Days Of Total Hip Arthroplasty Research Articles

Statin Use is Associated with Decreased Venous Thromboembolism Events Following Total Hip Arthroplasty: A Matched Retrospective Cohort Study.

Despite advances in surgical techniques and postoperative prophylactic protocols, venous thromboembolism (VTE) events remain an important source of morbidity following total hip arthroplasty (THA). Prior research in cardiology and other surgical fields has suggested that statin medications may have a protective effect against VTE. Our study aimed to: 1) Assess if preoperative statin use was associated with decreased rates of VTE following THA, and 2) conduct a subgroup analysis of statin intensity and VTE events. A total of 1,154 patients who had preoperative statin use for at least four weeks before surgery and who underwent primary THA at a large, urban academic center between January 1, 2012, and June 1, 2023, were identified. The 90-day postoperative VTE events, deep vein thrombosis (DVT), pulmonary embolism (PE), emergency department (ED) visits, reoperations, and readmission rates were collected from institutional coding software. Mortality rate in the 90-day postoperative period was also measured. Propensity matching was used to control for demographics and selected comorbidities. Preoperative statin use was associated with significantly lower rates of 90-day VTE events (Statin: 0.43% versus No-Statin: 1.13%, P = 0.047). There were no significant differences in 90-day PE, DVT, ED visit, readmission, or reoperation rates. There were no deaths within 90 days of THA in either group. Subgroup analysis of statin intensity revealed no significant differences in any outcomes measured between high-intensity, medium-intensity, and low-intensity statin groups. Preoperative statin use is associated with significantly lower rates of VTE events in the 90-day postoperative period following THA. Further research into the effect of statins on post-THA VTE is warranted.

EFFECT OF BODY MASS INDEX ON THE RISK OF POSTOPERATIVE COMPLICATIONS FOLLOWING TOTAL HIP ARTHROPLASTY

While obesity is associated with an increased risk of complications after total hip arthroplasty (THA) the relationship between body mass index (BMI) and the risk of early postoperative complications has not been fully characterized. This study sought to describe the relationship between BMI and the risk of early postoperative complications, including periprosthetic joint infection (PJI), composite surgical, and composite medical complications.Primary, elective THAs performed from 2016–2021 were identified using the Premier Healthcare Database (PHD). The study's primary outcome was the diagnosis of PJI within 90 days of THA. Using BMI as a continuous variable, logistic regression was used to develop restricted cubic splines (RCSs) to determine the impact of BMI on PJI risk. Bootstrap simulation was used to identify an inflection point in the final RCS model. The same technique was used to characterize the effects of BMI on composite medical and surgical complications.We found that PJI risk increased exponentially beyond a BMI cutpoint of 37.4 kg/m2. Relative to the cutpoint, patients with a BMI of 40 or 50 kg/m2 were at a 1.22- and 2.55-fold increased risk of developing PJI, respectively. Surgical complications increased at a BMI of 32 kg/m2 and medical complications increased at a BMI of 39 kg/m2. Relative to these cutpoints, patients with a BMI of 50 kg/m2 were at a 1.36- and 2.07-fold increased risk of developing medical and surgical complications, respectively.The results of this study indicate a non-linear relationship between patient BMI and early postoperative risk of PJI, composite medical complications, and composite surgical complications following THA. The identified cutpoints with associated odds ratios can serve as tools to help risk-stratify and counsel patients seeking primary THA.

Early Prosthetic Hip Dislocation: Does the Timing of the Dislocation Matter?

BackgroundEarly dislocation following total hip arthroplasty (THA) is a common reason for revision. The purpose of this study was to determine if the acuity of the dislocation episode affects the risk of revision surgery. MethodsA retrospective review of a national, all-payer administrative database comprised of claims from 2010 to 2020 was used to identify patients who had a prosthetic hip dislocation at various postoperative time intervals (0 to 7, 7 to 30, 30 to 60, and 60 to 90 days). Of the 45,352 primary unilateral THA patients who had sufficient follow-up, there were 2,878 dislocations within 90 days. Dislocators were matched 1:1 based on age, sex, and a comorbidity index with a control group (no dislocation). Demographics, surgical indications, comorbidities, ten-year revision rates, and complications were compared among cohorts. Multivariable logistic regression analysis was performed to identify risk factors for revision THA following early dislocation. ResultsAmong matched cohorts, dislocation at any time interval was associated with significantly increased odds of subsequent 10-years revision (OR [odds ratio] = 25.60 to 33.4, P < .001). Acute dislocators within 7 days did not have an increased risk of all cause revisions at 10 years relative to other early dislocators. Revision for indication of instability decreased with time to first dislocation (<7 days: 85.7% versus 60 to 90 days: 53.9%). Primary diagnoses of posttraumatic arthritis (OR = 2.53 [1.84 to 3.49], P < .001), hip fracture (OR = 3.8 [2.53 to 5.72], P < .001), and osteonecrosis (OR = 1.75 [1.12 to 2.73], P = .010) were most commonly associated with revision surgery after an early dislocation. ConclusionsDislocation within 90 days of THA is associated with increased odds of subsequent revision. Early dislocation within 7 days of surgery has similar all cause revision-free survivorship, but an increased risk of a subsequent revision for instability when compared to patients who dislocated within 7 to 90 days

Cost-effectiveness of enoxaparin versus aspirin in the prevention of venous thromboembolism after total hip or knee arthroplasty: an analysis from the CRISTAL cluster-randomized trial.

The aim of this study was to evaluate the healthcare costs and benefits of enoxaparin compared to aspirin in the prevention of symptomatic venous thromboembolism (VTE) after total hip arthroplasty (THA) or total knee arthroplasty (TKA) using data from the CRISTAL trial. This trial-based economic analysis reports value for money as incremental cost per quality-adjusted life-year (QALY) gained in 2022 Australian dollars, compared to a single threshold value of AUD$70,000 per QALY. Event costs were estimated based on occurrence of VTEs and bleeds, and on published guidelines for treatment. Unit costs were taken from Australian sources. QALYs were estimated using CRISTAL six-month follow-up data. Sensitivity analyses are presented that vary the cost of VTE treatment, and extend the analyses to two years. The CRISTAL trial found that enoxaparin was more effective than aspirin in preventing symptomatic VTE within 90 days of THA or TKA (risk difference 1.97% (95% confidence interval (CI) 0.54% to 3.41%; p = 0.007)). The additional cost after a THA or TKA was AUD$83 (95% CI 68 to 97) for enoxaparin, and enoxaparin resulted in an additional 0.002 QALYs (95% CI -0.002 to 0.005). Incremental cost per QALY gained was AUD$50,567 (95% CI 15,513, dominated) for enoxaparin. We can be 60% confident that the incremental cost per QALY does not exceed the willingness-to-pay threshold of AUD$70,000. Increasing the cost of VTE treatment and extension of costs and consequences to two years suggested greater confidence that enoxaparin is good value for money (70% and 63% confidence, respectively). This analysis provides strong evidence that enoxaparin thromboprophylaxis following THA or TKA reduced VTEs, but weak evidence of net economic benefits over aspirin. If the value of avoiding VTEs is high, and there is a strong likelihood of VTE-related health impairments, we can be more confident that enoxaparin is cost-effective compared to aspirin.

Risk Factors Associated with Thromboembolic Complications After total Hip Arthroplasty: An Analysis of 1,129 Pulmonary Emboli.

Venous thromboembolism (VTE) remains a dangerous complication after total hip arthroplasty (THA), despite advances in chemoprophylactic measures. This study aimed to identify risk factors of developing pulmonary embolism (PE) and deep vein thrombosis (DVT) after THA using a modern cohort of patients reflecting contemporary practices. The Premier Healthcare Database was queried for primary, elective THAs from January 1st, 2015, to December 31st, 2021. Patients who developed PE or DVT within 90 days of THA were compared with patients who did not develop any postoperative VTE. Differences in patient demographics, comorbidities, hospital factors, perioperative medications, chemoprophylactic agents, and allogeneic blood transfusion were compared between cohorts. Multivariable logistic regression models were used to identify independent risk factors of PE and DVT. In total, 544,298 THAs were identified, of which 1,129 (0.21%) developed a PE and 1,799 (0.33%) developed a DVT. Patients diagnosed with a PE had significantly higher rates of in-hospital death (2.6% vs 0.1%, P < 0.001) compared with those without a PE. Age (adjusted odds ratio: 1.02 per year, 95% confidence interval [CI]: 1.01 to 1.03) and Black race (aOR: 1.52, 95% CI: 1.24 to 1.87) were associated with an increased risk of PE. Comorbidities associated with increased risk of PE included chronic pulmonary disease (aOR: 1.58, 95% CI: 1.36 to 1.84), pulmonary hypertension (aOR: 2.06, 95% CI: 1.39 to 3.04), and history of VTE (aOR: 2.38, 95% CI: 1.98 to 2.86). Allogeneic blood transfusion (aOR: 2.40, 95% CI: 1.88 to 3.06) was also associated with an increased risk of PE while dexamethasone utilization was associated with a reduced risk (aOR: 0.83, 95% CI: 0.73 to 0.95). Increasing age; Black race; allogeneic blood transfusion; and comorbidities, including chronic pulmonary disease, pulmonary hypertension, and history of VTE, were independent risk factors of PE after THA. Given the increased mortality associated with PE, patients should be carefully evaluated for these factors and managed with an appropriate chemoprophylactic regimen.

Scoliosis Without Fusion and Increased Risk of Early Medical and Surgery-Related Complications After Total Hip Arthroplasty: A Propensity-score Analysis.

There is a paucity of literature that examines how the abnormal spinopelvic alignment of scoliosis affects outcomes after total hip arthroplasty (THA) in the absence of a lumbar fusion. Patients with a history of scoliosis (idiopathic, adolescent, degenerative, or juvenile) without fusion and those without a history of scoliosis who underwent primary THA were identified using a large national database. Ninety-day incidence of various medical complications, emergency department (ED) visit, and readmission and 1-year incidence of surgery-related complications and cost of care were evaluated in both the scoliosis and control cohorts. Propensity score matching was used to control for patient demographic factors and comorbidities as covariates. After propensity matching, 21,992 and 219,920 patients were identified in the scoliosis and control cohorts, respectively. Patients with scoliosis were at increased risk of several 90-day medical complications, including pulmonary embolism (odds ratio [OR] 1.96; P < 0.001), deep vein thrombosis (1.49; P < 0.001), transfusion (OR, 1.13; P < 0.001), pneumonia (OR, 1.37; P < 0.001), myocardial infarction (OR, 1.38; P = 0.008), sepsis (OR, 1.59; P < 0.001), acute anemia (OR, 1.21; P < 0.001), and urinary tract infection (OR, 1.1; P = 0.001). Patients with a history of scoliosis were at increased 1-year risk of revision (OR, 1.31; P < 0.001), periprosthetic joint infection (OR, 1.16; P = 0.0089), dislocation (OR, 1.581; P < 0.001), and aseptic loosening (OR, 1.39; P < 0.001) after THA. Patients with scoliosis without a history of fusion were more likely to return to the emergency department (OR, 1.26; P < 0.001) and be readmitted (OR, 1.78; P < 0.001) within 90 days of THA. Patients with even a remote history of scoliosis without fusion are at increased risk of 90-day medical and surgery-related complications after hip arthroplasty. Hip and spine surgeons should collaborate in future studies to best understand how to optimize these patients for their adult reconstructive procedures.

Early Periprosthetic Femur Fractures After Primary Cementless Total Hip Arthroplasty: High Risk of Periprosthetic Joint Infection and Subsequent Reoperation

BackgroundPeriprosthetic femur fracture (PFF) following total hip arthroplasty (THA) is a leading cause of early reoperation. The objective of this study was to compare rates of periprosthetic joint infection (PJI) and reoperation following PFFs occurring early postoperatively to those that occurred late. MethodsWe retrospectively identified 173 consecutive surgically managed PFFs following primary THA. Cases were categorized as “early” if they occurred within 90 days of THA (n = 117) or “late” if they occurred following the initial 90 days (n = 56). Mean age at time of PFF was 68 years (range, 26 to 96) and 60% were women. Mean body mass index was 29 (range, 16 to 52). Mean follow-up was 2 years (range, 0 to 13). Kaplan-Meier survival analysis estimated cumulative incidences of PJI and reoperation. ResultsEarly PFFs had higher 2-year cumulative incidence of PJI (11% versus 0%, P < .001) and reoperation (24% versus 13%, P = .110). Following early PFF, 27 patients required reoperation (ie, 13 for PJI, 5 for instability, 2 for re-fracture, 2 for painful hardware, 2 for non-union, 1 for adverse local tissue reaction, 1 for aseptic loosening, and 1 for leg-length discrepancy). Following late PFF, 5 patients required reoperation (ie, 3 for instability, 1 for re-fracture, and 1 for non-union). ConclusionsThere are greater incidences of PJIs and overall reoperations following early PFFs compared to late PFFs after THA. In addition to focusing efforts on prevention of early PFFs, surgeons should consider antiseptic interventions to mitigate the increased risk of PJI after treatment of early PFF.

Increasing risk of revision due to infection after primary total hip arthroplasty: results from the Nordic Arthroplasty Register Association.

The incidence of periprosthetic joint infection after total hip arthroplasty (THA) may be increasing. We performed time-trend analyses of risk, rates, and timing of revision due to infection after primary THAs in the Nordic countries from the period 2004-2018. 569,463 primary THAs reported to the Nordic Arthroplasty Register Association from 2004 to 2018 were studied. Absolute risk estimates were calculated by Kaplan-Meier and cumulative incidence function methods, whereas adjusted hazard ratios (aHR) were assessed by Cox regression with the first revision due to infection after primary THA as primary endpoint. In addition, we explored changes in the time span from primary THA to revision due to infection. 5,653 (1.0%) primary THAs were revised due to infection during a median follow-up time of 5.4 (IQR 2.5-8.9) years after surgery. Compared with the period 2004-2008, the aHRs for revision were 1.4 (95% confidence interval [CI] 1.3-1.5) for 2009-2013, and 1.9 (CI 1.7-2.0) for 2014-2018. The absolute 5-year rates of revision due to infection were 0.7% (CI 0.7-0.7), 1.0% (CI 0.9-1.0), and 1.2% (CI 1.2-1.3) for the 3 time periods respectively. We found changes in the time span from primary THA to revision due to infection. Compared with 2004-2008, the aHR for revision within 30 days after THA was 2.5 (CI 2.1-2.9) for 2009-2013, and 3.4 (CI 3.0-3.9) for 2013-2018. The aHR for revision within 31-90 days after THA was 1.5 (CI 1.3-1.9) for 2009-2013, and 2.5 (CI 2.1-3.0) for 2013-2018, compared with 2004-2008. The risk of revision due to infection after primary THA almost doubled, both in absolute cumulative incidence and in relative risk, throughout the period 2004-2018. This increase was mainly due to an increased risk of revision within 90 days of THA. This may reflect a "true" increase (i.e., frailer patients or more use of uncemented implants) and/or an "apparent" increase (i.e., improved diagnostics, changed revision strategy, or completeness of reporting) in incidence of periprosthetic joint infection. It is not possible to disclose such changes in the present study, and this warrants further research.

Venous thromboembolism is rare after total hip and knee joint arthroplasty with long thromboprophylaxis in Finnish fast-track hospitals

IntroductionPharmacological thromboprophylaxis effectively prevents venous thromboembolism (VTE) after total knee (TKA) and total hip arthroplasty (THA). Less is known about the influence of fast-track arthroplasty on VTE risk. We conducted a register-based study to determine the incidence of VTE after fast-track TKA and THA in Finland using long thromboprophylaxis.Materials and methodsAll primary TKAs and THAs operated during 2015–2016 in 3 fast-track hospitals were identified from the Finnish Arthroplasty Register. Pulmonary embolism (PE) and deep vein thrombosis (DVT) diagnosed in this patient cohort within 90 days of surgery were identified from the Finnish Hospital Discharge Register. The recommended length of thromboprophylaxis was 10 to 14 days for TKA and 28 days for THA during study period.ResultsDuring the study period, 3 831 THAs, 4 394 TKAs and 286 bilateral TKAs (BTKAs) were performed. Of all these patients, 60% were females. Venous thromboembolism (VTE) incidence within 90 days of surgery was 0.3% (95% CI 0.2–0.4). These VTEs comprised 10 PEs and 15 DVTs. None of the VTE patients´ died within the 90-day period.ConclusionVTE incidence is low in Finnish fast-track TKA and THA patients with long thromboprophylaxis.

Applying machine learning methods to predict the hospital re-admission within 30 days of total hip arthroplasty and hemiarthroplasty

BackgroundTotal hip arthroplasty (THA) and hemiarthroplasty are common treatments for severe hip joint disease. To predict the probability of re-admission after discharge when patients are hospitalized will support providing appropriate health education and guidance. MethodsThe research aims to use logistic regression (LR), decision trees (DT), random forests (RF), and artificial neural networks (ANN) to establish predictive models and compare their performances on re-admissions within 30 days after THA or hemiarthroplasty. The data of this study includes patient demographics, physiological measurements, disease history, and clinical laboratory test results. ResultsThere were 508 and 309 patients in the THA and hemiarthroplasty studies respectively from September 2016 to December 2018. The accuracies of the four models LR, DT, RF, and ANN in the THA experiment are 94.3%, 93.2%, 97.3%, and 93.9%, respectively. In the hemiarthroplasty experiment, the accuracies of the four models are 92.4%, 86.1%, 94.2%, and 94.8%, respectively. Among these, we found that the RF model has the best sensitivity and ANN model has the best area under the receiver operating characteristic (AUROC) score in both experiments. ConclusionsThe THA experiment confirmed that the performance of the RF model is better than the other models. The key factors affecting the prognosis after THA surgery are creatinine, sodium, anesthesia duration, and dialysis. In the hemiarthroplasty experiment, the ANN model showed more accurate results. Poor kidney function increases the risk of hospital re-admission. This research highlights that RF and ANN model perform well on the hip replacement surgery outcome prediction.

Adverse Events After Total Hip Arthroplasty are not Sufficiently Characterized by 30-Day Follow-Up: A Database Study

BackgroundMany previous studies of total hip arthroplasty (THA) have focused on adverse events occurring within 30 days of surgery. Studies examining 90-day postoperative adverse events have typically not focused on the timing of adverse events within that period. The current study evaluated the rate and timing of adverse events within 90 days of THA. MethodsAdult THA patients between 2010 and 2020 Q3 were identified from a large administrative dataset. Rates and timing of 90-day adverse events were determined. The median, interquartile range, and middle 80% were calculated based on the time of diagnosis for each adverse event. These were also dichotomized as occurring before or after 30 days and predictive factors for later adverse events were determined. ResultsOverall, 81,158 adverse events were noted, of which 56,500 (69.0%) were diagnosed within 30 days of surgery and 25,355 (31.0%) were diagnosed 31-90 days after surgery. The proportion of adverse events occurring 31-90 days after surgery ranged from 6% (transfusion) to 45% (wound dehiscence). Patients experiencing a later adverse event were more likely to be women and to have higher Elixhauser Comorbidity Index (ECI) scores. ConclusionAlmost one-third of adverse events following THA were diagnosed between postoperative days 31 and 90, highlighting the importance of looking beyond 30 days when estimating patients’ risk of postoperative adverse events. These data may inform future research, patient counseling, and prevention strategies.

Neighborhood Socioeconomic Disadvantage Associated With Increased Healthcare Utilization After Total Hip Arthroplasty

BackgroundThe multifaceted effects of socioeconomic status on healthcare outcomes can be difficult to quantify. The Area Deprivation Index (ADI) quantifies a socioeconomic disadvantage with higher scores indicating more disadvantaged groups. The present study aimed to describe the ADI distribution for primary total hip arthroplasty (THA) patients stratified by patient demographics and to characterize the association of ADI with healthcare utilization (discharge disposition and length of stay [LOS]), 90-day emergency department (ED) visits, and 90-day all cause readmissions. MethodsTwo thousand three hundred and ninety one patients who underwent primary elective THA over a 13-month period were included. A multivariable binary logistic regression analysis with outcomes of nonhome discharge, prolonged LOS (>3 days), 90-day ED visits, and 90-day readmission were performed using predictors of ADI, gender, race, smoking status, body mass index, insurance status, and Charlson comorbidity index. Plots of restricted cubic splines were used to graph associations between ADI as a continuous variable and the outcomes of interest using odds ratios. ResultsIn the multivariable regression model, there were statistically significant higher odds of nonhome discharge (OR, 1.82; 95% CI, 1.19-2.77, P = .005) for individuals in the 61-80 ADI quintile as compared to the reference group of 21-40. Individuals in the highest ADI quintile, 81-100, had the greatest odds of nonhome discharge (OR, 2.20; 95% CI, 1.39-3.49, P < .001) and prolonged LOS (OR, 1.91, 95% CI, 1.28-2.84, P = .001). ConclusionsHigher ADI is associated with an increased healthcare utilization within 90 days of THA.

Outcomes of Total Hip Arthroplasty in Patients With Acetabular Protrusio.

Background:Acetabular protrusio (AP) is associated with distorted anatomic landmarks and insufficient bone stock that increases complexity of total hip arthroplasty (THA). This study used a large national database to compare outcomes after THA in patients with and without AP.Methods:The Nationwide Readmissions Database was used to identify patients with and without AP who underwent THA from 2010 to 2014. Primary outcomes analyzed included complications during index hospitalization and within 90 days of THA.Results:Propensity score matching generated 4,395 patients without AP and 4,603 patients with AP. Patients with AP were older (68.1 versus 65.2 years, P < 0.0001), more predominantly women (82.1% versus 55.9%), and had more medical comorbidities as measured by the Elixhauser Comorbidity Index (2.29 versus 1.89, P < 0.0001). Patients with AP had an increased risk of requiring bone graft (odds ratio [OR] = 47.97, 95% confidence interval [CI]: 14.27 to 161.22), receiving a blood transfusion (OR = 1.90, 95% CI: 1.57 to 2.29), and suffering a periprosthetic fracture (OR = 2.56, 95% CI: 1.10 to 5.97) within 90 days of THA. Length and cost of index hospitalization were greater for patients with AP (5.0 versus 4.3 days, P = 0.002; $19,211.88 versus $27,736.30, P < 0.0001).Conclusion:Given the current emphasis on hospital cost optimization, it is important to ensure that patients with AP are managed appropriately. Attention should be placed on comprehensive preoperative planning and postoperative monitoring in this population.

When Can I Drive? Predictors of Returning to Driving After Total Joint Arthroplasty.

A common question by patients considering total joint arthroplasty (TJA) is when can I return to driving. The ability to return to driving has enormous effect on the independence of the patient, ability to return to work, and other activities of daily living. With advances in accelerated rehabilitation protocols, newer studies have questioned the classic teaching of waiting 6 weeks after TJA. The goal of this prospective study was to determine specific patient predictors for return to driving and create individualized models able to estimate return to driving based on patient risk factors for both total knee arthroplasty (TKA) and total hip arthroplasty (THA). From July 2017 to January 2018, 554 primary TKA and 490 primary THA patients were prospectively enrolled to obtain information regarding return to driving. Patients were sent a survey every 2 weeks regarding their return to driving. Additional information regarding vehicle type, transmission, and involvement in motor vehicle accidents was collected. Bivariate analysis was done followed by the creation of a multiple linear regression models to analyze return to driving after TKA and THA. The majority (98.2%, 1,025/1,044) of patients returned to driving within 12 weeks of surgery. On average, patients returned to driving at 4.4 and 3.7 weeks for TKA and THA (P < 0.001), respectively. The rate of motor vehicle accidents was 0.7% (7/1,044) within 12 weeks after surgery with no injuries reported. After multivariate analysis, baseline return to driving began at 10.9 days for TKA and 17.1 days for THA. The following predictors added additional time to return to driving for TJA: not feeling safe to drive, limited range of motion, female sex, limitations due to pain, other limitations, discharge to a rehabilitation facility, right-sided procedures, limited ability to break, preoperative anemia, and preoperative use of a cane. Important predictors identified for return to driving were sex, joint laterality, limited ability to walk or ability to break, and feeling safe. Surgeons should consider these factors when counseling patients on their postoperative expectations regarding driving after TJA.

Factors associated with emergency department presentation after total joint arthroplasty: a population-based retrospective cohort study.

Unplanned visits to the emergency department after total joint arthroplasty are far more common than unplanned readmissions. Our objectives were to characterize the prevalence of presentation to an emergency department for any reason after total joint arthroplasty and to identify risk factors for such visits. Using health administrative databases, we conducted a population-based retrospective cohort study of adults (19-89 yr of age) who received their first primary elective total hip arthroplasty (THA) or total knee arthroplasty (TKA) procedure for arthritis between April 2011 and March 2016 in Ontario. We made univariate comparisons between patients who presented to the emergency department within 30 days of surgery and those who did not in. We determined differences in use of health care services between groups by comparing the change in use in the year before and after surgery between patients who presented to the emergency department and those who did not. We developed logistic regression models for the occurrence of an emergency department visit using backward variable elimination. We identified 42 273 total hip recipients and 70 725 total knee recipients, of whom 5640 (13.3%) and 11 224 (15.9%), respectively, presented to the emergency department within 30 days of surgery. Fewer than 1% of these patients required admission, and nearly half (45%) went to a different institution from where they had their surgery. Among both THA and TKA recipients, patients who presented to the emergency department had a net increase in their median annual health care costs (THA: $501, TKA: $682), compared to a net decrease for the cohort as a whole. Factors associated with increased risk of an emergency visit included increased patient age, male sex, rural residence and various comorbidities. Predictive regression models showed poor discriminative ability for both THA (C-statistic 0.57) and TKA (C-statistic 0.58) recipients. One in 7 patients presented to the emergency department within 30 days of THA or TKA. Some may conceivably have been managed remotely, and very few required readmission. There is a crucial need for strategies to minimize these events.

Medical resource utilization and costs for intraoperative and early postoperative periprosthetic hip fractures following total hip arthroplasty in the medicare population

This study assessed the impact of intraoperative and early postoperative periprosthetic hip fractures (PPHFx) after primary total hip arthroplasty (THA) on health care resource utilization and costs in the Medicare population.This retrospective observational cohort study used health care claims from the United States Centers for Medicare and Medicaid Standard Analytic File (100%) sample. Patients aged 65+ with primary THA between 2010 and 2016 were identified and divided into 3 groups – patients with intraoperative PPHFx, patients with postoperative PPHFx within 90 days of THA, and patients without PPHFx. A multi-level matching technique, using direct and propensity score matching was used. The proportion of patients admitted at least once to skilled nursing facility (SNF), inpatient rehabilitation facility (IRF), and readmission during the 0 to 90 or 0 to 365 day period after THA as well as the total all-cause payments during those periods were compared between patients in PPHFx groups and patients without PPHFx.After dual matching, a total 4460 patients for intraoperative and 2658 patients for postoperative PPHFx analyses were included. Utilization of any 90-day post-acute services was statistically significantly higher among patients in both PPHFx groups versus those without PPHFx: for intraoperative analysis, SNF (41.7% vs 30.8%), IRF (17.7% vs 10.1%), and readmissions (17.6% vs 11.5%); for postoperative analysis, SNF (64.5% vs 28.7%), IRF (22.6% vs 7.2%), and readmissions (92.8% vs 8.8%) (all P < .0001). The mean 90-day total all-cause payments were significantly higher in both intraoperative ($30,114 vs $21,229) and postoperative ($53,669 vs $ 19,817, P < .0001) PPHFx groups versus those without PPHFx. All trends were similar in the 365-day follow up.Patients with intraoperative and early postoperative PPHFx had statistically significantly higher resource utilization and payments than patients without PPHFx after primary THA. The differences observed during the 90-day follow up were continued over the 1-year period as well.

Optimal duration of anticoagulant thromboprophylaxis in total hip arthroplasty: new evidence in 55,540 patients with osteoarthritis from the Nordic Arthroplasty Register Association (NARA) group

Background and purpose — The recommended optimal duration of the thromboprophylaxis treatment in total hip arthroplasty (THA) patients has been a matter of debate for years. We examined the association between short (1–5 days), standard (6–14 days), and extended (≥ 15 days) duration of thromboprophylaxis, with regards to the risk of venous thromboembolism (VTE), major bleeding, and death in unselected THA patients.Patients and methods — We performed a cohort study using prospectively collected data from the population-based hip arthroplasty registries, prescription databases, and patient administrative registries in Denmark and Norway. We included 55,540 primary THA patients with osteoarthritisResults — The 90-day cumulative incidence of VTE was 1.0% for patients with standard treatment (reference), 1.1% for those with short-term treatment (adjusted hazard ratio [aHR] of 1.1, 95% confidence interval (CI) 0.8–1.5) and 1.0% for those with extended treatment (aHR of 0.9, CI 0.8–1.2). The aHRs for major bleeding were 1.1 (CI 0.8–1.6) for short and 0.8 (CI 0.6–1.1) for extended vs. standard treatment. In addition, patients with short and extended treatment had aHRs for death of 1.2 (CI 0.8–1.8) and 0.8 (CI 0.5–1.1) vs. standard treatment, respectively. Patients who started short treatment postoperatively had an aHR for death of 1.8 (CI 1.1–3.1) and absolute risk difference of 0.2%, whereas patients who started short treatment preoperatively had an aHR for death of 0.5 (CI 0.2–1.2) and absolute risk difference of 0.3% compared with patients who had standard treatment with post- and preoperative start, respectively.Interpretation — In routine clinical practice, we observed no overall clinically relevant difference in the risks of VTE and major bleeding within 90 days of THA with respect to thromboprophylaxis duration. However, our data indicate that short-term thromboprophylaxis started postoperatively is associated with increased 90-day mortality. The significance of these data should be explored further.

The Association Between Operative Time and Short-Term Complications in Total Hip Arthroplasty: An Analysis of 89,802 Surgeries

BackgroundIt has been established by previous studies that longer operative times can lead to higher rates of complications and poorer outcomes after total hip arthroplasty (THA). However, these studies were heterogeneous, examined limited complications, and have not provided a clear time after which complications increase. The aims of this study were to (1) assess whether longer operative time increases risk of complications within 30 days of THA, (2) investigate the relationship between operative time and various complications after THA, and (3) identify possible operative times beyond which complication rates increase. MethodsThe National Surgical Quality Improvement Project database was queried to identify 89,802 procedures that were included in the final analysis. The effect of operative time on complications within 30 days was evaluated using multivariate logistic regression models. Spline regression models were created to investigate the relationship between operative time and complications. ResultsLonger operative times were associated with higher risk of readmissions (P < .001), reoperations (P < .001), surgical site infection (P < .001), wound dehiscence (P < .001), renal or systemic complications (P < .001), and blood transfusion (P < .001). A linear relationship was observed between operative time and readmission, reoperation, surgical site infection, and transfusions with increased rate of these complications when the operative time exceeded 75 to 80 minutes. Venous thromboembolic complications had a U-shaped relationship with operative time with the trough around 90 to 100 minutes. ConclusionWhile our findings cannot establish a clear cause and effect relation, they do suggest strong correlation between increased operative time and perioperative complications. Additionally, this study suggests an optimal time of approximately 80 minutes, as a goal for surgeons, that may be associated with less risk of complications following THA.

The effectiveness of ultra-clean air operating theatres in the prevention of deep infection in joint arthroplasty surgery.

Deep infection was identified as a serious complication in the earliest days of total hip arthroplasty. It was identified that airborne contamination in conventional operating theatres was the major contributing factor. As progress was made in improving the engineering of operating theatres, airborne contamination was reduced. Detailed studies were carried out relating airborne contamination to deep infection rates. In a trial conducted by the United Kingdom Medical Research Council (MRC), it was found that the use of ultra-clean air (UCA) operating theatres was associated with a significant reduction in deep infection rates. Deep infection rates were further reduced by the use of a body exhaust system. The MRC trial also included a detailed microbiology study, which confirmed the relationship between airborne contamination and deep infection rates. Recent observational evidence from joint registries has shown that in contemporary practice, infection rates remain a problem, and may be getting worse. Registry observations have also called into question the value of "laminar flow" operating theatres. Observational evidence from joint registries provides very limited evidence on the efficacy of UCA operating theatres. Although there have been some changes in surgical practice in recent years, the conclusions of the MRC trial remain valid, and the use of UCA is essential in preventing deep infection. There is evidence that if UCA operating theatres are not used correctly, they may have poor microbiological performance. Current UCA operating theatres have limitations, and further research is required to update them and improve their microbiological performance in contemporary practice. Cite this article: Bone Joint J 2018;100-B:1264-9.

PMD123 - CLINICAL, PATIENT-REPORTED OUTCOME MEASURES (PROMS) AND ECONOMIC OUTCOMES ASSOCIATED WITH ENHANCED RECOVERY PROGRAMS IN ELECTIVE HIP AND KNEE SURGERY IN EUROPE, THE MIDDLE EAST AND AFRICA: A SYSTEMATIC LITERATURE REVIEW

The purpose of this study was to present the clinical, patient-reported outcome measures (PROMs) and economic outcomes associated with enhanced recovery programs (ERPs) for total hip arthroplasty (THA) and total knee arthroplasty (TKA). A systematic literature review investigating THA and TKA ERPs in Europe, Middle East and Africa, published 2012-2017, was conducted in MEDLINE and other sources. Thirty-four publications were identified; 23 THA and 22 TKA. Of the 34 studies, 21 were prospective and 13 retrospective. Twenty-five studies were multi-arm, 20% had non-ERPs as the comparator. Three THA studies reported clinical outcomes using the Harris Hip Score; one study compared ERP to non-ERP, demonstrating significant improvements at 12 months from baseline of 41.51 and 42.8, respectively. No TKA studies reported clinical outcomes. One of 10 studies reporting PROMs, compared ERP to non-ERP with similar results for TKA and THA. Length of stay (LOS) was improved compared to non-ERPs, by 1.6-2 days for THA and 1.2 days for TKA. ERP readmission rates improved by 0.1-3.5% for THA and by 2% for TKA compared to non-ERPs. One study compared the rate of discharge on the day after surgery, with 30% more discharged in THA ERP group vs non-ERP. ERPs did not compromise patient safety compared to non-ERPs, as indicated by: 0.9% improvement in mortality rate in THA, 2.9% improvement in complication rates, and 11% improvement in transfusion rate in TKA. Patient satisfaction scores were higher in ERPs vs non-ERPs. THA and TKA ERPs were associated with total net cost savings of £401.64 and £76.67 per patient, respectively, compared to non-ERPs. ERPs are intended to optimize patient recovery. Overall, the available evidence suggests that THA and TKA ERPs may improve safety outcomes and reduce LOS, without compromising readmission rates or clinical outcomes. ERPs were also associated with cost savings.