Go Big or Go Home: Obesity and Total Joint Arthroplasty.

Obesity is highly prevalent, and it is expected to grow considerably in the United States. The association between obesity and an increased risk of complications following total joint arthroplasty (TJA) is widely accepted. Many believe that patients with body mass index (BMI) >40 have complications rates that may outweigh the benefits of surgery and should consider delaying it. However, the current literature on obesity and outcomes following TJA is observational, very heterogeneous, and full of confounding variables. BMI in isolation has several flaws and recent literature suggests shifting from an exclusively BMI <40 cutoff to considering 5 to 10% preoperative weight loss. BMI cutoffs to TJA may also restrict access to care to our most vulnerable, marginalized populations. Moreover, only roughly 20% of patients instructed to lose weight for surgery are successful and the practice of demanding mandatory weight loss needs to be reconsidered until convincing evidence exists that supports risk reduction as a result of preoperative weight loss. Obese patients can benefit greatly from this life-changing procedure. When addressing the potential difficulties and by optimizing preoperative assessment and intraoperative management, the surgery can be conducted safely. A multidisciplinary patient-centered approach with patient engagement, shared decision-making, and informed consent is recommended.

Catastrophic Early Failure and Fragmentation of a Modern Moderately Cross-linked Polyethylene Acetabular Liner.

A 60-year-old man who underwent uncomplicated staged bilateral total hip arthroplasty for femoral head osteonecrosis presented with mechanical catching of his left total hip arthroplasty 3 years after index surgery. Radiographs revealed eccentricity of the left femoral head, concerning the failure of a modern moderately cross-linked polyethylene liner. Catastrophic polyethylene liner failure with significant wear, fragmentation, and femoral head abrasion was noted during revision surgery. The original liner and head were replaced, and the patient has exhibited no complications, pain, or difficulty ambulating 6 months postoperatively. This report highlights one potential novel mechanism for the failure of the Exactech Connexion GXL liner (Exactech Inc., Gainesville, FL), an implant recently reported to have a higher-than-expected failure rate, potentially due to insufficient packaging and increased oxidative processes.

The use of causal language and inferences in observational shoulder arthroplasty database studies.

BACKGROUND: Over the last few decades, several databases and clinical registries have been used to generate studies for orthopedic surgery research including shoulder arthroplasty. Observational database studies present data that are best used to provide information regarding associations between variables but is unable to prove causation. Yet, there remains a tendency for authors to use causal language and conclusive statements in published shoulder arthroplasty literature using such databases. METHODS: We systematically identified administrative database and registry studies on shoulder arthroplasty in 5 orthopedic journals from January 2020 to December 2021. Papers were independently graded by 2 reviewers for the presence, absence, or inconsistent use of causal language throughout the publication. χ2 analyses were conducted to determine the relationship between causality language and article characteristics including the journal of publication. RESULTS: There were 65 eligible articles. According to the reviewers, 67.7% of titles and abstracts were either consistently causal or inconsistently causal in language and inference. On reviewing the full text, 69.2% were found to contain some degree of causal language (38.5% consistently causal, 30.8% inconsistently causal). There were no statistically significant associations between the journal and title and abstract final grading (P = .863) or the journal and full-text grading (P = .726). CONCLUSION: The use of causal language remains highly prevalent in observational database studies related to shoulder arthroplasty. Understanding the limitations of observational database studies is paramount for accurate interpretation of these publications.

Increased Dislocation Rates After Total Hip Arthroplasty in Patients With Prior Isolated Sacroiliac Joint Arthrodesis.

BACKGROUND: While stiffness of the lumbosacral spine is a known predictor of instability following total hip arthroplasty (THA), little is known about the medical- and surgical-related outcomes following THA in patients who have prior isolated sacroiliac (SI) joint arthrodesis. METHODS: 197 patients who had a history of isolated SI joint arthrodesis who subsequently underwent elective primary THA for a diagnosis of osteoarthritis (THA-SI) from 2015 to 2021 were identified in a national administrative database. Using propensity score matching and logistic regression analyses, this cohort was compared to two groups of patients: patients who did not have any history of lumbar or SI arthrodesis and patients undergoing primary THA who had a history of lumbar arthrodesis without extension into the SI joint (THA-LF). RESULTS: The THA-SI group had a significantly higher incidence of dislocation (odds ratio 2.06, 95% confidence interval 1.04-4.04, P = .037) with no increased incidence of medical complications or other surgical complications when compared to patients without a history of SI or lumbar arthrodesis. There were no significant differences in any complications in THA-SI patients when compared to THA-LF patients. CONCLUSION: Patients who had prior isolated SI joint arthrodesis undergoing primary THA demonstrated a two-fold increased incidence of dislocation when compared to those who did not have prior SI arthrodesis, although the risk of complications in this population was similar to that observed in patients who had prior isolated lumbar spine arthrodesis.

The Impact of Robotic-Assisted Total Knee Arthroplasty on Resident Training.

BACKGROUND: As robotic-assisted total knee replacement (rTKA) continues to gain popularity, the impact of this technology on resident education remains unknown. The purpose of this study was to describe trainee experience and perceptions of rTKA and its effect on surgical training. METHODS: Two hundred and twenty two senior orthopaedic residents attending a national board review course completed a 17-question survey regarding their experience and perceptions regarding rTKA. Mean and standard deviations were calculated for Likert scale questions, and bivariate analyses were utilized to compare answer groups. RESULTS: Seventy percent of respondents reported exposure to rTKA during their training. Of those with robotic exposure, 20% reported that greater than half of their TKA experience involved robotics. Only 29% percent agreed that robotics improved outcomes, whereas 21% disagreed and the remainder were unsure. Over half of respondents agreed that robotics are used primarily for marketing purposes. Of those who trained with rTKA, 45% percent believed that robotics improved their understanding of the surgical procedure; however, 25% felt robotics negatively compromised their training with traditional instrumentation. Higher robotic case exposure (P = .001) and attending an industry-sponsored course (P = .02) was associated with the belief that robotics improved outcomes. Robotic case volume and percentage was associated with the belief that robotics improved understanding of the surgical procedure, however, it also was associated with reduced comfort performing traditional knee arthroplasty (P = .001). CONCLUSION: Current resident training experience varies greatly within the United States with regards to rTKA. While exposure to rTKA may be beneficial for a well-rounded surgical education, over-exposure likely results in decreased comfort with traditional instrumentation.

How to Create an Orthopaedic Arthroplasty Administrative Database Project: A Step-by-Step Guide Part I: Study Design.

BACKGROUND: Use of clinical and administrative databases in orthopaedic surgery research has grown substantially in recent years. It is estimated that approximately 10% of all published lower extremity arthroplasty research have been database studies. The aim of this review is to serve as a guide on how to (1) design, (2) execute, and (3) publish an orthopaedic administrative database arthroplasty project. METHODS: In part I, we discuss how to develop a research question and choose a database (when databases should/should not be used), detailing advantages/disadvantages of those most commonly used. To date, the most commonly published databases in orthopaedic research have been the National Inpatient Sample, Medicare, National Surgical Quality Improvement Program, and those provided by PearlDiver. General advantages of most database studies include accessibility, affordability compared to prospective research studies, ease of use, large sample sizes, and the ability to identify trends and aggregate outcomes of multiple health care systems/providers. RESULTS: Disadvantages of most databases include their retrospective observational nature, limitations of procedural/billing coding, relatively short follow-up, limited ability to control for confounding variables, and lack of functional/patient-reported outcomes. CONCLUSION: Although this study is not all-encompassing, we hope it will serve as a starting point for those interested in conducting and critically reviewing lower extremity arthroplasty database studies.

How to Create an Orthopaedic Arthroplasty Database Project: A Step-by-Step Guide Part II: Study Execution.

In recent years, the use of national databases in orthopaedic surgery research has grown substantially with database studies comprising an estimated ∼10% of all published lower extremity arthroplasty research. The aim of this review is to serve as a guide on how to: (1) design; (2) execute; and (3) publish an orthopaedic database arthroplasty project. In part II, we discuss how to collect data, propose a novel checklist/standards for presenting orthopaedic database information (SOPOD), discuss methods for appropriate data interpretation/analysis, and summarize how to convert findings to a manuscript (providing a previously published example study). Data collection can be divided into two stages: baseline patient demographics and primary/secondary outcomes of interest. Our proposed SOPOD is more orthopaedic-centered and builds upon previous standards for observational studies from the EQUATOR network. There are a host of statistical methods available to analyze data to compare baseline demographics, primary/secondary outcomes, and reduce type 1 errors seen in large datasets. When drafting a manuscript, it is important to consider and discuss the limitations of database studies, including their retrospective nature, issues with coding/billing, differences in statistical versus clinical significance (or relevance), lack of surgery details (approach, laterality, and implants), and limited sampling or follow-up. We hope this paper will serve as a starting point for those interested in conducting lower extremity arthroplasty database studies.

Total Hip Arthroplasty in Patients Who Have Respiratory Disease Who use Supplemental Home Oxygen.

BACKGROUND: The purpose of this study is to investigate the association between supplemental home oxygen prior to surgery and both medical and surgical complications after primary elective total hip arthroplasty (THA) in patients who have respiratory disease (RD). METHODS: The Mariner database was used to identify patients who have RD who received primary elective THA from 2010 to 2020. The THA patient cohorts consisted of 20,872 patients who had RD prescribed home oxygen and 69,520 patients who had RD without home oxygen. For patients who had a diagnosis of RD and were prescribed supplemental home oxygen (O2) and those who were not, the rates of postoperative medical and surgical complications, hospital readmissions, and emergency room visits were determined. Reimbursements and lengths of stay were also determined. Logistic regression analyses were utilized to compare both cohorts to matched cohorts without RD, as well as to each other directly. RESULTS: In comparison to the matched control group, the RD with home oxygen group had a significantly higher rate of pneumonia (odds ratio [OR] 4.27, P < .0001), pulmonary embolism (OR 1.81, P < .0001), periprosthetic joint infection (OR 1.21, P < .0001), and periprosthetic fracture (OR 1.81, P = .001). The RD with home oxygen cohort also had a significantly higher incidence of pneumonia (OR 2.16, P < .0001), periprosthetic joint infection (OR 1.38, P < .0001), and periprosthetic fracture (OR 1.24, P = .009) compared to RD patients who did not have home oxygen. CONCLUSION: Supplemental home oxygen use prior to surgery is associated with a significantly higher risk of postoperative medical and surgical complications after elective THA.

Optimizing Use of Large Databases in Joint Arthroplasty and Orthopaedics.

The potential users of "big data" need to consider many factors when choosing whether to use a large observational database for their research question and, if so, which database is the best fit for the scientific question. The first section of this paper, written by Dr. James A. Browne, provides a framework (who, what, where, when, and why?) to assess the critical elements that are included in a large database, which allows the user to determine if interrogation of the data is likely to answer the research question. The next section of this paper, written by Dr. Bryan Springer, focuses on the importance of having an a priori research question before deciding the best data source to answer the question; it also elaborates on the differences between administrative databases and clinical databases. The final section of the paper, written by Dr. Kurt P. Spindler, reviews the concepts of hypothesis-generating and hypothesis-testing studies and discusses in detail the differences, strengths, limitations, and appropriate uses of observational data versus randomized controlled trials.

Use of Supplemental Home Oxygen is Associated With Early Postoperative Complications Following Total Knee Arthroplasty.

BACKGROUND: The objective of this study is to evaluate preoperative supplemental home oxygen use as a potential risk factor for both medical and surgical complications following primary elective total knee arthroplasty (TKA) in patients who have respiratory disease (RD). METHODS: Patients with a diagnosis of RD who underwent elective TKA from 2010 to 2020 were identified using a national database. The rates of postoperative medical and surgical complications, hospital readmissions, and emergency room visits were calculated for RD patients who used supplemental home oxygen and those who did not. Additionally, reimbursements and lengths of stay were determined. Both cohorts were then compared to matched cohorts who did not have RD using logistic regression analyses. RESULTS: A total of 41,418 patients who underwent TKA with RD on home oxygen and 138,635 patients who had RD without home oxygen use were compared with matched cohorts. The RD cohort with home oxygen use had a significantly higher incidence of periprosthetic joint infection (5.78% versus 2.69%, odds ratio [OR] 1.42, P < .0001), pneumonia (3.95% versus 0.69%, OR 4.44, P < .0001), venous thromboembolism (3.17% versus 2.10%, OR 1.12, P = .007), and periprosthetic fracture (0.82% versus 0.34%, OR 1.72, P < .0001) compared to the matched control cohort. Additionally, the RD with home oxygen cohort had a significantly higher incidence of periprosthetic joint infection (5.78% versus 3.77%, OR 1.15, P < .0001), pneumonia (3.95% versus 1.63%, OR 1.99, P < .0001), and several other medical complications compared to RD patients without home oxygen use. CONCLUSION: Preoperative supplemental home oxygen use is associated with significantly increased risk of postoperative surgical and medical complications following elective TKA. This finding can help guide risk assessment and the informed consent process prior to surgery.

Self-Reported Health of Severely Obese US Adults With Osteoarthritis.

BACKGROUND: Severe obesity is associated with complications following arthroplasty, leading surgeons to increasingly counsel patients regarding weight loss. For patients seeking arthroplasty, learning that severe obesity may be a relative contraindication to surgery can create a challenging clinical interaction. We sought to describe the self-reported health of United States (US) adults who had severe obesity and osteoarthritis (OA) to better understand patient perspectives. METHODS: The National Health and Nutrition Examination Survey, a nationally representative sample of the US population, was used to identify adult participants who had a body mass index (BMI) over 35 and an OA diagnosis. In total, 889 participants representing a US population of 9,604,722 were included. Self-reported health was dichotomized as poor to fair versus good to excellent. Analyses were weighted to produce national estimates. Associations between obesity severity and patient characteristics with self-reported health were assessed. RESULTS: Of US adults with a BMI over 35 and OA diagnosis, 64% rated their health as good or better. For adults who had a BMI over 45, 55% still reported their health as good or better. The strongest predictors of self-reported health were measures of physical functioning. Only 37% of participants who had much difficulty walking a quarter mile rated their health as good or better compared to 86% without difficulty (P < .001). CONCLUSION: Approximately two-thirds of patients who have severe obesity and OA do not perceive their health as compromised and consider decreased physical function as the primary driver of decreased health. This suggests that counseling about the association between obesity and overall health may improve shared decision making and that patient satisfaction metrics may be difficult to interpret in these clinical situations.

The Timing of Preoperative Urinary Tract Infection Influences the Risk of Prosthetic Joint Infection Following Primary Total Hip and Knee Arthroplasty.

BACKGROUND: The importance of preoperative urinary tract infection (UTI) in total hip and knee arthroplasty (THA and TKA) is controversial. The purpose of this study was to investigate the timing of preoperative UTI diagnosis and association with prosthetic joint infection (PJI) and determine if antibiotics impact this risk. METHODS: A national database was used to analyze patients undergoing THA and TKA diagnosed with a preoperative UTI. Timing of diagnosis was categorized by 1-week intervals prior to surgery. Matched cohorts without UTI were collected, and PJI rates within 2 years of surgery were compared. Patients who received antibiotic prescriptions were identified and compared to no prescription. RESULTS: Preoperative UTI within 1 week of TKA was associated with higher rates of PJI (odds ratio [OR] 1.34, 95% confidence interval [CI] 1.26-1.43, P < .001). Preoperative UTI within 1 week of THA (OR 1.56, 95% CI 1.44-1.68, P < .001) and between 1-2 weeks prior to THA (OR 1.12, 95% CI 1.02-1.22, P = .022) was associated with significantly higher rates of PJI. UTI diagnosis at any other time interval did not reach statistical significance. Antibiotic prescription was not associated with lower rates of PJI. CONCLUSION: Patients with preoperative UTI within 1 week of TKA or within 2 weeks of THA have an increased risk of postoperative PJI. Antibiotics do not appear to mitigate risk. LEVEL OF EVIDENCE: Level III; Retrospective, database comparison.

Treatment Decision Regret in Patients Who Develop Periprosthetic Joint Infection and Require Two-Stage Revision Surgery.

BACKGROUND: The decision to proceed with total joint arthroplasty (TJA) can be complex and requires an assessment of potential risks of surgery. Patients who experience the potentially devastating complication of periprosthetic joint infection (PJI) may have a poor outcome and wish they had never elected to have surgery. No study has examined decision regret related to the choice to pursue TJA in patients who develop PJI. METHODS: All patients who were treated for PJI with a two-stage revision at a tertiary academic medical center between 2010 and 2020 were surveyed. Ninety-six patients agreed to answer 12 questions concerning their understanding of their preoperative risk of infection and their level of regret with the decision to pursue index TJA. Patient regret was calculated using the Decision Regret Scale. RESULTS: Seventy-two percent of patients reported that their joint replacement and concomitant infection had a severe ongoing impact on their quality of life, although only 28% of respondents regretted their choice to undergo index TJA, and 65% would undergo TJA again. A higher Musculoskeletal Infection Society outcome stage (typically due to failed treatment) and lower understanding of joint infection were associated with a higher level of regret on the Decision Regret Scale (P < .001). CONCLUSION: Self-reported decisional regret was present in only 1 in 4 patients who underwent arthroplasty despite experiencing a devastating complication, and almost two-thirds of patients with PJI reported they would undergo primary TJA again. Patients who were more informed about infection before TJA experienced less regret when they subsequently developed PJI. LEVEL OF EVIDENCE: III.

Increased Morbidity With Diagnosis and Treatment of Pulmonary Embolism After Total Joint Arthroplasty: A Matched Control Analysis of 30,000 Patients.

BACKGROUND: Currently, the risks associated with the diagnosis of pulmonary embolism (PE) and subsequent treatment are not well known. The purpose of our study is to quantify the specific in-hospital complications and resource utilization of patients with PE following total joint arthroplasty when compared to a matched cohort. METHODS: The Nationwide Inpatient Sample database was used to identify patients undergoing primary hip and knee arthroplasty from January 1993 to December 2008. PE was determined using International Classification of Diseases, Ninth Revision, Clinical Modification codes. In-hospital complications, costs, and length of stay for patients with PE were compared to patients without PE, matched on the basis of age, gender, procedure (total hip arthroplasty vs total knee arthroplasty), year of surgery, morbid obesity, and all 28 comorbid-defined elements of the Elixhauser Comorbidity Index. RESULTS: Of 8,634,038 procedures, 30,281 (0.4%) patients had a PE after total joint arthroplasty. In total, 29,917 (98%) were matched one-to-one with patients without PE. Patients with PE had a substantially higher risk of all postoperative in-hospital complications: deep vein thrombosis (odds ratio [OR] 17), peripheral vascular (OR 34), hematoma (OR 3.7), and gastrointestinal bleeding (OR 7.0) (all P < .001). Mortality was significantly higher in patients with PE compared to patients without PE (3.4% vs 0.1%, OR 30), along with total hospital costs, lengths of stay, and rates of discharge to rehabilitation facilities. CONCLUSION: After controlling for comorbidities patients with PE have a significantly higher risk for complications including in-hospital mortality and higher hospital costs when compared to patient without PE.

Trends of Femoral Neck Fracture Treatment Using Total Hip Arthroplasty: Reported From the American Joint Replacement Registry.

INTRODUCTION: Total hip arthroplasty (THA) rather than hemiarthroplasty for displaced femoral neck fracture (FNF) is often chosen for younger patients who are more active and/or have underlying hip osteoarthritis. However, instability remains the primary concern of doing THA. Dual mobility (DM) has been shown to decrease this risk through a larger effective head size and greater head-to-neck ratio compared with conventional THA. The purpose of this study was to identify femoral head size and DM usage patterns for the treatment of FNF with THA in the United States using the American Joint Replacement Registry. METHODS: A retrospective cohort study was conducted, including all primary THAs done for FNF from 2012 to 2019. THA and FNF were defined using Current Procedural Terminology or International Classification of Diseases-9 or -10 diagnosis and procedure codes. Analysis was based on patient demographics, femoral head size, and DM usage. Descriptive statistics were used using a Pearson chi-square test. All analyses were conducted using SAS version 9.4, and statistical significance was set at P < 0.05. RESULTS: There were 18,752 THAs done by 3,242 surgeons at 789 institutions during the 8-year study period. The overall population was 66% female, and the mean age was 72.3 ± 11.8 years. The most commonly used femoral head size was 36 mm (48.5%) followed by 32 mm (24.5%), ≤28 mm (10.7%), DM (10.8%), and ≥40 mm (5.7%). A trend was observed toward decreased use of ≤28, 32, and ≥40-mm heads starting in 2016 across the years and increased use of 36-mm heads (P < 0.0001). A significant increase was observed in the usage of DM over time from 6.4% in 2012 to 16.2% in 2019 (P < 0.0001). DISCUSSION: Most of the femoral heads used were ≥36 mm, and the use of DM increased during the study period. Additional analysis is warranted to understand how these trends will affect overall outcomes and postoperative dislocation rates.

Patient Perspectives on the Cancellation of Elective Primary Hip and Knee Arthroplasty During the COVID-19 Pandemic.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic resulted in the unprecedented widespread cancellation of scheduled elective primary total joint arthroplasty (TJA) in the United States. The impact of postponing scheduled total hip arthroplasty and total knee arthroplasty procedures on patients has not been well studied and may have physical, emotional, and financial consequences. METHODS: All patients whose elective primary TJA procedures at a tertiary academic medical center were postponed because of COVID-19 were surveyed. Seventy-four patients agreed to answer 13 questions concerning the physical, mental, and financial impact of surgery cancellation. Statistical analysis, including Pearson correlation coefficients, cross-tabulation analysis, and chi squares, was performed. RESULTS: 13.5% of patients strongly disagreed with the use of "elective" to describe their cancelled TJA surgery and 25.7% of patients reported substantial physical and/or mental deterioration due to postponement. Younger individuals experienced greater change in their symptoms (P = 0.034), anxiety about their pain (P = 0.010), and frustration/anger (P = 0.043). Poor quality of life, mood, and lower HOOS/KOOS Jr interval scores were correlated with greater financial strain, disagreement with the postponement, and disagreement with the use of "elective" to describe surgery. Disagreement with the use of "elective" to describe surgery was associated with greater financial strain (P = 0.013) and disagreement with the decision to postpone surgery (P = 0.008). In addition, greater financial strain was associated with disagreement with postponement (P = 0.014). CONCLUSION: The cancellation of elective TJA during the COVID-19 pandemic had a variety of consequences for patients. One in four patients reported experiencing substantial physical and/or emotional deterioration. Associations of poor quality of life and mood with greater financial strain and disagreement with the term "elective" were seen. These results help quantify the deleterious effects of cancelling elective surgery and identify at-risk patients should another postponement of surgery occur. LEVEL OF EVIDENCE: Level II-Prospective cohort study.

Krüppel-like factor 5 regulates wound repair and the innate immune response in human airway epithelial cells.

A complex network of transcription factors regulates genes involved in establishing and maintaining key biological properties of the human airway epithelium. However, detailed knowledge of the contributing factors is incomplete. Here we characterize the role of Krüppel-like factor 5 (KLF5), in controlling essential pathways of epithelial cell identity and function in the human lung. RNA-seq following siRNA-mediated depletion of KLF5 in the Calu-3 lung epithelial cell line identified significant enrichment of genes encoding chemokines and cytokines involved in the proinflammatory response and also components of the junctional complexes mediating cell adhesion. To determine direct gene targets of KLF5, we defined the cistrome of KLF5 using ChIP-seq in both Calu-3 and 16HBE14o- lung epithelial cell lines. Occupancy site concordance analysis revealed that KLF5 colocalized with the active histone modification H3K27ac and also with binding sites for the transcription factor CCAAT enhancer-binding protein beta (C/EBPß). Depletion of KLF5 increased both the expression and secretion of cytokines including IL-1ß, a response that was enhanced following exposure to Pseudomonas aeruginosa lipopolysaccharide. Calu-3 cells exhibited faster rates of repair after KLF5 depletion compared with negative controls in wound scratch assays. Similarly, CRISPR-mediated KLF5-null 16HBE14o- cells also showed enhanced wound closure. These data reveal a pivotal role for KLF5 in coordinating epithelial functions relevant to human lung disease.

The Impact of Mental Illness on Postoperative Adverse Outcomes After Outpatient Joint Surgery.

BACKGROUND: The effect of pre-existing mental illness on outpatient surgical outcomes is not well characterized. The objective of this study was to evaluate the association between pre-existing mental illness diagnosis and postoperative complications after outpatient total knee (TKA) and total hip arthroplasty (THA) and 2) compare with inpatient total joint arthroplasty (TJA). METHODS: The Mariner Claims Database was used to capture patients undergoing outpatient TJA from 2010 to 2017. Patients were grouped into three categories: those with an existing history of anxiety and/or depression, those with severe mental illness, and those without history of mental illness. Additional subgroup analysis compared those with severe mental illness undergoing outpatient vs inpatient TJA. Outcomes were analyzed using multivariable logistic regression (P < .05). RESULTS: Patients undergoing outpatient TJA with prior history of anxiety and/or depression or severe mental illness had an increased risk of emergency department (ED) visits (TKA, P < .001; THA, P = .014) within 90 days compared with those without history of mental illness. Severe mental illness was also associated with increased risk of medical complications at 90 days (TKA, P < .001; THA, P = .006). When compared with those undergoing inpatient surgery, patients undergoing outpatient TKA with severe mental illness were at increased risk of periprosthetic infection (P = .005) and ED visit (P = .003) within 90 days of surgery. CONCLUSION: Anxiety/depression and severe mental illness are associated with higher rates of ED visits after outpatient TJA. Patients with severe mental illness also experienced more adverse events, whereas those with anxiety and/or depression had similar rates compared with control. A higher rate of adverse outcomes was seen after TKA in patients with severe mental illness when surgery was performed in the outpatient setting vs those that had surgery as an inpatient. LEVEL OF EVIDENCE: III.

Reimbursements for Revision Total Hip Arthroplasty Have Increased for Hospitals but Not for Surgeons.

BACKGROUND: With increases in total hip arthroplasty procedures the need for revision total hip arthroplasty (rTHA) has increased as well. This study aims to analyze the trends in hospital charges and payments relative to corresponding surgeon charges and payments in a Medicare population for rTHA for aseptic revisions, stage 1 and stage 2 revisions. METHODS: The 5% Medicare sample database was used to capture hospital and surgeon charges and payments related to 4449 patients undergoing aseptic revision, 517 for stage 1 revision, and 300 for stage 2 revision in between the years 2004 and 2014. Two values were calculated: (1) the ratio of hospital to surgeon charges (CM) and (2) the ratio of hospital to surgeon payments (PM). Year-to-year variation and trends in patient demographics, Charlson Comorbidity Index (CCI), length of stay (LOS), CM, and PM were evaluated. RESULTS: The mean CCI for aseptic revisions and stage 1 revisions did not significantly change (P < .088 and P < .063). The CCI slightly increased for stage 2 revisions (P < .04). The mean LOS decreased significantly over time in all 3 procedure types. The CM increased by 39% (P < .02) in aseptic revisions, 109% in stage 1 revisions (P < .001) but did not significantly change in stage 2 revisions (P < .877). PM for aseptic revisions increased around 103% (P < .001), 107% for stage 1 revisions (P < .001), and 9.7% for stage 2 revisions (P < .176). CONCLUSION: Hospital charges and payments relative to surgeon charges and payments have increased substantially for THA aseptic revisions, stage 1 revisions, and stage 2 revisions despite stable patient complexity and decreasing LOS.

Prior Nonarthroplasty Surgery Increases Risk of Complication in Primary Total Knee Arthroplasty.

BACKGROUND: Prior ipsilateral knee surgery may increase the risk for complications after total knee arthroplasty (TKA). It remains unclear if the extent of previous surgery affects those risks disparately. The purpose of this study is to evaluate prior nonarthroplasty bony procedure (BP) and soft tissue only procedure (STP) as a potential risk factor for complications after TKA and determine the association with charges or reimbursement of the primary TKA. METHODS: Patients who underwent primary TKA with previous knee surgery were identified using a national Medicare database and matched 1:5 to controls without prior knee surgery. Rates of postoperative medical and surgical complications were calculated in addition to hospital-associated charges and reimbursements. Logistic regression analysis was used to control for confounding factors. RESULTS: Patients who underwent BP (n = 835) had increased risk of readmission (58.6% vs 45.3%, odds ratio (OR) 1.72, 95% confidence interval (CI) 1.59-1.85, P < .001) and emergency room visits (14.5% vs 10.4%, OR 1.44, 95% CI 1.29-1.61, P = .001). Patients who underwent STP (n = 6766) had increased risk of readmission (58.1% vs 45.2%, OR 1.69, 95% CI 1.64-1.73, P < .001), emergency room visits (12.6% vs 0.7%, OR 1.33, 1.28-1.39, P < .001), revision (1.8% vs 1.4%, OR 1.33, 95% CI 1.21-1.47, P = .006), cerebrovascular accident (2.3% vs 1.7%, OR 1.33, 95% CI 1.22-1.46, P = .002), and venous thromboembolism (3.8% vs 3.2%, OR 1.21, 95% CI 1.13-1.29, P = .009). Prior surgery was associated with increased charges and reimbursements. CONCLUSION: Prior ipsilateral knee surgery is associated with significantly increased risks of postoperative complications after primary TKA. Interestingly, previous STP but not BP increased the risk of short-term revision and venous thromboembolism.