In-Hospital Complications and Costs of Simultaneous Bilateral Total Hip Arthroplasty: The Case for Selection and Potential Cost Savings.

Background: Published comparisons between bilateral and unilateral total hip arthroplasty (THA) remain controversial regarding the potential risks and benefits. Our objectives were to compare (1) postoperative complications and (2) resource utilization of patients having simultaneous bilateral THA with patients having unilateral procedures. Methods: The Nationwide Inpatient Sample was used to identify patients undergoing primary elective THA from January 2016 to December 2019. Complications and costs were compared between unilateral and simultaneous bilateral patients. Binary logistic regression analysis controlling demographics, comorbidities, and the primary diagnosis was performed to compare the cohorts of unilateral and bilateral patients. Results: Nine thousand nine hundred fifty-five Bilateral procedures and 785,609 unilateral procedures were identified. Patients with bilateral procedures were at increased risk for many medical complications including gastrointestinal complications (OR: 4.1; 95% CI: 2.4-6.9, P < .01), postoperative blood transfusions (OR: 3.6; 95% CI: 3.3-3.9, P < .01), and pulmonary embolisms (OR: 3.2; 95% CI: 2.0-5.1, P < .01). Patients with bilateral procedures were also at increased risk for joint complications, including periprosthetic fractures (OR: 7.4; 95% CI: 5.2-10.5, P < .01) and other mechanical complications (OR: 27.0; 95% CI: 23-30, P < .01). These patients also incurred higher index hospitalization costs ($25,347 vs $16,757, P < .001) and were discharged more commonly to a rehabilitation facility (17.8% vs 13.4%, P < .001). Conclusions: Bilateral THA are at increased risk of developing postoperative complications despite being younger and having fewer comorbidities on average when compared with unilateral patients. While bilateral patients had a higher index hospitalization cost, the overall cost of one episode of care is lower than two separate hospitalizations.

Varying Complication Rates and Increased Costs in Technology-Assisted Total Hip Arthroplasty Versus Conventional Instrumentation in 1,372,300 Primary Total Hips.

BACKGROUND: The use of technology allows surgeons increased precision in component positioning in total hip arthroplasty (THA). The objective of this study was to compare (1) perioperative complications and (2) resource utilizations between robotic-assisted (RA) and computer-navigated (CN) versus conventional instrumenttaion (CI) THA. METHODS: A retrospective cohort study was performed using a large national database to identify patients undergoing unilateral, primary elective THA from January 1, 2016 to December 31, 2019 using RA, CN, or CI. There were 1,372,300 total patients identified and included RA (29,735), CN (28,480), and CI (1,314,085) THA. Demographics, complications, lengths of stay, dispositions, and costs were compared between the cohorts. Binary logistic regression analyses were performed. RESULTS: The use of RA THA led to lower rates of intraoperative fracture (0.22% versus 0.39%), delirium (0.1% versus 0.2%), postoperative anemia (14.4% versus 16.7%), higher myocardial infarction (0.13% versus 0.08%), renal failure (1.7% versus 1.6%), blood transfusion (2.0% versus 1.9%), and wound dehiscence (0.02% versus 0.01%) compared to CI THA. The use of CN led to lower rates of respiratory complication (0.5% versus 0.8%), renal failure (1.1% versus 1.6%), blood transfusion (1.3% versus 1.9%), and pulmonary embolism (0.02% versus 0.1%) compared to CI THA. Total costs were increased in RA ($17,729 versus $15,977) and CN ($22,529 versus $15,977). Lengths of hospital stay were decreased in RA (1.8 versus 1.9 days) and CN (1.7 versus 1.9 days). CONCLUSIONS: Perioperative complication rates vary in technology-assisted THA, with higher rates in RA THA and lower rates in CN THA, relative to CI THA. Both RA THA and CN THA were associated with more costs, shorter postoperative hospital stays, and higher rates of discharge home compared to CI THA.

Increased Risk of In-Hospital Complications and Costs After Total Hip Arthroplasty for Primary and Secondary Osteonecrosis.

BACKGROUND: An increasing proportion of patients are undergoing total hip arthroplasty (THA) for osteonecrosis (ON). Comorbid conditions and surgical risk factors are known to be greater in ON patients compared with patients who have osteoarthritis (OA) alone. The purpose of our study was to quantify the specific in-hospital complications and resource utilization associated with patients undergoing THA for ON versus OA. METHODS: A large national database was queried to identify patients undergoing primary THA from January 1, 2016 to December 31, 2019. A total of 1,383,880 OA, 21,080 primary ON, and 54,335 secondary ON patients were identified. Demographics, in-hospital complications, costs, lengths of stay, and discharge dispositions for primary and secondary ON cohorts were compared to OA only. Age, race, ethnicity, comorbidities, Medicaid, and income status were controlled with binary logistic regression analyses. RESULTS: The ON patients were often younger, African American or Hispanic, and had more comorbidities. Those undergoing THA for primary and secondary ON had a significantly higher risk of perioperative complications, including myocardial infarction, postoperative blood transfusion, and intraoperative bleeding. Total hospital costs and lengths of stay were significantly higher for both primary ON and secondary ON and both cohorts were less likely to be discharged home. CONCLUSION: While rates of most complications have decreased over recent decades in ON patients undergoing THA, the ON patients still have worse outcomes even when controlling for comorbidity differences. Bundled payment systems and perioperative management strategies for these different patient cohorts should be considered separately.

Inhospital Complications and Costs of Simultaneous Bilateral Total Knee Arthroplasty: The Case for Selection and Potential Cost Savings.

BACKGROUND: Published comparisons between bilateral and unilateral total knee arthroplasties (TKAs) remain biased, as most patients undergoing bilateral TKA are prescreened and healthier than average patients having unilateral procedures. Our objectives were to compare postoperative complications and resource utilization of patients having simultaneous bilateral TKAs with similar patients having unilateral procedures. METHODS: The Nationwide Inpatient Sample (NIS) database was used to identify patients undergoing primary elective TKA from 2002 to 2011. A total of 4,445,263 patients were identified. Of these, 190,783 (4%) were having same-day bilateral procedures. Patients with staged bilateral TKA during the same hospitalization were excluded. Complications and costs were compared to a matched cohort of patients having unilateral procedures. This cohort was matched based on age, gender, and 30 comorbid-defined elements in the NIS. RESULTS: A total of 172,366 (90%) simultaneous bilateral procedures were matched 1:1 to patients with unilateral procedures for the adjusted analysis. Patients with bilateral procedures were at an increased risk for many complications including postoperative anemia (OR: 2.3; 95% CI: 2.2-2.3, P < .001), cardiac (OR: 2.1; 95% CI: 2.0-2.3, P < .001), and inhospital mortality (OR: 3.3; 95% CI: 2.6-4.3). These patients also incurred in higher hospital costs ($19,343 vs $12,852, P < .001) and were discharged more commonly to a rehabilitation facility (70% vs 32%, P < .001). CONCLUSION: Patients undergoing simultaneous bilateral TKA are at an increased risk of developing important postoperative complications and mortality compared with unilateral cases. These data highlight the importance of patient selection and optimization for bilateral TKA and potential cost savings.

Time-Driven Activity-Based Costing in Preoperative Tasks for Total Hip and Knee Arthroplasty.

BACKGROUND: Substantial work in the preoperative phase of total hip arthroplasty (THA) and total knee arthroplasty (TKA) is unaccounted for in current Relative Value Scale Update Committee methodology. A Time-Driven Activity-Based Costing (TDABC) analysis allows for an accurate assessment of the preoperative costs associated with total joint replacement surgery. METHODS: The mean time that clinical staff members spent on preoperative tasks per patient was multiplied by the hourly salary. Clinical staff members included orthopedic surgeons, nurse practitioners or physician assistants, nurses, medical assistants, and surgical coordinators. Mean time spent on preoperative tasks was obtained from the most recent literature. Salaries were obtained from the nationwide database provided by Glassdoor Inc. RESULTS: Total time spent among clinical staff involved in preoperative tasks for each arthroplasty patient was 8.45 hours (2.96-13.94). Total TDABC was calculated to be $348.17 (132.46-562.64). Accounting for preoperative tasks, the TDABC for TKA/THA increases from $13321.5 to $13669.67. Preoperative tasks are composed of 2.6% of total TKA/THA TDABC. In 2020, an estimated $544,189,710 of preoperative TKA/THA work was completed. CONCLUSION: Surgeons, providers, and ancillary staff involved in THA/TKA spend a cumulative preoperative work time of approximately 8.5 hours per patient, which equates to $348.17 that is currently unaccounted for in Relative Value Scale Update Committee methodology.

Total Joint Arthroplasty: A Granular Analysis of Outcomes in the Economically Disadvantaged Patient.

BACKGROUND: Poor patients experience more serious complications and worse outcomes after surgery than higher-income patients. Our objective was to study detailed patient sociodemographic characteristics and preoperative/postoperative patient-oriented outcomes in economically disadvantaged and non-economically disadvantaged primary total joint arthroplasty patients. METHODS: From a consecutive series, 213 economically disadvantaged patients and 1940 non-economically-disadvantaged patients were statistically analyzed. Baseline sociodemographic characteristics and pain visual analog scale, Quality of Well-Being Index 7, Short Form 36, and Western Ontario and McMaster Universities Arthritis Index scores recorded before and after surgery were compared between both groups controlling for baseline differences. Minimum follow-up was 1 year. RESULTS: Economically disadvantaged patients were significantly younger, more likely to be disabled, and had worse preoperative and postoperative scores. CONCLUSION: When compared with non-economically disadvantaged patients, economically disadvantaged patients consistently had lower function and worse quality of life before and after total joint arthroplasty.

Assessment of Damage on a Dual Mobility Acetabular System.

BACKGROUND: Dual mobility designs were introduced to increase stability and reduce the risk of dislocation, both being common reasons for surgical revision after total hip arthroplasty. The in vivo behavior of dual mobility constructs remains unclear, and to our knowledge, no data have been published describing in vivo surface damage to the polyethylene bearing surfaces. METHODS: We used surface damage assessed on the inner and outer polyethylene bearing surfaces in 33 short-term retrieved dual mobility liners as evidence of relative motion at the 2 bearings. A lever out test was performed to determine the force required for dislocation of the cobalt-chromium femoral head from the polyethylene liner. RESULTS: Both bearings showed damage; however, the inner polyethylene bearings had higher damage scores, lower prevalence of remaining machining marks, and higher incidence of concentric wear, all consistent with more motion at the inner polyethylene bearing. The inner polyethylene bearings also had a higher occurrence of embedded titanium debris. The damage sustained in vivo was insufficient to lead to intraprosthetic dislocation in any of the retrieved components. Lever out tests of 12 retrievals had a mean dislocation load of 261 ± 52 N, which was unrelated to the length of implantation. CONCLUSION: Our short-term retrieval data of 33 highly cross-linked polyethylene dual mobility components suggest that although motion occurs at both bearing articulations, the motion of the femoral head against the inner polyethylene bearing dominates. Although damage was not severe enough to lead to intraprosthetic dislocation, failure may occur long term and should be assessed in future studies.

The John Insall Award: Morbid obesity independently impacts complications, mortality, and resource use after TKA.

BACKGROUND: The importance of morbid obesity as a risk factor for complications after total knee arthroplasty (TKA) continues to be debated. Obesity is rarely an isolated diagnosis and tends to cluster with other comorbidities that may independently lead to increased risk and confound outcomes. It is unknown whether morbid obesity independently affects postoperative complications and resource use after TKA. QUESTIONS/PURPOSES: The purpose of this study was to determine whether morbid obesity is an independent risk factor for inpatient postoperative complications, mortality, and increased resource use in patients undergoing primary TKA. METHODS: The Healthcare Cost and Utilization Project Nationwide Inpatient Sample (NIS) database was used to identify patients undergoing primary TKA from October 2005 to December 2008. Morbid obesity (body mass index≥40 kg/m2) was determined using International Classification of Diseases, 9th Revision, Clinical Modification codes. In-hospital postoperative complications, mortality, costs, and disposition for morbidly obese patients were compared with nonobese patients. To control for potential confounders and comorbid conditions, each morbidly obese patient was matched to a nonobese patient using age, sex, and all 28 comorbid-defined elements in the NIS database based on the Elixhauser Comorbidity Index. Of 1,777,068 primary TKAs, 98,410 (5.5%) patients were categorized as morbidly obese. Of these, 90,045 patients (91%) were able to be matched one-to-one to a nonobese patient for the adjusted analysis. RESULTS: Morbidly obese patients had a higher risk of postoperative in-hospital infection (0.24% versus 0.17%; odds ratio [OR], 1.3; 95% confidence interval [CI], 1.1-1.7; p=0.001), wound dehiscence (0.11% versus 0.08%; OR, 1.3; 95% CI, 1.0-1.7; p=0.28), and genitourinary-related complications (0.60% versus 0.44%; OR, 1.3; 95% CI, 1.1-1.5; p<0.001). There was no increase in the prevalence of cardiovascular or thromboembolic-related complications. Morbidly obese patients were at higher risk of in-hospital death after primary TKA compared with nonobese patients (0.08% versus 0.02%; OR, 3.2; 95% CI, 2.0-5.2; p<0.001). Total hospital costs (USD 15,174 versus USD 14,715, p<0.001), length of stay (3.6 days versus 3.5 days, p<0.001), and rate of discharge to a facility (40% versus 30%, p<0.001) were all higher in morbidly obese patients. CONCLUSIONS: Morbid obesity appears to be independently associated with a higher risk for a small number of select in-hospital postoperative complications and mortality after matching for comorbid medical conditions linked to obesity. However, the independent impact of morbid obesity appears to be fairly modest, and morbid obesity did not appear to be an independent risk factor for many systemic complications. Continued research is necessary to identify the influence of associated comorbidities on early postoperative complications in morbidly obese patients after TKA. LEVEL OF EVIDENCE: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Medicaid payer status is associated with in-hospital morbidity and resource utilization following primary total joint arthroplasty.

BACKGROUND: Previous reports suggest that there are major disparities in outcomes following total joint arthroplasty among patients with different payer statuses. The explanation for these differences is largely unknown and may result from confounding variables. The Affordable Care Act expansion of Medicaid coverage in 2014 makes the examination of these disparities particularly relevant. METHODS: The Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) database was used to identify patients who had undergone primary hip or knee arthroplasty from 2002 through 2011. Complications, costs, and length of hospital stay for patients with Medicaid were compared with those for non-Medicaid patients. Each Medicaid patient was matched to a non-Medicaid patient according to age, sex, race, type of total joint arthroplasty, procedure year, hospital characteristics, smoking status, and all twenty-nine comorbidities defined in the NIS-modified Elixhauser comorbidity measure. RESULTS: It was determined that 191,911 patients who underwent total joint arthroplasty had Medicaid payer status (2.8% of the entire total joint arthroplasty population), and 107,335 (56%) of these Medicaid patients were matched one to one to a non-Medicaid patient for all variables for the adjusted analysis. After matching, Medicaid patients were found to have a higher prevalence of postoperative in-hospital infection (odds ratio [OR], 1.7; 95% confidence interval [CI], 1.3 to 2.1), wound dehiscence (OR, 2.2; 95% CI, 1.4 to 3.4), and hematoma or seroma (OR, 1.3; 95% CI, 1.2 to 1.4) but a lower risk of cardiac complications (OR, 0.7; CI, 0.6 to 0.9). The length of the hospital stay was longer, total cost was higher, and discharge to an inpatient facility was more frequent for patients with Medicaid status (p < 0.01). CONCLUSIONS: Compared with non-Medicaid patients, Medicaid patients have a significantly higher risk for certain postoperative in-hospital complications and consume more resources following total joint arthroplasty even when the two groups have been matched for patient-related factors and comorbid conditions commonly associated with low socioeconomic status. Additional work is needed to understand the complex interplay between socioeconomic status and outcomes, to ensure appropriate resources are allocated to maintain access for this patient population, and to develop appropriate risk stratification.

Depression is associated with early postoperative outcomes following total joint arthroplasty: a nationwide database study.

The purpose of this study was to assess the incidence of the diagnosis of depression and determine the impact of this diagnosis on early postoperative outcomes following total joint arthroplasty (TJA). Multivariate analysis of the Nationwide Inpatient Sample database was used to compare the association of depression with inhospital morbidity, mortality, length of stay, and hospital charges following TJA. The rate of diagnosis of depression in the arthroplasty population was 10.0%. Patients with depression were significantly more likely to be white, female, and have Medicaid as a primary payer (all P<0.05). Depression was associated with a greater risk of post-operative psychosis (OR = 1.74), anemia (OR = 1.14), infection (OR = 1.33), and pulmonary embolism (OR 1.20), and a lower risk of cardiac (OR = 0.93) and gastrointestinal complications (OR = 0.80). Depression was not associated with in-hospital mortality. Depression appears to impact early postoperative morbidity after TJA, a finding which is important for patient counseling and risk adjustment.

Postdischarge costs in arthroplasty surgery.

Postdischarge costs associated with primary arthroplasty surgeries have received limited attention in the literature. Our objective was to identify the costs incurred after discharge in primary arthroplasty and to estimate annual postdischarge expenditures in the United States. A cohort of 136 patients who underwent primary arthroplasty was studied. Comprehensive rehabilitation unit (CRU) and home care (HC) costs were obtained. The National Hospital Discharge Survey 2003 data were used to model the national discharge cost estimates. Local patient-oriented outcome was also compared in the patients discharged to CRU vs HC. Total costs were significantly lower in patients discharged directly to home vs those sent to the CRU and who subsequently received HC ($2405 vs $13435, P < .001); both patient groups experienced similar quality of life improvements. An estimated $3.2 billion is spent annually on postsurgical rehabilitation after arthroplasty. Postdischarge costs are significantly higher for patients going to a CRU vs those discharged home; yet, both groups had comparable short-term outcomes.