Aim. Chronic bone infections and infected fractures are often treated with excision of the dead bone and implantation of biomaterials which elute antibiotics. Gentamicin has been a preferred drug for local delivery, but this could induce renal dysfunction due to systemic toxicity. This is a particular concern in patients with pre-existing chronic renal disease treated with new antibiotic carriers which achieve very high peak levels of gentamicin in the first few days after surgery. Method. 163 patients (109 males; average age 51.6 years) with Cierny-Mader Type 3 or 4 chronic osteomyelitis had a single-stage operation with excision of the dead bone, filling of the osseous defect with a calcium sulphate-hydroxyapatite carrier, containing gentamicin and immediate soft tissue closure. 2. No patient was given systemic gentamicin or other renal toxic antibiotics. Mean carrier volume was 10.9mls (range 1–30mls) and mean gentamicin dosing was 190.75mg (maximum 525mg). Seven patients had pre-existing renal disease (4 diabetic nephropathy, 1 nephrotic syndrome, 1 renal transplant and 1 previous acute kidney injury). Serum creatinine levels were collected pre-operatively and during the first seven days post-operatively. Glomerular filtration rate (GFR) was calculated using the CKD-epi creatinine equation. Renal function was defined using the Chronic Kidney Disease (CKD) Staging system. Results. 155 cases had adequate data to allow calculation of pre- and post-operative GFR. Pre-operative CKD staging demonstrated 118 Class I (normal renal function), 30 Class II, 3 Class IIIa, 3 Class IIIb, and 1 Class V disease. Mean pre-operative GFR (99.7ml/min/1.73m. 2. , SD 21.0) was no different to post-operative GFR (103.2ml/min/1.73m. 2. , SD 21.3), p= 0.0861. Four cases had a >10% decline in GFR below normal, with only one case dropping a CKD stage, from I (normal) to II (mildly decreased). Only 1/7 cases with pre-existing renal disease had a GFR drop of >10% (from 11ml/min/1.73m. 2. to 8ml/min/1.73m. 2. ). 70/155 (45.2%) had a temporary GFR drop post-operatively, with the biggest drop occurring a mean 3.06 days following surgery (SD 2.1). No patient had clinical signs of new acute renal impairment post-operatively. Conclusions. Renal function is not significantly affected by local implantation of gentamicin up to 525mg. The presence of pre-existing renal disease is not a contraindication to local gentamicin therapy

Aims. Medical comorbidities are a critical factor in the decision-making process for operative management and risk-stratification. The Hierarchical Condition Categories (HCC) risk adjustment model is a powerful measure of illness severity for patients treated by surgeons. The HCC is utilized by Medicare to predict medical expenditure risk and to reimburse physicians accordingly. HCC weighs comorbidities differently to calculate risk. This study determines the prevalence of medical comorbidities and the average HCC score in Medicare patients being evaluated by neurosurgeons and orthopaedic surgeon, as well as a subset of academic spine surgeons within both specialities, in the USA. Methods. The Medicare Provider Utilization and Payment Database, which is based on data from the Centers for Medicare and Medicaid Services’ National Claims History Standard Analytic Files, was analyzed for this study. Every surgeon who submitted a valid Medicare Part B non-institutional claim during the 2013 calendar year was included in this study. This database was queried for medical comorbidities and HCC scores of each patient who had, at minimum, a single office visit with a surgeon. This data included 21,204 orthopaedic surgeons and 4,372 neurosurgeons across 54 states/territories in the USA. Results. Orthopaedic surgeons evaluated patients with a mean HCC of 1.21, while neurosurgeons evaluated patients with a mean HCC of 1.34 (p < 0.05). The rates of specific comorbidities in patients seen by orthopaedic surgeons/neurosurgeons is as follows: Ischemic heart disease (35%/39%), diabetes (31%/33%), depression (23%/31%), chronic kidney disease (19%/23%), and heart failure (17%/19%). Conclusion. Nationally, comorbidity rate and HCC value for these Medicare patients are higher than national averages for the US population, with ischemic heart disease being six-times higher, diabetes two-times higher, depression three- to four-times higher, chronic kidney disease three-times higher, and heart failure nine-times higher among patients evaluated by orthopaedic surgeons and neurosurgeons. Cite this article: Bone Joint Open 2020;1-6:257–260

Introduction. The treatment of chronic bone infection often involves excision of dead bone and implantation of biomaterials which elute antibiotics. Gentamicin is a preferred drug for local delivery, but its systemic use carries a well-established risk of nephrotoxicity. We aim to establish the risk of renal injury with local delivery in a ceramic carrier. Materials and Methods. 163 consecutive patients with Cierny-Mader Type 3 or 4 chronic osteomyelitis were treated with a single-stage operation which included filling of the osseous defect with a calcium sulphate-hydroxyapatite carrier containing gentamicin. The mean carrier volume used was 10.9mls, leading to a mean implanted gentamicin dose of 191.3mg (maximum 525mg). Serum creatinine levels were collected pre-operatively and during the first seven days post-operatively. Renal impairment was graded using the Chronic Kidney Disease (CKD) Staging system, and AKI was assessed using the RIFLE criteria. Results. 155 cases had adequate data to allow calculation of pre- and post-operative GFR. 7 patients had pre-existing renal disease. 70 patients (45.2%) had a temporary eGFR drop post-operatively, with the greatest decrease occurring a mean 3.06 days following surgery. Twenty cases had a >10% decline in eGFR, but 12 resolved within 7 days. 7 patients transiently fell into the “Risk” category according to RIFLE criteria, but no patient had a change consistent with “Injury”, “Failure” or “Loss” of renal function and none had clinical signs of new acute renal impairment post-operatively. Conclusions. The implantation of up to 525mg of gentamicin contained within Cerament G, as part of the surgical treatment of osteomyelitis, is safe and carries minimal risk of significant acute kidney injury. A small, transient increase in serum creatinine may be observed in the early post-operative period, and attention should be paid to limit patients exposure to other nephrotoxic agents. The majority of patients will return to their baseline renal function within 7 days following the operation. The presence of pre-existing renal disease is not a contraindication to local gentamicin therapy

Prosthetic joint infections (PJI) are devastating complications. Our knowledge on hip fractureassociated hemiarthroplasty PJI (HHA-PJI) is limited compared to elective arthroplasty. The goal of this study was to describe the epidemiology, risk factors, management, and outcomes for HHA-PJI. A population-based (465,000) multicentre retrospective analysis of HHAs between 2006-2018 was conducted. PJI was defined by international consensus and treatment success as no return to theatre and survival to 90 days after the initial surgical management of the infection. Univariate, survival and competing risk regression analyses were performed. 1852 HHAs were identified (74% female; age:84±7yrs;90-day-mortality:16.7%). Forty-three (2.3%) patients developed PJI [77±10yrs; 56% female; 90-day-mortality: 20.9%, Hazard-Ratio 1.6 95%CI 1.1-2.3,p=0.023]. The incidence of HHA-PJI was 0.77/100,000/year and 193/100,000/year for HHA. The median time to PJI was 26 (IQR 20-97) days with 53% polymicrobial growth and 41% multi-drug resistant organisms (MDRO). Competing risk regression identified younger age [Sub-Hazard-Ratio(SHR) 0.86, 95%CI 0.8-0.92,p<0.001], chronic kidney disease (SHR 3.41 95%CI 1.36-8.56, p=0.01), body mass index>35 (SHR 6.81, 95%CI 2.25-20.65, p<0.001), urinary tract infection (SHR 1.89, 95%CI 1.02-3.5, p=0.04) and dementia (SHR 9.4, 95%CI 2.89-30.58,p<0.001) as significant risk factors for developing HHA-PJI. When infection treatment was successful (n=15, 38%), median survival was 1632 days (IQR 829-2084), as opposed to 215 days (IQR 20-1245) in those who failed, with a 90-day mortality of 30%(n=12). There was no significant difference in success among debridement, excision arthroplasty or revision arthroplasty. HHA PJI is uncommon but highly lethal. All currently identified predictors are non-modifiable. Due to the common polymicrobial and MDRO infections our standard antibiotic prophylaxis may not be adequate HHA-PJI is a different disease compared to elective PJI with distinct epidemiology, pathogens, risk factors and outcomes, which require targeted research specific to this unique population

Aim. Prosthetic joint infection (PJI) is a devastating and costly complication of total joint arthroplasty (TJA). Use of extended oral antibiotic prophylaxis (EOAP) has become increasingly popular in the United States following a highly publicized study (Inabathula et al) from a single center demonstrating a significant protective effect (81% reduction) against PJI in ‘high-risk’ patients. However, these results have not been reproduced elsewhere and EOAP use directly conflicts with current antibiotic stewardship efforts. In order to study the role of EOAP in PJI prevention, consensus is needed for what defines ‘high-risk’ patients. The revision TJA (rTJA) population is an appropriate group to study due to having a higher incidence of PJI. The purpose of the current study was to rigorously determine which preoperative conditions described by Inabathula et al. (referred to as Inabathula criteria (IBC)) confer a higher rate of PJI in patients undergoing aseptic rTJA. Method. 2,256 patients that underwent aseptic rTJA at a single high-volume institution between 2016–2022 were retrospectively reviewed. Patient demographics and comorbidities were recorded to determine if they had 1 or more ‘IBC’, a long list of preoperative conditions including autoimmune diseases, active smoking, body mass index (BMI)>35, diabetes mellitus, and chronic kidney disease (CKD). Reoperation for PJI at 90-days and 1-year was recorded. Chi-squared or Fischer's exact tests were calculated to determine the association between preoperative presence/absence of IBC and PJI. Multivariable logistic regressions were conducted to determine if specific comorbidities within the IBC individually conferred an increased PJI risk. Results. 1223 patients (54.2%) had at least one IBC condition. IBC-positive patients were more likely to be female, have an increased ASA score, and higher BMI. IBC-positive patients had a significant increase in PJI risk at both 90-days (relative risk (RR)=2.32, p<0.0001) and 1-year (RR=2.14, p=0.002) versus IBC-negative patients. Within IBC-positive patients, every additional IBC condition conferred a 1.8× odds increase for 90-day PJI (p<0.0001), and 1.76× odds increase in 1-year PJI (p<0.0001). Multivariable logistic regression identified active smoking, BMI>35, CKD, and diabetes mellitus as being independently associated with PJI development (p<0.05). Conclusions. Over half of rTJA patients meet IBC and could be eligible to receive EOAP in the United States. However, the specific presence of active smoking, BMI>35, CKD, and diabetes mellitus appear to be responsible for the increased risk of PJI. Prospective studies investigating EOAP use for patients with these specific conditions are urgently needed to prevent unnecessary antibiotic use

Aim. Sepsis is a life-threatening complication of periprosthetic joint infections (PJI) that requires early and effective therapy. This study aims to investigate the epidemiology, associated risk factors, and outcome of sepsis in the context of periprosthetic joint infections (PJI). Method. This single-center retrospective cohort study included patients treated for PJI from 2017 to 2020. Patients were classified based on the criteria of the European Bone and Joint Infection Society. The presence of sepsis was determined using the SOFA score and SIRS criteria. The cohort with PJI and sepsis (sepsis) was compared to patients with PJI without sepsis (non-sepsis). Risk factors considered were patient characteristics, affected joints, surgical therapy, microbiological findings, preexisting medical conditions, clinical symptoms, and symptom duration. Outcome parameters were mortality, length of hospital stay, and length of stay in the intensive care unit. Results. A total of 109 patients with PJI were identified, of whom 45 patients (41.3%) met the criteria for sepsis. Patients with sepsis had more severe preexisting diseases compared with the non-sepsis cohort (Charlson Comorbidity Index 3.8 vs. 2.8; p≤0.001). An increased odds ratio (OR) for a septic course was found for the comorbidities pneumonia (8.2; p=0.001), myocardial infarction (2.0; p=0.02), atrial fibrillation (3.3; p=0.01), diabetes mellitus (1.2; p=0.04), endocarditis (5.5; p=0.01), and renal disease (2.0; p≤0.001). Infection with Staphylococcus aureus (sepsis 20 vs. non-sepsis 10; p=0.002), Streptococcus dysgalactiae (sepsis 7 vs. non-sepsis 2; p=0.002) and Candida albicans (sepsis 5 vs. non-sepsis 0; p=0.01) were more prevalent in patients with sepsis. In the sepsis cohort, further infectious foci were present in addition to PJI in 57.8% of patients, compared to 18.8% in the non-sepsis cohort. The presence of sepsis was associated with a longer hospital stay (sepsis 68 days vs. non-sepsis 38 days; p=0.001) and longer intensive care unit stay (sepsis 12 days vs. non-sepsis 2 days; p=0.001). In-hospital mortality was ten times higher in the sepsis cohort compared to non-septic patients (sepsis 11/42 vs. non-sepsis 2/64; OR 10.3; p=0.01). Conclusions. In a relevant proportion of patients, PJI can lead to a septic course of disease associated with increased mortality. Particularly in patients with preexisting diseases, increased attention is required, and comprehensive screening for other foci of infection seems mandatory. In addition to highly virulent pathogens such as staphylococci and streptococci, fungal infections should be considered as causative pathogens in septic patients with PJI

Diabetes mellitus is a risk factor for complications after operative management of ankle fractures. Generally, diabetic sequelae such as neuropathy and nephropathy portend greater risk; however, the degree of risk resulting from these patient factors is poorly defined. We sought to evaluate the effects of the diabetic sequelae of neuropathy, chronic kidney disease (CKD), and peripheral vascular disease (PVD) on the risk of complications following operative management of ankle fractures. Using a national claims-based database we analyzed patients who had undergone operative management of an ankle fracture and who remained active in the database for at least two years thereafter. Patients were divided into two cohorts, those with a diagnosis of diabetes and those without. Each cohort was further stratified into five groups: neuropathy, CKD, PVD, multiple sequelae, and no sequelae. The multiple sequelae group included patients with more than one of the three sequelae of interest: CKD, PVD and neuropathy. Postoperative complications were queried for two years following surgery. The main complications of interested were: deep vein thrombosis (DVT), surgical site infection, hospital readmission within 90 days, revision internal fixation, conversion to ankle fusion, and below knee amputation (BKA). We identified 210,069 patients who underwent operative ankle fracture treatment; 174,803 had no history of diabetes, and 35,266 were diabetic. The diabetic cohort was subdivided as follows: 7,506 without identified sequelae, 8,994 neuropathy, 4,961 CKD, 1,498 PVD, and 12,307 with multiple sequelae. Compared to non-diabetics, diabetics without sequelae had significantly higher odds of DVT, infection, readmission, revision internal fixation and conversion to ankle fusion (OR range 1.21 – 1.58, p values range Compared to uncomplicated diabetics, diabetics with neuropathy alone and diabetics with multiple sequelae were found to have significantly higher odds of all complications (OR range 1.18 – 31.94, p values range < 0.001 - 0.034). Diabetics with CKD were found to have significantly higher odds of DVT, readmission, and BKA (OR range 1.34 – 4.28, p values range < 0.001 - 0.002). Finally, diabetics with PVD were found to have significantly higher odds of DVT, readmission, conversion to ankle fusion, and BKA (OR range 1.62 - 9.69, p values range < 0.001 - 0.039). Diabetic patients with sequelae of neuropathy, CKD or PVD generally had higher complication rates than diabetic patients without these diagnoses. Unsurprisingly, diabetic patients with multiple sequalae are at the highest risk of complications and had the highest odds ratios of all complications. While neuropathy is known to be associated with postoperative complications, our analysis demonstrates that CKD represents a significant risk factor for multiple complications following the operative management of ankle fractures and has rarely been discussed in prior studies

Aim. Knee arthrodesis (KA) and above knee amputation (AKA) have been used for salvage of failed total knee arthroplasty (TKA) in the setting of periprosthetic joint infection (PJI). The factors that lead to a failed fusion and progression to AKA are not well understood. The purpose of our study was to determine factors associated with failure of a staged fusion for PJI and predictive of progression to AKA. Method. We retrospectively reviewed a single-surgeon series of failed TKA for PJI treated with two-stage KA between 2000 and 2016 with minimum 2-year follow-up. Patient demographics, comorbidities, surgical history, tissue compromise, and radiographic data were recorded. Outcomes were additional surgery, delayed union, Visual Analog Pain scale (VAS) and Western Ontario and McMaster Activity score (WOMAC). No power analysis was performed for this retrospective study. Medians are reported as data were not normally distributed. Results. Fifty-one knees underwent fusion with median follow-up of 7 years (interquartile range (IQR) of 2–18 years). Median age was 71 years old (IQR 47 – 98), with a M:F ratio of 23:28. Median BMI was 34.3 kg/m2 (IQR 17.9–61). Infection was eradicated in 47 knees (92.2%); 24 knees (47.0%) required no additional surgery. 41 patients (83.6%) remained ambulatory after knee fusion, with 21% of these patients (10 total) requiring no ambulatory assistive device. Median VAS following arthrodesis was 4.6 (range 0–10). Median WOMAC was 36.2 (range 9–86). Three TKAs (5.9%) underwent AKA for overwhelming infection. Predictors of AKA were chronic kidney disease (OR 4.0, 95% CI 0.6–26.8), peripheral vascular disease (OR 3.5, 95% CI 0.3–44.7), AORI III bone loss (OR 2.6, 95% CI 0.4–35.2), instability (OR 2.2, 95% CI 0.2–15.9), and immunosuppression (OR 1.1, 95% CI 0.1–7.8). Tobacco use (OR 8.6, 95%CI 2.4–31.4), BMI>25 (OR 3.8, 95% CI 0.43–32.5) and instability prior to arthrodesis (OR 2.51, 95% CI 0.77–8.21) were associated with non-union. All other risk factors (gender, diabetes mellitus, chronic kidney disease, peripheral vascular disease, massive bone stock loss, and immunosuppression) were not associated with arthrodesis failure. Conclusions. Staged KA for PJI in severely compromised hosts provides a functional limb free of infection and rarely results in conversion to AKA. Given our small sample size, ability to establish statistical significance of predictive factors for AKA after PJI was limited, but CKD, peripheral vascular disease, AORI III bone loss, instability, and immunosuppression trended towards significance as predictors of failure of KA after PJI predisposing to AKA

Aim. To investigate self-reported quality of life (QoL) in patients with osteomyelitis referred to a specialist centre in the UK and investigate the relationship between QoL and BACH classification. Method. All patients newly referred to a specialist bone infection clinic at a single tertiary centre within the UK between January 2019 and February 2020 were prospectively included. Diagnosis of osteomyelitis was made according to the presence of clinical and radiological criteria for ≥6 months. An EQ-5D-5L questionnaire and visual analogue score (VAS) were completed during the initial clinic appointment. Long-bone osteomyelitis was classified by the attending orthopaedic surgeon using the BACH classification system as either uncomplicated, complex or with limited options available.1 Patients managed non-operatively were subclassified into those who were (i) unfit to receive an operation or (ii) fit and well with stable disease. EQ-5D index scores were compared to a published UK value set of 41 chronic health conditions within the UK.2. Results. 201 patients were referred during the study period, with 159 (79.1%) patients diagnosed with long-bone osteomyelitis and 16 (8.0%) with osteomyelitis of the pelvic bones. Patients with pelvic osteomyelitis reported lower EQ-5D index scores compared to long-bone osteomyelitis (EQ-5D: 0.097 vs. 0.435, p<0.001) but similar VAS (60.2 vs. 54.6, p=0.37). Long-bone and pelvic osteomyelitis gave the 40th and 41st lowest EQ-5D scores respectively when compared to 41 other chronic health conditions including stroke, chronic obstructive pulmonary disease, kidney disease, liver disease and malignancy. Patients classified as having uncomplicated long-bone osteomyelitis reported significantly higher QoL compared to those classified as complex osteomyelitis (EQ-5D: 0.527 vs. 0.401, p<0.05; VAS: 66.9 vs. 58.4, p<0.05). Patients who were not fit for surgery due to co-morbidity reported similar QoL scores compared to those patients with complex osteomyelitis (EQ-5D: 0.293, p=0.07; VAS: 46.6, p=0.06). Patients with stable disease who did not require surgery, gave significantly better QoL scores when compared to the other classifications of osteomyelitis (EQ-5D: 0.746, p<0.01; VAS: 81.9, p<0.01). Conclusions. Patient reported QoL in osteomyelitis correlates with disease complexity as classified according to the BACH classification system. Patients with pelvic and long-bone osteomyelitis rate their QoL lower than patients with other chronic diseases

Introduction. Total joint arthroplasty is associated with substantial blood loss as well as changes in basic metabolic labs. Routinely patients receive multiple post-operative blood draws for measuring hematocrit, hemoglobin (H&H), and basic metabolic panels (BMP). Based on a multimodal approach to blood conservation and pre-operative optimization, we questioned the need to check daily labs on our inpatient primary total hip and knee patients. The purpose of this study was to identify risk factors for transfusion and metabolic abnormalities requiring treatment in an attempt to reduce the number of post-operative blood draws and labs. Methods. We retrospectively reviewed all 1134 patients who underwent primary total hip (THA) or total knee arthroplasty (TKA) from July 2016 to March 2017 in our inpatient hospital setting. There were 733 TKA and 401 THA. Pre- and post-operative lab values were reviewed and correlated with transfusion and medical treatments. Results. Twelve patients received a post-operative transfusion (1.1%). In TKA patients 2 of 733 (0.2%) were transfused while in THA patients 10 of 401 (2.4%) were transfused. Of the 12 patients receiving transfusions 11 were females, and in all 12 the pre-operative hemoglobin was less than 13. For the overall series of 1134 patients, 176 (15.5%) required potassium chloride supplementation based on BMP. Only patients with pre-existing renal disease or diuretic treatment received potassium chloride supplementation. Conclusions. Based on our findings, only patients with pre-operative hemoglobin less than 13 require post-operative H&H. Additionally, only patients with low pre-operative potassium, history of renal disease, or active treatment with a diuretic require post-operative BMP

Introduction. This study assesses self-reported quality of life (QoL) in patients with osteomyelitis referred to a specialist centre in the UK. Materials and Methods. All patients newly referred to a specialist tertiary bone infection clinic within the UK between January 2019 and February 2020 were prospectively included. Diagnosis of osteomyelitis was made according to the presence of clinical and radiological criteria for ≥6 months. An EQ-5D-5L questionnaire and visual analogue score (VAS) were completed during the initial clinic appointment. Long-bone osteomyelitis was classified by the attending orthopaedic surgeon using the BACH classification system as either uncomplicated, complex or with limited options available. Patients managed non-operatively were subclassified into those who were (i) unfit to receive an operation or (ii) fit and well with stable disease. EQ-5D index scores were compared to a published UK value-set of 41 chronic health conditions within the UK. Results. 201 new patients were referred during the study period. 159 (79.1%) met the criteria for long-bone osteomyelitis and 16 (8.0%) for osteomyelitis of the pelvic bones. Patients with pelvic osteomyelitis reported lower EQ-5D index scores compared to long-bone osteomyelitis (EQ-5D:0.097 vs. 0.435, p<0.001) but similar VAS (60.2 vs. 54.6, p=0.37). Long-bone and pelvic osteomyelitis gave the lowest EQ-5D scores respectively when compared to 41 other chronic health conditions including stroke, chronic obstructive pulmonary disease, kidney disease, liver disease and malignancy. Patients classified as having uncomplicated long-bone osteomyelitis reported significantly higher QoL compared to those classified as complex osteomyelitis (EQ-5D:0.527 vs. 0.401, p<0.05; VAS: 66.9 vs. 58.4, p<0.05). Patients not fit for surgery due to co-morbidity reported similar QoL scores compared to those patients with complex osteomyelitis (EQ-5D: 0.293, p=0.07; VAS: 46.6, p=0.06). Patients with stable disease who did not require surgery, gave significantly better QoL scores when compared to the other classifications of osteomyelitis (EQ-5D: 0.746, p<0.01; VAS: 81.9, p<0.01). Conclusions. Patient reported QoL in osteomyelitis correlates with disease complexity as classified according to the BACH classification system. Patients with pelvic and long-bone osteomyelitis rate their QoL lower than patients with other major chronic diseases

Currently 180 days is the target maximum wait time set by all Canadian provinces for elective joint replacement surgery. In Nova Scotia however, only 34% of Total Knee Arthroplasties (TKA) and 51% of Total Hip Arthroplasties (THA) met this benchmark in 2017. Surgery performed later in the natural history of disease is shown to have significant impact on pain, function and Health related Quality of Life at the time of surgery and potentially affect post-operative outcomes. The aim of this study is to describe the association between wait time and acute hospital Length of Stay (LOS) during elective hip and knee arthroplasty in province of Nova Scotia. Secondarily we aim to describe risk factors associated with variations in LOS. Data from Patient Access Registry Nova Scotia (PAR-NS) was linked to the hospital Discharge Access Database (DAD) for primary hip and knee arthroplasty spanning 2009 to 2017. There were 23,727 DAD observations and 21,329 PARNS observations identified. Observations were excluded based on missing variables, missing linkages, revision status and emergency cases. Percentage difference in LOS, risk factors and outcomes were analyzed using Poisson regression for those waiting more than 180 days compared to those waiting equal or less than 180 days. For primary TKA, 11,833 observations were identified with mean age of 66 years, mean wait time of 348 days and mean LOS of 3.6 days. After adjusting for controls, patients waiting more than 180 days for elective TKA have a 2.5% longer acute care LOS (p < 0.028). Risk factors identified for prolonged LOS are advanced age, female gender, higher surgical priority indicator, required blood transfusion, dementia, peptic ulcer disease, cerebrovascular disease, heart failure, chronic kidney disease, malignancy, ischemic heart disease and diabetes. Factors associated with decreased LOS are surgical year, use of local anesthetic, peripheral location of hospital and admission to hospital from home. For primary THA, 6626 observations were identified with mean age of 66 years, mean wait time of 267 days and mean LOS of 4 days. Patients waiting more than 180 days for THA did not show a statistically significant association with LOS. Risk factors and protective factors are the same with exception of CVD and use of local anesthetic. Our findings suggest a positive and statistically significant association for patients waiting more than 180 days for TKA and longer acute care LOS. Longer LOS may be due to deteriorating health status while placed on a surgical waitlist and may represent a delayed and indirect cost to the patient and the healthcare system. Ultimately with projected increase in demand for elective joint replacement surgeries, our findings are aimed to inform physicians and policy makers in management of surgical waitlist efficiency and cost effectiveness. For any reader inquiries, please contact . shahriar-s@hotmail.com

The clinical guidelines for hip fracture management indicate that indwelling foley catheterization should be avoided when possible. Alternatives to indwelling catheters such as intermittent or condom catheters are recommended. Appropriate catheterization usage is important in hip fracture patients to avoid complications such as urinary tract infections (UTIs) (7–24% of patients) or post-operative urinary retention (POUR) (20–56% of patients). In this study, we aim to, (1) evaluate catheter usage in hip fracture patients at a large tertiary care centre, (2) compare current practices in catheter usage to clinical guidelines, (3) determine the incidence of POUR in hip fracture patients (4) determine the factors that increase one's risk of developing POUR. We analyzed 584 hip fracture patients between the ages of 18 and 102 admitted between November 2015 and October 2017 at a tertiary Care Hospital. Data collected included patient demographics, fracture pattern, surgical procedure, length of stay, co-morbidities and catheter use. We compared actual catheter usage to suggested guidelines to determine whether recommendations were being followed. We also investigated the incidence of POUR and risk factors associated with developing POUR. Independent samples t-test were used to compare continuous dependent variables in bivariate analyses and a logistic regression was used to determine predictors of developing POUR, catheter usage, and length of stay in multivariate analyses. T. Over three quarters (76.9%) of patients with hip fractures were treated with a catheter during their admission, 63.5% of which were inserted pre-operatively and 36.5% of which were inserted post-operatively. Indwelling catheters accounted for 92.2% of catheters used, while intermittent and catheter condoms accounted for 7.8%. POUR occurred in 98 of 584 cases (16.7%). Age (p = 0.004), gender (p=0.001), and presence of kidney disease (p=0.033) were statistically significant predictors of POUR. Fracture pattern (p=0.825), surgical procedure (p=0.298), diabetes mellitus (p=0.309) and UTI in the past 60 days (p=0.848) or on admission (p=0.999) were not statistically significant predictors of developing POUR. The development of POUR did not significantly increase length of stay (p=0.558). There was no statistically significant correlation between developing POUR and extended post-operative catheter use over 24 hours (p=0.844) or 48 hours (p=0.862). Patients who received a catheter pre-operatively or post-operatively for longer than 24 hours were not significantly more likely to develop POUR (p=0.057). Catheter use was common for all hip fracture patients and indwelling catheters were used in the overwhelming majority of cases. The high frequency of catheter usage, and specifically indwelling catheter usage, suggests that there is low compliance with the clinical guidelines for hip fracture patients. The incidence of POUR was 17%. Older, male patients were more likely to develop POUR. Although not statistically significant, more appropriate catheter use may decrease urinary complications such as POUR

Up to 40% of patients are using opioids at the time of joint replacement surgery in the USA despite emerging evidence suggesting opioids are ineffective for chronic non-cancer pain. Our primary objective was to determine if preoperative opioid use among patient awaiting total knee arthroplasty (TKA) was associated with worse patient-reported outcomes (PRO) measures at one-year follow-up when compared to non-opioid users, after adjusting for age, gender, and comorbidities. The study linked Alberta's Pharmacy Information Network (PIN) data with prospectively collected Alberta Bone and Joint Health Repository administrative data (medical and PRO data) for patients who underwent primary TKA in Alberta from 2013–2015. The PIN contains prescribing information from physician offices and pharmacies across Alberta. Preoperative ‘opioid users’ were defined as having 90-days of consistent opioid use in the 180-days prior TKA, and ‘opioid-exposed’ subjects had recorded opioid prescriptions in the 180-days prior to TKA, but did not meet the definition of an opioid user. Those with no opioid-exposure in the 180-days pre-TKA were deemed a ‘non-opioid user’. We used multiple linear regression to examine how preoperative opioid use (opioid user, opioid-exposed, non-opioid user) impacted Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores at one year after TKA after adjusting for confounding variables. These included age, sex, preoperative WOMAC scores, comorbidities including depression, diabetes, obesity, stroke, pulmonary disease, renal disease, cardiac disease, liver disease, and overall comorbid burden. Of the 2182 unique cases identified, 151 (7%) were opioid users, 527 (24%) opioid-exposed and 1504 (69%) non-opioid user. Opioid users were more likely to be prescribed strong opioids (e.g., hydromorphone, oxycodone) compared to with opioid-exposed subjects (p < 0 .001) and had a median morphine equivalent dose of 30.7 mg/day compared with the opioid-exposed group (2.2 mg/day, p < 0 .001) in the 180-days prior to TKA. Opioid users, in the 180-days prior to TKA had an active opioid prescription for a mean duration of 153 days (95CI 149, 157) within the 180-days prior to TKA, compared to 34 days (95CI 32, 37) for opioid-exposed (p < 0 .001). In the parsimonious pain and function models, opioid use, lower preoperative WOMAC score, depression, and obesity were associated with worse one-year pain and function. Patients prescribed preoperative opioids had worse WOMAC scores one-year after TKA respectively when compared to non-opioid users, after adjusting for other factors (opioid user pain score: −9.5, function score: −9.4, opioid exposed pain score: −2.6, function score: −3.6, p < 0 .001 for all). Further, opioid users with a concomitant diagnosis of depression had significantly worse one-year postoperative WOMAC scores when compared to non-depressed non-opioid users (scores −14, p < 0 .001 for both pain and function). In Alberta, 31% of patients were prescribed opioids within 180-days before TKA, preoperative opioid use was associated with worse one-year postoperative WOMAC pain and function scores relative to non-opioid users. Our results suggest that strategies to reduce preoperative opioid use could improve patient outcomes after TKA, and support the most recent Canadian opioid prescribing guidelines that attempt to minimize opioid use for chronic conditions such as arthritis

Up to 40% of patients are using opioids at the time of joint replacement surgery in the USA despite emerging evidence suggesting opioids are ineffective for chronic non-cancer pain. Our primary objective was to determine if preoperative opioid use among patient awaiting total knee arthroplasty (TKA) was associated with worse patient-reported outcomes (PRO) measures at one-year follow-up when compared to non-opioid users, after adjusting for age, gender, and comorbidities. The study linked Alberta's Pharmacy Information Network (PIN) data with prospectively collected Alberta Bone and Joint Health Repository administrative data (medical and PRO data) for patients who underwent primary TKA in Alberta from 2013–2015. The PIN contains prescribing information from physician offices and pharmacies across Alberta. Preoperative ‘opioid users’ were defined as having 90-days of consistent opioid use in the 180-days prior TKA, and ‘opioid-exposed’ subjects had recorded opioid prescriptions in the 180-days prior to TKA, but did not meet the definition of an opioid user. Those with no opioid-exposure in the 180-days pre-TKA were deemed a ‘non-opioid user’. We used multiple linear regression to examine how preoperative opioid use (opioid user, opioid-exposed, non-opioid user) impacted Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores at one year after TKA after adjusting for confounding variables. These included age, sex, preoperative WOMAC scores, comorbidities including depression, diabetes, obesity, stroke, pulmonary disease, renal disease, cardiac disease, liver disease, and overall comorbid burden. Of the 2182 unique cases identified, 151 (7%) were opioid users, 527 (24%) opioid-exposed and 1504 (69%) non-opioid user. Opioid users were more likely to be prescribed strong opioids (e.g., hydromorphone, oxycodone) compared to with opioid-exposed subjects (p < 0 .001) and had a median morphine equivalent dose of 30.7 mg/day compared with the opioid-exposed group (2.2 mg/day, p < 0 .001) in the 180-days prior to TKA. Opioid users, in the 180-days prior to TKA had an active opioid prescription for a mean duration of 153 days (95CI 149, 157) within the 180-days prior to TKA, compared to 34 days (95CI 32, 37) for opioid-exposed (p < 0 .001). In the parsimonious pain and function models, opioid use, lower preoperative WOMAC score, depression, and obesity were associated with worse one-year pain and function. Patients prescribed preoperative opioids had worse WOMAC scores one-year after TKA respectively when compared to non-opioid users, after adjusting for other factors (opioid user pain score: −9.5, function score: −9.4, opioid exposed pain score: −2.6, function score: −3.6, p < 0 .001 for all). Further, opioid users with a concomitant diagnosis of depression had significantly worse one-year postoperative WOMAC scores when compared to non-depressed non-opioid users (scores −14, p < 0 .001 for both pain and function). In Alberta, 31% of patients were prescribed opioids within 180-days before TKA, preoperative opioid use was associated with worse one-year postoperative WOMAC pain and function scores relative to non-opioid users. Our results suggest that strategies to reduce preoperative opioid use could improve patient outcomes after TKA, and support the most recent Canadian opioid prescribing guidelines that attempt to minimize opioid use for chronic conditions such as arthritis

Aim. To compare outcomes and incidence of adverse events (AE) of colistin versus tigecycline for treatment of patients with carbapenem-resistant Acinetobacter baumannii (CRAB) osteomyelitis. Method. Retrospective study. Records of 111 patients with microbiologically confirmed CRAB osteomyelitis were analyzed. Colistin (34 cases) and tigecycline (31 cases) were the main drugs used for treatment of extremely-drug resistant (XDR) isolates. Patients who received these two antimicrobials were compared according to baseline features (sex, age, length of hospital stay, Charlson index, presence of comorbidities or immunosuppression, previous renal disease, smoking, alcoholism or use of illicit drugs, previous orthopedic surgery on affected limb, topography of infection, classification of osteomyelitis, ASA score, infection related to pressure ulcer or neuropathic foot, presence of implant, need for soft tissue repair or negative pressure therapy and previous antimicrobial use), clinical outcome after 12 months of treatment (remission of infection was considered the favorable outcome; recurrence of infection, amputation and death were considered unfavorable outcomes; loss of follow-up was analyzed separately) and AE during treatment (impaired renal function; liver abnormalities; nausea; skin rash; neurological abnormalities and other events in general). Quantitative variables were described using summary measures and compared using Student's t or Mann-Whitney tests. Qualitative characteristics were described with absolute and relative frequencies and compared using chi-square or exact tests (Fisher's exact or likelihood ratio test). Results. Regarding baseline characteristics, proportion of male patients was higher in the group treated with colistin (p = 0.028). In the group treated with tigecycline, there was a significant predominance of smokers (p = 0.021) and patients with chronic osteomyelitis (p = 0.036). Regarding clinical outcomes after 12 months of treatment, there was no difference between groups. Overall incidence of AE was significantly higher among patients treated with colistin (p=0,047), as well as renal impairment (p = 0.003). Incidence of nausea was higher in patients treated with tigecycline (p = 0.046), but there was no difference between groups in relation to altered liver enzymes and other events. Conclusions. In this retrospective analysis, there was no significant difference between clinical outcomes of patients with CRAB osteomyelitis treated with colistin compared to tigecycline. Although the occurrence of nausea was greater in the group receiving tigecycline, this antimicrobial appeared to have a better safety profile for treatment of osteomyelitis related to XDR A. baumannii

Aim. The aim of this study was to compare outcomes between patients with diabetic foot soft-tissue infection and osteomyelitis. Methods. Medical records of patients with diabetic foot infection involving either soft-tissue (STI) or bone (OM) were retrospectively reviewed. Diagnosis was determined by bone culture, bone histopathology or imaging with magnetic resonance imaging (MRI) or single-photon emission computed tomography (SPECT/CT). Patient outcomes were recorded up to 1 year after admission. Results. Out of 294 patients included in the study, 137 were diagnosed with STI and 157 had OM. No differences in age (p=.40), sex (p=.79), race (p=.83), body-mass index (p=.79) or type of diabetes (p=.77) were appreciated between groups. Frequency of comorbidities (neuropathy, chronic kidney disease, peripheral arterial disease) also did not differ except for increased prevalence of cardiac disease in patients with STI (86.9%) compared to those with OM (31.8%) (p<.00001) and decreased prevalence of retinopathy (24.8% vs. 35.7%) (p=.04). Patients with OM had greater C-reactive protein (p<.00001), erythrocyte sedimentation rate (p<.00001) and white blood cell count (p<.00001). Among 1-year outcomes, patients with OM more often underwent surgery (p<.00001), had lower limb amputations (p<.00001), became reinfected (p=.0007), were readmitted for the initial problem (p=.008), had longer time to healing (p=.03) and had longer hospital length of stay (p=.00002). However, no differences in 1-year mortality (p=1.000), overall 1-year readmission (p=.06) or healing within 1-year (p=.64) were appreciated. Conclusion. In our study, OM was associated with more aggressive treatment, reinfection and longer time to healing than STI. However, despite being associated with more aggressive care and readmissions, patients with diabetic foot OM has similar 1-year mortality and healing rates to those with diabetic foot STI

Aim. Antibiotic-eluting calcium compounds can be used to deliver antibiotics in the management of prosthetic joint infection (PJI). Described omplications include wound drainage, heterotopic ossification(HO) as well as hypercalcaemia which is potentially life threatening. The aim of this study is to assess the incidence of hypercalcaemia and other complications between two calcium based antibiotic delivery systems. Method. A retrospective study was performed. Thirty two patients treated with Stimulan or Cerament Calcium based antibiotic delivery system between August 2014 to January 2017 were included. Seven patients received Cerament, 21 cases received Stimulan and one patient received both. The volume used as well as pre- and post-operative serum calcium were recorded as well as any wound related complications and radiologic changes suggestive of heterotopic ossification. The postoperative serum adjusted Calcium were taken weekly during the initial post operative period. Patients with overactive parathyroid disease and pre-existing renal disease were excluded. Results. Stimulan group (n=22, Mean volume 39.2ml). Mean pre-operative serum calcium was 2.48mmol/l. At 1 and 2 weeks post-surgery mean levels were 2.51 and 2.47mmol/l (patients receiving <40ml), and 2.47 and 2.50mmol/l (patients receiving >40ml – 9 cases) respectively. There was no significant difference between pre/post-operative levels at 1 (p=0.97) or 2 weeks (p=0.91) and no difference between those treated with <40ml or >40ml of Stimulan at 1 or 2 weeks (p=0.91). Cerament group (n=8, Mean volume 9.4ml). Mean pre-operative serum calcium was 2.42mmol/l. Mean post-operative levels at 1 and 2 weeks post-surgery were 2.44mmol/l (p=0.92) and 2.37mmol/l (p=0.61) respectively. One patient had prolonged wound discharge and required re operation. No HO was encountered. Conclusions. Our results suggest that hypercalcaemia and other complications are uncommon with the use calcium based antibiotic delivery systems and that calcium based antibiotic delivery systems are safe in the treatment of PJI

Aim. Following clean (class I, not contaminated) surgical procedures, the rate of surgical site infection (SSI) should be less than approximately 2%. However, an infection rate of 12.2% has been reported following removal of orthopedic implants used for treatment of fractures below the knee. The objective of this trial was to evaluate the effect of a single dose of preoperative antibiotic prophylaxis on the incidence of SSIs following removal of orthopedic implants used for treatment of fractures below the knee. Method. This multicenter, double-blind, randomized clinical trial included 500 patients from 19 hospitals with a follow-up of 6 months. Eligible were patients aged 18 to 75 years with previous surgical treatment for fractures below the knee who were undergoing removal of orthopedic implants. Exclusion criteria were an active infection or fistula, antibiotic treatment, reimplantation of osteosynthesis material in the same session, allergy for cephalosporins, known kidney disease, immunosuppressant use, or pregnancy. The intervention was a single preoperative intravenous dose of 1000 mg of cefazolin (cefazolin group, n = 228) or sodium chloride (0.9%; saline group, n = 242). Primary outcome was SSI within 30 days as measured by the criteria from the US Centers for Disease Control and Prevention. Secondary outcome measures were functional outcome, health-related quality of life, and patient satisfaction. Results. Among 477 randomized patients (mean age, 44 years [SD, 15]; women, 274 [57%]; median time from orthopedic implant placement, 11 months [interquartile range, 7–16]), 470 patients completed the study. Sixty-six patients developed an SSI (14.0%): 30 patients (13.2%) in the cefazolin group vs 36 in the saline group (14.9%) (absolute risk difference, −1.7 [95% CI, −8.0 to 4.6], P = .60). Conclusions. In patients undergoing surgery for removal of orthopedic implants used for treatment of fractures below the knee, a single preoperative dose of intravenous cefazolin compared with placebo did not reduce the risk of surgical site infection within 30 days following implant removal

Aim. Optimal strategies for surgical and antimicrobial management of Candida periprosthetic joint infections (PJI) are unclear. We present a retrospective case series of patients diagnosed with PJI caused by Candida spp. Method. Patients treated at our institution with Candida PJI from 01/2017 to 04/2018 were retrospectively included with isolation of Candida spp. in synovial fluid, intraoperative tissue or sonication fluid culture. PJI was defined by the proposed European Bone and Joint Infection Society (EBJIS) criteria. Treatment failure was defined as relapse or persistence of infection. Results. We included 9 patients (4 men and 5 women, mean age 75 years) involving 4 knee and 5 hip joint prosthesis. Risk factors for Candida PJI were prior PJI (n=4), diabetes mellitus (n=3), chronic kidney disease (n=3), obesity (n=3), negative-pressure wound therapy (n=3), rheumatoid arthritis (n=1) and chronic decubitus (n=1). Two patients had no risk factors for Candida PJI identified. Infection was acquired postoperatively (n=7), hematogenously (n=1) or contiguously through communicating vesico-articular sinus (n=1). The causative pathogen was C. albicans in 5, C. parapsilosis in 3, C. tropicalis in 1 patient, isolated from periprosthetic tissue samples (n=7), sonication fluid (n=3) and blood cultures (n=2); bacterial co-pathogens were isolated in 8 patients. Histopathological analysis revealed low-grade inflammation in all 6 patients, in whom it was performed. All patients were treated with oral fluconazole for 3 months, two initially received intravenous caspofungin and three received suppression with oral fluconazole for additional 9 months (total treatment 12 months). Liposomal amphotericin B (300–700 mg per 40 g bone cement) was admixed to spacer cement in 3 patients. Debridement and prosthesis retention was performed in one patient with tumor prosthesis after bone resection due to osteochondrosarcoma. In the remaining 8 patients the prosthesis was removed, with one-stage reimplantation in 1 patient and two-stage reimplantation in 3 patients (after 6 weeks, 3 months and 7 months); two patients are currently awaiting reimplantation, one died due to reason not related to PJI and another underwent knee arthrodesis. Among 5 patients with prosthesis in place, relapse occurred in one patient with prosthesis retention. Another patient experienced new PJI of the exchanged prosthesis caused by Staphylococcus aureus. Conclusions. All Candida PJI presented as chronic infection with low-grade inflammation. Treatment with prostheses retention failed, whereas in 4 patients who underwent two-stage exchange and long-term antifungal suppression, no relapse or persistence of infection was observed. All patients received oral fluconazole for ≥3 months