Role of bariatric surgery in reducing periprosthetic joint infections in total knee arthroplasty. A systematic review and meta-analysis.

BACKGROUND: Obesity represents an epidemic of rising numbers worldwide year after year. In the Orthopedic field, obesity is one of the major causes leading to osteoarthritis needing Total Joint Arthroplasty (TJA). Still, contextually, it represents one of the most significant risk factors for joint replacement complications and failures. So, bariatric Surgery (BS) is becoming a valuable option for weight control and mitigating obesity-related risk factors. This review of the literature and meta-analysis aims to evaluate periprosthetic joint infections (PJI) and surgical site infections (SSI) rates in patients who underwent TKA after BS compared to obese patients without BS. METHODS: Systematic review was performed according to Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines up to October 2023. We included longitudinal studies comparing obese patients who underwent total knee arthroplasty after bariatric surgery (study group) and obese patients who underwent TKA (control group). The surgical site infection and Periprosthetic joint infection rate were compared among groups using a meta-analytical approach. RESULTS: The online database and references investigation identified one hundred and twenty-five studies. PJI rate differed significantly among groups, (z = -21.8928, p < 0.0001), with a lower risk in the BS group (z = -10.3114, p < 0.0001), for SSI, instead, not statistically significance were recorded (z = -0.6784, p = 0.4975). CONCLUSIONS: The current Literature suggests that Bariatric Surgery can reduce infectious complications in TKA, leading to better outcomes and less related costs treating of knee osteoarthritis in obese patients.

Effect of Antibiotic Prophylaxis on Infection Rates in Pediatric Supracondylar Humerus Fractures Treated with Closed Reduction and Percutaneous Pinning: A Prospective Double-Blinded Randomized Controlled Trial.

BACKGROUND: Supracondylar humerus fractures (SCHFs) are the most common elbow fracture in the pediatric population. In the case of displaced fractures, closed reduction and percutaneous Kirschner wire pinning (CRPP) is commonly performed. Infection rates are between 0 and 7%; however, retrospective studies have shown no benefit of preoperative antibiotics. There continues to be notable variability in antibiotic usage based on surgeon preference and local institutional policy. We conducted a double-blinded, randomized controlled trial to evaluate whether antibiotic prophylaxis reduces the risk of infection in pediatric SCHF patients treated with CRPP. METHODS: Pediatric patients with displaced SCHF who presented to a pediatric hospital were enrolled and randomized into two groups. Group I received one dose of prophylactic antibiotics (25 mg/kg cefazolin IV up to 1g or clindamycin 10 mg/kg up to 600 mg/kg IV in the case of cefazolin allergy). Group II received placebo (10-mL prefilled syringe of normal saline). All patients underwent CRPP and casting followed by pin removal 3 to 6 weeks after the initial procedure. The presence of pin-site infection, erythema, drainage, septic arthritis, and osteomyelitis was recorded. RESULTS: One hundred sixty patients were enrolled in the study. Eighty-two patients were randomized to receive antibiotics, and 78 patients were randomized to placebo. No difference was seen in the rate of infection between the treatment groups (1.2% in the antibiotic group versus 1.3% in the placebo group; P = 1.00). Presence of purulent drainage (0.0% versus 1.3%; P = 0.49), septic arthritis (0.0% versus 0.0%; P = 1.00), and osteomyelitis (1.2% versus 0.0%; P = 1.00) was similar in both groups. No difference in the need for additional antibiotics (1.2% versus 1.3%; P = 1.00) or additional surgery (1.2% versus 0.0%; P = 1.00) was found between groups. DISCUSSION: The use of antibiotic prophylaxis did not affect the risk of infection in pediatric patients who underwent CRPP for displaced SCHF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT03261830. LEVEL OF EVIDENCE: Therapeutic Level I.

Editorial Commentary: Arthroscopic Irrigation and Debridement is an Effective Treatment for Acute Septic Arthritis of Native Joints.

Arthroscopic irrigation and debridement has long been known to be an effective treatment for acute septic arthritis of native joints. Systematic review shows that when compared to open irrigation and debridement, arthroscopy yields comparable hospital length of stay complication, reoperation, and readmission rates, as well as better patient-reported outcomes compared to open arthrotomy. However, reoperation rates are heterogeneously defined in the literature, not to mention that unplanned return to surgery likely suggests inadequate prior irrigation and debridement of an infection, whereas a planned repeat washout may be a surgeon's intention and practice for septic arthritis. Most of all, this condition should be managed urgently.

Is Prophylactic Antibiotic Use Necessary Before Dental Procedures in Primary and Revision TKA? A Propensity Score-matched, Large-database Study.

BACKGROUND: The question of whether dental procedures increase the risk of periprosthetic joint infection (PJI) in patients who have undergone total joint arthroplasty (TJA) remains controversial. QUESTIONS/PURPOSES: (1) Are dental procedures associated with an increased incidence of PJI in the setting of either primary or revision TKA after controlling for relevant potentially confounding variables? (2) Is the administration of prophylactic antibiotics before dental procedures associated with any differences in this risk? (3) Which factors are associated with increased incidence of PJI after dental procedures? METHODS: This nationwide, retrospective, comparative, large-database study evaluated 591,602 patients who underwent unilateral primary or revision TKA between 2009 and 2019 using the Health Insurance Review and Assessment Service data in South Korea, in which all people in South Korea were registered and to which all medical institutions must charge any procedures they performed. The study population was divided into 530,156 patients with dental procedures and 61,446 patients without dental procedures based on whether the patients underwent a dental procedure at least 1 year after the index surgery. After propensity score matching, patients were classified into a dental (n = 182,052) and a nondental cohort (n = 61,422). The dental cohort was then divided into two groups: 66,303 patients with prophylactic antibiotics and 115,749 patients without prophylactic antibiotics based on prophylactic antibiotic use. After propensity score matching, patients were categorized into prophylactic (n = 66,277) and nonprophylactic (n = 66,277) cohorts. Propensity score matching was used to control for covariates including posttraumatic arthritis associated with PJI risk according to the dental procedure and prophylactic antibiotic use among the cohorts. After propensity score matching, the standardized mean difference was confirmed to be less than 0.1 for all variables. Kaplan-Meier survival analyses, log-rank tests, and Cox proportional hazards regression analysis was performed. RESULTS: Dental procedures were not associated with an increase in PJI risk after primary (adjusted HR 1.56 [95% CI 0.30 to 8.15]; p = 0.60) or revision TKA (adjusted HR 1.74 [95% CI 0.90 to 3.34]; p = 0.10). Additionally, use of prophylactic antibiotics was not associated with a reduced PJI risk after the index surgery, either for primary (adjusted HR 1.28 [95% CI 0.30 to 5.42]; p = 0.74) or revision TKA (adjusted HR 0.74 [95% CI 0.45 to 1.23]; p = 0.25). Although surgery type and prophylactic antibiotic use exhibited no influence on PJI occurrence after dental procedures, posttraumatic arthritis was associated with PJI. The adjusted HR for posttraumatic arthritis was 4.54 (p = 0.046). CONCLUSION: Our findings suggest that dental procedures were not associated with an increased risk of PJI for up to 2 years after the dental procedure in patients who underwent either primary or revision TKA. Based on these findings, there is insufficient rationale for the use of prophylactic antibiotics before dental procedures in patients who have undergone primary or revision TKA. LEVEL OF EVIDENCE: Level III, therapeutic study.

The effect of preoperative different dexamethasone regimens on postoperative glycemic control in patients with type 2 diabetes mellitus undergoing total joint arthroplasty: a retrospective cohort study.

BACKGROUND: Concerns have been raised regarding the impact of preoperative intravenous dexamethasone on postoperative glycemic control in diabetic patients undergoing total joint arthroplasty (TJA). This study aimed to determine relationships between preoperative different dexamethasone regimens and postoperative fasting blood glucose (FBG), as well as to identify risk factors for postoperative FBG ≥ 200 mg/dl in diabetic patients undergoing TJA. METHODS: This retrospective study included 1216 diabetic patients undergoing TJA and categorized into group A (dexamethasone = 0 mg), group B (dexamethasone = 5 mg), and group C (dexamethasone = 10 mg). All dexamethasone was administered before skin incision. FBG levels were monitored until postoperative day (POD) 3. Analyses were conducted for periprosthetic joint infection (PJI) and wound complications during 90 days postoperatively. And the risk factors for postoperative FBG ≥ 200 mg/dl were identified. RESULTS: Preoperative dexamethasone administration resulted in a transiently higher FBG on POD 0 and POD 1 (all P < 0.001). However, no differences were observed on POD 2 (P = 0.583) and POD 3 (P = 0.131) among three groups. While preoperative dexamethasone led to an increase in postoperative mean FBG and postoperative maximum FBG (all P < 0.001), no differences were found in wound complications (P = 0.548) and PJI (P = 1.000). Increased HbA1c and preoperative high FBG, but not preoperative dexamethasone, were identified as risk factors for postoperative FBG ≥ 200 mg/dl. Preoperative HbA1c level of ≥ 7.15% was associated with an elevated risk of postoperative FBG ≥ 200 mg/dl. CONCLUSIONS: Although preoperative intravenous administration of 5 mg or 10 mg dexamethasone in diabetic patients showed transient effects on postoperative FBG after TJA, no differences were found in the rates of PJI and wound complications during 90 days postoperatively. Notably, patients with a preoperative HbA1c level of ≥ 7.15% and elevated preoperative FBG may encountered postoperative FBG ≥ 200 mg/dl.

Civilian Ballistic Arthrotomies: Infection Rates and Operative Versus Nonoperative Management.

OBJECTIVES: The purpose of this study was to determine whether a significant difference existed in the rate of infection after ballistic traumatic arthrotomy managed operatively compared with those managed without surgery. DESIGN: Retrospective cohort study. SETTING: Academic Level I Trauma Center. PATIENT SELECTION CRITERIA: Patients with ballistic traumatic arthrotomies of the shoulder, elbow, wrist, hip, knee, or ankle who received operative or nonoperative management. OUTCOME MEASURES AND COMPARISONS: The rates of infection and septic arthritis in those who received operative or nonoperative management. RESULTS: One hundred ninety-five patients were studied. Eighty patients were treated nonoperatively (Non-Op group), 16 patients were treated with formal irrigation and debridement in the operating room (I&D group), and 99 patients were treated with formal I&D and open reduction and internal fixation (ORIF) (I&D + ORIF group). Patients in all 3 groups received local wound care and systemic antibiotics. No patients in the Non-Op or I&D group developed an infection. Six patients in the I&D + ORIF group developed extra-articular postoperative infections requiring additional interventions. CONCLUSIONS: The infection rate in the I&D + ORIF group was consistent with the infection rates reported in orthopaedic literature after fixation alone. In addition, none of the infections were cases of septic arthritis. This suggests that traumatic arthrotomy does not increase the risk for infection beyond what is expected after fixation alone. Importantly, the Non-Op group represented a series of 80 patients who were treated nonoperatively without developing an infection, indicating that I&D may not be necessary to prevent infection after ballistic arthrotomy. The results suggest that septic arthritis after civilian ballistic arthrotomy is a rare complication regardless of the choice of treatment. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Extraarticular infection 9 years after anterior cruciate ligament reconstruction. Case report.

Extraarticular infection after anterior cruciate ligament reconstruction (ACLr) is a rare condition with challenging diagnosis because the symptoms are milder and more insidious when compared to septic arthritis. When late (>2 months after surgery), it tends to be associated with osteomyelitis, requiring more extensive surgical debridement and hardware removal. We report a case of extraarticular infection after ACLr, in the acute phase affecting the tibial site and 9 years after index surgery affecting around the femur site. There was no progression to osteomyelitis at any of the sites. The infection developed a large posterolateral encapsulated abscess, with the endobutton plate loose inside it with its loop intact. In addition to the absence of osteomyelitis progression, there was no sinus tract formation, graft or joint involvement. With open debridement and antibiotic therapy, the patient returned to his activities without limitations. The reported case highlights that extraarticular infection after ACLr, while rare, can be challenging to diagnose and treat. However, with appropriate treatment, it can lead to good results with no functional limitations.

Inferior Outcomes for Patients Transferred Between Surgical Stages for Knee Periprosthetic Joint Infection.

BACKGROUND: Periprosthetic joint infection (PJI) in total knee arthroplasty may result in 2-stage revision surgery. There are limited data describing outcomes when the first stage is completed at an outside hospital and the patient is referred to a tertiary center. We hypothesized that patients have greater success when both surgeries occur at a single center. METHODS: There were 25 knee PJI patients who presented with an antibiotic spacer and had a minimum 2-year follow-up who were retrospectively identified at a single tertiary referral center from 2014 to 2021. A cohort matched for age, sex, body mass index, Elixhauser comorbidity measure, spacer type, infectious organism, and year of surgery was established with patients who had both stages completed at the investigating institution. Modified Delphi success criteria of no subsequent surgery or reinfection with any species were compared. RESULTS: The transferred group demonstrated a treatment success of 40% compared to 84% in the continuous group (P < .01). The transferred group was more likely to have an additional procedure between stages (44 versus 8%, P < .01), with a higher number of surgeries after primary total knee arthroplasty (4.8 versus 3.0, P < .01), between stages (1.4 versus 0.2, P < .01), and after second stage (0.8 versus 0.2, P = .03). The transferred group had longer durations between stages (20.1 versus 7.0 weeks, P < .01). CONCLUSION: Patients who have PJIs transferred between stages demonstrated higher treatment failure. Surgeons should consider transfer early with a goal of continuous management by a single institution.

Clinical characteristics and long-term outcomes of septic arthritis of the native hip joint: a 20-year retrospective review.

BACKGROUND: The primary purpose of this retrospective case series was to describe the prevalence and outcomes of single-stage hip arthroplasty in patients who were previously treated for septic arthritis of the native hip at our institution over a 20-year period. This study also examined rates of persistent or recurrent infection, reoperation, and mortality for septic arthritis of the native hip. METHODS: Adult patients treated for septic arthritis of the native hip at our institution from 1995 to 2015 were retrospectively identified. Exclusion criteria included age <18 years, missing or incomplete medical records, treatment at an outside institution, and prior surgery of the hip. RESULTS: 97 patients were included in this study. 3 patients (3.1%) who were previously treated for septic arthritis of the native hip underwent single-stage hip arthroplasty an average of 40 ± 25 months from the date of infection. 3 of the 18 (16.7%) patients who were treated with resection arthroplasty underwent second-stage joint reconstruction. There were no cases of periprosthetic joint infection (PJI). 1 patient who underwent single-stage arthroplasty experienced implant-induced metallosis, necessitating removal of the implant. There were no other cases of revision arthroplasty. CONCLUSIONS: The prevalence of single-stage hip arthroplasty in patients with a history of septic arthritis of the native hip joint was 3.1%, which is higher than the prevalence of hip arthroplasty in the United States general population, suggesting that a history of septic arthritis may increase the risk of requiring hip arthroplasty. In the small number of patients who went on to receive a hip replacement, there were no reported cases of PJI. This study suggests that hip arthroplasty is a viable option for patients with symptomatic osteoarthritis and a history of septic arthritis of their hip.

Demographics and Early Outcomes of Commercial Antibiotic Cement Usage for Infection Prophylaxis During Primary Total Knee Arthroplasty in Patients Older Than 65 Years: An American Joint Replacement Registry Study.

INTRODUCTION: The use of antibiotic-laden bone cement (ALBC) for infection prophylaxis in the setting of primary total knee arthroplasty (TKA) remains controversial. Using data from the American Joint Replacement Registry (AJRR), (1) we examined the demographics of ALBC usage in the United States and (2) identified the effect of prophylactic commercially available ALBC on early revision and readmission for prosthetic joint infection (PJI) after primary TKA. METHODS: This is a retrospective cohort study of the AJRR from 2017 to 2020. Patients older than 65 years undergoing primary cemented TKA with or without the use of commercially available antibiotic cement were eligible for inclusion (N = 251,506 patients). Data were linked to available Medicare claims to maximize revision outcomes. Demographics including age, sex, race/ethnicity, Charlson Comorbidity Index (CCI), preoperative inflammatory arthritis, region, and body mass index (BMI) class were recorded. Cox proportional hazards regression analysis was used to evaluate the association between the two outcome measures and ALBC usage. RESULTS: Patients undergoing cemented TKA with ALBC were more likely to be Non-Hispanic Black ( P < 0.001), have a CCI of 2 or 3 ( P < 0.001), reside in the South ( P < 0.001), and had a higher mean BMI ( P < 0.001). In the regression models, ALBC usage was associated with increased risk of 90-day revision for PJI (hazards ratio 2.175 [95% confidence interval] 1.698 to 2.787) ( P < 0.001) and was not associated with 90-day all-cause readmissions. Male sex, higher CCI, and BMI >35 were all independently associated with 90-day revision for PJI. DISCUSSION: The use of commercial ALBC in patients older than 65 years for primary TKA in the AJRR was not closely associated with underlying comorbidities suggesting that hospital-level and surgeon-level factors influence its use. In addition, ALBC use did not decrease the risk of 90-day revision for PJI and was not associated with 90-day readmission rates.

Floating Knee Arthrodesis After Prosthetic Knee Infection: A Report of 48 Cases.

BACKGROUND: Knee arthrodesis is a means of avoiding above-knee amputation after a prosthetic joint infection (PJI). The objective of this study was to analyze the results of floating knee arthrodesis in patients who had a history of aprosthetic knee infection. The analysis consisted of determining reinfection rates, functional results, and the survival of arthrodesis. METHODS: There were 48 patients who underwent a cemented floating knee arthrodesis in cases of PJI retrospectively included in the study, having been operated on between 2012 and 2020. In addition to being evaluated clinically, analytically, and radiographically, the patients were assessed functionally by means of a newly-created scale. RESULTS: At a mean follow-up of 4 years (1 year to 9 years), 7 patients suffered reinfection (14.6%). The recurrence of infection was not observed to be significantly affected by sex (P = .16), age(P = .09), or the type of surgery previously undergone (P = .18), nor was the McPherson Host Grade (P = .4) observed to have a significant effect. Patients who had a McPherson Limb Grade 3 were more likely to suffer reinfection than those with a McPherson Limb Grade 2 (P = .034). There were 26 patients (54%)fully evaluated and scored on the Knee Arthrodesis Functional Scale(BAOR). For 11 patients (42%), the results were evaluated as excellent, for 11 (42%) acceptable, for 3 (12%) low, and for 1(4%) poor. CONCLUSION: The arthrodesis nail is an effective and safe procedure for patients who have a recurrent PJI, providing an effective alternative when the criteria for a new revision total knee arthroplasty are not met.

High Incidence of Acute Kidney Injury Following Antibiotic-Loaded Spacer Insertion for Periprosthetic Joint Infection: An Updated Review of the Literature.

BACKGROUND: The use of antibiotic-impregnated cement during 2-stage revision arthroplasty for periprosthetic joint infection poses a risk of renal complications following spacer insertion. This systematic review aimed to investigate the rate of acute kidney injury (AKI) following antibiotic-loaded spacer insertion and to identify risk factors associated with this complication. METHODS: A systematic review was performed using PubMed, Cochrane Central, and Scopus databases. All clinical studies that documented renal complications following antibiotic-loaded spacer insertion for periprosthetic knee (total knee arthroplasty [TKA]) or hip (total hip arthroplasty [THA]) infection were included. Articles that combined THA and TKA outcomes were also included and labeled "THA + TKA." Descriptive statistics were analyzed when data were available. RESULTS: There were 24 studies (9 THA, 7 TKA, 8 THA + TKA) included. The mean incidences of spacer-related AKI across THA, TKA, and THA + TKA cohorts were 4.2 (range, 0 to 10%), 14 (range, 0 to 19%), and 27% (range, 0 to 35%), respectively. The most common patient-related risk factors for AKI were underlying chronic kidney disease or high baseline creatinine, low preoperative hemoglobin, and blood transfusion requirement. Spacer-related risk factors included high antibiotic dosage (>3.6 g/cement batch) and antibiotic type. While most recovered without complication, select patients required hemodialysis for acute management (2 THA, 18 THA + TKA) and/or developed chronic kidney disease (8 TKA, 8 THA). CONCLUSION: The rate of AKI following spacer insertion was high and likely under-reported in the literature. Surgeons should be cognizant of this devastating complication and should closely monitor at-risk patients for AKI following antibiotic-loaded spacer insertion.

A pilot study of mitochondrial response to an in vivo prosthetic joint Staphylococcus aureus infection model.

Prosthetic joint infections (PJI) are associated with orthopaedic morbidity and mortality. Mitochondria, the "cell's powerhouses," are thought to play crucial roles in infection response and in increased risk of sepsis mortality. No current research discusses PJI's effect on mitochondrial function and a lack of understanding of immune-infection interactions potentially hinders patient care. The purpose of this pilot study was to evaluate the impact of simulated PJI on local tissue mitochondrial function. Using an established prosthetic implant-associated in vivo model, tissues were harvested from the surgical limb of a methicillin-sensitive Staphylococcus aureus implant-associated infection group (n = 6) and compared to a noninfected group (n = 6) at postoperative day (POD) 21. Using mitochondrial coupling assays, oxygen consumption rate and extracellular acidification rate were assessed in each group. Electron flow through mitochondrial complexes reflected group activity. Electron Paramagnetic Resonance (EPR) spectrometry measured the oxidizing potential of serum samples from infected versus noninfected groups. On POD21, colony-forming units per gram of tissue showed 5 × 109 in the infected group and 101 in the noninfected group (p < 0.0001). Maximal respiration and oxygen consumption due to adenosine triphosphate synthesis were significantly lower in isolated mitochondria from infected limbs (p = 0.04). Both groups had similar complex I, III, IV, and V activity (p > 0.1). Infected group EPR signal intensity reflecting reactive oxygen species levels was 1.31 ± 0.30 compared to 1.16 ± 0.28 (p = 0.73) in the noninfected group. This study highlights PJI's role in mammalian cell mitochondrial dysfunction and oxidative tissue damage, which can help develop interventions to combat PJI.

Adjuvant intra-articular vancomycin for recalcitrant Staphylococcal prosthetic joint infections of the knee.

OBJECTIVE: Chronic prosthetic joint infection patients who fail conventional two-stage revision surgery are an especially difficult to treat patient population. Consequently, the objective of this study was to investigate the safety and long-term effectiveness of adjuvant intra-articular vancomycin therapy in conjunction with two-stage revision knee arthroplasties for recalcitrant Staphylococcal prosthetic joint infections. METHODS: This was an observational cohort study of twelve patients with recalcitrant Staphylococcal prosthetic joint infections of the knee which had failed previous revision surgeries. Each patient subsequently underwent two-stage revision with placement of Hickman catheters to deliver intra-articular vancomycin therapy. In addition, systemic antibiotic therapy was administered for 6 weeks, and long-term follow-up was evaluated then for 5 years. RESULTS: Seventy-five percent of the cohort have had no recurrence of their infections at 5 years. Two patients formed fistulas requiring above the knee amputations, and three patients had acute kidney injury. All patients had maximum measurable serum vancomycin trough levels that ranged from 6.1 to 93.6 mcg/mL. CONCLUSION: The aggressive protocol used in this cohort with repeat two-stage revision surgery, intra-articular vancomycin and systemic antibiotics was able to prevent recurrence of infection in most patients, but higher than expected rates of acute kidney injury were observed in this study. Therefore, while intra-articular vancomycin therapy may have some effectiveness in treating recalcitrant prosthetic joint infections, its ability to eradicate all bacterial niduses is unproven, and clinicians should be cognizant of potential adverse events that can occur with this therapy.

Staged Approach to Tibial Nail Removal Poses Increased Risk for Infection in the Setting of Total Knee Arthroplasty.

BACKGROUND: While previous research has addressed conversion arthroplasty scenarios, there is limited data on outcomes of staged or concurrent removal of intramedullary (IM) nails during total knee arthroplasty (TKA). Our study aimed to explore the association between the timing of IM nail removal and the incidence of periprosthetic joint infection (PJI), surgical site infection (SSI), manipulation under anesthesia (MUA), and aseptic revision at 90 days, 1 year, and 2 years after TKA when IM nail removal is performed in either a (1) staged or (2) concurrent manner. METHODS: We queried a national, all-payer database of all patients who underwent a primary TKA and hardware removal of an IM tibial nail. The group was separated into mutually exclusive cohorts with removal performed either (1) in a staged manner (n = 287) or (2) on the same day of TKA (n = 2,958). Surgical complications included the following: PJIs, SSIs, MUAs, and aseptic revisions. Surgical complications were collected at 90-day, 1 year, and 2-year time points. RESULTS: Patients who had staged nail removal before TKA demonstrated the highest incidence of PJI at 90 days, 1 year, and 2 years (13.9, 16.7, and 17.1%, respectively). Adjusted multivariate regression analyses demonstrated significantly higher odds of a PJI, SSI, and MUA at 90 days, 1 year, and 2 years for all patients who had staged nail removal TKA (P < .001). CONCLUSIONS: There was an observed association between concurrent IM nail removal and a decreased risk of PJI, SSI, and MUA when compared to patients who had nail removal in a staged fashion. However, this does not discount the utility of the staged approach, as it may be necessary for patients less tolerant to longer operative times.

Dual Surgical Setup Associated with Reduced Infection Recurrence for Hip and Knee Arthroplasty After Two-Stage Exchange.

INTRODUCTION: Two-stage exchange (TSE) is the gold standard for the treatment of chronic periprosthetic joint infection (PJI) after total joint arthroplasty of the hip and knee in the United States. Failure of treatment can have devastating consequences for the patient, including poor functional outcomes, multiple further surgeries, and increased mortality. Several factors associated with infection recurrence have previously been identified in the literature. The purpose of this study was to evaluate whether the use of a dual surgical setup was associated with reduced risk of recurrence after TSE for PJI. METHODS: A retrospective study was conducted between January 2000 and December 2021 to isolate patients who underwent TSE after total joint arthroplasty of the hip and knee. Failure was defined as infection recurrence requiring surgical intervention. Demographic factors (age, sex, body mass index, smoking status, American Society of Anesthesiologists status), preoperative comorbidities (hypertension, cardiac disease, diabetes status, depression diagnosis, pulmonary disease), operating surgeon, single versus dual setup, hospital setting, use of long-term antibiotics postoperatively after TSE, aspiration data, and infecting organism were compared between cohorts using multivariate regression analysis. RESULTS: A total of 134 patients were identified who underwent TSE after diagnosis of PJI. The mean follow-up was 67.84 (range, 13 to 236) months. Dual setup (odds ratio, 0.13; confidence interval, 0.02 to 0.52; P = 0.0122) was found to be an independent predictive variable associated with a lower risk of infection recurrence. CONCLUSION: Utilization of a dual surgical setup is a low-cost modifiable risk factor associated with a lower risk of recurrence of after TSE of the hip and knee for PJI.

Outcomes of Enterobacter cloacae-Associated Periprosthetic Joint Infection Following Hip Arthroplasties.

Background: Periprosthetic joint infections (PJIs) represent a serious complication following total hip arthroplasty (THA) and are associated with significant morbidity. While recent data suggest that Enterobacter cloacae is an emerging source of PJI, characteristics and outcomes of E. cloacae-associated infections are rarely described. The study aimed to present and describe the findings and outcomes of E. cloacae-associated PJI in our department. Methods: This is a retrospective descriptive study of patients who underwent revision THA for E. cloacae-associated PJI between 2011 and 2020 and has a minimum follow-up of 2 years. Outcomes included organism characteristics as well as clinical outcomes, represented by the number of reoperations needed for PJI eradication and the Musculoskeletal Infection Society (MSIS) outcome reporting tool score. Of 108 revision THAs, 12 patients (11.1%) were diagnosed with E. cloacae-associated PJI. Results: The majority of cases had a polymicrobial PJI (n=8, 66.7%). Five E. cloacae strains (41.7%) were gentamicin-resistant. Six patients (50.0%) underwent 2 or more revisions, while 3 of them (25.0%) required 4 or more revisions until their PJI was resolved. When utilizing the MSIS outcome score, the first surgical intervention was considered successful (MSIS score tiers 1 and 2) for 5 patients (41.7%) and failed (tiers 3 and 4) for 7 patients (58.3%). Conclusions: E. cloacae is emerging as a common source of PJI following hip arthroplasty procedures. The findings of our study suggest that this pathogen is primarily of polymicrobial nature and represents high virulence and poor postoperative outcomes, as represented by both an increased number of required revision procedures and high rates of patients with MSIS outcome scores of 3 and 4. When managing patients with E. cloacae-associated PJI, surgeons should consider these characteristics and inform patients regarding predicted outcomes.

Temporal trends in revision rate due to knee periprosthetic joint infection: a study of 115,120 cases from the Danish Knee Arthroplasty Register.

BACKGROUND AND PURPOSE: We aimed to examine the temporal trends in periprosthetic joint infection (PJI) revision incidence after knee arthroplasty (KA) from 1997 through 2019. PATIENTS AND METHODS: 115,120 primary KA cases from the Danish Knee Arthroplasty Register were followed until the first PJI revision. We computed cumulative incidences and adjusted hazard ratios (aHRs) of PJI revision by calendar periods and several patient- and surgical-related risk factors. Results were analyzed from 0-3 months and from 3-12 months after KA. RESULTS: The overall 1-year PJI revision incidence was 0.7%, increasing from 0.5% to 0.7% (1997 through 2019). The incidence of PJI revision within 3 months increased from 0.1% to 0.5% (1997 through 2019). The adjusted hazard ratio (aHR) within 1 year of primary KA was 5.1 comparing 2017-2019 with 2001-2004. The PJI revision incidence from 3-12 months of KA decreased from 0.4% to 0.2%, with an aHR of 0.5 for 2017-2019 vs. 2001-2004. Male sex, age 75-84 (vs. 65-74), and extreme obesity (vs. normal weight) were positively associated with the risk of PJI revision within 3 months, whereas only male sex was associated from 3-12 months. Partial knee arthroplasty (PKA) vs. total KA was associated with a lower risk of PJI revision both within 3 months and 3-12 months of KA. CONCLUSION: We observed an increase in PJI revision within 3 months of KA, and a decrease in PJI revision incidence from 3-12 months from 1997 through 2019. The reasons for this observed time-trend are thought to be multifactorial. PKA was associated with a lower risk of PJI revision.

Rhodococcus erythropolis septic arthritis.

A woman in her 50s presented with a 4-day history of left knee pain, erythema, swelling as well as malaise and rigours 1 month after undergoing a left knee meniscectomy. She was diagnosed with left native knee septic arthritis and underwent arthroscopic irrigation and debridement of the knee; cultures from synovial tissue grew Rhodococcus erythropolis. Rhodococcus spp are soil-dwelling and livestock-dwelling bacteria which occasionally cause disease in immunocompromised hosts. Infection in immunocompetent hosts is rare, and septic arthritis secondary to Rhodococcus erythropolis has not been reported previously.

Poorer patient-reported outcome and increased risk of revision at a 5-year follow-up among patients with septic arthritis following anterior cruciate ligament reconstruction: a register-based cohort study of 23,075 primary anterior cruciate ligament reconstructions.

PURPOSE: The primary aim of this study is to analyse the patient-reported outcomes after ACLR complicated by septic arthritis. The secondary aim is to examine the 5-year risk of revision surgery after primary ACLR complicated by septic arthritis. The hypothesis was that patients with septic arthritis after ACLR are more likely to have lower PROMs scores and an increased risk of revision, compared with patients without septic arthritis. MATERIALS AND METHODS: All primary ACLRs, with a hamstring or patellar tendon autograft (n = 23,075), in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare to identify patients with postoperative septic arthritis. These patients were verified in a nationwide medical records analysis and compared with patients without infection in the SKLR. The patient-reported outcome was measured using the Knee injury and Osteoarthritis Index Score (KOOS) and the European Quality of Life Five Dimensions Index (EQ-5D) at 1, 2 and 5 years postoperatively and the 5-year risk of revision surgery was calculated. RESULTS: There were 268 events of septic arthritis (1.2%). The mean scores on the KOOS and EQ-5D index were significantly lower for patients with septic arthritis on all subscales on all follow-up occasions compared with patients without septic arthritis. Patients with septic arthritis had a revision rate of 8.2% compared with 4.2% in patients without septic arthritis (adjusted hazard ratio 2.04; confidence interval 1.34-3.12). CONCLUSION: Patients suffering from septic arthritis following ACLR are associated with poorer patient-reported outcomes at 1-, 2- and 5-year follow-ups compared with patients without septic arthritis. The risk of revision ACL reconstruction within 5 years of the primary operation for patients with septic arthritis following ACLR is almost twice as high, compared with patients without septic arthritis. LEVEL OF EVIDENCE: III.