What Factors Influence In-Hospital Mortality Following Aseptic Revision Total Hip Arthroplasty? A Single-Center Analysis of 13,203 Patients.

BACKGROUND: Revision total hip arthroplasty (rTHA) is associated with an extended surgical period, an increased hospitalization period, expanded blood loss, and high mortality rates. The purpose of the present study was to assess the risk factors that contribute to in-hospital mortality following aseptic rTHA. METHODS: We performed a retrospective examination of the medical records of all patients who underwent elective rTHA surgery at our tertiary referral arthroplasty center between March 1996 and March 2019. The study involved a group of 13,203 patients, including 70 who expired during hospitalization and 13,133 in the control group. Baseline characteristics, medical history, comorbidities, and surgery-related parameters of the patients were recorded. Logistic regression analyses were performed to examine the association between independent variables and in-hospital mortalities, which were presented as odds ratios (ORs) and confidence intervals (CIs). RESULTS: Patient factors associated with in-hospital mortality included hepatitis C (OR 75.5, 95% CI 3.5 to 1,625.2), chronic obstructive pulmonary disease (OR 30.7, 95% CI 6.5 to 145.7), rheumatoid arthritis (OR 28.9, 95% CI 3.8 to 218.5), history of myocardial infarction (OR 24.9, 95% CI 4.4 to 140.8), history of cerebrovascular disease (OR 23.1, 95% CI 3.8 to 142), congestive heart failure (OR 18.9, 95% CI 3.8 to 94.2), and diabetes mellitus (OR 10.2, 95% CI 2.4 to 42.6). Surgical factors included the history of multiple prior revisions (OR 1.75, 95% CI 1.1 to 2.7), postoperative blood transfusion (OR 2.8, 95% CI 1.1 to 7.3), and decreased preoperative hemoglobin (OR 2.3, 95% CI 1.7 to 3.1). CONCLUSIONS: Several patient-related and intraoperative factors significantly increased the risk of in-hospital mortality following aseptic rTHA. Vigilance and close perioperative monitoring are essential for patients undergoing this complex surgery. LEVEL OF EVIDENCE: III.

Risk Factors and Microbiological Profile of Knee Periprosthetic Joint Infections With Sinus Tract.

BACKGROUND: A sinus tract is an abnormal channel that communicates between the skin and the joint, and meets one of the major criteria that is diagnostic of periprosthetic joint infection (PJI). The purpose of this study was to compare the risk factors and the microorganism profile of PJI of the knee with an overlying sinus tract to PJI without a sinus tract. METHODS: This was a retrospective case-control study of PJI following total knee arthroplasty with and without the presence of an overlying sinus tract from 1996 to 2020. There were 2,685 unique cases of chronic PJI following total knee arthroplasty, of which 405 cases (15.1%) had a sinus tract and 2,280 cases (84.9%) did not. Univariate and multivariate analyses were performed to evaluate risk factors and the microorganism profiles of the 2 groups. Odds ratios with 95% confidence intervals were reported. RESULTS: After adjusting for potential confounders in the multivariate analysis, the presence of a sinus tract was associated with a history of severe liver disease (P = .039; odds ratio: 1.99; 95% confidence interval: 1.04 to 3.84). Polymicrobial infections comprised 41.7% of PJI in the sinus tract group, compared to 29.1% in patients who did not have a sinus tract (P < .001). Of the monomicrobial PJI, Staphylococcus aureus (P < .001), Enterococcus faecalis (P < .001), Enterobacter cloacae (P = .002), Corynebacterium species (P = .037), Proteus mirabilis (P = .028), coagulase-negative Staphylococci (P = .019), and Candida albicans (P = .029) were more common in patients who had a sinus tract. CONCLUSIONS: The microbiology profile is significantly different in patients who have PJI of the knee with a sinus tract. These findings can guide the surgeon with surgical planning and selecting the appropriate antibiotic-loaded bone cement and empiric antibiotic treatment.

Microbial Diversity of Periprosthetic Joint Infections in Diabetic and Nondiabetic Patients Following Hip Arthroplasty.

BACKGROUND: Periprosthetic joint infection (PJI) is a major complication following hip arthroplasty, leading to prolonged hospital stays, increased health care costs, and major morbidity. Diabetes mellitus is a prevalent comorbidity among hip arthroplasty patients, contributing to an increased risk of surgical complications, including infections. However, limited evidence exists regarding the microbial profiles of PJIs in diabetic patients compared to nondiabetic counterparts. METHODS: We conducted a retrospective cohort study to investigate the microbial diversity of PJIs in diabetic and nondiabetic patients following hip arthroplasty. Medical records of patients who underwent hip arthroplasty procedures between 1996 and 2021 were reviewed. Patients diagnosed with PJI, based on the international consensus meeting, were included in the study. Microbiological data, including culture results, and risk factors were collected and analyzed. A total of 4,261 culture-positive patients diagnosed with PJI following hip arthroplasty were included in the analysis. RESULTS: Microbiological analysis revealed a diverse spectrum of microbial pathogens, with Staphylococcus species being the most commonly isolated pathogen. Comparison between diabetic and nondiabetic patients revealed differences in the microbial profiles of PJIs, with diabetic patients more likely to be infected with specific pathogens, including Candida albicans (P = 0.01 odds ratio (OR) 2.8, confidence interval (CI) 1.2 to 6.2), Klebsiella pneumoniae (P = 0.03 OR 2.4, CI 1.0 to 5.6), Staphylococcus aureus (P = 0.04 OR 1.3, CI 1.0 to 1.8), Staphylococcus epidermidis (P < 0.001 (R 1.7, CI 1.4 to 2.2), Polymicrobial infections (P < 0.001 OR 1.5, CI 1.2 to 1.8), and Clostridium perfringens (P = 0.04 OR 5.9, CI 1.0 to 33.1). CONCLUSIONS: Our study provides valuable insights into the microbial diversity of PJIs in diabetic and nondiabetic patients following hip arthroplasty. The identification of a tendency to different microbial profiles in diabetic patients underscores the need for tailored approaches to infection prevention and management in this high-risk population. Further research is needed to elucidate the underlying mechanisms and develop targeted interventions to improve patient outcomes.

Increased Involvement of Staphylococcus epidermidis in the Rise of Polymicrobial Periprosthetic Joint Infections.

BACKGROUND: In this study, we aimed to analyze the temporal distribution of polymicrobial periprosthetic joint infections (PJIs), while also evaluating the patient risk factors associated with these infections following total joint arthroplasty at our institution across 2 distinct periods. METHOD: This retrospective cross-sectional study evaluated 259 patients who had knee or hip PJI from 2001 to 2006 and 2018 to 2022. A PJI was diagnosed using the 2018 International Consensus Meeting criteria. We utilized the Polymicrobial Pathogens' Co-occurrence Network Analysis, a novel approach that leverages network theory to map and quantify the complex interplay of organisms in PJIs. RESULTS: Of the 259 patients who had polymicrobial PJI, 58.7% were men, with mean age 67 years (range, 24 to 90). Of the 579 identified pathogens, Staphylococcus epidermidis was the most common (22.1%), followed by Staphylococcus aureus (9.0%) and Cutibacterium acnes (7.8%). The co-occurrence analysis indicated that Staphylococcus epidermidis frequently coexisted with Cutibacterium acnes (26 cultures) and Staphylococcus capitis (22 cultures). A notable increase in body mass index from 27.7 ± 4.4 in 2001 to 2006 to 29.7 ± 6.2 in 2018 to 2022 was observed (P = .001). Moreover, infections from Staphylococcus epidermidis, Cutibacterium acnes, and Staphylococcus capitis saw a significant uptick (P < .001). CONCLUSIONS: The study shows that from 2001 to 2022, there was a significant change in the pathogens responsible for polymicrobial PJIs, particularly an increase in Staphylococcus epidermidis, Cutibacterium acnes, and Staphylococcus capitis. Alongside these microbial changes, there was a rise in body mass index and shifts in comorbid conditions, such as more renal disease and fewer cases of congestive heart failure. These changes highlight the dynamic interplay between host and microbial factors in the pathogenesis of polymicrobial PJIs, necessitating adaptive strategies in both surgical and postoperative care to mitigate the rising tide of these complex infections.

Microbiological profiles in periprosthetic joint infections after total knee arthroplasty: a comparative analysis of diabetic and non-diabetic patients.

AIM OF THE STUDY: The purpose of this study is to conduct a comparative analysis of the microbiological profiles in periprosthetic joint infections (PJIs) after total knee arthroplasty (TKA) between diabetic and non-diabetic patients. The study aims to address what are the variations in microbial colonization and infection patterns between diabetic and non-diabetic patients undergoing total knee arthroplasty. METHODS: A retrospective analysis of 2,569 culture-positive cases of PJIs post-TKA was conducted, comparing outcomes between diabetic (n = 321) and non-diabetic (n = 2,248) patients. Demographic, clinical, and microbiological data were collected and analyzed using descriptive statistics, chi-squared tests, logistic regression, and other statistical tests. RESULTS: Diabetic patients exhibited distinct microbial colonization patterns, with a higher prevalence of pathogens such as Staphylococcus aureus (p = 0.033), Pseudomonas aeruginosa (p < 0.001), Streptococcus spp. (Streptococcus agalactiae and Streptococcus dysgalactiae; p = 0.010, 0.016 respectively), Candida spp. (p = 0.010), and Corynebacterium spp. (p = 0.024). Additionally, diabetic patients were at increased risk of polymicrobial infections. Comorbidities associated with diabetes, including chronic pulmonary disease, renal insufficiency, and peripheral artery disease, were significantly more prevalent in diabetic patients and further complicated PJI outcomes. CONCLUSION: This study underscores the importance of tailored perioperative antimicrobial strategies and vigilant infection control measures in diabetic patients undergoing TKA. Understanding the differential microbial profiles and associated comorbidities can inform targeted interventions to mitigate the risk of PJIs and improve outcomes in this high-risk population. Further research is warranted to elucidate the underlying mechanisms and optimize management strategies for diabetic patients undergoing TKA.

How reliable is the soft tissue radiological knee index in predicting superficial surgical site infection following total knee arthroplasty?

INTRODUCTION: The purpose of this study was to evaluate the association between the Soft Tissue Radiological Knee (SToRK) Index and the risk of developing a superficial surgical site infection (SSSI) following primary total knee arthroplasty (TKA). METHODS: The SToRK Index was measured using calibrated long leg radiographs (LLR) in 174 patients undergoing TKA. RESULTS: A moderate correlation was found between the SToRK Index and body mass index (BMI) (rs=0.574; p < 0.001). The SToRK Index was a better predictor of SSSI in females than males. In females, a SToRK Index cutoff of 2.01 had a sensitivity and specificity of 41.3% and 74.6% for developing SSSI, respectively, with a positive likelihood ratio of 1.63. CONCLUSION: The SToRK Index can be used as an additional tool in assessing the risk for SSSI after TKA. It might be more predictive in females due to the different fat distribution compared to males.

Unexpected Positive Cultures in Patients Who Have a History of Septic Revision in the Same Joint.

BACKGROUND: The prevalence of unexpected positive cultures (UPC) in an aseptic revision surgery of the joint with a prior septic revision in the same joint remains unknown. The purpose of this study was to determine the prevalence of UPC in that specific group. As secondary outcomes, we explored risk factors for UPC. METHODS: This retrospective study includes patients who had an aseptic revision total hip/knee arthroplasty procedure with a prior septic revision in the same joint. Patients who had less than 3 microbiology samples, without joint aspiration or with aseptic revision surgery performed <3 weeks after a septic revision were excluded. The UPC was defined as a single positive culture in a revision that the surgeon had classified as aseptic according to the 2018 International Consensus Meeting. After excluding 47, a total of 92 patients were analyzed, who had a mean age of 70 years (range, 38 to 87). There were 66 (71.7%) hips and 26 (28.3%) knees. The mean time between revisions was 83 months (range, 31 to 212). RESULTS: We identified 11 (12%) UPC and in 3 cases there was a concordance of the bacteria compared to the previous septic surgery. There were no differences for UPC between hips/knees (P = .282), diabetes (P = .701), immunosuppression (P = .252), previous 1-stage or 2-stages (P = .316), causes for the aseptic revision (P = .429) and time after the septic revision (P = .773). CONCLUSION: The prevalence of UPC in this specific group was similar to those reported in the literature for aseptic revisions. More studies are needed to better interpret the results.

Is the Citak classification of distal femur morphology age and gender dependent?

INTRODUCTION: The purpose of this study was to compare the distal femur morphology in different age and gender groups using the Citak classification. MATERIALS AND METHODS: All patients who had standard knee anteroposterior radiographs between 2010 and 2020 were retrospectively reviewed using the electronic patient database. Patients were divided into three age groups as follows: young adults (Group I, younger than 50 years), middle-aged adults (Group II, ranging from age 51 to 73 years), and elderly (Group III, more than 74 years). From each age group, 80 patients were randomly selected with an equal number of gender (40 males/40 females). An age-stratified selection was applied to obtain the best sample that represents the selected age groups. Patients younger than 18 years of age, history of previous fracture or surgical procedure, those with fixation implants or prosthesis, and abnormalities of the lower limb, such as a congenital deformity, were excluded from the study. All measurements were performed by an experienced orthopedic surgeon familiar with the Citak classification. All measured variables were compared between age and gender groups. RESULTS: There were 240 patients (120 male and 120 female) with a mean age of 59.6 ± 20.4 (range 18-95). The distal femur morphology index was similar (p:0.811), and the morphological types were equally distributed among age groups (p:0.819). Furthermore, there was no significant difference between genders on the measured variables (p > 0.05 for all variables). Citak classification types were similarly distributed between the genders (p:0.153). No correlation was found between age and the Citak index in either gender (p:0.967 and p:0.633, respectively). CONCLUSIONS: Distal femoral morphology classified by the Citak index is not age and gender dependent. Type C, which has a wider diaphyseal diameter, and is supposed to be more common in elderly subjects, was equally distributed in all age groups. LEVEL OF EVIDENCE: Level IV. Retrospective case series.

Long-term outcomes of total hip arthroplasty in patients with developmental dysplasia of the hip: a minimum 21-year follow-up.

PURPOSE: Early osteoarthritis (OA) due to developmental dysplasia of the hip (DDH) is a known indication for total hip arthroplasty (THA). Though screening tools and joint-preserving procedures have been established successfully, there still is a relevant number of patients suffering DDH. Due to the lack of long-term outcome studies, we like to close this gap and present the results of a highly specialized center. METHODS: The study included 126 patients, who were treated in our institution with primary THA for DDH between January 1997 and December 2000. At the time of final follow-up, at a mean of 23 years postoperatively, 110 patients (121 hips) were clinically evaluated using the Harris-Hip Score. In addition, complication and surgical revision rates were assessed. We collected surgery-related data like implant choice and special surgical features such as autologous acetabular reconstruction or femoral osteotomies. Additionally, the severity of preoperative DDH was measured radiographically according to Crowe classification. RESULTS: There were 91 female (83%) and 19 male (17%) patients with an average age of 51 ± 9.5 years (range 21-65) included. Mean follow-up was 23 ± 1.3 years (21-25), with a minimum of 21 years being necessary for inclusion. Using revision for any indication as primary endpoint, the Kaplan-Meier survivorship was 98.3% at 10 years and 81.8% at final follow-up. The overall revision rate was 18% (22 cases), which were split up as follows: 20 (17%) implant failures (loosened or broken components), one (1%) periprosthetic infection and one (1%) periprosthetic fracture. Regarding complications, we observed nine (7%) dislocations and one case (1%) with severe heterotopic ossification that required surgical excision. The mean Harris-Hip score at latest follow-up was 78 ± 14 points (32-95). CONCLUSIONS: Though implants and surgical techniques have improved over time, our results suggest THA in patients suffering DDH to be seriously challenging with relatively high overall complications in long-term observation and fair clinical outcome after 21 years postoperatively. There is evidence that prior osteotomy might be associated with a higher revision rate.

Comparison of Patient-Reported Outcomes Measures and Quality-Adjusted Life Years Following One- and Two-Stage Septic Knee Exchange.

(1) Background: Periprosthetic joint infection (PJI) can be managed with one- or two-stage revision surgery protocol. Despite several studies analyzing the eradication rates between both procedures, there are no comparative studies that analyze patient-reported outcome measures (PROMs) and quality-adjusted life years (QALYs) in both treatment strategies. (2) Methods: All patients who underwent a two-stage knee revision between January 2017 to December 2018, due to a periprosthetic joint infection were included in the study. From the time interval, we selected a comparative group with the one-stage septic procedure. All patients received the following questionnaires: Oxford Knee Score, EQ-5D-5L, SSQ-8, and the SF-36. Additionally, demographic patient data were collected. The quality-adjusted life years (QALY) were calculated using the EQ-5D-5L. (3) Results: A total of 35 patients with a mean age of 67.7 years (SD = 8.9) were included in the final evaluation. The mean follow-up period was 54.5 months (SD = 5.5). There was no statistically significant difference regarding the Charlson Comorbidity Index (CCI), postoperative complications, or all evaluated questionnaires. There was no statistically significant difference in QALYs between the one- and two-stage revision. (4) Conclusion: Our study results show that the one-stage revision for PJI achieves similar PROMs compared to two-stage revision.