Does Aseptic Revision Risk Differ for Primary Total Knee Arthroplasty Patients Who Have and Do not Have a Prior Primary or Revision Arthroplasty?

BACKGROUND: We sought to evaluate the risk of aseptic revision in total knee arthroplasty (TKA) patients who have and do not have a history of primary or revision arthroplasty of a different major joint. METHODS: We conducted a matched cohort study using data from Kaiser Permanente's arthroplasty registries. Patients who underwent primary unilateral TKA (index knee) were identified (2009-2018). Two matches based on exposure history were performed: (1) 33,714 TKAs with a history of primary arthroplasty of a different joint (contralateral knee, either hip, and/or either shoulder) were matched to 67,121 TKAs without an arthroplasty history and (2) 597 TKAs with a history of aseptic revision in a different joint were matched to 1,190 TKAs with a history of a prior arthroplasty in a different joint, but without any revision. After the matches were performed, Cox regressions were used to evaluate aseptic revision risk of the index knee using the no history groups as the reference in regression models. RESULTS: No difference in aseptic revision risk for the index knee was observed when comparing patients who had a prior primary arthroplasty in a different joint to those who did not have an arthroplasty history (hazard ratio = 0.95, 95% CI = 0.86-1.06). Those patients who did not have any prior aseptic revision history in a different joint had higher risk of aseptic revision in the index knee (hazard ratio = 2.06, 95% CI = 1.17-3.63). CONCLUSION: Patients who had a prior revision history had over a 2-fold higher risk of aseptic revision in the index knee, warranting close surveillance of these patients. LEVEL OF EVIDENCE: Level III.

Temporal Trends in Deep Surgical Site Infections After Six Orthopaedic Procedures Over a 12-year Period Within a US-based Healthcare System.

INTRODUCTION: Centers of excellence and bundled payment models have driven perioperative optimization and surgical site infection (SSI) prevention with decolonization protocols and antibiotic prophylaxis strategies. We sought to evaluate time trends in the incidence of deep SSI and its causative organisms after six orthopaedic procedures in a US-based integrated healthcare system. METHODS: We conducted a population-level time-trend study using data from Kaiser Permanente's orthopaedic registries. All patients who underwent primary anterior cruciate ligament reconstruction (ACLR), total knee arthroplasty (TKA), elective total hip arthroplasty (THA), hip fracture repair, shoulder arthroplasty, and spine surgery were identified (2009 to 2020). The annual incidence of 90-day deep SSI was identified according to the National Healthcare Safety Network/Centers for Disease Control and Prevention guidelines with manual chart validation for identified infections. Poisson regression was used to evaluate annual trends in SSI incidence with surgical year as the exposure of interest. Annual trends in overall incidence and organism-specific incidence were considered. RESULTS: The final study sample was composed of 465,797 primary orthopaedic procedures. Over the 12-year study period, a decreasing trend in deep SSI was observed for ACLR and hip fracture repair. Although there was variation in incidence rates for specific operative years for TKA, elective THA, shoulder arthroplasty, and spine surgery, no consistent decreasing trends over time were found. Decreasing rates of Staphylococcus aureus infections over time after hip fracture repair, shoulder arthroplasty, and spine surgery and decreasing trends in antibiotic resistance after elective THA and spine surgery were also observed. Increasing trends of polymicrobial infections were observed after TKA and Cutibacterium acnes after elective THA. CONCLUSIONS: The overall incidence of deep SSI after six orthopaedic procedures was rare. Decreasing SSI rates were observed for ACLR and hip fracture repair within our US-based healthcare system. Polymicrobial infections after TKA and Cutibacterium acnes after elective THA warrant closer surveillance. LEVEL OF EVIDENCE: IV.

The Association Between Cement Viscosity and Revision Risk After Primary Total Knee Arthroplasty.

BACKGROUND: Recent case series have reported early failure with the use of high-viscosity cement (HVC) in total knee arthroplasty (TKA). We evaluated revision risk after TKA with HVC compared with medium-viscosity cement (MVC) in a large cohort. METHODS: We conducted a cohort study using data from Kaiser Permanente's Total Joint Replacement Registry. Patients who underwent fully cemented primary TKA for osteoarthritis were identified (2001-2018). Only posterior-stabilized, fixed-mobility designs of the 3 highest-volume implant systems (DePuy PFC, Zimmer NexGen, and Zimmer Persona) were included to mitigate confounding from implant characteristics. Palacos (Zimmer/Heraeus) and Simplex (Stryker) cements comprised the HVC and MVC exposure groups, respectively. Propensity score-weighted Cox proportional hazards regression was used to evaluate risk for any revision during follow-up and risk for revision from aseptic loosening specifically. RESULTS: The final cohort comprised 76,052 TKAs, 41.1% using MVC. The crude 14-year cumulative revision probability was 4.55% and 5.12% for TKA with MVC and HVC, respectively. In propensity score-weighted Cox models, MVC compared with HVC had a lower risk of any revision (hazard ratio = 0.82, 95% confidence interval = 0.70-0.95) while no difference was observed for revision from aseptic loosening (hazard ratio = 0.80, 95% confidence interval = 0.56-1.13). CONCLUSION: While we observed a lower risk for any revision with the use of Simplex MVC compared with Palacos HVC, we did not observe a difference in revision for aseptic loosening specifically. Given the widespread use of HVC, additional research to investigate other HVC and potential mechanisms for failure outside of loosening is warranted. LEVEL OF EVIDENCE: Level III.

Commercially Prepared Antibiotic-Loaded Bone Cement and Infection Risk Following Cemented Primary Total Knee Arthroplasty.

BACKGROUND: The efficacy of commercially available antibiotic-loaded bone cement (ABC) in preventing infection in total knee arthroplasty (TKA) is unclear. We sought to determine the effectiveness of commercially available ABC in reducing the risk of infection following TKA, both overall and among 3 subgroups of patients with a higher risk of infection (diabetes, body mass index ≥35 kg/m, and American Society of Anesthesiologists classification ≥3), and to evaluate the association between the use of ABC and the risks of aseptic revision and revision for aseptic loosening. METHODS: The Kaiser Permanente Total Joint Replacement Registry was utilized to evaluate 87,018 primary cemented TKAs performed from 2008 to 2016. The primary outcome was time to infection (90-day deep infection or septic revision). Reduced infection risk with ABC relative to regular cement was tested with use of propensity-score-weighted Cox proportional-hazards models with superiority and noninferiority testing. All analyses were replicated for each of the 3 high-risk subgroups. For the secondary revision outcomes, propensity-score-weighted Cox proportional-hazards models were utilized. RESULTS: Regular cement was found to be noninferior to ABC with respect to risk infection (hazard ratio [HR], 1.14; 95% confidence interval [CI], 0.93 to 1.40) and cost across all TKA patients. However, a lower risk of infection was observed with ABC among TKA patients with diabetes (HR, 0.72; 95% CI, 0.52 to 0.99). There was no evidence of a difference in risk of revision for ABC compared with regular cement. CONCLUSIONS: We found that the additional cost associated with the use of commercially prepared ABC in primary TKA was not justified in all patients; however, the risk of reduction was lower among patients with diabetes who received ABC. Further study is warranted to identify the efficacy of ABC among other high-risk populations. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Prolonged Opioid Use After Primary Total Knee and Total Hip Arthroplasty: Prospective Evaluation of Risk Factors and Psychological Profile for Depression, Pain Catastrophizing, and Aberrant Drug-Related Behavior.

BACKGROUND: Forty percent of patients continue to use opioids at 3 months after joint arthroplasty. We sought to identify clinical and psychological risk factors associated with prolonged opioid use. METHODS: In this prospective study, psychological profile data were collected preoperatively. Prolonged use was defined as dispensation of an opioid after 90 days. Logistic regressions were used for univariate and multivariate modeling and to create receiver operating characteristic curves. A backward stepwise regression analysis was used to select significant factors in the multivariable model. RESULTS: The study included 258 patients (163 total knee arthroplasty, 95 total hip arthroplasty). 29.84% of patients were on preoperative opioids and 14% (37 of 258) of patients had prolonged use of opioids. In the univariate analysis, age <65, associated back pain, chronic pain syndrome or fibromyalgia, prior opioid use, drug potency of more than 10 morphine equivalent, and total score on Opioid Risk Tool of more than 7 were associated with prolong use. In the multivariate analysis, age <65, associated back pain, chronic pain, and preoperative use of opioids were significant risk factors for prolonged use (combined area under the curve = 0.83). Preoperative opioid use had the highest area under the curve = 0.72 (P = .0005). Psychological profile tests did not predict prolonged opioid use. CONCLUSION: Preoperative opioid use was the strongest predictor of postoperative prolonged opioid use. Younger age, associated backpain, and chronic pain syndrome were the other identified risk factors. Screening tools to detect aberrant drug-related behavior may be more helpful than those for depression or pain catastrophizing.

Preoperative Risk Factors for Opioid Utilization After Total Hip Arthroplasty.

BACKGROUND: Opioid prescriptions following orthopaedic procedures may contribute to the opioid epidemic in the United States. Risk factors for greater and prolonged opioid utilization following total hip arthroplasty have yet to be fully elucidated. We sought to determine the prevalence of preoperative and postoperative opioid utilization in a cohort of patients who underwent total hip arthroplasty and to identify preoperative risk factors for prolonged utilization of opioids following total hip arthroplasty. METHODS: A cohort study of patients who underwent primary elective total hip arthroplasty at Kaiser Permanente from January 2008 to December 2011 was conducted. The number of opioid prescriptions dispensed per 90-day period after total hip arthroplasty (up to 1 year) was the outcome of interest. The risk factors evaluated included preoperative analgesic medication use, patient demographic characteristics, comorbidities, and other history of chronic pain. Poisson regression models were used, and relative risks (RRs) and 95% confidence intervals (CIs) are presented. RESULTS: Of the 12,560 patients who underwent total hip arthroplasty and were identified, 58.5% were female and 78.6% were white. The median age was 67 years (interquartile range, 59 to 75 years). Sixty-three percent of patients filled at least 1 opioid prescription in the 1 year prior to the total hip arthroplasty. Postoperative opioid use went from 88.6% in days 1 to 90 to 24% in the last quarter. An increasing number of preoperative opioid prescriptions was associated with a greater number of prescriptions over the entire postoperative period, with an RR of 1.10 (95% CI, 1.10 to 1.11) at days 271 to 360. Additional factors associated with greater utilization over the entire year included black race, chronic pulmonary disease, anxiety, substance abuse, and back pain. Factors associated with greater utilization in days 91 to 360 (beyond the early recovery phase) included female sex, higher body mass index, acquired immunodeficiency syndrome, peripheral vascular disease, and history of non-specific chronic pain. CONCLUSIONS: We identified preoperative factors associated with greater and prolonged opioid utilization long after the early recovery period following total hip arthroplasty. Patients with these risk factors may benefit from targeted multidisciplinary interventions to mitigate the risk of prolonged opioid use. CLINICAL RELEVANCE: Opioid prescriptions following orthopaedic procedures are one of the leading causes of chronic opioid use; strategies to reduce the risk of misuse and abuse are needed. At 1 year postoperatively, almost one-quarter of patients who underwent total hip arthroplasty used opioids in the last 90 days of the first postoperative year, which makes understanding risk factors associated with postoperative opioid utilization imperative.

An international comparison of THA patients, implants, techniques, and survivorship in Sweden, Australia, and the United States.

Background and purpose - International comparisons of total hip arthroplasty (THA) practices and outcomes provide an opportunity to enhance the quality of care worldwide. We compared THA patients, implants, techniques, and survivorship in Sweden, Australia, and the United States. Patients and methods - Primary THAs due to osteoarthritis were identified using Swedish (n = 159,695), Australian (n = 279,693), and US registries (n = 69,641) (2003-2015). We compared patients, practices, and implant usage across the countries using descriptive statistics. We evaluated time to all-cause revision using Kaplan-Meier survival curves. We assessed differences in countries' THA survival using chi-square tests of survival probabilities. Results - Sweden had fewer comorbidities than the United States and Australia. Cement fixation was used predominantly in Sweden and cementless in the United States and Australia. The direct anterior approach was used more frequently in the United States and Australia. Smaller head sizes (≤ 32 mm vs. ≥ 36 mm) were used more often in Sweden than the United States and Australia. Metal-on-highly cross-linked polyethylene was used more frequently in the United States and Australia than in Sweden. Sweden's 5- (97.8%) and 10-year THA survival (95.8%) was higher than the United States' (5-year: 97.0%; 10-year: 95.2%) and Australia (5-year: 96.3%; 10-year: 93.5%). Interpretation - Patient characteristics, surgical techniques, and implants differed across the 3 countries, emphasizing the need to adjust for demographics, surgical techniques, and implants and the need for global standardized definitions to compare THA survivorship internationally.

Association of Type and Frequency of Postsurgery Care with Revision Surgery after Total Joint Replacement.

CONTEXT: Postmarket surveillance is limited in the ability to detect medical device problems. Electronic health records can provide real-time information that might help with device surveillance. Specifically, the frequency of postsurgery care might indicate early problems and determine high-risk patients requiring more active surveillance. OBJECTIVE: To evaluate whether intensity of postsurgery care is associated with revision risk after total joint arthroplasty (TJA). DESIGN: Using an integrated health care system's TJA registry, we identified primary TJA performed between April 2001 and July 2013 (22,953 knees and 9904 hips). Survival analyses evaluated the frequency of specific types of outpatient and inpatient utilization 0 to 90 and 91 to 180 days postoperatively and revision risk. MAIN OUTCOME MEASURES: Revision surgery occurring at least 6 months after primary TJA. RESULTS: Knee arthroplasty recipients with 3 or more outpatient orthopedic allied health/nurse visits within 90 days had a 2.2 times (95% confidence interval [CI] = 1.6-2.9) higher risk of revision within the first 2 years postoperatively and 10.1 times higher risk (95% CI = 7.6-13.3) after 2 years. Compared with hip arthroplasty recipients who had 0 to 3 visits, patients with 6 or more outpatient orthopedic office visits within 90 days had a 15.7 times (95% CI = 5.7-42.9) higher risk of revision. Similar results were observed for 91-day to 180-day visits. CONCLUSION: Future studies are needed to determine if more specific data on reasons for the higher frequency of outpatient visits can refine these findings and elicit more specific recommendations for TJA devices.

Opioid Prescribers to Total Joint Arthroplasty Patients Before and After Surgery: The Majority Are Not Orthopedists.

BACKGROUND: Improved narcotic pain management after total joint arthroplasty (TJA) is necessary to help battle the opioid epidemic. The goal of this study was to determine the sources of prescriptions prescribed to TJA patients. METHODS: An evaluation of opioid use in patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA) was performed between 2008 and 2012. Using a Total Joint Replacement Registry and pharmacy data, opioids dispensed to TJA patients were identified. The main outcome of interest was who prescribed opioids to patients in the year before and after surgery. RESULTS: Primary care (pre-TKA 31% TKA, post-TKA 38%, pre-THA 34%, post-THA 40%) and internal medicine (27% pre-TKA, post-TKA 37%, pre-THA 32%, post-THA 40%) were the highest prescribers in the year before, and after, TJA. For TKA patients, orthopedists prescribed 9% of the opioids in the year before surgery, 47% in days 1-90 after surgery, and 14% in days 271-360. Similarly, in THA patients, orthopedists prescribed 14% of the opioids in the year before surgery, 40% in days 1-90 after surgery, and 14% in days 271-360. CONCLUSION: Patients receive opioid prescriptions from multiple physician types before, and after, TJA. The majority of preoperative, and late postoperative, narcotics were not provided by their surgeons. Orthopedic surgeons may not even know that their TJA patients continue to receive opioids. Coordination of opioid care with health-care providers and greater communication with patients on narcotic use expectations should be promoted.

Body Mass Index Is Associated With All-cause Mortality After THA and TKA.

BACKGROUND: Both obesity and underweight are associated with a higher risk of mortality in adulthood, but the association between mortality after arthroplasty and extreme ranges of body mass index (BMI) have not been evaluated beyond the first year. QUESTIONS/PURPOSES: The purpose of this study was to investigate the association between BMI and all-cause mortality after TKA and THA. METHODS: Data from two arthroplasty registries, the St Vincent's Melbourne Arthroplasty (SMART) Registry from Australia and the Kaiser Permanente Total Joint Replacement Registry (KPTJRR) from the United States, were used to identify patients aged ≥ 18 years undergoing elective TKAs and THAs between January 1, 2002, and December 31, 2013. Same-day bilateral THA and hemiarthroplasties were excluded. All-cause mortality was recorded from the day of surgery to the end of the study (December 31, 2013). Data capture was complete for the SMART Registry. No patients were lost to followup in the KPTJRR cohort and 2959 (5%) THAs and 5251 (5%) TKAs had missing data. Cox proportional hazard regression was used to estimate the all-cause mortality associated with six BMI categories: underweight (< 18.5 kg/m), normal weight (18.5-24.9 kg/m), overweight (25.0-29.9 kg/m), obese class I (30.0-34.9 kg/m), obese class II (35.0-39.9 kg/m), and obese class III (> 40 kg/m). For TKA, the SMART cohort had a median followup of 5 years (range, 0-12 years) and the KPTJRR cohort had a median followup of 4 years (range, 0-12 years). For THA, the SMART cohort had a median followup of 5 years (range, 0-12 years) and the KPTJRR cohort had a median followup of 4 years (range, 0-12 years). RESULTS: In both the Australian and US cohorts, being underweight (Australia: hazard ratio [HR], 3.72; 95% confidence interval [CI], 1.94-7.08; p < 0.001 and United States: HR, 1.88; 95% CI, 1.33-2.64; p < 0.001) was associated with higher all-cause mortality after TKA, whereas obese class I (Australia: HR, 0.66; 95% CI, 0.47-0.92; p = 0.015; United States: HR, 0.71; 95% CI, 0.66-0.78; p < 0.001) or obese class II (Australia: HR, 0.54; 95% CI, 0.35-0.82; p = 0.004; United States: HR, 0.73; 95% CI, 0.66-0.81; p < 0.001) was associated with lower mortality when compared with normal-weight patients. In the US cohort, being overweight was also associated with a lower risk of mortality (HR, 0.76; 95% CI, 0.71-0.82; p < 0.001). In the US cohort, being underweight had a higher risk of mortality after THA (HR, 2.09; 95% CI, 1.65-2.64; p < 0.001), whereas those overweight (HR, 0.73; 95% CI, 0.67-0.80; p < 0.001), obese class I (HR, 0.68; 95% CI, 0.62-0.75; p < 0.001), or obese class II (HR, 0.71; 95% CI, 0.62-0.81; p < 0.001) were at a lower risk of mortality after THA when compared with normal-weight patients. In patients undergoing THA in the Australian cohort, we observed no association between BMI and risk of death. CONCLUSIONS: We found that even severe obesity is not associated with a higher risk of death after arthroplasty. Patients should be informed of this when considering surgery. Clinicians should be cautious when considering total joint arthroplasty in underweight patients without first considering their nutritional status. LEVEL OF EVIDENCE: Level III, therapeutic study.

Patient Factors Associated With Prolonged Postoperative Opioid Use After Total Knee Arthroplasty.

BACKGROUND: Pain persists in a moderate proportion of patients after total knee arthroplasty (TKA). Identifying patient factors that are associated with persistent pain may lead to improved care. PURPOSE: The purpose of the study was to identify preoperative factors associated with increased opioid prescriptions after TKA. METHODS: A retrospective cohort study of TKAs in an integrated health-care system (January 2008-December 2011) was conducted. The number of opioid prescriptions per 90-day period after TKA (up to 1 year), was the outcome of interest. Patient risk factors that were evaluated included demographics, pain prescriptions, comorbidities, and chronic pain conditions. Multivariable Poisson regression models were employed. RESULTS: The median age for 23,726 patients was 67 years. Before surgery, 60.0% used opioids. Three months after surgery, 41.2% of patients continued using opioids. Factors associated with greater opioid use included: younger age (odds ratio [OR] = 0.83, 95% confidence interval [CI] 0.82-0.84 per 10-year increase), liver disease (OR = 1.11, 95% CI 1.06-1.16), preoperative nonsteroidal anti-inflammatory drug use (OR = 1.09, 95% CI 1.07-1.10), anxiety (OR = 1.05, 95% CI 1.03-1.08), substance abuse (OR = 1.03, 95% CI 1.00-1.06), diabetes mellitus (OR = 1.03, 95% CI 1.01-1.05), preoperative opioid use (OR = 1.04, 95% CI 1.04-1.04), back pain (OR = 1.23, 95% CI 1.18-1.127), congestive heart failure (OR = 1.16, 95% CI 1.06-1.27), depression (OR = 1.14, 95% CI 1.09-1.18), fibromyalgia (OR = 1.10, 95% CI 1.02-1.18), hypertension (OR = 1.06, 95% CI 1.02-1.10), nonspecific chronic pain (OR = 1.06, 95% CI 1.02-1.10), black race (OR = 1.17, 95% CI 1.12-1.23), and chronic lung disease (OR = 1.05, 95% CI 1.01-1.10). CONCLUSION: Several preoperative factors were associated with prolonged opioid use after TKA, and their identification can assist providers guide pain management. Avoidance or weaning of preoperative opioids should be considered.

Meta-analysis of individual registry results enhances international registry collaboration.

Background and purpose - Although common in medical research, meta-analysis has not been widely adopted in registry collaborations. A meta-analytic approach in which each registry conducts a standardized analysis on its own data followed by a meta-analysis to calculate a weighted average of the estimates allows collaboration without sharing patient-level data. The value of meta-analysis as an alternative to individual patient data analysis is illustrated in this study by comparing the risk of revision of porous tantalum cups versus other uncemented cups in primary total hip arthroplasties from Sweden, Australia, and a US registry (2003-2015). Patients and methods - For both individual patient data analysis and meta-analysis approaches a Cox proportional hazard model was fit for time to revision, comparing porous tantalum (n = 23,201) with other uncemented cups (n = 128,321). Covariates included age, sex, diagnosis, head size, and stem fixation. In the meta-analysis approach, treatment effect size (i.e., Cox model hazard ratio) was calculated within each registry and a weighted average for the individual registries' estimates was calculated. Results - Patient-level data analysis and meta-analytic approaches yielded the same results with the porous tantalum cups having a higher risk of revision than other uncemented cups (HR (95% CI) 1.6 (1.4-1.7) and HR (95% CI) 1.5 (1.4-1.7), respectively). Adding the US cohort to the meta-analysis led to greater generalizability, increased precision of the treatment effect, and similar findings (HR (95% CI) 1.6 (1.4-1.7)) with increased risk of porous tantalum cups. Interpretation - The meta-analytic technique is a viable option to address privacy, security, and data ownership concerns allowing more expansive registry collaboration, greater generalizability, and increased precision of treatment effects.

Persistent Opioid Use Following Total Knee Arthroplasty: A Signal for Close Surveillance.

BACKGROUND: Prolonged opioid use following total knee arthroplasty (TKA) has not been extensively studied. METHODS: A cohort study of primary TKA for osteoarthritis using an integrated healthcare system and Total Joint Replacement Registry (January 2008-December 2011) was conducted. Opioid use during the first year after TKA was the exposure of interest and cumulative daily oral morphine equivalent (OME) amounts were calculated. Total postsurgical OME per 90-day exposure periods were categorized into quartiles. The end point was aseptic revision surgery. Survival analyses were conducted and hazard ratios (HRs) were adjusted for age, gender, prior analgesic use, opioid-related comorbidities, and chronic pain diagnoses. RESULTS: A total of 24,105 patients were studied. After the initial 90-day postoperative period, 41.5% (N = 9914) continued to use opioids. Also, 155 (0.6%) revisions occurred within 1 year and 377 (1.6%) within 5 years. Compared to patients not taking any opioids, patients using medium-low to high OME after the initial 90-day period had a higher adjusted risk of 1-year revision, ranging from HR = 2.4 (95% confidence interval, 1.3-4.5) to HR = 33 (95% confidence interval, 10-110) depending on the OME and time period. CONCLUSION: Patients who require opioids beyond 90 days after TKA warrant close follow-up.

An underlying diagnosis of osteonecrosis of bone is associated with worse outcomes than osteoarthritis after total hip arthroplasty.

BACKGROUND: Well-designed studies of complications and readmission rates in patients undergoing total hip arthroplasty (THA) with osteonecrosis are lacking. Our objective was to examine if a diagnosis of osteonecrosis was associated with complications, mortality and readmission rates after THA. METHODS: We analyzed prospectively collected data from an integrated healthcare system's Total Joint Replacement Registry of adults with osteonecrosis vs. osteoarthritis (OA) undergoing unilateral primary THA during 2001-2012, in an observational cohort study. We examined mortality (90-day), revision (ever), deep (1 year) and superficial (30-day) surgical site infection (SSI), venous thromboembolism (VTE, 90-day), and unplanned readmission (90-day). Age, gender, race, body mass index, American Society of Anesthesiologists class, and diabetes were evaluated as confounders. We used logistic or Cox regression to calculate odds or hazard ratios (OR, HR) with 95% confidence intervals (CI). RESULTS: Of the 47,523 primary THA cases, 45,252 (95.2%) had OA, and 2,271 (4.8%) had osteonecrosis. Compared to the OA, patients with osteonecrosis were younger (median age 55 vs. 67 years), and were less likely to be female (42.5% vs. 58.3%) or White (59.8% vs. 77.4%). Compared to the OA, the osteonecrosis cohort had higher crude incidence of 90-day mortality (0.7% vs. 0.3%), SSI (1.2% vs. 0.8%), unplanned readmission (9.6% vs. 5.2%) and revision (3.1% vs. 2.4%). After multivariable-adjustment, patients with osteonecrosis had a higher odds/hazard of mortality (OR: 2.48; 95% CI:1.31-4.72), SSI (OR: 1.67, 95%CI:1.11-2.51), unplanned 90-day readmissions (OR: 2.20; 95% CI:1.67-2.91) and a trend towards higher revision rate 1-year post-THA (HR: 1.32; 95% CI: 0.94-1.84), than OA patients. CONCLUSIONS: Compared to OA, a diagnosis of osteonecrosis was associated with worse outcomes post-THA. A detailed preoperative discussion including the risk of complications is needed for informed consent from patients with osteonecrosis.

Bilateral Simultaneous vs Staged Total Knee Arthroplasty: A Comparison of Complications and Mortality.

BACKGROUND: The purpose of this study was to compare the complications and mortality between bilateral simultaneous total knee arthroplasty (BTKA-Simultaneous) and bilateral staged TKA (BTK-Staged) while adjusting for differences in patient, surgeon, and hospital characteristics. METHODS: An integrated health care system total joint registry was used to compare patients undergoing BTKA-Simultaneous to BTKA-Staged. For outcomes related to revision and infection, the sample included 11,118 patients, and for outcomes of death, acute myocardial infarction, stroke, and venous thromboembolism, a subsample of 7991 patients with comorbidity data was selected. RESULTS: Overall death and complications in both groups were rare. The complication rates for BTKA-Simultaneous and BTKA-Staged were comparable: aseptic revision (1.17% vs 0.9%), septic revision/deep infection (0.8% vs 0.7%), death (0.28% vs 0.1%), and adverse events (2.49% vs 1.97%). In the adjusted models, there were no significant differences in any of the outcomes between the 2 groups. CONCLUSION: There is a lack of evidence to support superiority of either BTKA-Simultaneous or BTKA-Staged.

Postoperative opioid use as an early indication of total hip arthroplasty failure.

Background and purpose - A criticism of total hip arthroplasty (THA) survivorship analysis is that revisions are a late and rare outcome. We investigated whether prolonged opioid use is a possible indicator of early THA failure. Patients and methods - We conducted a cohort study of THAs registered in a total joint replacement registry from January 2008 to December 2011. 12,859 patients were evaluated. The median age was 67 years and 58% were women. Opioid use in the year after surgery was the exposure of interest, and the cumulative daily amounts of oral morphine equivalents (OMEs) were calculated. Post-THA OMEs per 90 day periods were categorized into quartiles. The endpoints were 1- and 5-year revisions. Results - After the first 90 days, 27% continued to use opioids. The revision rate was 0.9% within a year and 1.7% within 5 years. Use of medium-low (100-219 mg), medium-high (220-533 mg), and high (≥ 534 mg) amounts of OMEs in days 91-180 after surgery was associated with a 6 times (95% confidence interval (CI): 3-15), 5 times (CI: 2-13), and 11 times (CI: 2.9-44) higher adjusted risk of 1 year revision, respectively. The use of medium-low and medium-high amounts of OMEs in days 181-270 after surgery was associated with a 17 times (CI: 6-44) and 14 times (95% CI: 4-46) higher adjusted risk of 1-year revision. There was a similar higher risk of 5-year revision. Interpretation - Persistent postoperative use of opioids was associated with revision THA surgery in this cohort, and it may be an early indicator of potential surgical failures.

Lower Total Knee Arthroplasty Revision Risk Associated With Bisphosphonate Use, Even in Patients With Normal Bone Density.

BACKGROUND: Bisphosphonates (BPs) are associated with lower total knee arthroplasty (TKA) revision risk, but the effect of bone mineral density has not been evaluated. METHODS: A cohort of 34,116 primary TKA patients was evaluated with revision surgery and periprosthetic fractures as end points. BP usage was the exposure of interest. Bone quality (normal, osteopenia, and osteoporosis) and patient age (<65 vs ≥65 years) were evaluated as effect modifiers of risk estimates. RESULTS: Of the patients, 19.6% were BP users. In BP users, 0.5% underwent an aseptic revision; and 0.6%, a periprosthetic fracture. In non-BP users, 1.6% underwent aseptic revision; and 0.1%, a periprosthetic fracture. CONCLUSION: Bisphosphonate use was associated with lower risk of revision in all bone quality categories in those older than 65 years. The risk of periprosthetic fractures was higher for patients on BP.

Association of Bisphosphonate Use and Risk of Revision After THA: Outcomes From a US Total Joint Replacement Registry.

BACKGROUND: Total hip arthroplasty (THA) is often performed in patients who are older and may take bisphosphonates to treat a variety of conditions, most commonly osteoporosis. However, the clinical effects of bisphosphonate use on patients who have undergone THA are not well described. QUESTIONS/PURPOSES: (1) Is bisphosphonate use in patients with osteoarthritis undergoing primary THA associated with a change in the risk of all-cause revision, aseptic revision, or periprosthetic fracture compared with patients not treated with bisphosphonates? (2) Does the risk of bisphosphonate use and revision and periprosthetic fracture vary by patient bone mineral density and age? METHODS: A retrospective cohort study of 12,878 THA recipients for the diagnosis of osteoarthritis was conducted; 17.8% of patients were bisphosphonate users. Data sources for this study included a joint replacement registry (93% voluntary participation) and electronic health records and an osteoporosis screening database with complete capture of cases as part of the Kaiser Permanente integrated healthcare system. The endpoints for this study were revision surgery for any cause, aseptic revision, and periprosthetic fracture. The exposure of interest was bisphosphonate use; patients were considered users if prescriptions were continuously refilled for a period equal to or longer than 6 months. Bone quality (based on dual-energy x-ray absorptiometery ordered based on the National Osteoporosis Foundation's clinical guidelines taken within 5 years of the THA) and patient age (< 65 versus ≥ 65 years) were evaluated as effect modifiers. Patient, surgeon, and hospital factors were evaluated as confounders. Cox proportional hazards models were used. Hazard ratios (HRs) and 95% confidence intervals (CIs) were determined. RESULTS: Age- and sex-adjusted risks of all-cause (HR, 0.50; 95% CI, 0.33-0.74; p < 0.001) and aseptic revision (HR, 0.53; 95% CI, 0.34-0.81; p = 0.004) was lower in bisphosphonate users than in nonusers. The adjusted risk of periprosthetic fractures in patients on bisphosphonates was higher than in patients not on bisphosphonates (HR, 1.92; 95% CI, 1.13-3.27; p = 0.016). Lower risks of all-cause revision and aseptic revision were observed in patients with osteopenia (HR, 0.49; 95% CI, 0.29-0.84; and HR, 0.53; 95% CI, 0.29-0.99, respectively) and osteoporosis (HR, 0.22; 95% CI, 0.08-0.62; and HR, 0.33; 95% CI, 0.11-0.99, respectively). CONCLUSIONS: Patients considered bisphosphonate users who underwent THA had a lower risk for revision surgery. Bisphosphonate use was associated with a higher risk of periprosthetic fractures in younger patients with normal bone quantity. Evaluation of bone quality and bisphosphonate use for the diagnosis of osteoporosis is encouraged in patients with osteoarthritis who are candidates for primary THA. Further research is required to determine the optimal duration of therapy because long-term bisphosphonate use has been associated with atypical femur fractures. LEVEL OF EVIDENCE: Level III, therapeutic study.