Alcohol Withdrawal Is Associated With Worse Outcomes in Patients Undergoing Primary Total Knee or Total Hip Arthroplasty

BackgroundAlcohol withdrawal (AW) syndrome is an independent risk factor for postoperative complications. This study aims to evaluate the influence of AW on perioperative outcomes in patients who underwent primary total knee (TKA) or total hip arthroplasty (THA).MethodsWe used the National Inpatient Sample database to identify patients undergoing TKA/THA from 2003 to 2014. The primary exposure of interest was AW. Multivariable adjusted models were used to evaluate the association of AW with in-hospital medical complications, surgical complications, mortality, cost, and length of stay (LOS) in patients undergoing TKA/THA.ResultsThere were 2,971,539 adult hospitalizations for THAs and 6,367,713 hospitalizations for TKAs included in the present study, among which 0.14% of AW for THA patients and 0.10% of AW for TKA patients. Multivariable adjustment analysis suggested that AW was associated with an increased risk of medical complications (odds ratio [OR] 2.08, 95% confidence interval [CI] 1.79-2.42, P < .0001), surgical complications (OR 1.75, 95% CI 1.51-2.03, P < .0001), and had 4.79 times increase of in-hospital mortality, 26% increase of total cost, and 53% increase of LOS in THA procedures. For TKA procedures, AW was also associated with increased risk of medical complications (OR 3.14, 95% CI 2.78-3.56, P < .0001), surgical complications (OR 2.07, 95% CI 1.82-2.34, P < .0001) and 4.24 times increase of in-hospital mortality, 29% increase of total cost, and 58% increase of LOS after multivariable adjustment.ConclusionAW is associated with increased risk of in-hospital mortality, medical and surgical complications. Proactive surveillance and management of AW may be important in improving outcomes in patients who underwent THA and TKA procedure.     

The Changing Characteristics of Arthroplasty Patients: A Retrospective Cohort Study

BackgroundTotal joint arthroplasty (TJA) is among the most common operations performed worldwide, with global volumes on the rise. It is important to understand if the characteristics of this patient population are changing over time for resource allocation and surgical planning. The purpose of this study is to examine how this patient population has changed between 2003 and 2017.MethodsA retrospective review of a prospective TJA database was conducted. Age, gender, body mass index, comorbidities, American Society of Anesthesiologists class, responsible diagnoses, and comorbidities were compared over 5-year intervals between 2003 and 2017. All patients undergoing primary, elective TJA were included.ResultsOverall, 17,138 TJAs were included. Mean body mass index increased over the study period for total hip arthroplasty (THA; 29.4-30.4 kg/m², P < .0001) and total knee arthroplasty (TKA; 32.0-3.1 kg/m², P < .0001) patients. THA patients were significantly younger in more recent years (68.0-66.8 years old, P = .0026); this trend was not observed among TKA patients. Over the study period, a significantly higher proportion of patients were American Society of Anesthesiologists class III/IV for THA (50.5%-72.3%) and TKA (57.5%-80.7%) (P < .00001). Prevalence of common comorbidities did not change significantly.ConclusionThe key findings of this retrospective analysis of a large prospective database are that patients undergoing TJA are becoming younger and more obese. It is unclear whether patients are becoming more medically complex. These trends paint a concerning picture of a population that is increasingly complex, and may require a greater allocation of resources in the future.Level of EvidenceLevel III, retrospective cohort study.     

Surgeon Reimbursement Unchanged as Hospital Charges and Reimbursements Increase for Total Joint Arthroplasty

BackgroundDespite increasing demands on physicians and hospitals to increase value and reduce unnecessary costs, reimbursement for healthcare services has been under downward pressure for several years. This study aimed to analyze the trend in hospital charges and payments relative to corresponding surgeon charges and payments in a Medicare population for total hip (THA) and knee arthroplasty (TKA).MethodsThe 5% Medicare sample database was used to capture hospital and surgeon charges and payments related to 56,228 patients who underwent primary THA and 117,698 patients who underwent primary TKA between 2005 and 2014. Two values were calculated: (1) the charge multiplier (CM), the ratio of hospital to surgeon charges and (2) the payment multiplier (PM), the ratio of hospital to surgeon payments. Year-to-year variation and regional trends in patient demographics, Charlson Comorbidity Index, length of stay (LOS), CM, and PM were evaluated.ResultsHospital charges were significantly higher than surgeon charges and increased substantially for both THA (CM increased from 8.7 to 11.5, P < .0001) and TKA (CM increased from 7.9 to 11.4, P < .0001). PM followed a similar trend, increasing for both THA and TKA (P < .0001). LOS decreased significantly for both THA and TKA (P < .0001), while Charlson Comorbidity Index remained stable. Both CM (r² = 0.84 THA, 0.90 TKA) and PM (r² = 0.75 THA, 0.84 TKA) were strongly negatively associated with LOS.ConclusionHospital charges and payments relative to surgeon charges and payments have increased substantially for THA and TKA despite stable patient complexity and decreasing LOS.     

Do Patient Engagement Platforms in Total Joint Arthroplasty Improve Patient-Reported Outcomes?

BackgroundWeb-based patient engagement portals are increasing in popularity after total hip and knee arthroplasty (THA and TKA). The literature is mixed regarding patient utilization of these modalities and potential clinical benefit. We sought to determine which demographic factors are associated with increased platform participation and to quantify the impact of a web-based patient portal on patient-reported outcome measures (PROMs).MethodsWe performed a retrospective analysis of consecutive primary THA (n = 554) and TKA (n = 485) at a single academic institution with minimum follow-up of 12 months. Patients were divided into those who opted-in and those who opted-out of portal use. Global health and joint-specific PROMs were collected preoperatively and postoperatively. Linear mixed effects modeling, bivariate analysis, and logistic regression were utilized.ResultsOf the 1039 included patients, 60.6% (336) THA and 62.7% (304) TKA patients enrolled in the portal. Those who opted-in were younger (P < .001, P < .003), had higher body mass index (P = .024, P = .011), and had a higher household income (P < .001, P < .001) in THA and TKA cohorts, respectively. Portal participation in the TKA but not the THA cohort was associated with significant improvement in physical function (P = .017) and joint-specific function (P = .045). For THA patients who opted-in, increased portal logins were associated with more rapid improvement and higher functional scores (P = .013).ConclusionThere is an inherent difference between patients who opt-in to and those who opt-out of web-based portals. Added resources and support provided by portals may translate to improved PROMs for TKA patients but not THA patients.     

High Bundled Payment Costs Following Total Hip and Knee Arthroplasty in African Americans

BackgroundConcerns exist that minorities who utilize more resources in an episode-of-care following total hip (THA) and knee arthroplasty (TKA) may face difficulties with access to quality arthroplasty care in bundled payment programs. The purpose of this study is to determine if African American patients undergoing TKA or THA have higher episode-of-care costs compared to Caucasian patients.MethodsWe queried Medicare claims data for a consecutive series of 7310 primary TKA and THA patients at our institution from 2015 to 2018. We compared patient demographics, comorbidities, readmissions, and 90-day episode-of-care costs between African American and Caucasian patients. A multivariate regression analysis was performed to identify the independent effect of race on episode-of-care costs.ResultsCompared to Caucasians, African Americans were younger, but had higher rates of pulmonary disease and diabetes. African American patients had increased rates of discharge to a rehabilitation facility (20% vs 13%, P < .001), with higher subacute rehabilitation ($1909 vs $1284, P < .001), home health ($819 vs $698, P = .022), post-acute care ($5656 vs $4961, P = .008), and overall 90-day episode-of-care costs ($19,457 vs $18,694, P = .001). When controlling for confounding comorbidities, African American race was associated with higher episode-of-care costs of $440 (P < .001).ConclusionAfrican American patients have increased episode-of-care costs following THA and TKA when compared to Caucasian patients, mainly due to increased rates of home health and rehabilitation utilization. Further study is needed to identify social variables that can help reduce post-acute care resources and prevent reduction in access to arthroplasty care in bundled payment models.     

Life After BPCI: High Quality Total Knee and Hip Arthroplasty Care Can Still Exist Outside of a Bundled Payment Program

BackgroundConcerns regarding target price methodology and financial penalties have led to withdrawal from Medicare bundled payment programs for total hip (THA) and knee arthroplasty (TKA), despite its early successful results. The purpose of this study was to determine whether there was any difference in patient comorbidities and outcomes following our institution’s exit from the Bundled Payments for Care Improvement - Advanced (BPCI-A).MethodsWe reviewed consecutive 2,737 primary TKA and 2,009 primary THA patients following our withdraw from BPCI-A January 1, 2020-March 30, 2021 and compared them to 1,203 TKA and 1,088 THA patients from October 1, 2018-August 2, 2019 enrolled in BPCI-A. We compared patient demographics, comorbidities, discharge disposition, complications, and 90-day readmissions.Multivariate analysis was performed to identify if bundle participation was associated with complications or readmissions.ResultsPost-bundle TKA had shorter length of stay (1.4 vs 1.8 days, P < .001). Both TKA and THA patients were significantly less likely to be discharged to a rehabilitation facility (5.6% vs 19.2%, P < .001 and 6.0% vs 10.0%, P < .001, respectively). Controlling for confounders, post-bundle TKA had lower complications (OR = 0.66, 95% CI 0.45-0.98, P = .037) but no difference in 90-day readmission (OR = 0.80, 95% CI 0.55-1.16, P = .224).ConclusionsSince leaving BPCI-A, we have maintained high quality THA care and improved TKA care with reduced complications and length of stay under a fee-for-service model. Furthermore, we have lowered rehabilitation discharge for both TKA and THA patients. CMS should consider partnering with high performing institutions to develop new models for risk sharing.     

Not all Total Hip and Knee Arthroplasties Are the Same: What Are the Implications in Large Database Studies?

BackgroundThe use of claims databases for research after total hip and knee arthroplasty (THA, TKA) has increased exponentially. These studies rely on accurate coding, and inadvertent inclusion of patients with nonroutine indications may influence results. The purpose of this study was to evaluate the complexity of THA and TKA captured by CPT code and determine if complication rates vary based on the indication.MethodsThe NSQIP database was queried using CPT codes 21730 and 27447 to identify patients undergoing THA and TKA from 2018 to 2019. The surgical indication was classified based on the ICD-10 diagnosis code as routine primary, complex primary, inflammatory, fracture, oncologic, revision, infection, or indeterminant. Patient factors and 30-day complications, readmission, reoperation, and wound complications were compared.ResultsA total of 86,009 THA patients had 703 ICD-10 diagnosis codes and 91.4% were routine primary indications. Complication rates were: routine primary 7.4%, complex primary 11.3%, inflammatory 12.5%, fracture 23.9%, oncologic 32.4%, revision 26.9%, infection 38.7%, and indeterminant 10.3% (P < .0001). 137,500 TKA patients had 552 ICD-10 diagnosis codes and 96.1% were routine primary cases. Complication rates were: routine primary 5.9%, complex primary 8.0%, inflammatory 7.2%, fracture 38.9%, oncologic 32.7%, revision 13.3%, infection 37.7%, and indeterminant 9.6% (P < .0001). Routine primary arthroplasty had significantly lower rates of reoperation, readmission, and wound complications.ConclusionUsing CPT code alone captures 10% of THA and 4% of TKA patients with procedures for nonroutine primary indications. It is essential to recognize identification of patients simply by CPT code has the potential to inadvertently introduce bias, and surgeons should critically assess methods used to define the study populations.     

A Nationwide Analysis on the Impact of Schizophrenia Following Primary Total Knee Arthroplasty: A Matched-Control Analysis of 49,176 Medicare Patients

BackgroundThe influence of schizophrenia on total knee arthroplasty (TKA) is limited in the literature. Therefore, the purpose of this study was to investigate whether patients with schizophrenia undergoing primary TKA have (1) longer in-hospital length of stay (LOS); (2) higher readmission rates; (3) higher medical complications; (4) higher implant-related complications; and (5) higher costs of care compared to controls.MethodsPatients with schizophrenia undergoing primary TKA were identified within the Medicare claims database. The study group was randomly matched in a 1:5 ratio to controls according to age, sex, and medical comorbidities. The query yielded 49,176 patients with (n = 8,196) and without (n = 40,980) schizophrenia undergoing primary TKA. Primary outcomes analyzed included in-hospital LOS, 90-day readmission rates, 90-day medical complications, 2-year implant-related complications, in addition to day of surgery and 90-day costs of care. A P-value less than .01 was considered statistically significant.ResultsSchizophrenia patients had longer in-hospital LOS (3.73 days vs 3.22 days, P < .0001) and had higher incidence and odds ratios (ORs) of readmission rates (18.26 vs 12.07%; OR: 1.58, P < .0001) compared to controls. Schizophrenia patients had higher incidence and odds of medical (3.23 vs 1.10%; OR: 2.99, P < .0001) and implant-related complications (5.92 vs 3.59%; OR: 1.68, P < .0001) and incurred significantly higher day of surgery ($13,300.58 vs $11,681.77, P < .0001) and 90-day costs of care ($18,222.18 vs $14,845.64, P < .0001).ConclusionThis study demonstrates that patients with schizophrenia have longer in-hospital LOS, higher readmission rates, higher complications, and increased costs of care after primary TKA.     

How to Develop a Fair Revision Arthroplasty Bundle? Using Perioperative Complications and Readmissions to Investigate

BackgroundThe next frontier for value-based health care in total joint arthroplasty is revision surgery. Although the disparity in health care utilization between revision procedures compared with primary total hip and total knee arthroplasty (THA/TKA) procedures is recognized, no agreement regarding the risk adjustment necessary to make revision bundles fair to both payors and providers exists. The purpose of this study is to use the risk of perioperative complications and readmissions of patients undergoing revision THA/TKA to establish the foundations of a fair revision arthroplasty bundle.MethodsWe retrospectively evaluated a consecutive series of 484 aseptic THA/TKA revisions performed at our institution over a 12-month period and compared complications, length of stay, reoperations, and 90-day readmissions to a group of 802 consecutive patients undergoing primary THA/TKA.Results169 (34.9%) patients experienced major complications after revision THA/TKA compared with 176 (21.9%) patients undergoing primary THA/TKA (P < .001), (OR 1.91 CI 1.49-2.45, P < .001). Patients undergoing revision TKA were 3.64 times more likely to require hospitalization greater than 3 days (OR 2.59-5.12, CI 95%, P < .001), whereas patients undergoing revision THA were 4.46 times more likely to require hospitalization greater than 3 days (OR 2.89-6.87, CI 95%, P < .001). Revision patients were 3X more likely to have a 90-day readmission and 4X more likely to have a reoperation.ConclusionFor a revision bundle to be fair and widely adopted, either significant financial incentive must be instituted or the latitude given to exclude outliers from the final reconciliation. This must be adjusted to not disincentivize institutions from providing care for failed hip and knee arthroplasties.     

An Analysis of Centers for Medicare & Medicaid Service Payment in Maryland: Can a Global Budget Revenue Model Save Money in Lower Extremity Arthroplasty?

Background

Maryland is the only state utilizing the Global Budget Revenue (GBR) model to reduce costs. The purpose of this study is to evaluate whether the GBR payment model effectively reduced the following: (1) costs of inpatient hospital stays; (2) post-acute care costs; (3) lengths of stay (LOS); (4) readmission rates; and (5) discharge disposition in patients who underwent primary total hip and knee arthroplasty (THA and TKA).

Satisfaction With the Process vs Outcome of Care in Total Hip and Knee Arthroplasty

BackgroundPatient satisfaction, with both process of care and outcome of care, is critical for measuring the quality and value of elective procedures such as arthroplasty. The purpose of this study is to evaluate the correlation between early postoperative satisfaction with the process of care and 2-year satisfaction with the outcome of care after total hip arthroplasty (THA) and total knee arthroplasty (TKA).MethodsWe retrospectively analyzed data from institutional arthroplasty registries. Satisfaction with the outcome of care was measured on a scale of 0-100 by a previously validated questionnaire administered 2 years postoperatively. Patient satisfaction with the process of care was measured by the Press Ganey (PG) inpatient survey, also scored 0-100. We examined the correlation between these 2 measures of satisfaction in patients who underwent primary THA or TKA.ResultsIn total, 721 TKA patients and 760 THA patients underwent surgery and completed both the PG survey and 2-year satisfaction questionnaire. The mean age was 65.1 years with a mean body mass index of 28.8 and 56% were female. The mean PG survey score for the entire cohort was 95.6. The mean 2-year satisfaction score was 90.3. The Spearman correlation coefficient between the PG survey and the 2-year satisfaction survey was 0.23 for TKA patients (P < .001) and 0.13 for THA patients (P < .001).ConclusionWe found a weak correlation between the measurement of satisfaction with the process of care surrounding hip and knee arthroplasty using the PG survey and measurement of satisfaction with the outcome of care after arthroplasty using a validated 2-year satisfaction instrument.     

Hospital Revenue,Cost, and Contribution Margin in Inpatient Versus Outpatient Primary Total Joint Arthroplasty

BackgroundRemoval of primary total knee arthroplasty (TKA) and primary total hip arthroplasty (THA) from the inpatient-only list has financial implications for both patients and institutions. The aim of this study was to evaluate and compare financial parameters between patients designated for inpatient versus outpatient total joint arthroplasty.MethodsWe reviewed all patients who underwent TKA or THA after these procedures were removed from the inpatient-only list. Patients were statistical significance into cohorts based on inpatient or outpatient status, procedure type, and insurance type. This included 5,284 patients, of which 4,279 were designated inpatient while 1,005 were designated outpatient. Patient demographic, perioperative, and financial data including per patient revenues, total and direct costs, and contribution margins (CMs) were collected. Data were compared using t-tests and Chi-squared tests.ResultsAmong Medicare patients receiving THA, CM was 89.1% lower for the inpatient cohort when compared to outpatient (P < .001), although there was no statistical significance difference between cohorts for TKA (P = .501). Among patients covered by Medicaid or Government-managed plans, CM was 120.8% higher for inpatients receiving THA (P < .001) when compared to outpatients and 136.3% higher for inpatients receiving TKA (P < .001).ConclusionOur analyses showed that recent costs associated with inpatient stay inconsistently match or outpace additional revenue, causing CM to vary drastically depending on insurance and procedure type. For Medicare patients receiving THA, inpatient surgery is financially disincentivized leaving this vulnerable patient population at a risk of losing access to care.Level III EvidenceRetrospective Cohort Study.     

A Nurse Navigator Program Is Effective in Reducing Episode-of-Care Costs Following Primary Hip and Knee Arthroplasty

BackgroundAlternative payment models for total hip arthroplasty (THA) and total knee arthroplasty (TKA) have incentivized providers to deliver higher quality care at a lower cost, prompting some institutions to develop formal nurse navigation programs (NNPs). The purpose of this study was to determine whether a NNP for primary THA and TKA resulted in decreased episode-of-care (EOC) costs.MethodsWe reviewed a consecutive series of primary THA and TKA patients from 2015-2016 using claims data from the Centers for Medicare and Medicaid Services and Medicare Advantage patients from a private insurer. Three nurse navigators were hired to guide discharge disposition and home needs. Ninety-day EOC costs were collected before and after implementation of the NNP. To control for confounding variables, we performed a multivariate regression analysis to determine the independent effect of the NNP on EOC costs.ResultsDuring the study period, 5275 patients underwent primary TKA or THA. When compared with patients in the prenavigator group, the NNP group had reduced 90-day EOC costs ($19,116 vs $20,418 for Medicare and $35,378 vs $36,961 for private payer, P < .001 and P < .012, respectively). Controlling for confounding variables in the multivariate analysis, the NNP resulted in a $1575 per Medicare patient (P < .001) and a $1819 per private payer patient cost reduction (P = .005). This translates to a cost savings of at least $5,556,600 per year.ConclusionThe implementation of a NNP resulted in a marked reduction in EOC costs following primary THA and TKA. The cost savings significantly outweighs the added expense of the program. Providers participating in alternative payment models should consider using a NNP to provide quality arthroplasty care at a reduced cost.     

Formal Physical Therapy Following Total Hip and Knee Arthroplasty Incurs Additional Cost Without Improving Outcomes

BackgroundRecent evidence has demonstrated that formal physical therapy (PT) may not be required for most patients undergoing total hip (THA) and knee (TKA) arthroplasty. This study compared the differences in costs and functional outcomes in patients receiving formal PT and those who did not follow primary THA and TKA.MethodsWe queried claims data from a single private insurer identifying patients who underwent primary THA or TKA from 2015 to 2017 in our practice. Demographics, comorbidities, number, and cost of PT visits in a 90-day episode of care were recorded. Outcomes were compared between patients using self-directed home exercises, home PT, outpatient PT, or both home and outpatient PT. A multivariate analysis was performed to identify significant predictors of outcomes.ResultsOf the 2971 patients included in analysis, patients using both services had higher 90-day PT costs (mean $2091, P < .001) than those using home PT alone ($1146), outpatient PT alone ($1356), or no formal PT ($0). Home PT had the greatest cost per visit for both private insurance patients ($177/visit) and Medicare Advantage patients ($157/visit), but patients using both home PT and outpatient PT services had the greatest overall PT cost, $2091 for private insurance and $1891 for Medicare Advantage. Patients who used home PT were at significantly higher risk of both complications (odds ratio = 3.21; 95% confidence interval, 2.1-4.9; P < .001) and readmissions (odds ratio = 3.4; 95% confidence interval, 2.1-5.5; P < .001).ConclusionParticipation in formal PT accounts for up to 8% of the episode of care following THA and TKA. The role of formal PT for most patients should take into account the cost-effectiveness of the intervention.     

Overlapping Surgery Increases Operating Room Efficiency Without Adversely Affecting Outcomes in Total Hip and Knee Arthroplasty

BackgroundSeveral recent studies have demonstrated that overlapping surgeries in total hip (THA) and knee (TKA) arthroplasty do not increase the rates of complications, but whether this practice is cost-effective has yet to be addressed in the literature. The purpose of this study is to determine the effect of overlapping surgery on procedural costs and surgical productivity during THA and TKA.MethodsWe identified all patients undergoing primary THA or TKA from 2015 to 2018 by 18 surgeons at a single orthopedic specialty hospital. Procedural and personnel costs were calculated for each case using a time-driven activity-based costing algorithm. Overlap of surgical time by at least 30 minutes was used to define an overlapping procedure. We compared costs and outcomes between overlapping and nonoverlapping procedures, standardizing all costs to 8-hour time blocks. A multivariate regression analysis was performed to determine independent effect of overlapping procedures on costs and outcomes.ResultsOf the 4786 consecutive procedures, 968 (20.2%) overlapped by at least 30 minutes. Although overlapping rooms increased mean operative time by 8.3 minutes (P < .0001) and operating room personnel costs by $80 per case (<.0001), overlapping surgeons could perform significantly more procedures per 8 hours (7.6 vs 6.4; P < .0001), increasing total 8-hour profit margin by $1215 per procedure. There was no difference in 90-day readmission rate, length of stay, or rates of discharge home between the groups.ConclusionOverlapping noncritical portions of procedures in primary THA and TKA appear to be both a safe practice and an effective strategy.     

Does Age Influence Patient-Reported Outcomes in Unilateral Primary Total Hip and Knee Arthroplasty?

BackgroundTotal hip arthroplasty (THA) and total knee arthroplasty (TKA) are used to treat patients with end-stage arthritis. Previous studies have not demonstrated a consistent relationship between age and patient-reported outcomes. The purpose of this study is to assess the impact of age on patient-reported outcomes after unilateral primary THA or TKA.MethodsA retrospective review of available data in Alberta Bone and Joint Health Institute (ABJHI) Data Repository was performed. We identified 53,498 unilateral primary THA and TKA between April 2011 and 2017. Patients were divided by age into 3 categories: <55, 55-70, and >70. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and EuroQoL 5-dimension (EQ-5D) Canada scores were obtained at presurgery, 3 and 12 months postoperatively.ResultsFor TKA, younger patients had larger improvements in WOMAC scores at 3 and 12 months (P = <.001-.033), and in EQ-5D scores at 3 months (P < .001). When adjusted, patients <55 had lower WOMAC and EQ-5D scores at 3 months postoperatively compared to those 55-70 or >70 (all P < .01). Outcomes at 12 months did not differ between age-groups.For THA, younger patients had larger improvements in WOMAC at 3 months (P = .03). When adjusted, patients <55 had higher WOMAC scores at 12 months postoperatively compared to those 55-70 or >70, and higher EQ-5D scores compared to those 55-70 (all P < .05).ConclusionWhile a multitude of factors go in to quantifying successful THA or TKA, this study suggests that patient age should not be a deterrent when considering the impact of age on patient-reported outcomes.     

Total Hip and Knee Arthroplasties Are Highly Cost-Effective Procedures: The Importance of Duration of Follow-Up

BackgroundTotal hip and knee arthroplasties (THA/TKA) are clinically effective but high cost procedures. The aim of this study is to perform a cost-effectiveness analysis of THA and TKA in the New Zealand (NZ) healthcare system.MethodsData were collected from 713 patients undergoing THA and 520 patients undergoing TKA at our local public hospital. SF-6D utility values were obtained from participants preoperatively and 1-year postoperatively, and deaths and any revision surgeries from patient records and the New Zealand Joint Registry at minimum 8-year follow-up. A continuous-time state-transition simulation model was used to estimate costs and health gains to 15 years. Quality-adjusted life years (QALYs), treatment costs, and incremental cost-effectiveness ratios (ICERs) were calculated to determine cost effectiveness. ICERs below NZ gross domestic product (GDP; NZ$60 600) and 0.5 times GDP per capita were considered “cost effective” and “highly cost effective” respectively.ResultsCumulative health gains were 2.8 QALYs (THA) and 2.3 QALYs (TKA) over 15 years. Cost effectiveness improved from ICERs of NZ$74,400 (THA) and NZ$93,000 (TKA) at 1 year to NZ$6000 (THA) and NZ$7500 (TKA) at 15 years. THA and TKA were cost effective after 2 years and highly cost effective after 3 years. QALY gains and cost effectiveness were greater in patients with worse preoperative functional status and younger age.ConclusionTHA and TKA are highly cost-effective procedures over longer term horizons. Although preoperative status and age were associated with cost effectiveness, both THA and TKA remained cost effective in patients with less severe preoperative scores and older ages.     

Patterns and Costs of 90-Day Readmission for Surgical and Medical Complications Following Total Hip and Knee Arthroplasty

BackgroundUnplanned readmissions following elective total hip (THA) and knee (TKA) arthroplasty as a result of surgical complications likely have different quality improvement targets and cost implications than those for nonsurgical readmissions. We compared payments, timing, and location of unplanned readmissions with Center for Medicare and Medicaid Services (CMS)-defined surgical complications to readmissions without such complications.MethodsWe performed a retrospective analysis on unplanned readmissions within 90 days of discharge following elective primary THA/TKA among Medicare patients discharged between April 2013 and March 2016. We categorized unplanned readmissions into groups with and without CMS-defined complications. We compared the location, timing, and payments for unplanned readmissions between both readmission categories.ResultsAmong THA (N = 23,231) and TKA (N = 43,655) patients with unplanned 90-day readmissions, 27.1% (n = 6307) and 16.4% (n = 7173) had CMS-defined surgical complications, respectively. These readmissions with surgical complications were most commonly at the hospital of index procedure (THA: 84%; TKA: 80%) and within 30 days postdischarge (THA: 73%; TKA: 77%). In comparison, it was significantly less likely for patients without CMS-defined surgical complications to be rehospitalized at the index hospital (THA: 63%; TKA: 63%; P < .001) or within 30 days of discharge (THA: 58%; TKA: 59%; P < .001). Generally, payments associated with 90-day readmissions were higher for THA and TKA patients with CMS-defined complications than without (P < .001 for all).ConclusionReadmissions associated with surgical complications following THA and TKA are more likely to occur at the hospital of index surgery, within 30 days of discharge, and cost more than readmissions without CMS-defined surgical complications, yet they account for only 1 in 5 readmissions.     

Increased Medical Complications,Revisions, In-Hospital Lengths of Stay,and Cost in Patients With Hypogonadism Undergoing Primary Total Knee Arthroplasty

BackgroundResearch regarding the impact of hypogonadism following primary total knee arthroplasty (TKA) is limited. Therefore, the purpose of this study is to investigate whether patients with hypogonadism undergoing primary TKA are at increased odds of (1) medical complications, (2) revisions, (3) in-hospital lengths of stay (LOSs), and (4) cost of care.MethodsA Humana patient population consisting of 8 million lives was retrospectively analyzed from 2007 to 2017 using International Classification of Disease, 9th Revision codes. Patients were filtered by male gender and patients with hypogonadism were matched to controls in a 1:4 ratio according to age and medical comorbidities. The query yielded 8393 patients with (n = 1681) and without (6712) hypogonadism undergoing primary TKA. Primary outcomes analyzed included medical complications, revision rates, in-hospital LOS, and cost of care. Logistic regression analysis was used to calculate odds ratios (OR) of 90-day medical complications and 2-year revisions. Welch’s t-test was used to test for significance in LOS and cost of care between cohorts. A P-value less than .05 was considered statistically significant.ResultsHypogonadal patients undergoing primary TKA were found to have increased incidence and odds (9.45% vs 4.67%; OR 2.12, P < .0001) of developing 90-day medical complications. Hypogonadal patients undergoing primary TKA were found to have a greater incidence and odds (3.99% vs 2.80%; OR 1.89, P < .0001) of 2-year revisions. Hypogonadal patients had a 6.11% longer LOS (3.47 vs 3.27 days, P = .02) compared to controls, and incurred greater 90-day costs ($15,564.31 vs $14,856.69, P = .018) compared to controls.ConclusionThis analysis of over 1600 patients demonstrates that patients with hypogonadism undergoing primary TKA have greater odds of postoperative medical complications, revisions, increased LOS, and cost of care.     

Should the Pareto Principle Be Applied as a Cost Savings Method in Hip and Knee Arthroplasty?

BackgroundUnderstanding the most significant contributions to the cost of completing total hip arthroplasty (THA) and total knee arthroplasty (TKA) is essential to optimize costs and meet funding standards. The objectives of this study are to determine whether cost distribution of THA and TKA follows the Pareto Principle (80/20 rule) and factors predictive of costs that could be modified.MethodsAll inpatient, primary, elective, and unilateral THA and TKA patients from April 2008 to September 2017 were retrospectively reviewed. The Pareto Principle was tested by dividing patients into top 5% cost increments and calculating patient cost category ratio. Relationship between patient-related factors and acute care costs and relationship between cost categories and length of stay (LOS) were examined using multiple regression.ResultsThe Pareto Principle does not apply for THA or TKA patients, with the top 20% of costly patients accounting for approximately 30% of total costs. LOS is the strongest independent driver of costs. Operating room services and supplies accounted for over 50% of total costs but with low variability (coefficient of variation < 0.25). Laboratory and allied health costs had high variability (coefficient of variation > 1.5), but their contribution to total costs was low (from 0.76% to 5.68%).ConclusionTHA and TKA costs do not follow Pareto Principle, concluding that targeting top costly patients is not as effective as focusing on overall patient population. Efforts to decrease overall costs should focus on decreasing the LOS and improving operating room process efficiencies including human resources for supplies and instruments.