Total joint arthroplasty (TJA) is one of the most successful procedures in orthopaedics. Despite the excellent clinical and functional results, periprosthetic joint infection (PJI) following TJA is a feared complication. For instance, the reported PJI rate after primary total knee arthroplasty is about 0.5–1.9%. In general, prevention of periprosthetic joint and surgical site infections is of utmost importance.

This can be reduced by strict antisepsis, adequate sterilization of the surgical instruments and meticulous surgical technique. An indisputable role in prevention of SSI in TJA has been the use of peri-operative systemic antibiotic prophylaxis. The most common recommended antibiotics for prophylaxis in TJA are cefazolin or cefuroxime. In contrast, routine use of commercial antibiotic-loaded bone cement (ALBC) in primary total joint arthroplasty is still a concern of open debate. The use of antibiotic-loaded bone cement delivers a high concentration of antibiotics locally and can decrease the infection rate, which is supported by several studies in the literature. In this context, we present the pros of routine use of commercial antibiotic-loaded bone cement.

Despite the demonstrated success in revision total joint arthroplasties, the utilization of antibiotic-loaded bone cement in primary total joint arthroplasty remains controversial. Multiple studies have demonstrated several risks associated with the routine use of this technique including: allergic reactions, changing the mechanical properties of the cement, emergence of resistant bacterial strains, systemic toxicity, and the added cost. In addition, evidence shows a currently low rate of periprosthetic joint infections in primary total joint arthroplasty (around 1%) and the theoretical benefit of marginally reducing this rate by using antibiotic-cement may not necessarily justify the associated risks and the added cost. Moreover, most of the primary total hip and an increasing number of primary total knee arthroplasties are cementless, which further raises questions about the routine use of antibiotic-loaded bone cement in primary total joint arthroplasty.

Despite the prophylactic use of antibiotics and hygienic strategies, surgical site infection following total joint arthroplasty (TJA) is still a severe and unsolved complication. Since antibiotic-loaded bone cement (ALBC) was introduced by Buchholz in the 1970s, the use of ALBC has been increasingly used for the prevention and treatment of periprosthetic infection (PPI). However, the routine use of ALBC during primary TJA remains controversial. Recent clinical studies have found that ALBC is effective in reducing the risk of PJI following primary TJA. Although ALBC having the advantage of reducing the risk of PJI, the main disadvantages are the possible development of toxicity, antibiotic resistance, allergic reaction, and possible reduction of the mechanical properties of bone cement. Nevertheless, a recent published article demonstrated, that the use of high dose dual-antibiotic impregnated cement reduce significantly the rate of surgical site infections compared to standard low dose single ALBC in the setting of a hip fracture treating with hemiarthroplasty. Furthermore, Sanz-Ruiz et al. presented that the use of ALBC in TJA has favorable cost-efficiency profile. In this context, reasons why surgeons should use antibiotic-loaded bone cement during primary TJA are demonstrated

Aim. Whether laminar airflow (LAF) in the operating room (OR) is effective for decreasing periprosthetic joint infection (PJI) following total joint arthroplasty (TJA) remains a clinically significant yet controversial issue. This study investigated the association between operating room ventilation systems and the risk of PJI in TJA patients. Method. We performed a retrospective observational study on consecutive patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) from January 2013-September 2017 in two surgical facilities within a single institution, with a minimum 1-year follow-up. All procedures were performed by five board-certified arthroplasty surgeons. The operating rooms at the facilities were equipped with LAF and turbulent ventilation systems, respectively. Patient characteristics were extracted from clinical records. PJI was defined according to Musculoskeletal Infection Society criteria within 1-year of the index arthroplasty. A multivariate logistic regression model was performed to explore the association between LAF and risk of 1-year PJI, and then a sensitivity analysis using propensity score matching (PSM) was performed to further validate the findings. Results. A total of 6,972 patients (2,797 TKA, 4,175 THA) were included. The incidence of PJI within 1 year for patients from the facility without laminar flow was similar at 0·4% to that of patients from the facility with laminar flow at 0·5%. In the multivariate logistic regression analysis, after all confounding factors were taken into account, the use of LAF was not significantly associated with reduction of the risk of PJI. After propensity score matching, there was no significant difference in the incidence of PJI within 1 year for patients between the two sites. Conclusions. The use of LAF in the operating room was not associated with a reduced incidence of PJI following primary TJA. With an appropriate perioperative protocol for infection prevention, LAF does not seem to play a protective role in PJI prevention

Aim. While metagenomic (microbial DNA) sequencing technologies can detect the presence of microbes in a clinical sample, it is unknown whether this signal represents dead or live organisms. Metatranscriptomics (sequencing of RNA) offers the potential to detect transcriptionally “active” organisms within a microbial community, and map expressed genes to functional pathways of interest (e.g. antibiotic resistance). We used this approach to evaluate the utility of metatrancriptomics to diagnose PJI and predict antibiotic resistance. Method. In this prospective study, samples were collected from 20 patients undergoing revision TJA (10 aseptic and 10 infected) and 10 primary TJA. Synovial fluid and peripheral blood samples were obtained at the time of surgery, as well as negative field controls (skin swabs, air swabs, sterile water). All samples were shipped to the laboratory for metatranscriptomic analysis. Following microbial RNA extraction and host analyte subtraction, metatranscriptomic sequencing was performed. Bioinformatic analyses were implemented prior to mapping against curated microbial sequence databases– to generate taxonomic expression profiles. Principle Coordinates Analysis (PCoA) and Partial Least Squares-Discriminant Analysis were utilized to ordinate metatranscriptomic profiles, using the 2018 definition of PJI as the gold-standard. Results. After RNA metatranscriptomic analysis, blinded PCoA modeling revealed accurate and distinct clustering of samples into 3 separate cohorts (infected, aseptic, and primary joints) – based on their active transcriptomic profile, both in synovial fluid and blood (synovial anosim p=0.001; blood anosim p=0.034). Differential metatranscriptomic signatures for infected versus noninfected cohorts enabled us to train machine learning algorithms to 84.9% predictive accuracy for infection. Multiple antibiotic resistance genes were expressed, with high concordance to conventional antibiotic sensitivity data. Conclusions. Our findings highlight the potential of metatranscriptomics for infection diagnosis. To our knowledge, this is the first report of RNA sequencing in the orthopaedic literature. Further work in larger patient cohorts will better inform deep learning approaches to improve accuracy, predictive power, and clinical utility of this technology

Introduction. Reducing readmissions after total joint arthroplasty (TJA) is challenging. Pre-operative risk stratification and optimization pre surgical care may be helpful in reducing readmission rates after primary TJA. Assessment of the predictive value of individual modifiable risk factors without a tool to properly stratify patients may not be helpful to the surgical community to reduce the risk of readmission. We developed a scoring system: Readmission Risk Assessment Tool (RRAT) as part of a Perioperative Orthopaedic Surgical Home model that allows for risk stratification in patients undergoing elective primary TJA at our institution. We analyzed the relationship between the RRAT score and readmission following primary hip or knee arthroplasty. Methods. The RRAT, which is scored incrementally based on the number and severity of modifiable comorbidities was used to generate readmission scores for a cohort of 207 readmitted and 2 cohorts of 234 (random and age-matched) non-readmitted patients each. Regression analysis was performed to assess the strength of association between individual risk factors, RRAT score and readmissions. We also calculated the odds and odds ratio (OR) at each level of RRAT score to identify patients with relatively higher risk of readmission. Results. There were 207(2.08%) 30-day readmissions in 9,930 patients over a 6-year period (2008 to 2013). Surgical site infection was the most common cause of readmission (93 cases, 45%). The median RRAT scores were 3 (IQR: 1, 4) and 1 (IQR: 0, 2) for readmitted group and non-readmitted group respectively. The RRAT score was significantly associated with readmission with odds ratio between 1.5 and 1.9 under various model assumptions. A RRAT score of 3 or higher resulted in higher odds of readmission. Discussion and Conclusion. Population health management, cost-effective care and optimization of outcomes to maximize value are the new maxims for healthcare delivery in the United States. The RRAT has a significant association with readmission following joint arthroplasty and could potentially be a clinically meaningfully tool for risk mitigation

Total joint arthroplasty (TJA) is often utilized to improve pain and dysfunction associated with end-stage osteoarthritis. Previous research has suggested that depression may negatively impact patient reported pain and function. The purpose of this study was to determine the effect of pre-operative depressive symptoms, using the Center for Epidemiologic Scale for Depression (CES-D) scale, on patient reported function and pain at one, three and six months following TJA, after controlling for the impact of age, sex, pain, joint replaced, and other comorbidities. This was a secondary analysis of a prospective cohort of 710 patients aged 40 years and older who underwent elective primary TJA in the Edmonton zone. Participants were recruited pre-operatively and reported socio-demographics, comorbid conditions and medications (including depression medications where appropriate), each participant also completed the Western Ontario McMaster (WOMAC) Osteoarthritis Index and the CES-D scale preoperatively. Participants then completed the WOMAC and CES-D scale again at one, three, and six months postoperatively. Risk-adjusted longitudinal data analysis using a linear mixed regression model was performed, controlling for age, sex, joint replaced, chronic pain, comorbidity, social support and employment status. THA participants had a mean age of 65.9±10.1 years and included 175 (57%) female while TKA participants had a mean age of 67.9±10.1 years and included 249 (61%) females. ‘Possible’ depressive symptoms (CES-D score 16–19) were identified in 58 (8.1%) participants while ‘probable’ depressive symptoms (CES-D score ≥20) were identified in 68 (9.6%) participants. The mean WOMAC pain and function scores, when analyzed using the linear mixed regression model, demonstrated improvement from baseline at one, three, and six months (p < 0 .001 for both pain and function models as well as over time). However, in the patients with possible and probable depressive symptoms, WOMAC pain scores were 7.6±1.5 and 11.7±1.3 worse respectively than those without depressive symptoms after controlling for age, sex, joint replaced, chronic pain, comorbidities and social support. Similarly, WOMAC function scores in the patients with possible and probable depressive symptoms were 8.8±1.4 and 14.2±1.2 worse respectively than those without depressive symptoms after controlling for age, sex, joint replaced, comorbidities and employment status. Depressive symptoms negatively affect postoperative pain and function measured using WOMAC scales even after risk adjustment up to six-months post TJA. Screening for depressive symptomology both pre- and postoperatively may provide an opportunity to identify and manage depressive symptoms to improve postoperative pain and function

Total joint arthroplasty (TJA) is often utilized to improve pain and dysfunction associated with end-stage osteoarthritis. Previous research has suggested that depression may negatively impact patient reported pain and function. The purpose of this study was to determine the effect of preoperative depressive symptoms, using the Center for Epidemiologic Scale for Depression (CES-D) scale, on patient reported function and pain at one, three and six months following TJA, after controlling for the impact of age, sex, pain, joint replaced, and other comorbidities. This was a secondary analysis of a prospective cohort of 710 patients aged 40 years and older who underwent elective primary TJA in the Edmonton zone. Participants were recruited pre-operatively and reported socio-demographics, comorbid conditions and medications (including depression medications where appropriate), each participant also completed the Western Ontario McMaster (WOMAC) Osteoarthritis Index and the CES-D scale preoperatively. Participants then completed the WOMAC and CES-D scale again at one, three, and six months postoperatively. Risk-adjusted longitudinal data analysis using a linear mixed regression model was performed, controlling for age, sex, joint replaced, chronic pain, comorbidity, social support and employment status. THA participants had a mean age of 65.9±10.1 years and included 175 (57%) female while TKA participants had a mean age of 67.9±10.1 years and included 249 (61%) females. ‘Possible’ depressive symptoms (CES-D score 16–19) were identified in 58 (8.1%) participants while ‘probable’ depressive symptoms (CES-D score ≥20) were identified in 68 (9.6%) participants. The mean WOMAC pain and function scores, when analyzed using the linear mixed regression model, demonstrated improvement from baseline at one, three, and six months (p < 0 .001 for both pain and function models as well as over time). However, in the patients with possible and probable depressive symptoms, WOMAC pain scores were 7.6±1.5 and 11.7±1.3 worse respectively than those without depressive symptoms after controlling for age, sex, joint replaced, chronic pain, comorbidities and social support. Similarly, WOMAC function scores in the patients with possible and probable depressive symptoms were 8.8±1.4 and 14.2±1.2 worse respectively than those without depressive symptoms after controlling for age, sex, joint replaced, comorbidities and employment status. Depressive symptoms negatively affect postoperative pain and function measured using WOMAC scales even after risk adjustment up to six-months post TJA. Screening for depressive symptomology both pre- and postoperatively may provide an opportunity to identify and manage depressive symptoms to improve postoperative pain and function

Early mobilization within the first 12 hours (day zero) of total joint arthroplasty (TJA) has been shown to reduce length of stay (LoS) without risking clinical outcomes, patient safety or satisfaction. The purpose of this study was to investigate associations between the degree of mobilization on day zero (i.e., standing at the bedside versus walking in the hallway) and LoS in TJA patients. In addition, we investigated predictors of LoS and day zero mobilization. A retrospective cohort study was undertaken of the health records of patients in a community hospital setting who had an elective unilateral primary TJA between June 2015 and May 2017 and had mobilized on day zero. The total sample was 283 patients (184 TKA and 99 THA) across four mobilization categories: Sat on beside (n = 76), Stood by bed/marched in place (n = 83), Walked in the room (n = 79), and Walked in hall (n = 45). Analysis of variance found no significant group differences in age, ASA score, Charlson Comorbidity Index score, anesthesia, surgeon, procedure type, pain medication, and patient reported symptoms recorded by physiotherapists. Significantly more women were in the Sat group and significantly more men were in the Hall group (p < .001). Patient reported symptoms of nausea and drowsiness were significantly greater for the Sat group (p < .001). LoS was also significantly different across the groups. Post hoc Tukey comparisons found the Walked Hall group had significantly shorter LoS (M = 2.7 days) than the Sat group (M = 3.9, p < .001), Stood group (M = 3.4, p = .011), and the Walked Room group (M = 3.5, p = .004). A hierarchical regression was performed to determine predictors of LoS. Block 1 consisted of demographic, medical status, and patient reported symptoms as variables. Mobilization was entered in Block 2. The first model was significant (p < .001) and explained 24% of variance in LoS. The final model was also significant (p < .001), accounting for a total of 26% of the variance in LoS. Thus, block 2 (i.e., mobilization) accounted for a small but significant 2% incremental variance (p = .008) beyond the block 1 variables in the prediction of LoS. With mobilization added, only male gender (p = .002), lower BMI (p = .026), and lower ASA scores (p = .006) remained significant predictors of shorter LoS, and the predictive ability of several of the block 1 variables were reduced to non-significant levels. A simultaneous regression model was then used to predict degree of mobilization. The model accounted for 24% of the variance in mobilization (p < .001). Variables significantly associated with a greater degree of mobilization included: younger age, male gender, lower BMI, and fewer symptoms, namely nausea, numbness, lightheadedness, and drowsiness. This study found length of stay was shorter when patients mobilized farther on the day of surgery. Some factors predictive of mobilization may be modifiable. Focusing on symptom management could increase opportunities for farther mobilization on the day of surgery, and thus decrease length of stay

Background: Metal sensitivity following total joint arthroplasty (TJA) has been of increased concern, but the impact of a patient-reported metal allergy on clinical outcomes has not been investigated. The purpose of this study was to report the incidence and impact of patient-reported metal allergy following total knee (TKA) and total hip arthroplasty (THA). Methods: This was a retrospective, IRB-approved investigation of patients undergoing a primary, elective TJA between 2009 and 2011. All patients completed a pre-operative questionnaire asking about drug and environmental allergies. In January of 2010, a specific question was added regarding the presence of a metal allergy. UCLA Activity, SF-12, Modified Harris Hip (MHHS), and Knee Society (KSS) scores were collected pre-operatively and at most recent follow-up. Overall cohorts of metal allergy and non-metal allergy patients were compared and a 1:2 matching analysis was also performed. Results: 906 primary THAs and 589 primary TKAs were included. The incidence of patient-reported metal allergy was 1.7% before January 2010 and 4.0% after (overall 2.3% of THAs and 4.1% of TKAs). 97.8% of metal allergy patients were female. Following TKA, post-operative KSS function, symptoms, satisfaction, and expectation scores were all decreased in the metal allergy cohort (p<0.001 to 0.002). Following THA, metal allergy patients had a decreased post-operative SF-12 MCS score and less incremental improvement in their SF-12 MCS score versus the non-metal allergy cohort (p<0.0001 and p<0.001). Conclusion: Patient-reported metal allergy is associated with decreased functional outcomes following TKA and decreased mental health scores following THA