation and the consequent immune response.

Asunto(s)

RESUMEN

BACKGROUND: Modular fluted tapered stems (MFTSs) are commonly used in revision total hip arthroplasty (THA) and provide the option of exchanging the proximal modular portion to address future surgical problems without complete femoral revision. We are unaware of any data documenting the frequencies, indications, and outcomes of modular proximal body exchange in re-revision THA. METHODS: Between 1997 and 2019, we performed 57 modular proximal body exchanges among 8,079 revision THAs at our institution. Indications and outcomes were documented at a mean follow-up of 3.4 years (range, 0 to 12.8). RESULTS: Modular proximal body exchange was performed on 47 of 1,375 (3%) of MFTSs implanted. The indications for all 57 modular proximal body exchanges performed during the study period were dislocation in 30 (53%), partial resection for periprosthetic joint infection (PJI) in 13 (23%), modular junction failure in 8 (14%), surgical exposure in 4 (7%), and concurrently with trochanteric osteotomy nonunion fixation in 2 (4%). At the final follow-up, subsequent re-revisions occurred in 10 of 30 (33%) of modular proximal body exchanges indicated for dislocation and in 5 of 13 of those indicated for PJI. One modular junction subsequently fractured after modular proximal body exchange. CONCLUSION: Modular proximal body exchange of a MFTS is an uncommon procedure most often performed for treatment of hip dislocation or PJI. It is moderately successful with approximately one-third of cases requiring subsequent re-revision. This procedure is often performed with modular component exchange alone, but can also be helpful to facilitate complex acetabular exposure. These data provide useful information to surgeons and patients undergoing this procedure. LEVEL OF EVIDENCE: IV.

Asunto(s)

RESUMEN

AIMS: The aim of this study was to evaluate the optimal deep tissue specimen sample number for histopathological analysis in the diagnosis of periprosthetic joint infection (PJI). METHODS: In this retrospective diagnostic study, patients undergoing revision surgery after total hip or knee arthroplasty (n = 119) between January 2015 and July 2018 were included. Multiple specimens of the periprosthetic membrane and pseudocapsule were obtained for histopathological analysis at revision arthroplasty. Based on the Infectious Diseases Society of America (IDSA) 2013 criteria, the International Consensus Meeting (ICM) 2018 criteria, and the European Bone and Joint Infection Society (EBJIS) 2021 criteria, PJI was defined. Using a mixed effects logistic regression model, the sensitivity and specificity of the histological diagnosis were calculated. The optimal number of periprosthetic tissue specimens for histopathological analysis was determined by applying the Youden index. RESULTS: Based on the EBJIS criteria (excluding histology), 46 (39%) patients were classified as infected. Four to six specimens showed the highest Youden index (four specimens: 0.631; five: 0.634; six: 0.632). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of five tissue specimens were 76.5% (95% confidence interval (CI) 67.6 to 81.4), 86.8% (95% CI 81.3 to 93.5), 66.0% (95% CI 53.2 to 78.7), and 84.3% (95% CI 79.4 to 89.3), respectively. The area under the curve (AUC) was calculated with 0.81 (as a function of the number of tissue specimens). Applying the ICM and IDSA criteria (excluding histology), 40 (34%) and 32 (27%) patients were categorized as septic. Three to five specimens had the highest Youden index (ICM 3: 0.648; 4: 0.651; 5: 0.649) (IDSA 3: 0.627; 4: 0.629; 5: 0.625). CONCLUSION: Three to six tissue specimens of the periprosthetic membrane and pseudocapsule should be collected at revision arthroplasty and analyzed by a pathologist experienced and skilled in interpreting periprosthetic tissue.Cite this article: Bone Joint J 2023;105-B(2):158-165.

Asunto(s)

RESUMEN

AIMS: This study aimed to explore the diagnostic value of synovial fluid neutrophil extracellular traps (SF-NETs) in periprosthetic joint infection (PJI) diagnosis, and compare it with that of microbial culture, serum ESR and CRP, synovial white blood cell (WBC) count, and polymorphonuclear neutrophil percentage (PMN%). METHODS: In a single health centre, patients with suspected PJI were enrolled from January 2013 to December 2021. The inclusion criteria were: 1) patients who were suspected to have PJI; 2) patients with complete medical records; and 3) patients from whom sufficient synovial fluid was obtained for microbial culture and NET test. Patients who received revision surgeries due to aseptic failure (AF) were selected as controls. Synovial fluid was collected for microbial culture and SF-WBC, SF-PNM%, and SF-NET detection. The receiver operating characteristic curve (ROC) of synovial NET, WBC, PMN%, and area under the curve (AUC) were obtained; the diagnostic efficacies of these diagnostic indexes were calculated and compared. RESULTS: The levels of SF-NETs in the PJI group were significantly higher than those of the AF group. The AUC of SF-NET was 0.971 (95% confidence interval (CI) 0.903 to 0.996), the sensitivity was 93.48% (95% CI 82.10% to 98.63%), the specificity was 96.43% (95% CI 81.65% to 99.91%), the accuracy was 94.60% (95% CI 86.73% to 98.50%), the positive predictive value was 97.73%, and the negative predictive value was 90%. Further analysis showed that SF-NET could improve the diagnosis of culture-negative PJI, patients with PJI who received antibiotic treatment preoperatively, and fungal PJI. CONCLUSION: SF-NET is a novel and ideal synovial fluid biomarker for PJI diagnosis, which could improve PJI diagnosis greatly.Cite this article: Bone Joint Res 2023;12(2):113-120.

RESUMEN

AIMS: Arthroplasty surgery of the knee and hip is performed in two to three million patients annually. Periprosthetic joint infections occur in 4% of these patients. Debridement, antibiotics, and implant retention (DAIR) surgery aimed at cleaning the infected prosthesis often fails, subsequently requiring invasive revision of the complete prosthetic reconstruction. Infection-specific imaging may help to guide DAIR. In this study, we evaluated a bacteria-specific hybrid tracer (99mTc-UBI29-41-Cy5) and its ability to visualize the bacterial load on femoral implants using clinical-grade image guidance methods. METHODS: 99mTc-UBI29-41-Cy5 specificity for Stapylococcus aureus was assessed in vitro using fluorescence confocal imaging. Topical administration was used to highlight the location of S. aureus cultured on femoral prostheses using fluorescence imaging and freehand single photon emission CT (fhSPECT) scans. Gamma counting and fhSPECT were used to quantify the bacterial load and monitor cleaning with chlorhexidine. Microbiological culturing helped to relate the imaging findings with the number of (remaining) bacteria. RESULTS: Bacteria could be effectively stained in vitro and on prostheses, irrespective of the presence of biofilm. Infected prostheses revealed bacterial presence on the transition zone between the head and neck, and in the screw hole. Qualitative 2D fluorescence images could be complemented with quantitative 3D fhSPECT scans. Despite thorough chlorhexidine treatments, 28% to 44% of the signal remained present in the locations of the infection that were identified using imaging, which included 500 to 2,000 viable bacteria. CONCLUSION: The hybrid tracer 99mTc-UBI29-41-Cy5 allowed effective bacterial staining. Qualitative real-time fluorescence guidance could be effectively combined with nuclear imaging that enables quantitative monitoring of the effectiveness of cleaning strategies.Cite this article: Bone Joint Res 2023;12(1):72-79.

RESUMEN

INTRODUCTION: Although intra-articular injections (IAIs) serve as the first-line non-surgical management for severe osteoarthritis (OA), recent analyses have suggested they are associated with an increased infection risk following primary total hip arthroplasty (THA). Therefore, our systematic review and meta-analysis explored the relationship between IAIs and periprosthetic joint infection (PJI) following THA reported in the current literature. METHODS: Five online databases were queried for analyses published from January 1st, 2000-May 1st, 2021 reporting on PJI rates between patients undergoing primary THA who did and did not preoperatively receive an IAI. The overall pooled effect of injection status on PJI incidence was determined using Mantel-Haenszel (M-H) models. This was similarly conducted for segregated preoperative intervals: 0-3 months, > 3-6 months, > 6 + months. RESULTS: A total of 11 articles were included in our analysis reporting on 278,782 THAs (IAI: n = 41,138; no IAI: n = 237,644). Patients receiving pre-operative injections had a significantly higher risk of PJI (OR: 1.31, 95% CI 1.07-1.62; p = 0.009). However, this finding was not robust. IAI receipt within 3-months of THA was associated with significantly higher PJI rates (OR: 1.68, 95% CI 1.48-1.90; p < 0.001). However, no significant difference was demonstrated in the > 3-6 month (OR: 1.19, 95% CI 0.94-1.52; p = 0.16) and > 6 + month sub-analyses (OR: 1.20, 95% CI 0.96-1.50; p = 0.11). The results of all sub-analyses remained were robust. DISCUSSION: Our findings suggest that patients requiring THA should wait at least 3-months following IAI to reduce post-operative infection risk. This information can help inform patients considering OA management options, as well as adult reconstruction surgeons during preoperative optimization.

Asunto(s)