Elective Primary Total Knee Arthroplasty Research Articles

Increased severity of anaemia is associated with 30-day complications following total joint replacement.

The aim of this study was to determine the impact of the severity of anaemia on postoperative complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA). A retrospective cohort study was conducted using the American College of Surgeons National Quality Improvement Program (ACS-NSQIP) database. All patients who underwent primary TKA or THA between January 2012 and December 2017 were identified and stratified based upon hematocrit level. In this analysis, we defined anaemia as packed cell volume (Hct) < 36% for women and < 39% for men, and further stratified anaemia as mild anaemia (Hct 33% to 36% for women, Hct 33% to 39% for men), and moderate to severe (Hct < 33% for both men and women). Univariate and multivariate analyses were used to evaluate the incidence of multiple adverse events within 30 days of arthroplasty. Following adjustment, patients in the THA cohort with moderate to severe anaemia had an increased odds of 6.194 (95% confidence interval (CI) 5.679 to 6.756; p < 0.001) for developing any postoperative complication. Following adjustment, patients in the TKA cohort with moderate to severe anaemia had an increased odds of 5.186 (95% CI 4.811 to 5.590; p < 0.001) for developing any postoperative complication. Among both cohorts, as severity increased, there was an increased risk of postoperative complications. Preoperative anaemia is a risk factor for complications following primary arthroplasty. There is a significant relationship between the severity of anaemia and the odds of postoperative complications. Patients who had moderate to severe anaemia were at increased risk of developing postoperative complications relative to patients with mild anaemia. When considering elective primary THA or TKA in a moderately or severely anaemic patient, surgeons should strongly consider correcting anaemia prior to surgery if possible. Cite this article: Bone Joint J 2020;102-B(4):485-494.

Pulmonary Complications After Hip and Knee Arthroplasty in the United States, 2004-2014.

Pulmonary complications after total joint arthroplasty (TJA) are uncommon but have significant cost impact. Total hip arthroplasty (THA) and total knee arthroplasty (TKA) are 2 of the 5 top procedures requiring inpatient stay within the United States. Subsequent pulmonary complications therefore may impose substantial cost burden for US health care. The purpose of this study was to describe the incidence, risk factors, and clinical implications of pulmonary complications (ie, pneumonia, respiratory failure, pulmonary embolism [PE], and aspiration) after TJA in the United States. The National Inpatient Sample (NIS) was queried for all patients undergoing primary, elective THA and TKA between years 2004 and 2014. Pulmonary complications were defined as the occurrence of pneumonia, respiratory failure, PE, or aspiration after TJA. Demographic and clinical characteristics, inpatient cost, length of stay (LOS), and mortality were compared between patients with and without documented perioperative pulmonary complications. Given the stratified nature of the NIS database, estimates of incidence throughout the United States were made with application of trend weights to observed database frequencies. Analyses of estimated annual complication rates were made using χ tests. Between 2004 and 2014, an estimated 2,679,351 patients underwent elective primary THA. A total of 5,527,205 patients were estimated to have undergone elective primary TKA. THA 1.42% (95% CI, 1.37%-1.47%) and 1.71% (95% CI, 1.66%-1.76%) of TKA procedures were complicated by pneumonia, respiratory failure, PE, or aspiration. During this time, the incidence of perioperative pulmonary complications decreased from 1.57% (95% CI, 1.41%-1.73%) to 1.01% (95% CI, 0.92%-1.10%) after THA (P < .0001) and from 2.03% (95% CI, 1.88%-2.18%) to 1.33% (95% CI, 1.25%-1.42%) after TKA (P < .0001). The adjusted odds ratio (aOR) of experiencing a pulmonary complication was highest among patients with history of significant weight loss (aOR = 4.77; 99.9% CI, 3.97-5.73), fluid/electrolyte disorders (aOR = 3.33; 99.9% CI, 3.11-3.56), congestive heart failure (CHF; aOR = 3.32; 99.9% CI, 3.07-3.58), preexisting paralytic condition (aOR = 2.03; 99.9% CI, 1.57-2.61), and human immunodeficiency virus infection (aOR = 2.00; 99.9% CI, 1.06-3.78). Perioperative pulmonary complications were associated with increased LOS (THA = 3.03 days; 99.9% CI, 2.76-3.31; TKA = +2.72 days; 99.9% CI, 2.58-2.86), increased hospital costs (THA = +9163 US dollars; 99.9% CI, 8054-10,272; TKA = +7257 US dollars; 99.9% CI, 6650-7865), and increased mortality (THA: aOR = 121; 99.9% CI, 78-187; TKA: aOR = 150; 95% CI, 97-233). Despite a decline in overall incidence, perioperative pulmonary complications represent a significant potential source of perioperative morbidity and mortality. The current study highlights potential risk factors for pulmonary complications. Recognition of these factors may help to better stratify patients and mitigate risk of potential complications. This is particularly true of respiratory failure as it is associated with the high increases in resource utilization and mortality in this group.

The Association of Race/Ethnicity and Total Knee Arthroplasty Outcomes in a Universally Insured Population

BackgroundPrior studies have documented racial/ethnic disparities in the United States for total knee arthroplasty (TKA) outcomes. One factor cited as a potential mediator is unequal access to care. We sought to assess whether racial/ethnic disparities persist in a universally insured TKA population. MethodsA US integrated health system’s total joint replacement registry was used to identify elective primary TKA (2000-2016). Racial/ethnic differences in revision and 90-day postoperative events (readmission, emergency department [ED] visit, infection, venous thromboembolism, and mortality) were analyzed using Cox proportional hazard and logistic regression with adjustment for confounders. ResultsOf 129,402 TKA, 68.8% were white, 16.2% were Hispanic, 8.4% were black, and 6.6% were Asian. Compared to white patients, Hispanic patients had lower risks of septic revision (hazard ratio [HR] = 0.69, 95% confidence interval [CI] = 0.57-0.83) and infection (odds ratio [OR] = 0.42, 95% CI = 0.30-0.59), but a higher likelihood of ED visit (OR = 1.28, 95% CI = 1.22-1.34). Black patients had higher risks of aseptic revision (HR = 1.61, 95% CI = 1.42-1.83), readmission (OR = 1.13, 95% CI = 1.02-1.24), and ED visit (OR = 1.31, 95% CI = 1.23-1.39). Asian patients had lower risks of aseptic revision (HR = 0.67, 95% CI = 0.54-0.83), septic revision (HR = 0.78, 95% CI = 0.60-0.99), readmission (OR = 0.89, 95% CI = 0.79-1.00), and venous thromboembolism (OR = 0.59, 95% CI = 0.45-0.78). ConclusionWe observed differences in TKA outcome, even within a universally insured population. While lower risks in some outcomes were observed for Asian and Hispanic patients, the higher risks of aseptic revision and readmission for black patients and ED visit for black and Hispanic patients warrant further research to determine reasons for these findings to mitigate disparities. Level of EvidenceLevel III.

Preoperative Risk Factor Optimization Lowers Hospital Length of Stay and Postoperative Emergency Department Visits in Primary Total Hip and Knee Arthroplasty Patients

BackgroundThe evaluation and management of outcomes risk has become an essential element of a modern total joint replacement program. Our multidisciplinary team designed an evidence-based tool to address modifiable risk factors for adverse outcomes after primary hip and knee arthroplasty surgery. MethodsOur protocols were designed to identify, intervene, and mitigate risk through evidence-based patient optimization. Nurse navigators screened patients preoperatively, identified and treated risk factors, and followed patients for 90 days postoperatively. We compared patients participating in our optimization program (N = 104) to both a historical cohort (N = 193) and a contemporary cohort (N = 166). ResultsRisk factor identification and optimization resulted in lower hospital length of stay (LOS) and postoperative emergency department (ED) visits. Patients in the optimization cohort had a statistically significant decrease in mean LOS as compared to both the historical cohort (2.55 vs 1.81 days, P < .001) and contemporary cohort (2.56 vs 1.81 days, P < .001). Patients in the optimization cohort had a statistically significant decrease in 30- and 90-day ED visits compared to the historical cohort (P30-day = .042, P90-day = .003). When compared with the contemporary cohort, the optimization cohort had a statistically significant decrease in 90-day ED visits (21.08% vs 10.58%, P = .025). The optimization cohort had a statistically significant increase in the percentage of patients discharged home. We noted nonsignificant reductions in readmission rate, transfusion rate, and surgical site infections. ConclusionOptimization of patients before elective primary total hip arthroplasty and total knee arthroplasty reduced average LOS, ED visits, and drove telerehabilitation use. Our results add to the limited body of literature supporting this patient-centered approach.

Experience-optimised fast track improves outcomes and decreases complications in total knee arthroplasty

PurposeThe aim of this study was to describe an advanced total knee arthroplasty (TKA) fast-track programme and determine discharge parameters during hospitalisation, as well as patient satisfaction, outcomes and complications within the first 12 months after surgery. MethodsThis prospective study was based on patients selected consecutively for primary elective TKA, undergoing surgery between 2014 and 2017 in an established fast-track setting.Hospitalisation-related parameters were collected: demographics, body mass index (BMI), surgical time, ischaemia time, haemoglobin values, blood transfusions, length of stay, weight-bearing and stair-climbing time, opioid administration, preoperative and discharge loss of extension and maximum active flexion of the knee, visual analogue scale (VAS), 12-month follow-up satisfaction rate and range of motion, any complications, hospital re-admission and re-operation within the first 12 months. Differences were determined using t-tests. ResultsA total of 704 total knee replacements implanted in 481 patients were included in the study and 223 patients had a bilateral TKA. Their mean age was 69.8 years (range 57–88 years).At the 12-month follow-up, 623 patients (88.5%) reported being satisfied or very satisfied and 15 (2.1%) were dissatisfied with their TKA, mean active flexion and loss of extension were 104.4° and 2.3°, respectively. A total of 15 complications occurred (two percent): five painful knees, three knee stiffness, three haematomas, two infections, one hospital re-admission and one deep venous thrombosis. No cases of pulmonary embolism and death related to surgery were reported. ConclusionThe study reports on an advanced fast-track programme for TKA with a low incidence of surgery- and hospitalisation-related issues and complications and without any severe adverse events during the first year.On average, the fast-track programme had a short length of stay, an early recovery of weight-bearing, knee mobility, pain control and a high satisfaction rate, accompanied with an acceptable 12 month range of motion.

Patients' satisfaction and experiences during elective primary fast-track total hip and knee arthroplasty journey: A qualitative study.

To explore how satisfied patients are with the process of treatment and care and to identify the experiences that patients perceive during elective primary fast-track total hip and knee arthroplasty journey. Greater satisfaction with care has predicted better quality of recovery, and patient experience has been positively associated with patient safety and clinical effectiveness. However, a little is still known about how patients experience their treatment and care. A qualitative interview study. The study was conducted among 20 patients in a single joint replacement centre during 2018. Patient satisfaction was measured using a numerical rating scale. Patients' experiences were identified through qualitative semi-structured interviews which were analysed using an inductive content analysis method. The COREQ checklist was used (Supporting Information). The mean numerical rating scale score for overall satisfaction was 9.0 (SD 1.1) on a scale from 0-10. The patients' experiences were grouped under eight main categories that were derived from the qualitative data in the analysis: (a) patient selection, (b) meeting the Health Care Guarantee, (c) patient flow, (d) postdischarge care, (e) patient counselling, (f) transparency of the journey, (g) communication and (h) feedback. The findings suggest that patients are highly satisfied after an elective primary fast-track total hip and knee arthroplasty. However, closer analysis of the patients' experiences reveals challenges and suggestions on how they could be solved, often involving digital technologies. As the number of total joint arthroplasties grows, patients and their families need to take ever greater responsibility, for their own care from advance preparation to rehabilitation. The findings of the study can be used to organise work, improving patient-clinical communication, fostering engagement and improving patient centredness. In addition, the results pinpoint the issues on how the patient experience could be improved.

Factors associated with the length of stay in total knee arthroplasty patients with the enhanced recovery after surgery model

ObjectivesThe purpose of this study is to identify the factors that influence the length of stay (LOS) in total knee arthroplasty (TKA) patients with an enhanced recovery after surgery (ERAS) program.MethodsInformation from 167 patients (31 males and 136 females, range from 43 years to 88 years old) who underwent the unilateral elective primary TKA from January 2017 to January 2019 were reviewed retrospectively. Factors were analyzed by single-factor variance and multi-factor linear regression.ResultsBy single-factor variance analysis, American Society of Anesthesiologists (ASA) physical status classification system, pre-operation albumin, pre-operation erythrocyte sedimentation rate (ESR), primary and merge diseases, hidden blood loss, and length of operation were correlated with LOS (P < 0.05). Multi-factor linear regression results suggested that gender, ASA class, pre-operation Alb, and pre-operation ESR were associated with LOS (P < 0.05). Moreover, ASA class 3 (B value 4.84), pre-operation Alb < 30 g/L (B value 18.33), and pre-operation ESR > 15 mmol/h (B value 2.21) could increase the LOS, while males (B value − 3.56) had a shortened LOS.ConclusionsOverall, our research found that female, ASA class 3, pre-operation Alb < 30 g/L, and pre-operation ESR > 15 mmol/h could extend LOS in TKA patients with ERAS.

CRISTAL: protocol for a cluster randomised, crossover, non-inferiority trial of aspirin compared to low molecular weight heparin for venous thromboembolism prophylaxis in hip or knee arthroplasty, a registry nested study

IntroductionVenous thromboembolism (VTE) is a serious complication following hip arthroplasty (HA) and knee arthroplasty (KA). This study aims to determine whether aspirin is non-inferior to low molecular weight heparin (LMWH)...

Association of Race/Ethnicity With Hospital Discharge Disposition After Elective Total Knee Arthroplasty

Total knee arthroplasty (TKA) is one of the most common elective procedures performed in adults with end-stage arthritis. Racial disparities in TKA outcomes have been described in the literature. To assess the association of race/ethnicity with discharge disposition and hospital readmission after elective primary TKA and to assess the association of nonhome discharge disposition with hospital readmission risk. This retrospective cohort study used data from the Pennsylvania Health Care Cost Containment Council Database, a large regional database that included demographic data from all discharges of patients who underwent elective primary TKA in 170 nongovernmental acute care hospitals in Pennsylvania from April 1, 2012, to September 30, 2015. Data analyses were conducted from September 29, 2017, to November 29, 2017. Patient race/ethnicity and discharge disposition. Discharge disposition and 90-day hospital readmission. Among 107 768 patients, 7287 (6.8%) were African American, 68 372 (63.4%) were women, 46 420 (43.1%) were younger than 65 years, and 60 636 (56.3%) were insured by Medicare. In multivariable logistic regression, among patients younger than 65 years, African American patients were more likely than white patients to be discharged to inpatient rehabilitation facility (IRF) (adjusted relative risk ratio [aRRR], 2.49 [95% CI, 1.42-4.36]; P = .001) or a skilled nursing facility (SNF) (aRRR, 3.91 [95% CI, 2.17-7.06]; P < .001) and had higher odds of 90-day hospital readmission (adjusted odds ratio [aOR], 1.30 [95% CI, 1.02-1.67]; P = .04). Compared with white patients 65 years or older, African American patients 65 years or older were more likely to be discharged to SNF (aRRR, 3.30 [95% CI, 1.81-6.02]; P < .001). In both age groups, discharge to an IRF (age <65 years: aOR, 3.62 [95% CI, 2.33-5.64]; P < .001; age ≥65 years: aOR, 2.85 [95% CI, 2.25-3.61]; P < .001) or SNF (age <65 years: aOR, 1.91 [95% CI, 1.37-2.65]; P < .001; age ≥65 years: aOR, 1.55 [95% CI, 1.27-1.89]; P < .001) was associated with higher odds of 90-day readmission. This cohort study found that race/ethnicity was associated with higher odds of discharge to an IRF or SNF for postoperative care after primary TKA. Among patients younger than 65 years, African American patients were more likely than white patients to be readmitted to the hospital within 90 days. Discharge to an IRF or SNF for postoperative care and rehabilitation was also associated with a higher risk of readmission to an acute care hospital.

The radiological alignment of components after total knee arthroplasty and its relation to functional outcome

Aim: The main aim of this study is to radiologically assess the components alignment in various planes in total knee replacement and to assess its relationship to the functional outcome using the knee society score. Materials and Methods: This hospital based prospective observational study of 30 patients was conducted in the department of Orthopaedics at Maharaja Agrasen Hospital, New Delhi on patients who underwent elective primary Total Knee Arthroplasty and the period of study being 24 months from June 2016 to May 2018. All patients were assessed clinically and functionally using the Knee Society Score pre and post operatively for a follow up period of 6 months. Results: The mean coronal alignment and rotational alignment of femoral component in our study was 5.87 degrees and 2.99 degrees of external rotation respectively. The mean tibial component coronal and rotational alignment in our study was 90 degrees and 17.77 degrees respectively. The mean preoperative flexion of 81.33 degrees increased to 113.5 degrees postoperatively with a significant p value of

Alternating operating theatre utilization is not associated with differences in clinical or economic outcome measures in primary elective knee arthroplasty.

The practice of alternating operating theatres has long been used to reduce surgeon idle time between cases. However, concerns have been raised as to the safety of this practice. We assessed the payments and outcomes of total knee arthroplasty (TKA) performed during overlapping and nonoverlapping days, also comparing the total number of the surgeon's cases and the total time spent in the operating theatre per day. A retrospective analysis was performed on the Centers for Medicare & Medicaid Services (CMS) Limited Data Set (LDS) on all primary elective TKAs performed at the New England Baptist Hospital between January 2013 and June 2016. Using theatre records, episodes were categorized into days where a surgeon performed overlapping and nonoverlapping lists. Clinical outcomes, economic outcomes, and demographic factors were calculated. A regression model controlling for the patient-specific factors was used to compare groups. Total orthopaedic cases and aggregate time spent operating (time between skin incision and closure) were also compared. A total of 3633 TKAs were performed (1782 on nonoverlapping days; 1851 on overlapping days). There were no differences between the two groups for length of inpatient stay, payments, mortality, emergency room visits, or readmission during the 90-day postoperative period. The overlapping group had 0.74 fewer skilled nursing days (95% confidence interval (CI) -0.26 to -1.22; p < 0.01), and 0.66 more home health visits (95% CI 0.14 to 1.18; p = 0.01) than the nonoverlapping group. On overlapping days, surgeons performed more cases per day (5.01 vs 3.76; p < 0.001) and spent more time operating (484.55 minutes vs 357.17 minutes; p < 0.001) than on nonoverlapping days. The study shows that the practice of alternating operating theatres for TKA has no adverse effect on the clinical outcome or economic utilization variables measured. Furthermore, there is opportunity to increase productivity with alternating theatres as surgeons with overlapping cases perform more cases and spend more time operating per day. Cite this article: Bone Joint J 2019;101-B:1081-1086.

Impact of Bundled Care on Outcomes Following Elective Primary Total Hip or Total Knee Arthroplasty.

Standardized approaches to care and care pathways for patients with joint replacement have been shown to decrease length of stay (LOS), improve patient participation in education, decrease patient anxiety while improving perception of care, and lead to overall efficiency and improved care and outcomes. The purpose of this study was to determine whether implementation of a standardized bundle approach to care influenced the outcomes after total hip or total knee arthroplasty (THA or TKA). A retrospective, quasi-experimental before- and after-design study was used to evaluate the impact of the intervention. Two hospitals implemented a standardized bundle of care for patients undergoing THA or TKA that included preoperative patient education, day of surgery mobilization, and a total joint group physical therapy session (Full Bundle). Data analyses were completed on a convenience sample of 2,200 patients who underwent THA or TKA. Outcomes data measured were LOS, discharge disposition, costs, and readmission rate. Patients receiving the Full Bundle had significant reduction in LOS of roughly 1 day (OR = 1.687, 95% CI [1.578, 1.797]) versus group not receiving all elements (OR = 2.706; 95% CI [2.623, 2.789]). Full Bundle patients were 6 times more likely to be discharged home compared with the Partial Bundle group (OR = 6.01, 95% CI [4.01, 9.03]). Full Bundle group had significantly lower total direct costs, F(1) = 4.06, p = .046, partial η = 0.003. There were no differences in readmission rates between the 2 groups. Patients who had all elements of the THA/TKA bundle had the best outcomes. By improving efficiencies of care through the use of the bundle, the 2 hospitals positively impacted the care and outcomes of THA and TKA patients.

Impact of Resilience on Outcomes of Total Knee Arthroplasty

BackgroundResilience, defined as the ability to bounce back from stress, has been suggested as a predictor of surgical outcomes. The purpose of this study is to examine the relationship between resilience and patient-reported outcomes following primary elective total knee arthroplasty (TKA). We hypothesized that patients exhibiting greater preoperative resilience would report better outcome scores. MethodsA prospective cohort of 153 patients (74 male, 79 female) undergoing primary elective TKA completed questionnaires preoperatively and at 3 and 12 months following their index procedure. The validated Brief Resilience Scale was used to evaluate resilience. Hierarchical multiple linear regression was used to analyze the effect of resilience on KOOS-JR (Knee Injury and Osteoarthritis Outcome Score JR) and PROMIS-10 (Patient-Reported Outcomes Measurement Information System) outcome scores. ResultsAt 12 months, the change in the coefficient of determination (R2) attributable to preoperative resilience was 0.101 (P < .001) and 0.204 (P < .001) for physical and mental health, respectively. Although there was expected improvement in KOOS-JR scores following TKA, the effect of baseline resilience for this outcome was not significant. When evaluating resilience measured concurrently, there was significant correlation with both 3-month and 12-month KOOS-JR and PROMIS-10 outcome scores. ConclusionPreoperative resilience is a significant predictor of overall physical and mental health outcomes at both 3 and 12 months. Greater concurrent resilience predicted better scores across all outcomes. These findings suggest that major elective surgery, like other traumatic events, can cause a change in resilience. Although functional improvements after TKA are expected, those patients who exhibit greater resilience at baseline are more likely to report an improved quality of life.

Association between Allogeneic Blood Transfusion and Wound Infection after Total Hip or Knee Arthroplasty: A Retrospective Case-Control Study.

Background: To assess using a retrospective case control study, whether patients undergoing primary, elective total hip or knee arthroplasty who receive blood transfusion have a higher rate of post-operative infection compared to those who do not.Materials and Methods: Data on elective primary total hip or knee arthroplasty patients, including patient characteristics, co-morbidities, type and duration of surgery, blood transfusion, deep and superficial infection was extracted from the Alberta Bone and Joint Health Institute (ABJHI). Logistic regression analysis was used to compare deep infection and superficial infection in blood-transfused and non-transfused cohorts.Results: Of the 27892 patients identified, 3098 (11.1%) received blood transfusion (TKA 9.7%; THA 13.1%). Overall, the rate of superficial infection (SI) was 0.5% and deep infection (DI) was 1.1%. The infection rates in the transfused cohort were SI 1.0% and DI 1.6%, and in the non-transfused cohort were SI 0.5% and DI 1.0%. The transfused cohort had an increased risk of superficial infection (adjusted odds ratio (OR) 1.9 [95% CI 1.2-2.9, p-value 0.005]) as well as deep infection (adjusted OR 1.6 [95% CI 1.1-2.2, p-value 0.008]).Conclusion: The odds of superficial and deep wound infection are significantly increased in primary, elective total hip and knee arthroplasty patients who receive blood transfusion compared to those who did not. This study can potentially help in reducing periprosthetic hip or knee infections.

Abnormally High, as Well as Low, Preoperative Platelet Counts Correlate With Adverse Outcomes and Readmissions After Elective Total Knee Arthroplasty

BackgroundLaboratory studies are routinely performed as a part of the preoperative workup for a total knee arthroplasty (TKA). The ramifications of abnormal preoperative platelet counts remain uncharacterized in large, multicenter patient populations. MethodsPatients who underwent elective primary TKA were identified in the 2011-2015 National Surgical Quality Improvement Program database. Risk of 30-day postoperative complications was calculated as a function of preoperative platelet counts. Patients were characterized as having a normal platelet count, abnormally low platelet count, and abnormally high platelet count based on relative risk calculations. Univariate and multivariate analyses were performed to associate abnormal platelet counts with patient demographics, operative variables, 30-day postoperative complications, and readmissions. ResultsIn total, 140,073 patients who underwent elective TKA were identified. Using the relative risk threshold of 1.5 for any adverse event, abnormally low and abnormally high platelet count thresholds were set at ≤116,000/mL and ≥492,000/mL, respectively. Multivariate analyses revealed low platelet counts to be associated with higher rates of any, major, and minor adverse events and longer length of stay. Analogously, high platelet counts were associated with higher rates of any and minor adverse events and longer length of stay. ConclusionThe present study employed a large patient sample size and showed that elective TKA patients with abnormally high, as well as low, platelet counts are at increased risk of postoperative adverse outcomes. Focused attention needs to be paid to TKA patients with preoperative abnormal platelet counts for optimization and postoperative care. Level of EvidenceLevel III, retrospective comparative study.

Trends in Length of Stay and 30-Day Complications After Total Knee Arthroplasty: An Analysis From 2006 to 2016

BackgroundHospital length of stay (LOS) is a quality metric and target of recent efforts in the last decade to decrease healthcare costs and postoperative nosocomial complications after total knee arthroplasty (TKA). However, decreasing LOS has raised concerns of possible increased complication and readmission rates. We present a decade-long analysis in trends of LOS and 30-day complication and unplanned readmissions following TKA. MethodsThe National Surgical Quality Improvement Program registry was utilized to identify patients undergoing elective primary TKA between 2006 and 2016. Three cohorts of patients were created based on year of surgery (2006-2009 [N = 7111], 2010-2013 [N = 71,943], and 2014-2016 [N = 142,710]). Patient demographics, perioperative variables, LOS, 30-day postoperative complications, and readmission rates were analyzed between the 3 cohorts using bivariate and multivariate analyses. ResultsLOS decreased significantly over time when the 2006-2009 cohort (3.7 days) was compared to the 2010-2013 cohort (3.3 days, P < .001) and 2014-2016 cohort (3.0 days, P < .001). Similarly, there was a decrease in the rate of total 30-day complications in the 2006-2009 cohort (5.37%) compared to 2010-2013 (3.86%) and 2014-2016 (3.13%, P < .001), with significantly lower rates of deep vein thrombosis, sepsis, and urinary tract infection in the latter cohorts. Decreasing rates of 30-day readmission were also observed in the 2010-2013 cohort (3.63%) compared to 2013-2016 cohort (3.23%, P < .001). ConclusionIn the last decade, there has been a trend toward decreasing LOS after TKA. Despite concerns about early discharge, data from a national registry demonstrated a simultaneous decrease in total 30-day complication and readmission rates. Level of EvidenceIII, Retrospective cohort study.

The Validity of All-Cause 30-Day Readmission Rate as a Hospital Performance Metric After Primary Total Hip and Knee Arthroplasty: A Systematic Review

BackgroundRisk-adjusted all-cause 30-day readmission rate (ACRR) following total hip arthroplasty (THA) and total knee arthroplasty (TKA) is currently used as a metric of hospital performance as part of the Hospital Readmissions Reduction Program. However, the extent to which it is determined by hospital-related factors and is therefore a fair method of determining reimbursement remains unclear. MethodsOur aim was to systematically review the available literature pertaining to whether ACRR is a valid metric of hospital performance after elective primary THA or TKA as determined by (1) its association with other performance metrics, (2) the extent to which variation in ACRR can be explained by between-hospital variation, and (3) the relative importance of hospital-related versus surgeon- or patient-related factors in determining ACRR. The MEDLINE, EMBASE, and Health Management Information Consortium databases were searched from inception to November 2018 and reference lists of selected articles scanned. The final list of articles was determined by consensus. ResultsEight articles were included. Correlation of ACRR with established composite metrics of both outcome and process measures was poor. There was a weak positive correlation between ACRR and mortality. Only 1.5% of the variation in readmission rates for THA and TKA was found to be attributable to hospital-level factors, with patient-related factors such as age and comorbidities having much greater influence. Use of composite outcome metrics, for example, combining readmission and mortality, or considering the “surgical” readmission rate, improved the sensitivity to detect important between-hospital variation. ConclusionThere is insufficient evidence in the current literature to justify the use of ACRR following elective THA and TKA for financially penalizing hospitals. Further work is needed to define what is acceptable variation. The use of a composite metric or surgical readmission rate may improve the ability to detect between-hospital variation.

Clinical Effectiveness of Aspirin as Multimodal Thromboprophylaxis in Primary Total Hip and Knee Arthroplasty: A Review of 6078 Cases

BackgroundVenous thromboembolism is a serious complication after total hip and knee arthroplasty. There is still no consensus regarding the best mode of thromboprophylaxis after lower limb arthroplasty. The aim of this study was to ascertain the efficacy, safety profile, and rate of adverse thromboembolic events of aspirin as extended out-of-hospital pharmacological anticoagulation for elective primary total hip and knee arthroplasty patients and whether these rates were comparable with published data for low-molecular-weight heparin (LMWH). MethodsData were extracted from a prospective hospital-acquired thromboembolism database. The period of study was from January 1, 2013 to December 31, 2016, and a total of 6078 patients were treated with aspirin as extended thromboprophylaxis after primary total hip and knee arthroplasty. ResultsThe primary outcome measure of deep vein thrombosis and pulmonary embolism within 90 days postoperatively was 1.11%. The secondary outcome rates of wound infection, bleeding complications, readmission rate, and mortality were comparable to published results after LMWH use. ConclusionThe results of this study clearly show that aspirin, as part of a multimodal thromboprophylactic regime, is an effective and safe regime in preventing venous thromboembolism with respect to risk of deep vein thrombosis or pulmonary embolism when compared to LMWH. It is a cheaper alternative to LMWH and has associated potential cost savings.

Prospective Validation of a Demographically Based Primary Total Knee Arthroplasty Size Calculator

BackgroundPreoperative planning for total knee arthroplasty (TKA) is essential for streamlining operating room efficiency and reducing costs. Digital templating and patient-specific instrumentation have shown some value in TKA but require additional costs and resources. The purpose of this study was to validate a previously published algorithm that uses only demographic variables to accurately predict TKA tibial and femoral component sizes. MethodsFour hundred seventy-four consecutive patients undergoing elective primary TKA were prospectively enrolled. Four surgeons were included, three of which were unaffiliated with the retrospective cohort study. Patient sex, height, and weight were entered into our published Arthroplasty Size Prediction mobile application. Accuracy of the algorithm was compared with the actual sizes of the implanted femoral and tibial components from 5 different implant systems. Multivariate regression analysis was used to identify independent risk factors for inaccurate outliers for our model. ResultsWhen assessing accuracy to within ±1 size, the accuracies of tibial and femoral components were 87% (412/474) and 76% (360/474). When assessing accuracy to within ±2 sizes of predicted, the tibial accuracy was 97% (461/474), and the femoral accuracy was 95% (450/474). Risk factors for the actual components falling outside of 2 predicted sizes include weight less than 70 kg (odds ratio = 2.47, 95% confidence interval [1.21-5.06], P = .01) and use of an implant system with <2.5 mm incremental changes between femoral sizes (odds ratio = 5.50, 95% confidence interval [3.33-9.11], P < .001). ConclusionsThis prospective series of patients validates a simple algorithm to predict component sizing for TKA with high accuracy based on demographic variables alone. Surgeons can use this algorithm to simplify the preoperative planning process by reducing unnecessary trays, trials, and implant storage, particularly in the community or outpatient setting where resources are limited. Further assessment of components with less than 2.5-mm differences between femoral sizes is required in the future to make this algorithm more applicable worldwide.

Body Mass Index Classification Is Independently Associated with Health-Related Quality of Life after Primary Total Knee Arthroplasty: An Institutional Registry-Based Study.

The purpose of this study was to compare the health-related quality of life (HRQoL) before and after successful total knee arthroplasty (TKA) across World Health Organization (WHO) body mass index (BMI) classifications. Through an institutional registry, patients with end-stage knee osteoarthritis who received elective primary unilateral TKA were identified and categorized based on WHO BMI classification. Age, gender, laterality, year of surgery, and Charlson-Deyo comorbidity index were recorded. The primary outcome was the EQ-5D-3L index and visual analog scale (VAS) at 2 years postoperatively. Inferential statistics and regression analyses were performed to determine associations between BMI classification and HRQoL. EQ-5D-3L index and VAS scores were significantly different across BMI classes, with higher scores in patients with lower BMI at baseline and at 2 years. There was no difference observed for the 2-year change in EQ-VAS scores between groups, but there was a statistically greater increase in index scores for more obese patients. In the regression analyses, there were statistically significant negative effect estimates for EQ-VAS and index scores associated with increasing BMI class, particularly for class III obesity. Higher BMI classification is independently associated with lower HRQoL scores 2 years after uncomplicated primary TKA, although obese patients experienced greater benefits in EQ-5D index scores following TKA. These results detail the relationship between BMI and HRQoL following TKA and suggest that preoperative weight loss may lead to improved outcomes following TKA, but also that obesity, alone, should not be a contraindication to TKA.