Native Septic Arthritis Research Articles

Injection drug use is associated with repeat irrigation and debridement in native joint septic arthritis

Background and objectiveSeptic arthritis is an orthopaedic emergency that requires prompt irrigation and debridement (I&D). Some patients require a repeat I&D, which poses excessive burden on the patient and provider. The goal of this study was to identify possible risk factors for repeat I&D in the setting of native septic arthritis. Materials and methodsConsecutive patients with a primary diagnosis of native joint septic arthritis from June 2014–November 2018 at two level-one trauma centers were retrospectively identified via billing codes. Patients were included if they had a clinical presentation consistent with native septic arthritis. Independent-sample T-tests, Fisher's Exact Tests, and multivariable logistic regression were performed to determine what risk factors for repeat I&D were statistically significant. ResultsTwo-hundred and twenty-one patients were identified, and 192 were included in the final analysis (36 % female, 64 % male, mean age 53 years). 231 joints were included in the analysis (knee, n = 115; hip, n = 53; shoulder, n = 37; other, n = 16). 29 % of septic joints were associated with injection drug use (IDU-SA). 30 % of IDU-SA cases required a repeat I&D compared to 17 % for non IDU-SA cases (p = 0.03). IDU-SA patients were associated with more total I&Ds compared to patients without IDU-SA (1.70 vs. 1.32; p = 0.048). This association remained significant when controlling for smoking history, diabetes, human immunodeficiency virus, immunocompromised status, and steroid use. ConclusionsIDU-SA was associated with repeat I&D. Physicians working with IDU-SA patients should alter postoperative surveillance standards and consider adopting a multimodal team approach to improve septic arthritis management.

TOTAL KNEE ARTHROPLASTY FOLLOWING SEPTIC ARTHRITIS: A LONGITUDINAL STUDY OVER 20 YEARS

ObjectivesPost-infective arthritis is an important sequalae of septic arthritis(SA). While total knee arthroplasty(TKA) is an effective treatment for said arthritis, previous SA brings challenges for treatment planning. Using prospectively collected data from a cohort of patients with knee SA, this study aims to determine the proportion of patients requiring eventual TKA, and risk factors of developing prosthetic joint Infection(PJI).MethodsAll cases of 1st episode knee SA from 01/01/2000 to 31/12/2020 were identified in the Auckland region. Patient records and NZJR records of all cases were searched to identify subsequent TKA. PJI following arthroplasty was identified using ICM criteria.Univariate and multivariate analysis was performed to determine risk factors for developing PJI.Results854 cases of native SA were identified. Of these, 71 (8.3%) progressed to TKA. Average time from completion of SA treatment to TKA was 3.8 years (SD 3.4). At an average follow-up of 7.8 years(1–19.6), 11(15.5%) developed PJI and required reoperation in the form of; DAIR (n =5), revision (n= 6). A further 4 were readmitted for superficial infections. Five-year and ten-year implant survival was 90.0% and 87.1%, significantly lower than average survival of TKA in the NZJR (97.3% at 5 years and 95.7% at 10). Average time between completion of SA treatment and TKA was 2.1 years in those developing PJI, vs 4.1 years in those who did not(p = 0.0019). 4.8% of cases developed PJI when TKA was performed >5 years after SA, compared with 20% risk of PJI within 5 years(p=0.16). Multivariate analysis showed no significant impact of pre-defined medical risk factors or demographic on outcomes.ConclusionA significant percentage of patients required TKA following knee SA. Time lapsed from SA treatment completion to TKA is an important risk factor for developing PJI.

The Effect of Crystal Arthropathy on the Diagnostic Criteria of Native Septic Arthritis.

Distinguishing between septic arthritis and crystal arthropathy flares can be challenging. The purpose of this study was to determine how the presence of synovial crystals affects the diagnostic criteria of septic arthritis. A retrospective review identified patients undergoing joint aspirations to rule out native septic arthritis. Differences between septic arthritis presenting with and without synovial crystals were analyzed. A receiver-operating characteristic curve was plotted for laboratory markers to determine the area under the curve, or diagnostic accuracy, for septic arthritis and to evaluate thresholds that maximized sensitivity and specificity. There were 302 joint aspirations in 267 patients. Septic arthritis was diagnosed in 17.9% (54/302). Patients with synovial crystals were less likely to have septic arthritis (4.2% [5/119] vs. 26.8% [49/183], P < 0.0001). Septic arthritis in patients with no synovial crystals was associated with fever and a higher synovial white blood cell (WBC) count, synovial polymorphonuclear cell percentage (PMN%), serum WBC, and C-reactive protein (CRP) ( P < 0.05). Septic arthritis in patients with synovial crystals was only associated with inability to bear weight and a higher synovial WBC and CRP ( P < 0.05). Synovial PMN% was considered nondiagnostic of septic arthritis (area under the curve 0.56) in patients with crystals while synovial WBC and CRP had acceptable (0.76) and excellent (0.83) diagnostic utility, respectively. The WBC and CRP value thresholds that maximized sensitivity and specificity for septic arthritis were greater in patients with crystals (21,600 vs. 17,954 cells/μL and 125 vs. 69 mg/L, respectively). The presence of synovial crystals reduced the likelihood of septic arthritis and altered the laboratory diagnostic criteria. PMN% was nondiagnostic in the setting of synovial crystals.

Associations with unplanned repeat irrigation and debridement of native septic arthritis.

To identify associations with unplanned repeat irrigation and debridement (I&D) after arthrotomy for native septic arthritis. A retrospective review identified patients with native septic arthritis treated with open arthrotomies. The primary outcome was unplanned repeat I&D within 90 days. Associations evaluated for included comorbidities, ability to bear weight, fever, immunosuppressed status, purulence, C-reactive protein, erythrocyte sedimentation rate, white blood cell count (synovial fluid and serum levels), and synovial fluid polymorphonuclear cell percentage (PMN%). There were 59 arthrotomies in 53 patients involving the knee (n = 32), shoulder (n = 10), elbow (n = 8), ankle (n = 6), and hip (n = 3). The median patient age was 52, and a 71.2% were male. An unplanned repeat I&D was required in 40.7% (n = 24). The median time to the second I&D was 4 days (interquartile range 3 to 9). On univariate analysis, unplanned repeat I&Ds were associated with fever (p = 0.03), purulence (p = 0.01), bacteria growth on cultures (p = 0.02), and the use of deep drains (p = 0.05). On multivariate analysis, the only variables that remained associated with unplanned repeat I&Ds were fever (odds ratio (OR) 5.5, 95% confidence interval (CI) 1.3, 23.6, p = 0.02) and purulence (OR 5.3, CI 1.1, 24.4, p = 0.03). An unplanned repeat I&D was required in 40.7% of patients and was associated with fever and purulence. These findings highlight the difficulty of controlling these infections and support the need for future research into better methods of management. Diagnostic, Level III.

First evaluation of a commercial multiplex PCR panel for rapid detection of pathogens associated with acute joint infections.

Background: prompt recognition and identification of the causative microorganism in acute septic arthritis of native and prosthetic joints is vital to increase the chances of successful treatment. The aim of this study was to independently assess the diagnostic accuracy of the multiplex BIOFIRE® Joint Infection (JI) Panel (investigational use only) in synovial fluid for rapid diagnosis. Methods: synovial fluid samples were collected at the University Medical Center Groningen from patients who had a clinical suspicion of a native septic arthritis, early acute (post-operative, within 3 months after arthroplasty) periprosthetic joint infection (PJI) or late acute (hematogenous, months after arthroplasty) PJI. JI Panel results were compared to infection according to Musculoskeletal Infection Society criteria and culture-based methods as reference standard. Results: a total of 45 samples were analysed. The BIOFIRE JI Panel showed a high specificity (100 %, 95 % confidence interval (CI): 78-100) in all patient categories. Sensitivity was 83 % (95 % CI: 44-97) for patients with a clinical suspicion of native septic arthritis ( ), 73 % (95 % CI: 48-89) for patients with a clinical suspicion of a late acute PJI ( ), and 30 % (95 % CI: 11-60) for patients with a clinical suspicion of an early acute PJI ( ). Conclusion: the results of this study indicate a clear clinical benefit of the BIOFIRE JI Panel in patients with a suspected native septic arthritis and late acute (hematogenous) PJI, but a low clinical benefit in patients with an early acute (post-operative) PJI due to the absence of certain relevant microorganisms, such as Staphylococcus epidermidis, from the panel.

1730. Real-World Use Of Dalbavancin In A US Tertiary Referral Center

Abstract Background Dalbavancin is a lipoglycopeptide with prolonged half-life currently approved for treatment of bacterial skin and soft tissue infections. Off-label uses of dalbavancin include multiple Gram-positive infections requiring long-term antibiotics use. However, clinical data regarding Dalbavancin use in the real-world setting remains limited. Methods We conducted a retrospective cohort study of all adult inpatients who were administered ≥1 dose of Dalbavancin between November 2017 and March 2022. Results Forty-nine adults were identified. Dalbavancin was used to treat skin/soft tissue infections in 9 patients (18.8%). Off-label uses accommodated for the majority of patients, with diagnoses included: bloodstream infection (24, 50%), osteomyelitis (9,18.8%), native valve infective endocarditis (6,12.5%), native septic arthritis (6,12.5%), epidural abscess (4,8.3%), catheter-related bacteremia (3,6.3%) prosthetic joint infection (3,6.3%), and diabetic foot infection (1,2.1%). No patients with prosthetic valve infective endocarditis were identified. Staphylococcus aureus was the most common treated pathogen: MRSA (15, 35.7%), MSSA (17, 40.5%). Other pathogens included: Streptococcus (2,4.8%), Enterococcus (4,9.5%), coagulase negative Staphylococcus (5,11.9%), other gram positive (4,9.5%), none (2,4.8%). Among patients who completed therapy, overall cure, and clinical response as assessed at day 42 was achieved in 29 (96.7%) of patients,1 patient (3.3%) had relapse due to noncompliance with antimicrobial suppressive regimen. Intravenous drug use was the most common cause among patients who did not complete treatment (10, 58.8%). Adverse events included mild elevation in liver function tests, which were reversible and were not definitively related to the treatment. No rashes or infusion related reaction were reported. There were no adverse events resulting in drug discontinuation. Conclusion Real-world, including off-label, use of Dalbavancin appears safe and is associated with favorable treatment responses. Therefore, it should be considered as an alternative treatment approach in certain patient population including at risk population that may otherwise discharge from the hospital with no antimicrobial treatment or suboptimal oral antibiotics. Disclosures All Authors: No reported disclosures.

Epidemiology and Economic Outcomes Associated with Timely versus Delayed Receipt of Appropriate Antibiotic Therapy among US Patients Hospitalized for Native Septic Arthritis: A Retrospective Cohort Study.

Timely administration of appropriate antibiotic therapy is associated with better patient outcomes and lower costs of care compared to delayed appropriate therapy, yet initial treatment is often empiric since causal pathogens are typically unknown upon presentation. The challenge for clinicians is balancing selection of adequate coverage treatment regimens, adherence to antimicrobial stewardship principles to deter resistance, and financial constraints. This retrospective cohort study aimed to assess the magnitude and impact of delayed appropriate antibiotic therapy among patients hospitalized with septic arthritis (SA) in the U.S. from 2017 to 2019 using healthcare encounter data. Timely appropriate therapy was defined as the receipt of antibiotic(s) with in vitro activity against identified pathogens within two days of admission; all other patients were assumed to have received delayed appropriate therapy. Of the 517 patients admitted to hospital for SA who met all selection criteria, 26 (5.0%) received delayed appropriate therapy. In inverse-probability-treatment-weighting-adjusted analyses, the receipt of delayed appropriate therapy was associated with an additional 1.1 days of antibiotic therapy, 1.4 days in length of stay, and $3531 in hospital costs (all vs. timely appropriate therapy; all p ≤ 0.02). Timely appropriate therapy was associated with a twofold increased likelihood of antibiotic de-escalation during the SA admission.

223 Joint Aspirations for Suspected Native Septic Arthritis: A Retrospective Audit of the Diagnostic Accuracy of Aspirations and Clinical Factors Associated with a Diagnosis of Septic Arthritis

Abstract Aim This study aimed to determine the diagnostic accuracy of native joint aspirations for adult septic arthritis (SA), and to determine clinical factors associated with a positive diagnosis of SA. Method Retrospective review of adult patients (≥16yrs) undergoing a major joint aspiration at a single centre over a year period (2019) were identified. Patient demographics, clinical and biochemical data, joint aspiration details, post-aspiration diagnosis, management and patient outcomes were recorded. Culture negative SA was defined as Newman's Criteria C or D. Results There were 161 native joint aspirations identified. The rate of positive diagnosis of SA was 13.0%, (n=21), with 16 (9.9%) culture positive SA and five (3.1%) culture negative SA. The presence of organisms on gram stain, high synovial white cell count (WCC), history of fever, intravenous drug use (IVDU) and previous SA diagnosis were associated with a diagnosis of SA (all p&amp;lt;0.05). A history of crystal arthropathy made the diagnosis of SA less likely (p=0.025). C-reactive protein (CRP) was not statistically different in the SA and non-SA groups (Area Under Curve of ROC=0.63, p=0.55). Conclusion Joint aspiration is still the preferred diagnostic test when it comes to accurately diagnosing native joint SA. However, while synovial culture and gram stain are pending, a high index of suspicion for SA can be based on a combination of patient's presenting symptoms (history of fever), previous SA or IVDU, and a high synovial WCC. These factors can aid the decision as to whether an emergency surgical washout of the joint is indicated.

Arthroscopic Treatment Yields Lower Reoperation Rates than Open Treatment for Native Knee but Not Native Shoulder Septic Arthritis

PurposeTo compare the incidence, patient demographics, complication rates, readmission rates, and reoperation rates of open and arthroscopic surgery performed for septic arthritis in native knee and shoulder joints.MethodsRecords of patients who were diagnosed with native knee or shoulder septic arthritis and underwent open or arthroscopic irrigation and debridement (I&D) between 2015 and 2018 were queried from the PearlDiver Mariner Database. International Classification of Diseases 10th (ICD-10) diagnosis and procedure codes were used to identify patients and track reoperations. Reoperation procedures, including revision open and arthroscopic I&D, were analyzed at 1 month, 1 year, and 2 years. Complications, emergency department (ED) admissions, and hospital readmissions within 30 days were analyzed and compared between the open and arthroscopic cohorts.ResultsThe query resulted with 1,993 patients who underwent knee I&D (75.3% arthroscopic, 24.7% open, P < .001) and 476 patients who underwent shoulder I&D (64.8% arthroscopic, 35.2% open, P < .001). One-month complication rates (11.6-22.7%) and hospital readmission rates (15.8-19.6%) were similar for arthroscopic and open treatment for knee and shoulder septic arthritis. Reoperation rates for revision I&D of the knee were higher after open compared to arthroscopic treatment at 1 month, 1 and 2 years (20.9% vs. 16.7%, 32.5% vs 27.6% and 34.1% vs. 29.4%, P < .05, respectively). For shoulder septic arthritis 1-month, 1-year, and 2-year reoperation rates were similar for open and arthroscopic treatment (16.0% vs 11.7%, 22.0% vs 19.3%, and 22.7% vs 20.0%, P = .57, respectively). Lastly, 6.7% of patients with native septic knee arthritis underwent subsequent arthroplasty by 2 years.ConclusionArthroscopic treatment carries a lower reoperation rate than open surgery for knee septic arthritis, but in the shoulder, the risk for revision I&D is similar after arthroscopic or open surgery.

Native septic arthritis. Diagnostic and treatment principles

Evaldas Šivickas1, Karolina Staškevičiūtė1, Mantas Giedraitis2, Linas Zeniauskas2, Alfredas Smailys2, Justinas Stučinskas2 1 Lithuanian University of Health Sciences, Academy of Medicine, Kaunas, Lithuania 2 Department of Orthopaedics and traumatology, Medical Academy, Lithuanian University of Health Sciences, Kaunas, Lithuania Abstract Introduction: Native septic arthritis is a complex joint infection that requires urgent diagnosis and adequate treatment. […]

Prise en charge de l’infection sur articulation native : le point de vue du chirurgien

Native septic arthritis is a medical and surgical emergency, both diagnostic and therapeutic. Its management must be dynamic, multidisciplinary and adapted to joint damage stage because the preservation of function will depend on time to management and the good therapeutic which will have to be regularly reassessed. If iterative needle aspiration are possible in the first hours of fluid arthritis, they must quickly give way to arthroscopic lavage in unfavorable outcome. At synovial arthritis stage, a large synovectomy should be performed either by arthrotomy or arthroscopy, then at the final osteoarthritis stage, joint resection is required. Source of frequent sequelae, septic arthritis imposed in the short or medium term, joint reconstructions by prostheses in many patients. This procedure will require special care because of the significant residual infectious risk.

Efficacy and safety of arthroscopic treatment for native acute septic arthritis of the hip joint in adult patients

BackgroundAs septic arthritis is time-dependent and has a propensity for irreversible joint damage, early diagnosis and treatment are needed. Frequently, adult patients with septic arthritis cannot undergo invasive surgery because of comorbidities and a weakened immune system. Hip arthroscopic irrigation and debridement for native acute septic arthritis of the hip joint have been performed as the first choice of treatment for patients of all ages. This study aimed to assess the efficacy and safety of arthroscopic management for native acute septic arthritis of the hip joint in adult patients.MethodsFive adult patients (mean age, 46.2 years; all male) were retrospectively reviewed. Immediately after diagnosis, all patients underwent hip arthroscopic irrigation, debridement with synovectomy, and drainage. Partial weight-bearing was permitted once the C-reactive protein level normalised to < 1.0 mg/dl. Preoperative comorbidities, bacterial culture results, surgical complications, duration of hospital stay, time-to-confirmed normalisation of the C-reactive protein level, and recurrence incidence were evaluated.ResultsAll patients had comorbidities, and the cultured microorganisms differed among cases. There were no complications related to arthroscopic surgery. All patients achieved confirmed C-reactive protein normalisation within an average of 69.8 days, and there was no recurrence during the follow-up period (mean, 40.2 months; range, 16–60 months).ConclusionArthroscopic management for native acute septic arthritis of the hip joint is a safe and effective procedure in adult patients.

Clinical features and outcome of Streptococcus agalactiae bone and joint infections over a 6-year period in a French university hospital

Bone and joint infections (BJIs) due to Streptococcus agalactiae are rare but has been described to increase in the past few years. The objective of this study was to describe clinical features and outcomes of cases of S. BJIs. We conducted a retrospective analysis of adult cases of S. agalactiae BJIs that occurred between January 2009 and June 2015 in a French university hospital. The treatment success was assessed until 24 months after the end of antibiotic treatment. Among the 26 patients included, 20 (77%) were male, mean age was 62 years ± 13 and mean Charlson comorbidity index score was 4.9 ± 3.2. Diabetes mellitus was the most common comorbidity (n = 14, 54%). Six had PJI (Prosthetic Joint Infections), five osteosynthesis-associated infections, 11 osteomyelitis and four native septic arthritis. Eleven patients had a delayed or late infection: six with a prosthetic joint infection and five with an internal fixation device infection. Sixteen patients (62%) had a polymicrobial BJI, most commonly with Gram-positive cocci (75%) notably Staphylococcus aureus (44%). Polymicrobial infections were more frequently found in foot infections (90% vs 44%, p = 0.0184). During the two-year follow-up, three patients died (3/25, 12%) and seven (7/25, 28%) had treatment failure. Diabetes mellitus was the most common comorbidity. We observed an heterogenous management and a high rate of relapse.

Arthrotomic debridement of arthrotic septic arthritis of the knee is more effective than arthroscopic debridement and delays the need for prosthesis despite progression

Background and objective40%–50% of this septic arthritis occurs in the knee, despite rapid medical surgical treatment, 24%–50% will have a poor clinical outcome. It is not clear which debridement technique, by arthrotomy or arthroscopy, is more effective in controlling infection, or whether or not previous osteoarthritis worsens the outcome. The objective of this study on septic arthritis of the osteoarthritic knee was to analyse which surgical debridement technique, arthroscopy or arthrotomy, is more effective, the clinical and radiographic outcomes of the patients, and how many go on to require a TKR after the infection has healed. MethodsA retrospective study was performed in 27 patients with native septic arthritis of the knee. Eighteen were men and the mean age was 64.8 years (30–89 years). Fifteen patients were debrided by arthrotomy and 12 by arthroscopy. The effectiveness of debridement in controlling infection, the radiographic progression of the osteoarthritis on the Ahlbäch scale, the need for subsequent replacement, and pain and functional status were analysed using the VAS and WOMAC scales at 52.8 ± 11.2-month follow-up. ResultsThe infection was controlled in 93% and 92% of the patients, 13% and 42% required 2 or more surgeries for infection control, 18% and 44.4% showed progression of arthritis in the arthrotomy and arthroscopy groups, respectively. One patient in each group required a knee replacement. The VAS score was superior in the arthrotomy group and there were no differences in WOMAC score. ConclusionDebridement by arthrotomy in the emergency department by non-sub-specialist knee surgeons is more effective than arthroscopic debridement in controlling septic arthritis of the knee. Surgical debridement of septic arthritis in knees with previous osteoarthritis enabled control of the infection with no pain despite the progression of the osteoarthritis.

Risk Factors, Screening, and Treatment Challenges in Staphylococcus aureus Native Septic Arthritis.

Background Staphylococcus aureus is the most common cause of native septic arthritis. Few studies have characterized this disease during the US opioid epidemic. The role of methicillin-resistant Staphylococcus aureus (MRSA) nasal screening in this disease has not been elucidated. We sought to identify risk factors and outcomes for S. aureus native septic arthritis and to evaluate MRSA screening in this disease.MethodsA retrospective cohort study of native septic arthritis patients (2012–2016) was performed. Demographics, risk factors, and outcomes were compared between Staphylococcus aureus and other native septic arthritis infections. Sensitivity, specificity, and predictive values of MRSA screening were assessed.ResultsTwo hundred fifteen cases of native septic arthritis were included. S. aureus was cultured in 64% (138/215). MRSA was cultured in 23% (50/215). S. aureus was associated with injection drug use (odds ratio [OR], 4.33; 95% CI, 1.74–10.81; P = .002) and switching antibiotics (OR, 3.92; 95% CI, 1.01–21.38; P = .032). For every 10-year increase in age, the odds of S. aureus decreased (OR, 0.72; 95% CI, 0.60–0.87; P = .001). For 1-unit increases in Charlson comorbidity index score, the odds of S. aureus decreased (OR, 0.82; 95% CI, 0.73–0.91; P = .0004). MRSA screening during admission demonstrated a sensitivity of 0.59, specificity of 0.96, positive predictive value of 0.85, and negative predictive value of 0.84 for MRSA native septic arthritis.ConclusionsThe opioid epidemic may be contributing to a demographic shift in native septic arthritis to younger, healthier individuals. S. aureus native septic arthritis has unique risks, including injection drug use. MRSA screening may be useful to rule in MRSA native septic arthritis.

Primarily treated patients versus referred patients in the treatment of native septic arthritis of digits: a retrospective comparative study

BackgroundSeptic arthritis of digits needs urgent treatment. When treatments delayed or insufficient, patients may be referred to the upper-level hospital due to uncontrolled infection. We reviewed the treatment history of referred patients and compared the microorganisms and the clinical course of both primary and referred patients as relevant studies are rare.MethodsIn this retrospective review of consecutive case series, 45 patients (primary, n = 11; referred, n = 34) were treated with multiple irrigation and debridement. Cefazolin was used as empiric antibiotics, then changed according to microbiologic study. Previously used antibiotics, treatment delay, surgical history of the referred patients were reviewed. Identified microorganisms, required surgical intervention, hospital stay, radiologic outcome, functional outcomes were compared between both groups.ResultsIn the referred patients, methicillin-resistant Staphylococcus aureus (MRSA) was commonly found and cefazolin was susceptible in only 15% of the cases. Longer hospital stay, prolonged antibiotic therapy, more surgical intervention including flap surgery was required to treat the referred patients. Postoperative pain was not severe in daily activities, but the final range of motion was significantly less in the referred patients compared to the primary patients.ConclusionsThis study suggests that in the treatment of uncontrolled septic arthritis of the digits, antibiotic agents covering MRSA may shorten the duration of antibiotic therapy in areas of high MRSA incidence. Besides, more number of I & D including flap surgery may be required for the referred patients compared with the primary patients. These findings can help the surgeon in setting up a treatment plan or in counseling of referred patients with uncontrolled septic arthritis of the digits.

Risk Factors for Failure and Optimal Treatment of Total Joint Arthroplasty for Septic Arthritis

BackgroundPatients with native joint septic arthritis are one of the highest risk groups for developing complications following total joint arthroplasty (TJA), especially periprosthetic joint infection(PJI). There is a paucity of information on the risk factors for developing PJI and the optimal treatment modality of the native septic joint that can mitigate that risk. This multicenter study aimed to determine these risk factors, including prior treatment. MethodsA retrospective study of 233 TJAs performed, following prior septic arthritis at five institutions, was conducted. Comorbidities, organism profile, prior surgery, etiology of septic arthritis, and other relevant variables were reviewed. The primary outcome was the development of PJI, defined by Musculoskeletal Infection Society criteria. Bivariate and multivariate analyses were performed to identify risk factors for PJI. ResultsOverall, the PJI rate was 12.4% in patients who underwent TJA after native septic arthritis. Predisposing risk factors for PJI included antibiotic-resistant organisms, male gender, diabetes, and a postsurgical cause of septic arthritis eg open reduction internal fixation. When controlling for potential confounders, multivariate analysis revealed that male gender, diabetes, and a postoperative etiology were predictors of PJI. The definitive treatment modality for the septic joint did not affect the rate of PJI for both arthroscopy vs irrigation and debridement (I&D), and two-stage exchange vs single-stage procedure. DiscussionThis study has identified several risk factors for developing PJI in patients with prior septic joint arthritis, some of which are modifiable. The initial treatment modality of the native septic joint has no bearing on the development of PJI after TJA.

El desbridamiento por artrotomía de la artritis séptica de rodilla artrósica es más eficaz que el artroscópico y retrasa la necesidad de prótesis a pesar de la progresión de la artrosis

Background and objective40%-50% of this septic arthritis occurs in the knee, despite rapid medical surgical treatment, 24%-50% will have a poor clinical outcome. It is not clear which debridement technique, by arthrotomy or arthroscopy, is more effective in controlling infection, or whether or not previous osteoarthritis worsens the outcome. The objective of this study on septic arthritis of the osteoarthritic knee was to analyse which surgical debridement technique, arthroscopy or arthrotomy, is more effective, the clinical and radiographic outcomes of the patients, and how many go on to require a TKR after the infection has healed. Material and methodsA retrospective study was performed in 27 patients with native septic arthritis of the knee. Eighteen were men and the mean age was 64.8 years (30-89years). Fifteen patients were debrided by arthrotomy and 12 by arthroscopy. The effectiveness of debridement in controlling infection, the radiographic progression of the osteoarthritis on the Ahlbäch scale, the need for subsequent replacement, and pain and functional status were analysed using the VAS and WOMAC scales at 52.8±11.2-month follow-up. ResultsThe infection was controlled in 93% and 92% of the patients, 13% and 42% required 2 or more surgeries for infection control, 18% and 44.4% showed progression of arthritis in the arthrotomy and arthroscopy groups, respectively. One patient in each group required a knee replacement. The VAS score was superior in the arthrotomy group and there were no differences in WOMAC score. ConclusionDebridement by arthrotomy in the emergency department by non-sub-specialist knee surgeons is more effective than arthroscopic debridement in controlling septic arthritis of the knee. Surgical debridement of septic arthritis in knees with previous osteoarthritis enabled control of the infection with no pain despite the progression of the osteoarthritis.

Two-Stage Primary Arthroplasty of Native Hips and Knees That Had Previously Failed Treatment for Septic Arthritis: A Single-Center Experience.

BackgroundPatients with a history of degenerative joint disease secondary to an acute or remote episode of septic arthritis of the native knee or hip present a unique challenge for the orthopaedic surgeon. This study describes our experience with two-stage primary arthroplasty for such patients.MethodsWe reviewed 42 patients with a history of septic arthritis treated with two-stage primary arthroplasty between 2008 and 2018. Patients were evaluated using modified Harris Hip Score, Knee Society Score (KSS), and KSS functional component (KSSF). Paired t-tests were used to compare changes for continuous variables within cohorts. Multivariate linear and logistic regression models were constructed to determine predictors of outcomes and complications.ResultsAt a mean of 3.3-year follow-up, there were 14 (33.3%) complications and the infection cure rate was 95.2%. On average, patients improved in the modified Harris Hip Score (42.9 ± 11.8 vs 83.3 ± 11.1, P < .001), KSS (35.9 ± 16.9 vs 80.1 ± 16.6, P < .001), KSSF (38.0 ± 15.1 vs 71.5 ± 24.0, P < .001), knee flexion (90.9 ± 14.9 vs 100.5 ± 17.1), and hip flexion (73.8 ± 21.2 vs 102.1 ± 11.8, P < .001). Age (β: −0.78, P = .004) was independently associated with lower Harris Hip Score in the hip cohort. There were no independent predictors of the KSS or KSSF. The erythrocyte sedimentation rate (odds ratio: 1.07, P = .043) and C-reactive protein (odds ratio: 1.43, P = .018) at stage 2 were independently associated with a higher likelihood of complications at the final follow-up.ConclusionPatients with a history of native septic arthritis of the hip and knee, and secondary end-stage degenerative joint disease, showed significant postoperative improvements and a high rate of complications after two-stage primary total joint arthroplasty. Despite improvements, some patients may necessitate a third operation because of the incidence of reinfection and spacer exchange. This information should be used to counsel patients who present with this challenging clinical scenario.

A Retrospective Review of Native Septic Arthritis in Patients: Can We Diagnose Based on Laboratory Values?

IntroductionThe accurate diagnosis of acute septic arthritis is essential to initiating appropriate treatment and minimizing potential cartilage damage. A synovial fluid cell count of 50,000 cells/mm3 has been used as a diagnostic cutoff for acute septic arthritis, although data supporting this is lacking. The purpose of this study was to assess the efficacy of synovial cell counts to predict septic arthritis in patients with symptomatic native joints.MethodsA retrospective review was performed of patients who were evaluated for septic arthritis at a single institution with the use of synovial fluid analysis and adjunctive lab tests. Exclusion criteria included history of a total joint arthroplasty of the affected joint or immunocompromised state. A true infection was considered on the basis of positive or negative synovial aspirate cultures. We evaluated the synovial cell count, synovial polymorphonuclear cell percentile (% neutrophils), serum white blood cell (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in order to determine their association and predictive power in a true infection.ResultsOf the 65 patients included in the study, 40 (61.5%) had a positive culture for septic arthritis and 25 (38.5%) had negative cultures. Patients with positive cultures had a larger median % neutrophils than patients with negative cultures (median: 93 vs. median: 86, P=0.041). They also tended to have higher serum CRP levels compared to negative culture patients (median: 142.30 vs. 34.20, P=0.051). No outcomes were independently highly effective in discriminating between patient groups (area under the curve (AUC) ≤ 0.67). There was no significant difference between the synovial cell counts in patients with culture positive septic arthritis and patients with negative cultures (median: 32435 vs 35385, P = 0.94). ConclusionPatients with culture proven septic arthritis had larger % neutrophils. However, there were no other statistically significant differences between patient groups regarding ESR, CRP, WBC, or cell count aspiration at the time of diagnosis. No synovial cell count level was highly effective in discriminating patients with a positive culture for septic arthritis from patients with negative cultures.