Dislocation Following Anterior and Posterior Total Hip Arthroplasty in the Setting of Spinal Deformity and Stiffness: Evolving Trends Using a High-Risk Protocol at a Single Tertiary Center.

BACKGROUND: Patients who have spinal stiffness and deformity are at the highest risk for dislocation after total hip arthroplasty (THA). Previous reports of this cohort are limited to antero-lateral and postero-lateral (PL) approaches. We investigated the dislocation rate after direct anterior (DA) and PL approach THA with a contemporary high-risk protocol to optimize stability. METHODS: We investigated patients undergoing THA who had preoperative biplanar imaging from January-December 2019. Patients were identified using radiographic criteria of spinal-stiffness (<10-degree change in sacral slope from standing to seated) and deformity (flatback deformity with >10-degree difference in pelvic incidence and lumbar lordosis). There were 367 patients identified (181 DA, 186 PL). The primary outcome was dislocation rate at 2-years postoperatively. Risk-factors for dislocation were evaluated using logistic regressions (significance level of 0.05). RESULTS: There were 6 (1.6%) dislocations in the entire cohort, with low dislocation rates for both DA (0.6%) and PL-THA (2.7%). We observed increased utilization of dual mobility with larger outer head bearings (>38 mm) with PL-THA (34.4 versus 5.0%, P < .01) and conversely increased utilization of 32-mm femoral-heads with DA-THA (39.4 versus 7.0%, P < .001). Surgical approach (PL) was not a significant risk-factor for dislocation (odds ratio: 5.03, P = .15). Patients who had a history of lumbar-fusion had 8-times higher odds for dislocation (OR: 8.20, P = .020). CONCLUSIONS: To the best of our knowledge, this is the largest series to date evaluating DA and PL-THA in the hip-spine 2B-group. Our results demonstrate lower dislocation rate than expected with either surgical approach using a high-risk protocol.

Is Preoperative Weight Reduction in Patients Who Have Body Mass Index ≥ 40 Associated with Lower Complication Rates After Primary Total Hip Arthroplasty?

INTRODUCTION: Given the heightened risk of postoperative complications associated with obesity, delaying total hip arthroplasty (THA) in patients who have a body mass index (BMI) > 40 to maximize pre-operative weight loss has been advocated by professional societies and orthopaedic surgeons. While the benefits of this strategy are not well understood, previous studies have suggested that a 5% reduction in weight or BMI may be associated with reduced complications after THA. METHODS: We identified 613 patients who underwent primary THA in a single institution during a 7-year period, and who had a BMI > 40 recorded 9 to 12 months prior to surgery. Subjects were stratified into three cohorts based on whether their baseline BMI decreased by > 5% (147 patients, 24%), was unchanged (+/-5%) (336 patients, 55%), or increased by > 5% (130 patients, 21%) on the day of surgery. The frequency of 90-day Hip Society and Centers for Medicare & Medicaid Services (CMS) complications was compared between these cohorts. There were significant baseline differences between the cohorts with respect to baseline American Society of Anesthesiologists Class (P < 0.001) and hemoglobin A1C (P = 0.011), which were accounted for in a multivariate regression analysis. RESULTS: In univariate analysis, there was a lower incidence of readmission (P = 0.025) and total complications (P = 0.005) in the increased BMI cohort. The overall complication rate was 18.4% in the decreased BMI cohort, 17.6% in the unchanged cohort, and 6.2% in the increased cohort. However, multivariable regression analysis controlling for potential confounders did not find that preoperative change in BMI was associated with differences in 90-day complications between cohorts (P > 0.05). CONCLUSION: Patients who have a BMI > 40 and achieved a clinically significant (> 5%) BMI reduction prior to THA did not have a lower risk of 90-day complications or readmissions. Thus, delaying THA in these patients to encourage weight loss may result in restricting access to a beneficial surgery without an appreciable safety benefit.

Spine or Hip First? Outcomes in Patients Undergoing Sequential Lumbar Spine or Hip Surgery.

BACKGROUND: Lumbar spine pathology frequently coexists in patients who have hip arthrosis. There is controversy on whether lumbar or hip pathology should be first addressed. The purpose of this study was to evaluate the outcomes of sequential lumbar spine (LSP) or hip arthroplasty (THA). METHODS: Using a large national database from 2010 to 2020, we reviewed the records of 241,279 patients who had concurrent hip arthritis and lumbar spine disease defined as spinal stenosis, lumbar radiculopathy, or degenerative disc disease. During the study period, 6,458 (2.7%) patients with concurrent hip/spine disease underwent sequential operative treatment of either the hip joint or lumbar spine within 2 years. The rates of subsequent surgery in either the hip or the spine, opioid requirements, and rates of hip dislocation were determined and analyzed using compared Chi-squared analyses. RESULTS: Patients undergoing THA first had lower risk of subsequent spinal procedure compared to patients who had spinal procedures first (5.7 versus 23.7%, P < .001). This disparity was maintained up to 5 years (P < .001). Opioid requirements at 1 year were highest in patients who underwent spinal procedures only (836 pills/patient) compared to any other group THA only (566 pills/patient), LSP and then THA (564 pills/patient), THA and LSP (586 pills/patient). Also, THA following LSP was associated with significantly higher rates of dislocation compared to patients undergoing THA first (3.2 versus 1.9%, P < .001). CONCLUSION: Total hip arthroplasty first in patients who have concurrent spine disease was associated with lower risk of subsequent surgery, opioid requirement, and risk of postoperative instability compared to patients having lumbar procedure first.

COVID-19 disruptions to elective postoperative care did not adversely affect early complications or patient reported outcomes of primary TKA.

INTRODUCTION: Elective orthopedic care, including in-person office visits and physical therapy (PT), was halted on March 16, 2020, at a large, urban hospital at the onset of the local COVID-19 surge. Post-discharge care was provided predominantly through a virtual format. The purpose of this study was to assess the impact of postoperative care disruptions on early total knee arthroplasty (TKA) outcomes, specifically 90-day complications, 120-day rate of manipulation under anesthesia (MUA) and 1-year patient-reported outcome measures (PROMs). MATERIALS AND METHODS: Institutional records were queried to identify 624 patients who underwent primary, unilateral TKA for osteoarthritis and who were discharged home between 1/1/20 and 3/15/20. These patients were compared to 558 controls discharged between 1/1/19 and 3/15/2019. Cohort demographics and in-hospital characteristics were equivalent apart from inpatient morphine milligram equivalent (MME) consumption. Patient-reported access to PT (p < 0.001) and post-discharge care (p < 0.001) were worse among study patients. Study patients were prescribed fewer post-discharge PT sessions (19.8 vs. 23.5; p < 0.001) and utilized telehealth more frequently (p < 0.001). Mann-Whitney U, T, Fisher's Exact, and chi-squared tests were used to compare outcomes. RESULTS: Ninety-day CMS complications were lower among study patients (3.5% vs. 5.9%; p = 0.05). Rates of MUA were similar between groups. Study patients reported similar PROMs and marginally inferior VR-12 mental and LEAS functional outcomes at 1 year. CONCLUSION: Disruptions to elective orthopedic care in March 2020 seemed to have had no major consequences on clinical outcomes for TKA patients. Our findings question the usefulness of pre-pandemic post-discharge protocols, which may over-emphasize in-person visits and PT.

Re-initiation of elective total knee arthroplasty with an adapted pathway during the 2020 COVID-19 pandemic was safe and effective.

INTRODUCTION: In June 2020 when elective total knee arthroplasty (TKA) resumed after the initial COVID-19 surge, we adapted our TKA pathway focusing on a shorter hospitalization, increased home discharge, and use of post-discharge telemedicine and telerehabilitation. The purpose of this study was to evaluate if changes in postoperative care affected early TKA outcomes. MATERIALS AND METHODS: Five hundred and fifty-four patients who underwent elective primary unilateral TKA for primary osteoarthritis between June and August 2020 (study group) were matched 1:1 for age, sex, body mass index, and Charlson comorbidity index with control patients who underwent surgery between August and November 2019. Study patients were discharged 25 h earlier on average compared to controls, more frequently on the same-day or postoperative day-1 (24.9% vs. 16.1%; p = 0.001), and more frequently home (97.3% vs. 83.8%; p < 0.001). Study patients used telemedicine (11.7% vs. 0%; p < 0.001) and telerehabilitation (19.7% vs. 2.5%; p < 0.001) at higher rates than controls. Generalized estimating equations, Mann-Whitney U, and Chi-Square tests were used to compare outcomes between groups including unscheduled office visits, ER visits, readmissions, Center for Medicare and Medicaid Services (CMS) complications, manipulation under anesthesia (MUA), and patient-reported outcomes measures (PROMs). RESULTS: Rates of emergency room visits, readmissions, CMS complications, MUA, and improvements in PROMs were similar between cohorts. Study patients experienced higher rates of unscheduled outpatient visits (9.2% vs. 4.9%; p = 0.004), predominantly due to wound complications. CONCLUSIONS: A protocol implemented during the COVID-19 pandemic that leveraged a shortened hospitalization, higher rates of home discharge, and increased use of telemedicine and telerehabilitation was safe and effective.

Preoperative cannabis use does not increase opioid utilization following primary total hip arthroplasty in a propensity matched analysis.

PURPOSE: The recreational and medical use of cannabis is being legalized worldwide. Its use has been linked to an increased risk of developing opioid use disorders. As opioids continue to be prescribed after total hip arthroplasty (THA), the influence that preoperative cannabis use may have on postoperative opioid consumption remains unknown. The purpose of this study was to assess the relationship between preoperative cannabis use and opioid utilization following primary THA. METHODS: We identified all patients over the age of 18 who underwent unilateral, primary THA for a diagnosis of osteoarthritis at a single institution from February 2019 to April 2021. Our cohort was grouped into current cannabis users (within 6 months of surgery) and those who reported never using cannabis. One hundred and fifty-six current users were propensity score matched 1:6 with 936 never users based on age, sex, BMI, history of chronic pain, smoking status, history of anxiety/depression, ASA classification and type of anesthesia. Outcomes included inpatient and postdischarge opioid use in morphine milligram equivalents. RESULTS: Total inpatient opioid utilization, opioids refilled, and total opioids used within 90 postoperative days were similar between the groups. CONCLUSION: In propensity score matched analyses, preoperative cannabis use was not independently associated with an increase in inpatient or outpatient, 90-days opioid consumption following elective THA.

An Overview of Commonly Used Data Sources in Observational Research in Anesthesia.

Anesthesia research using existing databases has drastically expanded over the last decade. The most commonly used data sources in multi-institutional observational research are administrative databases and clinical registries. These databases are powerful tools to address research questions that are difficult to answer with smaller samples or single-institution information. Given that observational database research has established itself as valuable field in anesthesiology, we systematically reviewed publications in 3 high-impact North American anesthesia journals in the past 5 years with the goal to characterize its scope. We identified a wide range of data sources used for anesthesia-related research. Research topics ranged widely spanning questions regarding optimal anesthesia type and analgesic protocols to outcomes and cost of care both on a national and a local level. Researchers should choose their data sources based on various factors such as the population encompassed by the database, ability of the data to adequately address the research question, budget, acceptable limitations, available data analytics resources, and pipeline of follow-up studies.

Robotic Assistance for Posterior Approach Total Hip Arthroplasty Is Associated With Lower Risk of Revision for Dislocation When Compared to Manual Techniques.

BACKGROUND: Robotic-assistance total hip arthroplasty (RA-THA) and computer navigation THA (CN-THA) have been shown to improve accuracy of component positioning compared to manual techniques; however, controversy exists regarding clinical benefit. Moreover, these technologies may expose patients to risks. The purpose of this study is to compare rates of intraoperative fracture and complications requiring reoperation within 1 year for posterior approach RA-THA, CN-THA, and THA with no technology (Manual-THA). METHODS: In total, 13,802 primary, unilateral, elective, posterior approach THAs (1770 RA-THAs, 3155 CN-THAs, and 8877 Manual-THAs) were performed at a single institution between 2016 and 2020. Intraoperative fractures and reoperations within 1 year of the index procedure were identified. Cohorts were balanced using inverse probability of treatment weight based on age, gender, body mass index, femoral cementation, history of spine fusion, and Charlson Comorbidity Index. Logistic regression was performed to create odds ratios for complications. Additional regression analysis for dislocation was performed, adjusting for dual mobility and femoral head size. RESULTS: There were no differences in intraoperative fracture and postoperative complication rates between the groups (P = .521). RA-THA had a 0.3 odds ratio (95% confidence interval 0.1-0.9, P = .046) compared to Manual-THA for reoperation due to dislocation. CN-THA had an odds ratio of 3.0 for reoperation due to dislocation (95% confidence interval 0.8-11.3, P = .114) compared to RA-THA. The remaining complication odds ratios, including those for infection, loosening, dehiscence, and "other" were similar between the groups. CONCLUSION: RA-THA is associated with lower risk of revision for dislocation within 1 year of index surgery, when compared to Manual-THA performed through the posterior approach.

Reduction in hospital length of stay and increased utilization of telemedicine during the "return-to-normal" period of the COVID-19 pandemic does not adversely influence early clinical outcomes in patients undergoing total hip replacement: a case-control study.

BACKGROUND AND PURPOSE: Elective total hip replacement (THR) was halted in our institution during the COVID-19 surge in March 2020. Afterwards, elective THR volume increased with emphasis on fast-track protocols, early discharge, and post-discharge virtual care. We compare early outcomes during this "return-to-normal period" with those of a matched pre-pandemic cohort. PATIENTS AND METHODS: We identified 757 patients undergoing THR from June to August 2020, who were matched 1:1 with a control cohort from June to August 2019. Length of stay (LOS) for the study cohort was lower than the control cohort (31 vs. 45 hours; p < 0.001). The time to first postoperative physical therapy (PT) was shorter in the study cohort (370 vs. 425 minutes; p < 0.001). More patients were discharged home in the study cohort (99% vs. 94%; p < 0.001). Study patients utilized telehealth office and rehabilitation services 14 times more frequently (39% vs. 2.8%; p < 0.001). Outcomes included post-discharge 90-day unscheduled office visits, emergency room (ER) visits, complications, readmissions, and PROMs (HOOS JR, and VR-12 mental/physical). Mann-Whitney U and chi-square tests were used for group comparisons. RESULTS: Rates of 90-day unscheduled outpatient visits (5.0% vs. 7.3%), ER visits (5.0% vs. 4.8%), hospital readmissions (4.0% vs. 2.8%), complications (0.04% vs. 0.03%), and 3-month PROMs were similar between cohorts. There was no 90-day mortality. INTERPRETATION: A reduction in LOS and increased telehealth use for office and rehabilitation visits did not adversely influence 90-day clinical outcomes and PROMs. Our findings lend further support for the utilization of fast-track arthroplasty with augmentation of postoperative care delivery using telemedicine.

The Modern Total Knee Arthroplasty: What to Make of All of These Options?

Total knee arthroplasty (TKA) continues to grow in number each year with over three million procedures anticipated to be performed by 2030. The success and prevalence of the procedure has led to expansion in the types of implants available for surgeons to choose from. Shifts in biomaterials, bearing surfaces, and porous surfaces have occurred recently. It is difficult to find a source to make heads or tails of the available options and what they mean for patient outcomes and satisfaction. This instructional course lecture is focused on helping surgeons decide what to make of all the options available for the modern TKA.

Modifiable Analgesia-/Anesthesia-Related Factors and Risk of Severe Gastrointestinal Complications After Lower Extremity Total Joint Arthroplasty: A Nationwide Analysis.

BACKGROUND: Severe gastrointestinal (GI) complications after elective hip and knee arthroplasty (THA/TKA) are rare. Some of them can be life-threatening and/or require emergency abdominal surgery. We studied the epidemiology of severe GI complications after THA/TKA and associations with anesthesia- and/or analgesia-related factors. METHODS: We included 591,865 THA and 1,139,616 TKA cases (Premier Healthcare claims database; 2006-2016). Main outcomes were GI complications and related emergency surgeries within 30 days after THA/TKA. Anesthesia- and analgesia-related factors were anesthesia type (neuraxial, general), use of peripheral nerve block, patient-controlled analgesia, nonopioid analgesics (acetaminophen, gabapentin/pregabalin, nonsteroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, ketamine), and opioids (in oral morphine equivalents, categorized into low, medium, and high use based on the interquartile range). Mixed-effects models measured associations between anesthesia- and analgesia-related factors and outcomes, which were reported using odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Among THA patients, GI complications were observed in 1.03% (n = 6103), with 0.08% (n = 450) requiring emergency surgery; this was 0.79% (n = 8971) and 0.05% (n = 540), respectively, for TKA patients. After adjustment for relevant covariates (including opioid use), almost all anesthesia-/analgesia-related factors were associated with significantly decreased odds of GI complications, specifically use of cyclooxygenase-2 inhibitors (OR 0.72 CI 0.67-0.76/OR 0.82 CI 0.78-0.86), nonsteroidal anti-inflammatory drugs (OR 0.81 CI 0.77-0.85/OR 0.90 CI 0.86-0.94), and peripheral nerve blocks (OR 0.77 CI 0.69-0.87/OR 0.91 CI 0.85-0.97); all for THA and TKA, respectively (all P < .01). CONCLUSION: Rare, but devastating, acute GI complications (requiring surgery) after THA/TKA may be positively impacted by a variety of modifiable anesthesia-/analgesia-related interventions.

Cost of Care for Patients With Pre-Existing Comorbidities Undergoing Total Joint Arthroplasty: A Retrospective Cohort Study Evaluating Disease-Specific Perioperative Care.

BACKGROUND: Investigations suggest a relationship between increased resource utilization with disease burden and advanced age. However, it remains unknown the degree increased resource utilization is associated with pre-existing conditions, before complications occur. METHODS: This retrospective study identified total hip/knee arthroplasty cases in the Premier Database from 2006 to 2016 (N = 1,613,744), with hospitalization cost as the primary outcome. With a variable combining the conditions and complication, generalized linear models measured associations between condition/complication interaction groups and hospitalization cost. Estimates of percent cost increase by variable were obtained. RESULTS: Across all conditions, an increase in cost ranging from 0.38% to 4.28% was found in the absence of a complication. The "Condition = No, Complication = Yes" group was associated with a range of 11.50%-12.40% increase in average hospitalization cost, and the range was 14.43%-30.85% for the "Condition = Yes, Complication = Yes" group. CONCLUSION: We found that having a high-risk condition without a complication accounted only for a modest hospitalization cost increase.

Defining the Learning Period of a Novel Imageless Navigation System for Posterior Approach Total Hip Arthroplasty: Analysis of Surgical Time and Accuracy.

Introduction: The use of imageless navigation in total hip arthroplasty (THA) is frequently associated with prolonged surgical times, predominantly during the learning period. The purpose of the present study was to characterize the learning period of a novel imageless navigation system, specifically as it related to surgical time and acetabular navigation accuracy. Materials and Methods: This was a retrospective observational study of a consecutive group of 158 patients who underwent primary unilateral THA for osteoarthritis by a team headed by a single surgeon. All procedures used an imageless navigation system to measure acetabular cup inclination and anteversion angles, referencing a generic sagittal and frontal plane. Navigation accuracy was determined by assessing differences between intraoperative inclination and anteversion values and those obtained from standardized 6-week follow-up radiographs. Operative time and navigation accuracy were assessed by plotting moving averages of 7 consecutive cases. The learning period was defined using Mann-Kendall trend analyses, student t-tests and nonlinear regression modeling based on surgical time and navigation accuracy. Alpha error was 0.05. Results: The average surgical time was 67.3 min (SD:9.2) (range 45-95). The average navigation accuracy for inclination was 0.01° (SD:4.2) (range - 10 to 10), and that for anteversion was - 4.9° (SD:3.8) (range - 14 to 5). Average surgical time and navigation accuracy were similar between the first and final cases in the series with no learning period detected. Conclusions: There was no discernible learning period effect on surgical time or system measurement accuracy during the early phases of adoption for this imageless navigation system.

In-hospital surgical site infections after primary hip and knee arthroplasty--incidence and risk factors.

Data of hospitalizations for THA or TKA were analyzed for each year between 1998 and 2007 from the National Inpatient Sample. Demographics, comorbidities, incidence of morbidity and mortality, length of hospital stay (LOS), and overall cost were compared for infected and non-infected patients. Perioperative SSI rates were 0.36% for THA and 0.31% for TKA (412,356 and 784,335 patient entries, respectively). Patients with SSI had a significantly higher overall comorbidity burden, higher perioperative mortality rates, longer length of stay, and higher complication rates. Average cost of in-hospital care was double for SSI versus non-SSI patients. Independent risk factors for perioperative SSI included male gender, minority race, a diagnosis for cancer, liver disease, coagulopathies, fluid and electrolyte disorders, congestive heart failure, and pulmonary circulatory disease. Data relied on coded information and could not differentiate between superficial or deep infection, or capture patients readmitted for SSI, and therefore may have underestimated the true incidence of SSI.

Bilateral total knee arthroplasty guidelines: are we there yet?

The proportion of bilateral total knee replacements (BTKR) to unilateral total knee replacement (UTKR) in the United States is increasing. From 1990 to 2004, the use of BTKRs more than doubled for the entire civilian population and almost tripled among the female population. BTKRs can be performed in a single-stage or a staged procedure. Supporters of single-stage BTKR point out its low complication rates, high patient satisfaction, and cost-effectiveness. Others strongly believe that BTKR performed during the same anesthetic session is associated with increased morbidity and mortality. Single-stage BTKR surgery aims at reducing the exposure to repeated anesthesia, total hospitalization and recovery time, and cost, while maintaining patient safety and reducing the negative clinical and functional outcomes observed in patients undergoing UTKR or staged BTKR. This article presents the current concepts and controversies around BTKR surgery based on the authors' body of research and a review of the literature. We also present our institutional guidelines for candidates for single-stage BTKR.

The Impact of Varying Femoral Head Length on Hip External Rotation During Posterior-approach Total Hip Arthroplasty.

Background: Prior investigations of total hip arthroplasty (THA) have studied the effects of prosthetic femoral head size and stem offset on hip range of motion (ROM), impingement risk, and overall hip stability to optimize the return to activities of daily living. However, the relationship between femoral head length and hip ROM, specifically external rotation (ER), has not been evaluated. The aim of our study was to intraoperatively assess how femoral head length affects hip ROM during a posterior approach THA. Methods: Thirty-two patients undergoing a primary elective THA through a posterior approach were prospectively included. After final femoral stem insertion, femoral head trials were performed using the targeted head length, followed by the shorter (-3.0 to -3.5 mm) and longer (+3.0 to +4.0 mm) head length configurations. At each length, hip ER was measured using an intraoperative goniometer from an imageless navigation system. ER values across the three head lengths were compared using a repeated-measures analysis of variance and paired t-tests. Results: Varying femoral head lengths demonstrated a statically significant and reproducible effect on intraoperative ER range (analysis of variance; P < .001) in each patient. An increased femoral head length (mean 3.4 mm) significantly decreased (P < .001) ER range by 10.8 ± 3.3° while a shortened femoral head length (mean 3.5 mm) significantly increased (P < .001) the ER ROM by 6.0 ± 3.8°. Conclusions: The results of this study demonstrate the sensitivity of hip ROM to incremental changes in femoral head length. As ER is important for activities of daily living, inadvertent lengthening should be avoided.

Patient perceptions of pain management and opioid use prior to hip arthroplasty.

OBJECTIVE: Qualitative assessment investigating patients' perceptions related to opioids including their role in pain control, risks, and handling and disposal prior to undergoing hip replacement. DESIGN: A prospective, cross-sectional survey study. SETTING: Large urban teaching hospital specializing in orthopedic surgery affiliated with Weill Cornell Medical College. PARTICIPANTS: Patients aged 18-80, English-speaking, without recent or chronic opioid use, and planning to undergo primary total hip replacement. A total of 128 patients were enrolled and completed the study. INTERVENTION: A 27-item interview evaluating perceptions on opioid-related -topics. MAIN OUTCOME MEASURES: Responses to interview questions were documented by research assistant. RESULTS: Most patients believe that there should be minimal or no pain with the use of opioids, though they also agree that opioids should be limited to pain that interferes with function or activity. Patients generally appreciate risks of addiction with opioids but are less familiar with risks associated with sleep apnea and sedatives. Minority of patients understand that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) in combination with opioids would effectively reduce pain. Majority of patients were unsure of how to properly store and dispose of opioids. CONCLUSIONS: Qualitative assessment demonstrates that patients may benefit from education and discussion specifically about pain expectations, the role of opioids in treating pain, multimodal analgesia, and proper storage and disposal.

Trends in in-hospital major morbidity and mortality after total joint arthroplasty: United States 1998-2008.

BACKGROUND: The use of total joint arthroplasties is increasing worldwide. In this work we aim to elucidate recent trends in demographics and perioperative outcomes of patients undergoing total hip (THA) or total knee arthroplasty (TKA). METHODS: Data from the US Nationwide Impatient Sample between 1998 and 2008 were gathered for primary THAs and TKAs. Trends in patient age, comorbidity burden, length of hospitalization, frequency of major perioperative complications, and in-hospital mortality were analyzed. In-hospital outcomes were reported as events per 1000 inpatient days to account for changes in length of hospitalization over time. Deyo index, discharge status, and the interaction effect of time and discharge status were included in the adjusted trend analysis for morbidity. RESULTS: Between 1998 and 2008, the average age of patients undergoing TKA and THA decreased by 2 to 3 years (P < 0.001). The average length of stay decreased by approximately 1 day over the time interval studied (P < 0.001). The percentage of patients being discharged home declined from 29.7% to 25.4% after TKA and from 29.3% to 24.2% after THA, in favor of dispositions to long- and short-term care facilities (P < 0.0001). Comorbidity burden as measured by the Deyo comorbidity index increased by 35% and 30% for TKA and THA patients, respectively (P < 0.0001). After TKA, there was an increase in the incidence of the following major complications: pulmonary embolism (coefficient estimate [CE] 0.069; 95% confidence interval [CI], 0.059-0.079; P < 0.0001), sepsis (CE 0.034; 95% CI, 0.014-0.054; P = 0.001), nonmyocardial infarction cardiac complications (CE 0.038; 95% CI, 0.035-0.041; P < 0.0001), and pneumonia (CE 0.039; 95% CI, 0.031-0.047; P < 0.0001). After THA, there was an increase in the incidence of the following major complications: pulmonary embolism (CE 0.031; 95% CI, 0.012-0.049; P = 0.001), sepsis (CE 0.060; 95% CI, 0.039-0.081; P < 0.0001), nonmyocardial infarction cardiac complications (CE 0.040; 95% CI, 0.036-0.043; P < 0.0001), and pneumonia (CE 0.039; 95% CI, 0.029-0.048). In-hospital mortality declined after both TKA (CE -0.059; 95% CI, -0.077 to -0.040; P < 0.0001) and THA (CE -0.068; 95% CI, -0.086 to -0.051; P < 0.0001). CONCLUSION: Between 1998 and 2008, trends show increases in several major in-hospital complications after THA and TKA, including pulmonary embolism, sepsis, nonmyocardial infarction cardiac complications, and pneumonia. Despite the increase in complications, declining in-hospital mortality was noted over this period.