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.

Does Semaglutide Use Decrease Complications and Costs Following Total Knee Arthroplasty?

BACKGROUND: Diabetes mellitus (DM) and obesity are associated with total knee arthroplasty (TKA) complications. Semaglutide, a medication for DM and weight loss, can potentially affect TKA outcomes. This study investigated whether semaglutide use during TKA demonstrates fewer: (1) medical complications; (2) implant-related complications; (3) readmissions; and (4) costs. METHODS: A retrospective query was performed using a National database to 2021. Patients undergoing TKA for osteoarthritis with DM and semaglutide use were successfully propensity score-matched to controls semaglutide = 7,051; control = 34,524. Outcomes included 90-day postoperative medical complications, 2-year implant-related complications, 90-day readmissions, in-hospital lengths of stay, and costs. Multivariate logistical regressions calculated odds ratios (ORs), 95% confidence intervals, and P values (P < .003 as significance threshold after Bonferroni correction). RESULTS: Semaglutide cohorts had higher incidence and odds of myocardial infarction (1.0 versus 0.7%; OR 1.49; P = .003), acute kidney injury (4.9 versus 3.9%; OR 1.28; P < .001), pneumonia (2.8 versus 1.7%; OR 1.67; P < .001), and hypoglycemic events (1.9 versus 1.2%; OR 1.55; P < .001), but lower odds of sepsis (0 versus 0.4%; OR 0.23; P < .001). Semaglutide cohorts also had lower odds of prosthetic joint infections (2.1 versus 3.0%; OR 0.70; P < .001) and readmission (7.0 versus 9.4%; OR 0.71; P < .001), and trended toward lower odds of revisions (4.0 versus 4.5%; OR 0.86; P = .02) and 90-day costs ($15,291.66 versus $16,798.46; P = .012). CONCLUSION: Semaglutide use during TKA decreased risk for sepsis, prosthetic joint infections, and readmissions, but also increased risk for myocardial infarction, acute kidney injury, pneumonia, and hypoglycemic events.

The cost effectiveness of tranexamic acid for preventing periprosthetic joint infection following total shoulder arthroplasty: a break-even analysis.

BACKGROUND: The use of tranexamic acid (TXA) has become widespread in orthopedics to promote hemostasis and has been successfully used to reduce blood loss and infection risk in joint arthroplasty. However, the cost effectiveness of routine TXA use for the prevention of periprosthetic infections in total shoulder arthroplasty remains unknown. METHODS: The acquisition cost of TXA ($5.22) for our institution, along with values from the literature for the average cost of infection-related care ($55,243) and the baseline infection rates for patients without TXA use (0.70%),were used to perform a break-even analysis. The absolute risk reduction (ARR) of infection necessary to justify the prophylactic use of TXA in shoulder arthroplasty was calculated from the nontreated and break-even infection rates. RESULTS: TXA is considered cost-effective if it prevents one infection out of 10,583 total shoulder arthroplasty's (ARR = 0.009%). It is economically justifiable with an ARR range of 0.001% at a cost of $0.50/g to 0.181% at $100/g. At varying costs of infection-related care ($10,000-$100,000) and varying baseline infection rates (0.50%-8.00%) and routine use of TXA remained cost-effective. CONCLUSION: The use of TXA is an economically viable practice for infection prevention following shoulder arthroplasty if it reduces the infection rate by 0.009%. Future, prospective studies should be conducted to observe whether TXA reduces the infection rate by more than 0.009%, showing cost effectiveness.

Cost Drivers in Two-Stage Treatment of Hip Periprosthetic Joint Infection With an Antibiotic Coated Cement Hip Spacer.

BACKGROUND: The current gold standard for treating chronic Periprosthetic Joint Infection (PJI) is a 2-stage revision arthroplasty. There has been little investigation into what specific patient and operative factors may be able to predict higher costs of this treatment. METHODS: An institutional electronic health record database was retrospectively queried for patients who developed a PJI after a total hip arthroplasty, and underwent removal of the prosthesis and implantation of an antibiotic-impregnated articulating hip cement spacer. Patient demographics, surgical variables, hospital readmissions, emergency department visits, and post-operative complications were collected. Total costs were captured through an internal accounting database through 2 years post-operatively. Negative binomial regressions were utilized for multivariable analyses. A total of 55 hips with PJI were available for cost analyses. RESULTS: A comorbidity index score was associated with a 70% increase (Odds Ratio (OR): 1.7 [1.18-2.5], P = .003) in total costs at 2-years. Illicit drug use was associated with a 70% increase in costs at 1-year post-operatively (OR 1.7 [1.18-2.5], P = .003). Metal-on-poly liners were associated with a 22% decrease in cost at 2-years post-operatively when compared to Cement-on-Bone articulating spacers, and Metal-on-poly -constrained liners accounted for 38% lower costs at 1-year (OR 0.62 [0.44-0.87], P = .004). Use of an intraoperative extended trochanteric osteotomy was associated with a 46 and 61% increase in cost at 1-year (OR 1.46 [1.14-1.89]) and 2-years (OR 1.61 [1.26-2.07], P < .001) post-operatively. CONCLUSION: Age, comorbidity index score, drug use, and extended trochanteric osteotomy were associated with increased costs of PJI treatment. This may be used to improve reimbursement models and target areas of cost savings.

Manipulation Following Primary Total Knee Arthroplasty is Associated With Increased Rates of Infection and Revision.

BACKGROUND: Stiffness following total knee arthroplasty (TKA) is a disabling complication and manipulation under anesthesia (MUA) is often performed as an early intervention. Few studies have focused on the revision risk, infection risk, demographics, and clinical outcomes in Medicare patients undergoing MUA following primary TKA. METHODS: We reviewed 142,440 patients who had primary TKA from a national database and identified 3,652 patients (2.6%) who underwent MUA. Patient demographics and comorbid conditions were evaluated to identify risk factors. Incidence of revision and periprosthetic joint infection (PJI) at 1-, 2-, and 5-year time points in a cohort of MUA patients was compared to patients who did not undergo MUA. Multivariate Cox regressions were used for statistical analyses. RESULTS: The incidence of MUA was higher in Black versus White individuals (4.1 versus 2.5%, P < .001). Revision risk was significantly greater in the MUA group at 1-, 2-, and 5-year time points with a hazard ratio (HR) of, 3.81, 3.90, and 3.22 respectively, P < .001. One- and 2-year revision risk was significantly greater when MUA occurred at 6 to 12 months post-TKA when compared to <3 months, P < .05. Risk of PJI was significantly greater in the MUA group with a HR of 2.2, 2.2, and 2.1 at 1, 2, and 5 years, respectively P < .001. CONCLUSION: The incidence of MUA was 2.6%. There was an increased incidence of revision surgery and PJI in patients undergoing MUA. Patients at increased risk for stiffness following TKA should be closely monitored and treated with early intervention to minimize risk of poor outcomes.

The Cost-Effectiveness of Extended Oral Antibiotic Prophylaxis for Infection Prevention After Total Joint Arthroplasty in High-Risk Patients.

BACKGROUND: Extended oral antibiotic prophylaxis may decrease rates of prosthetic joint infection (PJI) after total joint arthroplasty (TJA) in patients at high risk for infection. However, the cost-effectiveness of this practice is not clear. In this study, we used a break-even economic model to determine the cost-effectiveness of routine extended oral antibiotic prophylaxis for PJI prevention in high-risk TJA patients. METHODS: Baseline PJI rates in high-risk patients, the cost of revision arthroplasty for PJI, and the costs of extended oral antibiotic prophylaxis regimens were obtained from the literature and institutional purchasing records. These variables were incorporated in a break-even economic model to calculate the absolute risk reduction (ARR) in infection rate necessary for extended oral antibiotic prophylaxis to be cost-effective. ARR was used to determine the number needed to treat (NNT). RESULTS: Extended oral antibiotic prophylaxis with Cefadroxil in patients at high risk for PJI was cost-effective at an ARR in baseline infection rate of 0.187% (NNT = 535) and 0.151% (NNT = 662) for TKA and THA, respectively. Cost-effectiveness was preserved with varying costs of antibiotic regimens, PJI treatment costs, and infection rates. CONCLUSION: The use of extended oral antibiotic prophylaxis may reduce PJI rates in patients at high risk for infection following TJA and appears to be cost-effective. However, the current evidence supporting this practice is limited in quality. The use of extended oral antibiotic prophylaxis should be weighed against the possible development of future antimicrobial resistance, which may change the value proposition.

Intra-Articular Corticosteroid or Hyaluronic Acid Injections Are Not Associated with Periprosthetic Joint Infection Risk following Total Knee Arthroplasty.

This study evaluated whether the preoperative use and timing of the use of hyaluronic acid (HA) and/or corticosteroid (CS) injections were associated with an increased risk of periprosthetic joint infections (PJIs) following primary total knee arthroplasty (TKA). We tested the hypothesis that preoperative injection of HA or CS within 3 months prior to primary TKA was associated with an increased risk of PJI by specifically evaluating the association between PJI risk and (1) injection type; (2) timing; (3) patient demographic factors; and (4) surgery-related factors, such as surgeon injection volume, knee arthroscopy (pre- and postoperative), and hospital length of stay. The 5% Medicare part B claims database was queried for patients who received CS and/or HA injections. Cox proportional hazards regressions evaluated the risk of PJIs after TKA, adjusting for patient and clinical factors, as well as propensity scores. The unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 0.89% for the HA group, 0.96% for both CS and HA group, and 0.75% for those who did not use HA or CS in the 12 months before TKA. For patients who used HA and/or CS within 3 months prior to TKA, the unadjusted incidence of PJI at 2-year post-TKA was 0.75% for the CS group, 1.07% for the HA group, and 1.00% for both CS and HA group, compared with 0.77% for those who did not use HA or CS. The number of injections performed per year was inconsistently associated with PJI risk. Overall, we found that intra-articular injections given within the 4-month period prior to TKA were not associated with elevated PJI risk (evaluated at 1, 3, 12, and 24 months after the index TKA) within the elderly Medicare patient population.

[Osteoarticular infections in patients with sickle cell disease in Lubumbashi: epidemiological study focusing on etiology and management]. / Les infections ostéo-articulaires chez les drépanocytaires à Lubumbashi: étude épidémiologique, étiologie et prise en charge.

INTRODUCTION: infections are the leading cause of morbidity and mortality in patients with sickle cell disease, especially before age 5 years. The purpose of this study was to highlight the epidemiological features, etiologies and management of osteoarticular infections in patients with sickle cell disease in Lubumbashi. METHODS: we conducted a descriptive, cross-sectional and retrospective study at the Research Center for Sickle Cell Disease in Lubumbashi (RCSCDL) over a three-year period from June 2014 to June 2017. It included all patients with sickle cell disease on follow up at the RCSCDL who developed osteoarticular infection. Data were obtained from a survey form. Parameters were patient's age, age at first visit, sex, reason for consultation, history, physical signs, diagnosis, paraclinical assessment and treatment. RESULTS: we identified 35 cases of osteoarticular infections out of a total of 380 cases of sickle-cell disease, reflecting a rate of 9.2%. The most affected age group was people under 5 years of age (37.1%); the average age was 10.9±9.5 years ranging from 8 months and 37 years. There was a slight female predominance (51.4% of cases; sex ratio 1.06 in favor of women). Most patients with osteoarticular infection had a history of transfusion (16.6%) and splenectomy (8.6%). The most common reason for consulting was limb pain (84%); 20 patients (57.1%) had bulbar conjunctival icterus and 26 (74.3%) were pale. Clinical examination showed limb swelling and wound in 27 patients (77.1%) and 19 patients (54.3%), respectively. Clinical palpation of the splenomegaly was performed in 6 patients (17.1%). Three types of osteoarticular infections were detected. They were dominated by osteomyelitis (24 cases; 68.57%) followed by osteitis (7 cases; 20%) and suppurative arthritis (4 cases; 11.43%). Out of 24 cases of osteomyelitis, 18 were acute (75%) and 6 were chronic (25%), of which 4 had a hyperostosing behaviour and 2 a fistulising behaviour. Tibia was the most affected bone (18 cases), X-ray mainly showed osteolysis (27 cases; 77.1%) and then periosteolysis (15 cases; 42.9%). Homozygous sickle cell disease was found in 88.6% of cases. Hemoculture was performed in 17 out the 35 patients and salmonella was isolated in 15 out of 17 cultures (88.23%). Pyoculture was performed in 10 patients; it isolated other germs. Assessment of inflammation was performed in 21 patients: 15 had hyperleukocytosis, 13 pathological white blood cell formula , all had increased sedimentation rate (greater than 20mm in the 1st hour). With respect to immunization schedule, 62.86% of patients received EPI vaccines while patients with sickle cell disease who needed specific vaccine had an adherence rate of 17.14%. With respect to therapy, all of our patients received medical treatment; 6 patients underwent sequestrectomy (17.14%) while the majority of patients (25 cases) underwent orthopedic treatment. Conclusion: bone infection in patients with sickle cell disease is a worryng issue in our poor environment where there isn't a specific vaccine for patients with sickle cell disease.

Revision knee replacement for prosthetic joint infection: Epidemiology, clinical outcomes and health-economic considerations.

Prosthetic joint infection (PJI) is a devastating complication of knee replacement surgery. Recent evidence has shown that the burden of disease is increasing as more and more knee replacement procedures are performed. The current incidence of revision total knee replacement (TKR) for PJI is estimated at 7.5 cases per 1000 primary joint replacement procedures at 10 years. Revision TKR for PJI is complex surgery, and is associated to a high rate of post-operative complications. The 5-year patient mortality is comparable to some common cancer diagnoses, and more than 15% of patients require re-revision by 10 years. Patient-reported outcome measures (PROMs) including joint function may be worse following revision TKR for PJI than for aseptic indications. The complexity and extended length of the treatment pathway for PJI places a significant burden on the healthcare system, highlighting it as an area for future research to identify the most clinically and cost-effective interventions.

In-Hospital Complications following Arthrotomy versus Arthroscopy for Septic Knee Arthritis: A Cohort-Matched Comparison.

There is a paucity of literature comparing the relative merits of open arthrotomy versus arthroscopy for the surgical treatment of septic knee arthritis. The primary goal of this study is to compare the risk of perioperative complications between these two surgical techniques. To this end, 560 patients treated for septic arthritis of the native knee with arthroscopy were statistically matched 1:1 with 560 patients treated with open arthrotomy. The outcome measures included major complications, minor complications, mortality, inpatient hospital charges, and length of stay (LOS). Major complications were defined as myocardial infarction, cardiac arrest, stroke, deep vein thrombosis, pulmonary embolism, pneumonia, postoperative shock, unplanned ventilation, deep surgical site infection, wound dehiscence, infected postoperative seroma, hospital acquired urinary tract infection, and retained surgical item. Minor complications included phlebitis and thrombophlebitis, postprocedural emphysema, minor surgical site infection, peripheral nerve complication, and intraoperative hemorrhage. Mortality data were extracted from the database using the Uniform Bill patient disposition. Complications were analyzed using univariate and multivariate logistic regression models, whereas mean costs and LOS were compared using the Kruskal-Wallis H-test. Major complications occurred in 3.8% of the patients in the arthroscopy cohort and 5.4% of the patients in the arthrotomy cohort (p = 0.20). Too few patients in our sample died to report based on National (Nationwide) Impatient Sample (NIS) minimum reporting standards. Rates of minor complications were similar for the arthroscopy and arthrotomy cohorts (12.5 vs. 13.9%; p = 0.48). Multivariate analysis did not reveal any greater risk of minor or major complication between the two procedures. Inpatient hospital cost was similar for arthroscopy ( = $15,917; standard deviation [SD] = 14,424) and arthrotomy ( = $16,020; SD = 18,665; p = 0.42). LOS was also similar for both arthrotomy (6.78 days, SD = 6.75) and arthroscopy (6.24 days, SD = 5.95; p = 0.23). Patients undergoing arthroscopic treatment of septic arthritis of the knee showed no difference in relative risk of perioperative complications, LOS, or hospital cost compared with patients who underwent open arthrotomy.

Hospital Stays and Medical Expenses Increase Nationwide Among Patients With Septic Arthritis of the Shoulder Who Inject Drugs.

The authors determined the proportion of patients nationwide with septic arthritis of the shoulder who inject drugs, evaluated differences in hospitalization outcomes and charges between patients with and without injection drug use (IDU), and quantified demographic trends among patients with IDU from 2000 to 2013. Nationally representative data of patients with a principal discharge diagnosis of shoulder septic arthritis were obtained from the Nationwide Inpatient Sample 2000-2013. Using published algorithms, the authors classified septic arthritis of the shoulder as related or unrelated to IDU. They compared length of stay, leaving against medical advice, number of procedures, and mortality rates between the 2 groups, using regression models to control for age, sex, and race. Fifteen percent (95% confidence interval [CI], 13.6%-16.5%) of septic arthritis cases were associated with IDU. From 2000 to 2013, shoulder septic arthritis associated with IDU increased 4-fold. After controlling for age, sex, and race, individuals who inject drugs stayed in the hospital for 3.7 more days (95% CI, 2.4-5.0), incurred an average of $13,250 more charges for medical care (95% CI, $2635-$23,866), and were 5.54 times more likely (95% CI, 3.22-9.55) to leave against medical advice than those without IDU. From 2000 to 2013, there was an increase in the proportion of patients with IDU-related septic arthritis of the shoulder between 35 and 54 years old and 55 and 64 years old, and an increase in the proportion who were white. Injection drug use-related shoulder septic arthritis is linked to suboptimal inpatient outcomes and greater resource use. [Orthopedics. 2020;43(4):e270-e277.].

Next-Generation Sequencing vs Culture-Based Methods for Diagnosing Periprosthetic Joint Infection After Total Knee Arthroplasty: A Cost-Effectiveness Analysis.

BACKGROUND: Periprosthetic joint infection (PJI) after total knee arthroplasty is challenging to diagnose. Compared with culture-based techniques, next-generation sequencing (NGS) is more sensitive for identifying organisms but is also less specific and more expensive. To date, there has been no study comparing the cost-effectiveness of these two methods to diagnose PJI after total knee arthroplasty. METHODS: A Markov, state-transition model projecting lifetime costs and quality-adjusted life years (QALYs) was constructed to determine the cost-effectiveness from a societal perspective. The primary outcome was incremental cost-effectiveness ratio, with a willingness-to-pay threshold of $100,000/QALY. Sensitivity analyses were performed to evaluate parameter assumptions. RESULTS: At our base case values, culture was not determined to be cost-effective compared to NGS, with an incremental cost-effectiveness ratio of $422,784 per QALY. One-way sensitivity analyses found NGS to be the cost-effective choice above a pretest probability of 45.5% for PJI. In addition, NGS was cost-effective if its sensitivity was greater than 70.0% and its specificity greater than 94.1%. Two-way sensitivity analyses revealed that the pretest probability and test performance parameters (sensitivity and specificity) were the largest factors for identifying whether a particular strategy was cost-effective. CONCLUSION: The results of our model suggest that the cost-effectiveness of NGS to diagnose PJI depends primarily on the pretest probability of PJI and the performance characteristics of the NGS technology. Our results are consistent with the idea that NGS should be reserved for clinical contexts with a high pretest probability of PJI. Further study is required to determine the indications and subgroups for which NGS offers clinical benefit.

Professional Athletes Are Not at a Higher Risk of Infections After Anterior Cruciate Ligament Reconstruction: Incidence of Septic Arthritis, Additional Costs, and Clinical Outcomes From the French Prospective Anterior Cruciate Ligament Study (FAST) Cohort.

BACKGROUND: The rate of septic arthritis in the knee after anterior cruciate ligament (ACL) reconstruction varies in the literature but is generally less than 1%. It has been reported to be higher in professional athletes (5.7%). PURPOSE: The primary goal was to evaluate the rate of septic arthritis after ACL reconstruction in professional athletes compared with other patients. The secondary goals were to analyze the risk factors; increased cost of infections; return to sport, satisfaction, and functional results at 1-year follow-up; and resolution rate of infections at final follow-up. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: This retrospective analysis of prospective data included a continuous series of patients who underwent isolated ACL reconstruction between 2012 and 2016. The main outcome criterion was the development of intra-articular infections in the operated knee. An infection was suggested clinically (knee pain with fever and/or chills) and confirmed bacteriologically in deep tissue samples obtained during revision surgery. All infected patients underwent an emergency reoperation with lavage and debridement along with dual antibiotic therapy first by an intravenous route and then orally for 6 weeks. RESULTS: A total of 1809 of 1859 patients included in the cohort during this period fulfilled inclusion criteria; there were 1632 (90.2%) who underwent primary reconstruction and 177 (9.8%) who underwent revision. The series included 1249 (69%) men and 560 (31%) women, with a mean age of 29.1 ± 9.8 years. Ninety-eight percent of the patients participated in a sport, including 90 (5.0%) at a professional level and 712 (39.4%) competitively. Septic arthritis of the knee developed after a mean 15.7 ± 5.5 days in 7 (0.38%) patients: 5 of 1632 (0.31%) who underwent primary reconstruction and 2 of 177 (1.13%) who underwent revision. Septic arthritis did not develop in any professional or competitive athletes; all affected patients were recreational athletes ( P = .02). The risk factors identified for the development of septic arthritis on multivariate analysis were prior knee surgery (odds ratio [OR], 15; P = .002) and hemarthrosis during the immediate postoperative period (OR, 127.2; P = .002). There were no recurrent infections after a mean follow-up of 2.8 ± 1.2 years. CONCLUSION: None of the professional athletes in this cohort had septic arthritis after ACL reconstruction. There are no particular precautions to be taken in this population. The risk factors identified for the development of septic arthritis on multivariate analysis were prior knee surgery and hemarthrosis during the immediate postoperative period. Similar to all studies published on the subject, there were very few infected patients, which limits the identification of risk factors. REGISTRATION: NCT02511158 (ClinicalTrials.gov identifier).

The Hidden Cost of Commercial Antibiotic-Loaded Bone Cement: A Systematic Review of Clinical Results and Cost Implications Following Total Knee Arthroplasty.

BACKGROUND: The purpose of this systematic review is to compare deep prosthetic joint infections (PJIs) between total knee arthroplasty (TKA) patients treated with either antibiotic-loaded bone cement (ALBC) or plain bone cement, and to explore the potential cost implications of commonly used bone cement regimens. We hypothesized that ALBC would not substantially reduce PJIs and would thereby present an unnecessary cost to the healthcare system. METHODS: Using the PRISMA guidelines, we reviewed articles through May 2017 involving primary TKA patients with both ALBC cohort and plain bone cement cohort. A meta-analysis was performed comparing the prevalence of deep infections between cohorts. A cost comparison for a hypothetical setting with an annual volume of 1000 TKAs was performed to compare 3 commonly used cement regimens: 2 bags of ALBC used during each case, 1 bag of ALBC with 1 bag of plain cement, and 2 bags of plain cement. Pricing at our institution is $215/bag for commercial ALBC and $60/bag for plain cement. RESULTS: Eight articles were included with a total of 34,664 patients. ALBC did not reduce the PJI (ALBC = 93/8189, 1.1% vs plain = 251/26,475, 0.9%; P = .09). The estimated costs for the 3 bone cement regimens per 1000 primary TKAs were as follows: 2 bags of ALBC = $430,000/y, 1 bag of ALBC +1 bag of plain cement = $275,000/y, and 2 bags of plain cement = $120,000/y. CONCLUSION: ALBC did not reduce the prevalence of PJI suggesting that ALBC may be an unnecessary cost to the healthcare system. Hospital systems that perform 1000 TKAs/y could save between $155,000 and $310,000/y by switching to plain cement.

Are We Winning or Losing the Battle With Periprosthetic Joint Infection: Trends in Periprosthetic Joint Infection and Mortality Risk for the Medicare Population.

BACKGROUND: Periprosthetic joint infection (PJI) is a potentially deadly complication of total joint arthroplasty. This study was designed to address how the incidence of PJI and outcome of treatment, including mortality, are changing in the population over time. METHODS: Primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients with PJI from the 100% Medicare inpatient data set (2005-2015) were identified. Cox proportional hazards regression models for risk of PJI after THA/TKA (accounting for competing risks) or risk of all-cause mortality after PJI were adjusted for patient and clinical factors, with year included as a covariate to test for time trends. RESULTS: The unadjusted 1-year and 5-year risk of PJI was 0.69% and 1.09% for THA and 0.74% and 1.38% for TKA, respectively. After adjustment, PJI risk did not change significantly by year for THA (P = .63) or TKA (P = .96). The unadjusted 1-year and 5-year overall survival after PJI diagnosis was 88.7% and 67.2% for THA and 91.7% and 71.7% for TKA, respectively. After adjustment, the risk of mortality after PJI decreased significantly by year for THA (hazard ratio = 0.97; P < .001) and TKA (hazard ratio = 0.97; P < .001). CONCLUSION: Despite recent clinical focus on preventing PJI, we are unable to detect substantial decline in the risk of PJI over time, although mortality after PJI has declined. Because PJI risk appears not to be changing over time, the incidence of PJI is anticipated to scale up proportionately with the demand for THA and TKA, which is projected to increase substantially in the coming decade.

Trends in Periprosthetic Hip Infection and Associated Costs: A Population-Based Study Assessing the Impact of Hospital Factors Using National Data.

BACKGROUND: Periprosthetic joint infection (PJI) is an important cost driver in hip arthroplasty revisions, thus necessitating careful trend monitoring. Recent national trend data are lacking; we therefore assessed national PJI burden, trends in prevalence, and hospitalization costs. METHODS: We extracted data on hip arthroplasty revisions from the National Inpatient Sample (2003-2013; n = 465,209). Trends in PJI prevalence and hospitalization costs were (1) assessed for the full cohort and (2) stratified by hospital teaching status, hospital bed size (≤299, 300-499, and ≥500 beds), and hospital region (Northeast, Midwest, South, and West). The Cochran-Armitage trend test (PJI prevalence) and linear regression (hospitalization costs) determined significance of trends. Trends were adjusted for patient's age, gender, insurance type, race, Deyo-Charlson comorbidities, obesity, length of stay, and hospital characteristics. RESULTS: Overall, PJI prevalence was 15.0% (n = 70,011); adjusted prevalence increased from 13.1% in 2003 to 16.4% in 2013 (P < .0001), while adjusted median PJI hospitalization costs increased from $28,240 in 2003 to $31,529 in 2013 (P < .0001). Rural hospitals had the lowest PJI burden (12.5%; n = 4,525), while urban and teaching hospitals had the highest PJI burden (16.4%; n = 40,297). The stratified analyses, particularly in large hospitals (>500 beds), showed that PJI prevalence increased from 13.0% (2003) to 17.4% (2013; a 33.8% increase; P < .0001). Similarly, PJI revision hospitalization costs increased from a median of $27,490 (2003) to $31,312 (2013; a 14% increase; P < .0001). CONCLUSION: The burden of PJI in hip arthroplasty revision is increasing and-while additional research is needed-there appears to be a particular shift of revision burden to larger hospitals with increasing costs.

Risk Factors for Repeat Debridement, Spacer Retention, Amputation, Arthrodesis, and Mortality After Removal of an Infected Total Knee Arthroplasty With Spacer Placement.

BACKGROUND: Chronic periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is most commonly addressed with a 2-stage exchange procedure. The purpose of this study is to examine the natural history of patients who have undergone prosthesis removal and spacer placement and evaluate risk factors for outcomes other than reimplantation. METHODS: Patients who underwent removal of an infected TKA and placement of an antibiotic spacer for PJI were identified in a Medicare database. Patients with a study outcome within 1 year were then identified: (1) in hospital mortality, (2) knee arthrodesis, (3) amputation, (4) repeat debridement procedure without reimplantation, and (5) reimplantation. Independent risk factors for these outcomes were evaluated with a multivariate logistic regression analysis. RESULTS: A total of 18,533 patients were included. Within 1 year postoperatively, 691 patients (3.7%) died in a hospital setting, 852 patients (4.5%) underwent a knee arthrodesis, 574 patients (3.1%) underwent an amputation, 2683 patients (14.5%) underwent a repeat debridement procedure without being reimplanted, 2323 patients (12.5%) retained their spacer, and 11,420 patients (61.6%) underwent spacer removal and reimplantation within 1 year. Numerous independent patient-related risk factors for these outcomes were identified. CONCLUSION: A large number of patients (38.4%) do not undergo reimplantation within 1 year of prosthesis removal and spacer placement. Outcomes after prosthesis removal and antibiotic spacer placement are variable, and there are several independent risk factors for such outcomes that may be used to develop and improve existing treatment strategies for patients presenting with chronic PJI after TKA.

Risk Factors and Costs Associated With Clostridium difficile Colitis in Patients With Prosthetic Joint Infection Undergoing Revision Total Hip Arthroplasty.

BACKGROUND: With the increased demand for primary total hip arthroplasty (THA) and corresponding rise in revision procedures, it is imperative to understand the factors contributing to the development of Clostridium difficile colitis. We aimed to provide a detailed analysis of: (1) the incidence of; (2) the demographics, lengths of stay, and total costs for; and (3) the risk factors and mortality associated with the development of C. difficile colitis after revision THA. METHODS: The National Inpatient Sample database was queried for all individuals diagnosed with a periprosthetic joint infection and who underwent all-component revision THA between 2009 and 2013 (n = 40,876). Patients who developed C. difficile colitis during their inpatient hospital stay were identified. Multilevel logistic regression analysis was conducted to assess the association between hospital- and patient-specific characteristics and the development of C. difficile colitis. RESULTS: The overall incidence of C. difficile colitis after revision THA was 1.7%. These patients were significantly older (74 vs 65 years), had greater lengths of hospital stay (19 vs 9 days), accumulated greater costs ($51,641 vs $28,282), and were more often treated in an urban hospital compared to their counterparts who did not develop C. difficile colitis (P < .001 for all). Patients with colitis also had a significantly higher in-hospital mortality compared to those without (5.6% vs 1.4%; P < .001). CONCLUSION: While C. difficile colitis infection is an uncommon event following revision THA, it can have potentially devastating consequences. Our analysis demonstrates that this infection is associated with a longer hospital stay, higher costs, and greater in-hospital mortality.

Anterior Cruciate Ligament Graft Removal Versus Retention in the Setting of Septic Arthritis After Reconstruction: A Systematic Review and Expected Value Decision Analysis.

PURPOSE: To provide further guidance on the optimal decision between anterior cruciate ligament (ACL) graft removal versus retention in the setting of septic arthritis following reconstruction using an expected value decision analysis. METHODS: A systematic review and expected value decision analysis and sensitivity analyses were performed to quantify the clinical decision. A decision tree was created with 5 outcomes of interest: nonoperative complications, revision surgery, early reoperation, late reoperation, and "well." Pooled probabilities of each outcome were generated through a systematic literature review. We included only peer-reviewed studies, published in English, with at least 6 months of follow-up. One hundred randomly selected volunteers were given descriptions of the clinical scenario, the 2 treatment options, and outcomes of interest. Patients younger than 18 and older than 50 years and those previously treated for either ACL injury or septic arthritis, or both, were excluded from the analysis to minimize bias. These hypothetical patients indicated preferences for each outcome on a visual analog scale and responses were averaged to generate overall "utility values." Fold-back analysis summed products of pooled outcomes probabilities with respective averaged utility values. The resulting overall expected values for graft removal and debridement were compared, with the highest expected value considered to be superior. We then performed 1-way sensitivity analyses to mitigate sample bias. RESULTS: Fold-back analysis revealed graft removal to be strongly favored over retention, with overall expected values of 17.2 and 8.64, respectively. The most important contributor to the difference in overall expected values was late reoperation (8.59 vs 2.50 for removal and retention, respectively). Despite adjustments made to the rates of revision and early reoperation during the 1-way sensitivity analyses, graft removal remained the optimal strategy. CONCLUSIONS: This expected value decision analysis revealed that ACL graft removal was strongly favored by patients over graft retention in the setting of postoperative septic arthritis when consideration was given to the probabilities of wellness, nonoperative complications, revision surgery, early reoperation, and late reoperation. Sensitivity analysis revealed that although variation in rates of other outcomes did not impact this preference, the rate of late reoperation had a substantial impact. Only a sizable increase in the probability of late reoperation (from 0% to 60%) after graft removal would cause potential patients to favor graft retention. LEVEL OF EVIDENCE: Level IV, systematic review and decision analysis.

Is There a Threshold Value of Hemoglobin A1c That Predicts Risk of Infection Following Primary Total Hip Arthroplasty?

BACKGROUND: There remains little evidence to support a perioperative hemoglobin A1c (HbA1c) level that could serve as a threshold for a significantly increased risk of deep postoperative infection in patients with diabetes mellitus (DM) following total hip arthroplasty (THA). METHODS: A national administrative database was queried for patients who underwent primary THA with DM. Patients with an HbA1c level within 3 months of surgery were identified and were stratified based on HbA1c level in 0.5 mg/dL increments. The incidence of deep infection requiring operative intervention within 1 year for each group was identified and a receiver operating characteristic (ROC) and area under the curve (AUC) analysis was performed to determine a threshold value of the HbA1c. RESULTS: A total of 7736 patients who underwent THA with a perioperative HbA1c level were included. The rate of infection ranged from 0.7% to 5.9%. The inflection point of the ROC curve corresponded to an HbA1c level between 7.0 and 7.5 mg/dL (P = .001, specificity = 69%, sensitivity = 47%). The AUC for the ROC was 0.68. Patients with an HbA1c level of 7.5 mg/dL or greater had a significantly higher risk of deep infection compared to patients below this threshold (odds ratio, 2.6; 95% CI, 1.9-3.4; P < .0001). CONCLUSION: The risk of infection in patients with DM increases as the perioperative HbA1c increases. However, in the present study, the HbA1c threshold level calculated demonstrated low discrimination based on our AUC value, suggesting the HbA1c test is poorly predictive of periprosthetic joint infection following THA in patients with DM.