Discriminative Ability of Elixhauser's Comorbidity Measure is Superior to Other Comorbidity Scores for Inpatient Adverse Outcomes After Total Hip Arthroplasty

Risk Stratification in Orthopaedic Surgery: An Important Adjustment for Value-Based Health Care and Quality Measurement

➢ Risk stratification in orthopaedic surgery is complex and depends on the outcome of interest and multiple interdependent factors. Effective risk stratification has uses for limiting and predicting adverse events in patients undergoing discretionary surgery, avoiding the penalization of surgeons for operating on candidates whose health is situated in more difficult circumstances, and ensuring that inordinate attention is not placed on discrete musculoskeletal pathophysiology when there are other pressing health priorities.➢ For individual patient decision-making, no comprehensive risk-stratification tool currently exists, in part due to the heterogeneity of orthopaedic procedures performed and the diverse patient population treated. The Elixhauser Comorbidity Measure and the Risk Stratification Index 3.0 appear to be most promising.➢ At a population level, risk stratification may be useful in alternative payment models to ensure that hospitals that treat a disproportionate number of high-risk patients are not penalized and that cherry-picking (preferentially selecting only healthier patients with a lower risk of complications) does not occur. Any attempt to risk-stratify may have unintended consequences.➢ Orthopaedic surgeons must be aware of the tools available, their strengths, and their limitations in order to be included in decision-making as payment models and public health policies are implemented.

A Higher Area Deprivation Index Is Associated With Increased Medical Complications and Emergency Department Utilizations After Total Hip Arthroplasty

BACKGROUND

The Area Deprivation Index (ADI) is a weighted index comprised of 17 census-based markers of material deprivation and poverty. The purpose of this study was to determine whether patients undergoing total hip arthroplasty (THA) in areas of high ADI (greater disadvantage) were associated with differences in 90 days: 1) medical complications; 2) emergency department (ED) utilizations; and 3) readmissions.

METHODS

A nationwide database was queried for primary THA patients from 2010 to 2020. The ADI is reported on a scale of 0 to 100, with higher numbers indicating greater disadvantage. Patients undergoing primary THA in regions associated with high ADI (90%+) were compared to those of lower ADI (0 to 89%). A total of 138,670 patients were evenly matched between the two cohorts following 1:1 propensity score matching by age, sex, and Elixhauser Comorbidity Index. Primary endpoints were 90-day medical complications, ED utilizations, and readmissions. Multivariable logistic regression models calculated the odds ratios (ORs) and 95% confidence intervals (CIs). P values less than 0.01 were statistically significant.

RESULTS

Patients undergoing THA from high ADI had significantly higher rates and odds of developing any medical complications (13.0 versus 11.9%; OR: 1.09, P < 0.0001), including acute kidney injuries (1.8 versus 1.5%; OR: 1.20, P < 0.0001), myocardial infarctions (0.35 versus 0.24%; OR: 1.45, P = 0.0003), and surgical site infections (0.94 versus 0.76%; OR: 1.23, P = 0.0004). High-ADI patients had significantly higher rates and odds of ED visits within 90 days (3.94 versus 3.67%; OR: 1.08, P = 0.008). There was no significant difference in readmissions (5.44 versus 5.69%; OR: 0.95, P = 0.034).

CONCLUSIONS

Socioeconomically disadvantaged patients have increased odds of 90-days medical complications and ED utilizations, despite comparable 90-day readmission rates. Measures of neighborhood disadvantage may be valuable metrics to inform health care policy and improve postdischarge care.

Impact of Hospital Case Volume on the Complication Rate in Hip Arthroplasty: An Analysis of Nationwide AOK Data

Aufgrund des demografischen Wandels und damit verbundener erwarteter Steigerungen der Fallzahlen von primärer Hüftendoprothetik und Revisionseingriffen ist es wichtig, Faktoren zu identifizieren, die Komplikationen und Revisionen reduzieren können. Ein solcher Faktor ist die Fallzahl eines Krankenhauses. Studien haben gezeigt, dass Krankenhäuser mit höheren Fallzahlen niedrigere Morbiditäts- und Komplikationsraten aufweisen. Die meisten Studien basieren dabei auf Registerdaten, die oft unvollständig sind und keine patientenspezifischen Faktoren beinhalten.In dieser Studie wurden bundesweite pseudonymisierte stationäre Abrechnungsdaten und Versichertenstammdaten der Allgemeinen Ortskrankenkassen (AOK) im Zeitraum von 2017 bis 2019 bei Patienten mit primärer Hüftendoprothese analysiert. Zur Analyse des Einflusses der Fallzahl auf das Outcome wurden 5 Fallzahlkategorien gebildet (I: 1-49, II: 50-99, III: 100-199, IV: 200-399, V: ≥ 400 Operationen pro Jahr). Als Endpunkte wurden 90-Tage-Sterblichkeit, 1-Jahres-Revisionsoperationen, chirurgische Komplikationen (90 Tage bzw. 365 Tage), periprothetische Femurfrakturen (90 Tage) und schwere Allgemeinkomplikationen im Krankenhausaufenthalt betrachtet. Der Einfluss der Fallzahl auf das Outcome wurde mittels multipler logistischer Regression unter Berücksichtigung patientenspezifischer Faktoren bestimmt.Die Analyse von 137494 Fällen aus 993 Kliniken zeigt einen statistisch signifikanten Zusammenhang zwischen der Fallzahlgruppe und der Häufigkeit von Revisionsoperationen, chirurgischen Komplikationen, periprothetischen Femurfrakturen und allgemeinen Komplikationen. Bei Kliniken mit einer Fallzahl von weniger als 50 pro Jahr zeigte sich eine Risikoerhöhung um 65%-88% für diese Endpunkte gegenüber der fallzahlstärksten Gruppe. Für den Endpunkt Sterblichkeit ergibt eine dichotome Betrachtung der Fallkategorien ebenfalls einen signifikanten Einfluss der Fallzahlen.Die Studie zeigt, dass, auch unter Berücksichtigung patientenspezifischer Faktoren, höhere Fallzahlen bei primärer Hüftendoprothetik in Krankenhäusern mit niedrigeren Komplikationsraten verbunden sind. Diese Erkenntnisse unterstreichen die Bedeutung der Fallzahl als Faktor zur Verbesserung der Versorgungsqualität in der Hüftendoprothetik.

Comparing general and regional anesthesia in patients undergoing primary total hip arthroplasty: analysis of national health insurance data in Korea

Objectives

To compare the effects of general and regional anesthesia on clinical outcomes following primary total hip arthroplasty (THA).

Methods

This retrospective study using data from the Korean National Health Insurance Research Database included 1,522 patients who underwent THA under general anesthesia (n = 640) or regional anesthesia (n = 882) between 2002 and 2015. We compared the mortality and complication rates within 30 days after surgery.

Results

Prosthesis failure (1.56% vs. 0.45%, p = 0.025), admission to the intensive care unit (9.53 vs. 5.44%, p = 0.0023), and total cost (₩7,332,515 vs. ₩6,833,295, p < 0.0001) were higher in the general anesthesia group than in the regional anesthesia group. No significant differences were observed in mortality (0.94% vs. 0.57%, p = 0.54), transfusion rate (81.1% vs. 80.9%, p = 0.94), length of hospital stay (45 vs. 45 days, p = 0.23), or other complications between the groups. Similar results were observed in propensity-score matched analysis (n = 640 patients per group).

Conclusion

Our study showed that both anesthesia types resulted in comparable mortality and complication rates in patients who underwent THA, but the costs differed.

Clinical frailty scale predicts outcomes following total joint arthroplasty

BACKGROUND

As the population ages, the number of total joint arthroplasty (TJA) performed is rising, making early identification of patients at risk for adverse events essential to improving care and reducing healthcare costs. The aim of this study was to evaluate the association between Clinical Frailty Scale (CFS) and postoperative outcomes in elective total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

We conducted a retrospective study of prospectively collected data regarding 328 TKAs and 294 THAs at a single institution from February 2019 to February 2020. Patient demographic data were harvested, and the preoperative CFS scores were calculated for all patients and analyzed to identify their associations with the length of stay (LOS), the need for admission to an inpatient rehabilitation unit (IPRU), postoperative complications and patient-reported outcome measures (PROMs).

RESULTS

Robust patients (CFS < 3) had a significantly shorter LOS than their non-robust (CFS > 3) counterparts in both the TKA and THA groups (3.7 vs. 5.2 days, P < 0.001, and 3.8 vs. 5.8 days, P < 0.001, respectively). IPRU admission rates were significantly higher in non-robust than in robust patients. Specifically, none of the robust TKA patients required IPRU admission, whereas up to 39 non-robust patients (11.9%) did (P < 0.001). Similarly, for THA, 9 robust (5.7%) and 30 non-robust (21.9%) patients were admitted to an IPRU (P < 0.001). Non-robust patients had a significantly higher complication rate for both THA (11.0% vs. 6.4%, P = 0.03) and TKA (8.7% vs. 2.6%, P = 0.11). Both cohorts showed significant improvements in PROMs post-surgery, with non-robust patients experiencing greater relative gains than robust patients.

CONCLUSIONS

CFS is a strong predictor of the hospital length of stay, IPRU admission, and complication rates following TJA. This study also highlighted the link between frailty and PROMs in joint replacement patients. The CFS may be a valuable tool in the preoperative assessment of elective THA and TKA.

What Factors Influence In-Hospital Mortality Following Aseptic Revision Total Hip Arthroplasty? A Single-Center Analysis of 13,203 Patients

BACKGROUND

Revision total hip arthroplasty (rTHA) is associated with an extended surgical period, an increased hospitalization period, expanded blood loss, and high mortality rates. The purpose of the present study was to assess the risk factors that contribute to in-hospital mortality following aseptic rTHA.

METHODS

We performed a retrospective examination of the medical records of all patients who underwent elective rTHA surgery at our tertiary referral arthroplasty center between March 1996 and March 2019. The study involved a group of 13,203 patients, including 70 who expired during hospitalization and 13,133 in the control group. Baseline characteristics, medical history, comorbidities, and surgery-related parameters of the patients were recorded. Logistic regression analyses were performed to examine the association between independent variables and in-hospital mortalities, which were presented as odds ratios (ORs) and confidence intervals (CIs).

RESULTS

Patient factors associated with in-hospital mortality included hepatitis C (OR 75.5, 95% CI 3.5 to 1,625.2), chronic obstructive pulmonary disease (OR 30.7, 95% CI 6.5 to 145.7), rheumatoid arthritis (OR 28.9, 95% CI 3.8 to 218.5), history of myocardial infarction (OR 24.9, 95% CI 4.4 to 140.8), history of cerebrovascular disease (OR 23.1, 95% CI 3.8 to 142), congestive heart failure (OR 18.9, 95% CI 3.8 to 94.2), and diabetes mellitus (OR 10.2, 95% CI 2.4 to 42.6). Surgical factors included the history of multiple prior revisions (OR 1.75, 95% CI 1.1 to 2.7), postoperative blood transfusion (OR 2.8, 95% CI 1.1 to 7.3), and decreased preoperative hemoglobin (OR 2.3, 95% CI 1.7 to 3.1).

CONCLUSIONS

Several patient-related and intraoperative factors significantly increased the risk of in-hospital mortality following aseptic rTHA. Vigilance and close perioperative monitoring are essential for patients undergoing this complex surgery.

LEVEL OF EVIDENCE

III.

Anterior Cervical Discectomy and Fusion Associated with Increased Home Discharge Rates in Geriatric Patients with Cervical Disc Herniation Compared to Posterior Cervical Decompression and Fusion: A Propensity-Matched Analysis

INTRODUCTION

Cervical disc herniation often necessitates surgery in elderly patients when nonoperative treatments fail. This study compares discharge outcomes of anterior cervical discectomy and fusion (ACDF) vs. posterior cervical decompression and fusion (PCDF) in geriatric patients.

METHODS

A retrospective analysis of 8622 spine surgery patients (January 2008-December 2020) was performed. Geriatric patients (age ≥65) undergoing primary 2-4 level ACDF or PCDF were included. Propensity score matching (1:1) based on age, sex, ethnicity, body mass index, insurance, American Society of Anesthesiologists classification, Elixhauser comorbidity index, preoperative diagnosis, fusion levels, estimated blood loss, intraoperative transfusion, and procedure length was used. Discharge outcomes were dichotomized to home or nonhome.

RESULTS

After matching, 122 patients (ACDF = 61, PCDF = 61) were analyzed. A larger proportion of ACDF patients were discharged home compared to PCDF (84% vs. 64%, P = 0.02). On binary logistic regression, younger age (OR = 0.88 [0.79, 0.98], P = 0.02), male sex (OR = 2.04 [1.79, 3.28], P = 0.001), lower estimated blood loss (OR = 0.99 [0.99, 0.99], P = 0.001), intraoperative transfusion (OR = 0.43 [0.22, 0.92], P = 0.03), and ACDF approach (OR = 4.34 [1.91, 6.77], P = 0.01) were significant predictors of home discharge.

CONCLUSIONS

ACDF in geriatric patients with cervical disc herniation was associated with higher rates of home discharge compared to PCDF. Tailored surgical approaches based on patient demographics may improve recovery outcomes.

A high hospital frailty risk score indicates an increased risk for complications following surgical treatment of proximal humerus fractures

BACKGROUND

Approximately 70 % of proximal humerus fractures (PHF) occur after the age of 60. High complication rates have been described in correlation with the treatment of PHF. Major risk factors for the outcome might be frailty, mobility and comorbidities of patients at the time of hospital admission. The aim of this study was to create risk adjusted quality indicators for surgical treatment of proximal humerus fractures based on German claims data and to evaluate the impact of the Hospital Frailty Risk Score (HFRS) on risk adjustment.

METHODS

Retrospective claims data (2015-2021) were used to create risk adjusted quality indicators for eight outcomes by clustered multivariable logistic regression. The comparison of different risk adjustment model performances was done by ROC-AUC and Standardized Mortality/Morbidity Ratios.

RESULTS

In total, N = 34,912 patients (median age 75 years, 80.3 % female) were included. The most common surgical procedure was open reduction and internal fixation with plate osteosynthesis with 39.7 %, followed by reverse shoulder arthroplasty with 25.3 %. The most influential risk factor for all outcomes was a high HFRS with an Odds Ratio of 2.0 (95 %-Confidence Interval 1.8-2.3) for any secondary surgery (365 days) up to an Odds Ratio of 17.6 (95 %-Confidence Interval 14.9-20.8) for general complications during the index stay.

CONCLUSION

Comparative quality reporting for the surgical treatment of PHF appears feasible with the developed models for risk adjustment using claims data. Preoperative evaluation of HFRS in PHF can contribute to risk assessment, and individual patient management. It therefore enables personalized treatment decisions.

Common comorbidity indices fail to predict short-term postoperative outcomes following male urethroplasty

PURPOSE

To evaluate whether commonly used comorbidity indices [Charlson Comorbidity Index (CCI), Van Walraven Index (VWI), and modified frailty index (mFI)] predict postoperative readmissions and complications after urethroplasty.

METHODS

Patients undergoing urethroplasty for urethral stricture from the State Inpatient Database and State Ambulatory Surgery and Services Database for Florida (2010-2015) and California (2010-2011) were identified. We calculated CCI, VWI, and mFI scores for each patient. We extracted the following adverse outcomes: 30 day ER services, 30 day inpatient readmissions, and 90 day Clavien-Dindo III-V complications. We constructed receiver operating characteristic (ROC) curves and compared area under the curve (AUC), using the VWI as the reference index.

RESULTS

We identified 908 urethroplasty patients. Among these patients, 11.5% (n = 104) of patients had a complication, with 4.8% (n = 44) specifically having 30-day ER services, 6.2% (n = 56) having 30 day readmissions, and 9.0% (n = 82) having 90-day Clavien-Dindo III-V complications. ROC curves demonstrated poor predictive performances for all four indices as no index achieved an AUC > 0.70. The indices performed similarly poorly but the mFI-DX was particularly poor at predicting 90 day Clavien-Dindo III-V complications (AUC = 0.49; 95% CI 0.43-0.55; p < 0.01).

CONCLUSIONS

The CCI, VWI, and mFI have poor ability to identify patients who had an adverse event after urethroplasty. Our results support the need for a urology-specific comorbidity index to better identify at-risk patients undergoing urethroplasty.

Neighborhood Deprivation and Association With Medical Complications, Emergency Department Use, and Readmissions in Shoulder Arthroplasty Patients

Background

Social determinants of health are prognostic indicators for patients undergoing orthopedic procedures.

Purpose

Using the area deprivation index (ADI), a validated, weighted index of material deprivation and poverty (a 0%-to-100% scale, with higher percentages indicating greater disadvantage), we sought to evaluate whether there are associations in shoulder arthroplasty patients between higher ADI and rates of (1) medical complications, (2) emergency department (ED) utilizations, (3) readmissions, and (4) costs.

Methods

We queried the PearlDiver nationwide database for patients who had undergone primary shoulder arthroplasty from 2010 to 2020. Patients from regions associated with high ADI (95%+) were 1:1 propensity matched to a comparison group by age, sex, and Elixhauser Comorbidity Index. This yielded 49,440 patients in total. Outcomes included 90-day complications, ED utilizations, readmissions, and costs. Logistic regression models computed odds ratios (ORs) of ADI on the dependent variables. P values of < .05 were significant.

Results

Patients from high ADI regions showed higher rates and odds of complications than those in the comparison group (10.84% vs 9.45%; OR: 1.10), including acute kidney injuries (1.73% vs 1.38%; OR: 1.23), urinary tract infections (3.19% vs 2.80%; OR: 1.13), and respiratory failures (0.49% vs 0.33%; OR: 1.44), but not increased ED visits (2.66% vs 2.71%; OR: 0.99) or readmissions (3.07% vs 2.96%; OR: 1.03). Patients from high ADI regions incurred higher costs on day of surgery ($8251 vs $7337) and at 90 days ($10,999 vs $9752).

Conclusions

This 10-year retrospective database study found that patients from high ADI regions undergoing primary shoulder arthroplasty had increased rates of all 90-day medical complications, suggesting that measures of social determinants of health could inform health care policy and improve post-discharge care in these patients.

Robotic-Assisted Versus Navigation-Assisted Posterior Lumbar Fusion : A National Database Study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to compare perioperative adverse events and reoperations between navigation-assisted and robotic-assisted posterior lumbar fusion.

SUMMARY OF BACKGROUND DATA

Navigation has become increasingly utilized for posterior lumbar fusion (PLF). More recently, robotic-assisted systems have been gaining traction. However, the incremental advantage of these systems has been unclear in the literature.

METHODS

Patients undergoing one-level to three-level PLF (with or without anterior or posterior interbody fusion) were identified from the 2015 to 2022 M161Ortho PearlDiver Database using CPT codes. Navigation assistance was identified based on CPT coding and robotic assistance was based on ICD-10 procedural coding. Navigation-assisted cases were matched 4:1 to robotic-assisted patients based on age, sex, Elixhauser Comorbidity Index, number of levels fuse, and concomitant anterior fusion. Incidence of 90-day adverse outcomes were assessed and compared with multivariable logistical regression. Bonferroni correction was applied for multiple testing. Rate of reoperation was assessed using the Kaplan-Meier survival analysis.

RESULTS

From 2015 to 2022, there has been a significant increase in both navigation-assisted and robotic-assisted lumbar fusions, with navigation-assisted surgery being significantly more common. After matching, there were 2401 navigation-assisted cases and 651 robotic-assisted cases. On multivariate analysis, there were no significant differences in 90-day any, severe, or minor adverse events. There was a significant increase odd of readmissions in the robotic cohort (OR: 1.77, P <0.001). There were no differences in 3-year reoperation rates between the navigation-assisted and robotic-assisted cohorts (95.8% vs. 94.0%, P =0.30).

CONCLUSIONS

As spinal navigation has been gaining popularity and robotic assistance is starting to be further utilized, the incremental advantage of different techniques may be questioned. While further study and technique evolution are ongoing, the current study was not able to demonstrate 90-day or 3-year incremental advantages for robotics relative to navigation based on the metrics evaluated.

LEVEL OF EVIDENCE

Level III.

Metabolic syndrome in the setting of obesity: impact on in-hospital complications and outcomes after total knee and hip arthroplasty

Aims

This study aims to evaluate the impact of metabolic syndrome in the setting of obesity on in-hospital outcomes and resource use after total joint replacement (TJR).

Methods

A retrospective analysis was conducted using the National Inpatient Sample from 2006 to the third quarter of 2015. Discharges representing patients aged 40 years and older with obesity (BMI > 30 kg/m2) who underwent primary TJR were included. Patients were stratified into two groups with and without metabolic syndrome. The inverse probability of treatment weighting (IPTW) method was used to balance covariates.

Results

The obese cohort with metabolic syndrome was significantly older, more likely to be female, had higher rates of Medicare insurance, and more likely to be non-Hispanic Black than the obese cohort without metabolic syndrome. In the unweighted analysis, patients with obesity and metabolic syndrome were more likely to experience cardiac, gastrointestinal, genitourinary, and postoperative anemia complications, had a longer length of stay, and were less likely to be discharged home compared to obese patients without metabolic syndrome. After adjusting for covariates using IPTW, patients with obesity and metabolic syndrome were more likely to experience postoperative anemia complications only and had lower rates of home discharge, but there were no significant differences in any other complication variables or length of stay.

Conclusion

Given the variability of metabolic health in obesity, the development of tailored perioperative protocols and recommendations acknowledging this variability in metabolic health in obese patients would ultimately potentially benefit patients and improve outcomes of TJR.

Clostridium difficile Infection Prior to Total Hip Arthroplasty Independently Increases the Risk of Periprosthetic Joint Infection

BACKGROUND

Periprosthetic joint infection (PJI) following total hip arthroplasty (THA) is associated with major morbidity. There may be a link between the gut microbiome and an individual's overall immune system. A Clostridium difficile (C. difficile) infection portends poor gut microbiome health and has been previously associated with increased 90-day complication rates in total joint arthroplasty (TJA). The purpose of this study was to determine the effect of a previous history of C. difficile infection within 2 years of undergoing THA on PJI within 2 years postoperatively.

METHODS

Patients undergoing THA from 2010 to 2021 were identified in a patient claims database (n = 770,075). Patients who had active records 2 years before and after THA as well as a history of C. difficile infection within 2 years prior to THA (n = 1,836) were included and propensity matched to a control group using age, sex, and Elixhauser comorbidity index. The primary outcome was the 2-year incidence of postoperative PJI. The exposed C. difficile infection cohort was stratified into 4 groups based on the time proximity of the C. difficile infection. Chi-square tests and logistic regressions were used to compare the groups.

RESULTS

A C. difficile infection anytime within 2 years prior to total hip arthroplasty was independently associated with higher odds of PJI (OR [odds ratio]: 1.49 [95% CI (confidence interval) 1.09 to 2.02, P = .014]). Proximity of C. difficile infection to arthroplasty was associated with increased risk of PJI (infection 0 to 3 months before THA: OR 2.01 [95% CI 1.23 to 3.20], infection 3 to 6 months before THA: OR 1.84 [95% CI 1.06 to 3.04], infection 6 to 12 months before THA: OR 1.10 [95% CI 0.65 to 1.77], infection 1 to 2 years before THA: OR 1.40 [95% CI 0.94 to 2.06]).

CONCLUSIONS

A C. difficile infection prior to THA is an independent risk factor for PJI. Proximity of C. difficile infection is associated with increased risk of PJI. Future investigations should evaluate how to adequately optimize patients prior to THA and pursue strategies to determine appropriate timing for proceeding with THA.

A Nationwide Analysis of the Impact of Socioeconomic Status on Complications and Health Care Utilizations After Total Knee Arthroplasty Using the Area Deprivation Index: Consideration of the Disadvantaged Patient

BACKGROUND

Socioeconomic status has been demonstrated to be an important prognostic risk factor among patients undergoing total joint arthroplasty. We evaluated patients living near neighborhoods with higher socioeconomic risk undergoing total knee arthroplasty (TKA) and if they were associated with differences in the following: (1) medical complications; (2) emergency department (ED) utilizations; (3) readmissions; and (4) costs of care.

METHODS

A query of a national database from 2010 to 2020 was performed for primary TKAs. The Area Deprivation Index (ADI) is a weighted index comprised of 17 census-based markers of material deprivation and poverty. Higher numbers indicate a greater disadvantage. Patients undergoing TKA in zip codes associated with high ADI (90%+) were 1:1 propensity-matched to a comparison group by age, sex, and Elixhauser Comorbidity Index. This yielded 225,038 total patients, evenly matched between cohorts. Outcomes studied included complications, ED utilizations, readmission rates, and 90-day costs. Logistic regression models computed the odds ratios (OR) of ADI on the dependent variables. P values less than .003 were significant.

RESULTS

High ADI led to higher rates and odds of any medical complications (11.7 versus 11.0%; OR: 1.05, P = .0006), respiratory failures (0.4 versus 0.3%; OR: 1.28, P = .001), and acute kidney injuries (1.7 versus 1.5%; OR: 1.15, P < .0001). Despite lower readmission rates (2.9 versus 3.5%), high ADI patients had greater 90-day ED visits (4.2 versus 4.0%; OR: 1.07, P = .0008). The 90-day expenditures ($15,066 versus $12,459; P < .0001) were higher in patients who have a high ADI.

CONCLUSIONS

Socioeconomically disadvantaged patients have increased complications and ED utilizations. Neighborhood disadvantage may inform health care policy and improve postdischarge care. The socioeconomic status metrics, including ADI (which captures community effects), should be used to adequately risk-adjust or risk-stratify patients so that access to care for deprived regions and patients is not lost.

LEVEL OF EVIDENCE

III.

Comparing Common Risk Assessment Tools to Predict Outcomes in Total Knee Arthroplasty

BACKGROUND

A number of tools exist to aid surgeons in risk assessment, including the Charlson Comorbidity Index (CCI), the Elixhauser Comorbidity Index (ECI), and various measures of frailty, such as the Hospital Frailty Risk Score (HFR). While all of these tools have been validated for general use, the best risk assessment tool is still debated. Risk assessment is particularly important in elective surgery, such as total joint arthroplasty. The aim of this study is to compare the predictive power of the CCI, ECI, and HFR in the setting of total knee arthroplasty (TKA).

METHODS

All patients who underwent TKA were identified via International Statistical Classification of Diseases and Related Health Problems, Tenth Revision code from the National Readmissions Database, years 2016 to 2019. Patient demographics, perioperative complications, and hospital-associated outcomes were recorded. Receiver operating characteristic (ROC) curves were created and area under the curves (AUCs) evaluated to gauge the predictive capabilities of each risk assessment tool (CCI, ECI, and HFR) across a range of outcomes.

RESULTS

A total of 1,930,803 patients undergoing TKA were included in our analysis. For mortality, ECI was most predictive (0.95 AUC), while HFR and CCI were 0.75 and 0.74 AUC, respectively. For periprosthetic fractures, ECI was 0.78 AUC, HFR was 0.68 AUC, and CCI was 0.66 AUC. For joint infections, the ECI was 0.78 AUC, the HFR was 0.63 AUC, and the CCI was 0.62 AUC. For 30-day readmission, ECI was 0.79 AUC, while HFR and CCI were 0.6 AUC. For 30-day reoperation, ECI was 0.69 AUC, while HFR was 0.58 AUC and CCI was 0.56 AUC.

CONCLUSIONS

Our analysis shows that ECI is superior to CCI and HFR for predicting 30-day postoperative outcomes following TKA. Surgeons should consider assessing patients using ECI prior to TKA.

Risk Factors for Perioperative Nerve Injury Related to Total Hip Arthroplasty

Background

Nerve injury following total hip arthroplasty (THA) is a rare but serious adverse event. While prior studies have reported risk factors for nerve injury related to THA, they are limited to institutional data or small sample sizes. The current study aimed to leverage a large, national database to assess independent risk factors for sustaining nerve injury with THA.

Methods

The 2010-2021 PearlDiver M157 database was queried for adult THA cases. Those with nerve injury within 90 days of THA were identified. Patient age, sex, body mass index (BMI), Elixhauser comorbidity index (ECI), fracture indication, and surgery type (index vs revision) were assessed for correlation with nerve injury by multivariate analyses.

Results

Out of 750,695 THAs, 2659 (0.35%) had nerve injuries. Multivariate analysis revealed independent predictors of nerve injury in decreasing odds ratio (OR) order to include: revision procedure (OR: 2.13), female sex (OR 1.35), ECI (ECI 1-2 [OR 1.27], ECI 3-4 [OR 1.43], and ECI ≥5 [OR 1.59]) and age (OR 1.02 per decade decrease) (P < .05 for each). Pertinent negatives by multivariate analysis included underweight BMI (<20), and fracture indication. Individuals with morbidly obese BMI status (≥35) had a decreased risk of nerve injury (OR 0.84, P = .019).

Conclusions

THA-related nerve injury was found to be low at 0.35%. Factors independently associated with this adverse outcome were defined, of which the greatest risk was seen in revision procedures. These risk factors, derived from the largest cohort to date, may be helpful for risk stratification and patient counseling.

Elective THA for Indications Other Than Osteoarthritis Is Associated With Increased Cost and Resource Use: A Medicare Database Study of 135,194 Claims

BACKGROUND

Under Medicare's fee-for-service and bundled payment models, the basic unit of hospital payment for inpatient hospitalizations is determined by the Medicare Severity Diagnosis Related Group (MS-DRG) coding system. Primary total joint arthroplasties (hip and knee) are coded under MS-DRG code 469 for hospitalizations with a major complication or comorbidity and MS-DRG code 470 for those without a major complication or comorbidity. However, these codes do not account for the indication for surgery, which may influence the cost of care.Questions/purposes We sought to (1) quantify the differences in hospital costs associated with six of the most common diagnostic indications for THA (osteoarthritis, rheumatoid arthritis, avascular necrosis, hip dysplasia, posttraumatic arthritis, and conversion arthroplasty), (2) assess the primary drivers of cost variation using comparisons of hospital charge data for the diagnostic indications of interest, and (3) analyze the median length of stay, discharge destination, and intensive care unit use associated with these indications.

METHODS

This study used the 2019 Medicare Provider Analysis and Review Limited Data Set. Patients undergoing primary elective THA were identified using MS-DRG codes and International Classification of Diseases, Tenth Revision, Procedure Coding System codes. Exclusion criteria included non-fee-for-service hospitalizations, nonelective procedures, patients with missing data, and THAs performed for indications other than the six indications of interest. A total of 713,535 primary THAs and TKAs were identified in the dataset. After exclusions were applied, a total of 135,194 elective THAs were available for analysis. Hospital costs were estimated using cost-to-charge ratios calculated by the Centers for Medicare and Medicaid Services. The primary benefit of using cost-to-charge ratios was that it allowed us to analyze a large national dataset and to mitigate the random cost variation resulting from unique hospitals' practices and patient populations. As an investigation into matters of health policy, we believe that assessing the surgical cost borne by the "average" hospital was most appropriate. To analyze estimated hospital costs, we performed a multivariable generalized linear model controlling for patient demographics (gender, age, and race), preoperative health status, and hospital characteristics (hospital setting [urban versus rural], geography, size, resident-to-bed ratio, and wage index). We assessed the principal drivers of cost variation by analyzing the median hospital charges arising from 30 different hospital revenue centers using descriptive statistics. Length of stay, intensive care use, and discharge to a nonhome location were analyzed using multivariable binomial logistic regression.

RESULTS

The cost of THA for avascular necrosis was 1.050 times (95% confidence interval 1.042 to 1.069; p < 0.001), or 5% greater than, the cost of THA for osteoarthritis; the cost of hip dysplasia was 1.132 times (95% CI 1.113 to 1.152; p < 0.001), or 13% greater; the cost of posttraumatic arthritis was 1.220 times (95% CI 1.193 to 1.246; p < 0.001), or 22% greater; and the cost of conversion arthroplasty was 1.403 times (95% CI 1.386 to 1.419; p < 0.001), or 40% greater. Importantly, none of these CIs overlap, indicating a discernable hierarchy of cost associated with these diagnostic indications for surgery. Rheumatoid arthritis was not associated with an increase in cost. Medical or surgical supplies and operating room charges represented the greatest increase in charges for each of the surgical indications examined, suggesting that increased use of medical and surgical supplies and operating room resources were the primary drivers of increased cost. All of the orthopaedic conditions we investigated demonstrated increased odds that a patient would experience a prolonged length of stay and be discharged to a nonhome location compared with patients undergoing THA for osteoarthritis. Avascular necrosis, posttraumatic arthritis, and conversion arthroplasty were also associated with increased intensive care unit use. Posttraumatic arthritis and conversion arthroplasty demonstrated the largest increase in resource use among all the orthopaedic conditions analyzed.

CONCLUSION

Compared with THA for osteoarthritis, THA for avascular necrosis, hip dysplasia, posttraumatic arthritis, and conversion arthroplasty is independently associated with stepwise increases in resource use. These cost increases are predominantly driven by greater requirements for medical and surgical supplies and operating room resources. Posttraumatic arthritis and conversion arthroplasty demonstrated substantially increased costs, which can result in financial losses in the setting of fixed prospective payments. These findings underscore the inability of MS-DRG coding to adequately reflect the wide range of surgical complexity and resource use of primary THAs. Hospitals performing a high volume of THAs for indications other than osteoarthritis should budget for an anticipated increase in costs, and orthopaedic surgeons should advocate for improved MS-DRG coding to appropriately reimburse hospitals for the financial and clinical risk of these surgeries.

LEVEL OF EVIDENCE

Level IV, economic and decision analysis.

5-Factor Modified Frailty Index as a Predictor of Outcomes After Hemiarthroplasty or Total Hip Arthroplasty for Femoral Neck Fracture

INTRODUCTION

Although the 5-factor modified frailty index (mFI-5) has been shown to be an independent predictor of complications after primary total hip arthroplasty (THA), its predictive value has not been evaluated in the setting of hip fracture. We therefore assessed the utility of mFI-5 score as an independent predictor of morbidity and mortality in patients who underwent THA or hemiarthroplasty for femoral neck fracture.

METHODS

The American College of Surgeons National Surgical Quality Improvement database was queried for all patients with femoral neck fractures treated with THA or hemiarthroplasty between 2006 and 2020. A multivariate logistic regression analysis was done using mFI-5 as a predictor while controlling for baseline demographic and clinical variables.

RESULTS

In total, 45,185 patients (hemiarthroplasty: 37,645; THA: 7,540) were identified. For hemiarthroplasty patients, the mFI-5 strongly predicted risk of any complication (OR, 1.1; 95% CI, 1.1 to 1.2; P < 0.001), bleeding (OR, 1.2; 95% CI, 1.1 to 1.3; P < 0.001), and readmission (OR, 1.2; 95% CI, 1.1 to 1.3; P < 0.001). For THA patients, the mFI-5 was a strong predictor of any complication (OR, 1.2; 95% CI, 1.0 to 1.3; P = 0.023), pneumonia (OR, 1.4; 95% CI, 1.0 to 2.0; P = 0.047), and readmission (OR, 1.3; 95% CI, 1.1 to 1.6; P = 0.004).

DISCUSSION

The mFI-5 is an independent predictor of morbidity and complications after hemiarthroplasty and THA for femoral neck fracture. Importantly, readmission risk was predicted by the mFI-5. The mFI-5 may present a valuable clinical tool for assessment of high-risk patients who might require additional resources and specialized care after femoral neck fracture.

Cemented Versus Cementless Femoral Fixation for Total Hip Arthroplasty Following Osteoarthritis

BACKGROUND

The mode of femoral fixation for primary total hip arthroplasty (THA) is undetermined, with reported outcomes favoring different fixation methods. This study aimed to compare postoperative complications between cemented and cementless fixation at 90 days, 1 year, and 2 years in patients aged 65 years of age and older undergoing THA for osteoarthritis.

METHODS

Using an all-payer, national database, patients 65 years and older undergoing primary THA, either with cementless (n = 56,701) or cemented (n = 6,283) femoral fixation for osteoarthritis were identified. A 1:1 propensity-matched analysis for age, sex, comorbidity index, alcohol abuse, tobacco use, obesity, and diabetes was performed, resulting in n = 6,283 patients in each cohort. Postoperative outcomes, including postoperative periprosthetic joint infection, aseptic revision, surgical site infection, pulmonary embolism, venous thromboembolism, wound complications, dislocation, periprosthetic fracture, and aseptic loosening were assessed.

RESULTS

The cemented cohort had higher rates of infection (4.5 versus 0.8%, odds ratio [OR] 5.9, 95% confidence interval [CI] 4.33 to 7.93, P < .001), aseptic revision (2.9 versus 2.0%, OR 1.47, 95% CI 1.17 to 1.85, P = .001), venous thromboembolism (1.8 versus 1.3%, OR 1.40, 95% CI 1.05 to 1.87, P < .001), and aseptic loosening (1.5 versus 0.7%, OR 2.31, 95% CI 1.60 to 3.32, P < .001) at 90-days. At 1 and 2 years, the cemented cohort had higher rates of infection, aseptic revision, and aseptic loosening (all P < .001). Rates of periprosthetic fracture were similar at all time points (all P < .001).

CONCLUSIONS

Cemented fixation had higher rates of infection, aseptic loosening, and aseptic revision. This finding supports the current use of cementless fixation, but the ultimate decision regarding fixation type should be based on the proper optimization of the patient's comorbidities and bone quality.

Conversion THA With Concomitant Removal of Orthopaedic Hardware Should Be Reclassified as a Revision Surgery in the Medicare Severity Diagnosis-Related Group Coding Scheme: An Analysis of Cost and Resource Use

BACKGROUND

Conversion THA, which we defined for this study as THA with concomitant removal of preexisting orthopaedic hardware, has been associated with increased hospital costs and perioperative complications compared with primary THA. Yet, conversion THA is classified as a primary procedure under the Medicare Severity Diagnosis-Related Group coding scheme, and hospitals are reimbursed based on the resource use expected for a routine primary surgery. Prior authors have argued for conversion THA to be reclassified as a revision procedure. Although prior research has focused on comparisons between conversion THAs and primary arthroplasties, little is known about the resource use of conversion THA compared with that of revision THA.

QUESTIONS/PURPOSES

(1) Do inpatient hospital costs, estimated using cost-to-charge ratios, differ between conversion THA and revision THA? (2) Do the median length of stay, intensive care unit use, and likelihood of discharge to home differ between conversion and revision THA?

METHODS

This was a retrospective study of the Medicare Provider Analysis and Review Limited Data Set for 2019. A total of 713,535 primary and 74,791 revision THAs and TKAs were identified initially. Exclusion criteria then were applied; these included non-fee-for-service hospitalizations, nonelective admissions, and patients with missing data. Approximately 37% (263,545 of 713,535) of primary and 34% (25,530 of 74,791) of revision arthroplasties were excluded as non-fee-for-service hospitalizations. Two percent (13,159 of 713,535) of primaries and 11% (8159 of 74,791) of revisions were excluded because they were nonelective procedures. Among the remaining 436,831 primary and 41,102 revision procedures, 31% (136,748 of 436,831) were primary THAs and 36% (14,774 of 41,102) were revision THAs. Two percent (2761 of 136,748) of primary THAs involved intraoperative removal of hardware and were classified as conversion THAs. After claims with missing data were excluded, there were 2759 conversion THAs and 14,764 revision THAs available for analysis. Propensity scores were generated using a multivariate logistic regression model using the following variables as covariates: gender, age, race, van Walraven index, hospital setting, geography, hospital size, resident-to-bed ratio, and wage index. After matching, 2734 conversion THAs and 5294 revision THAs were available for analysis. The van Walraven index, which is a weighted score of patient preoperative comorbidities, was used to measure patient health status. Hospital costs were estimated by multiplying cost-to-charge ratios obtained from the 2019 Impact File by total hospital charges. This methodology enabled the use of a large national database to mitigate the random effects of individual hospitals' unique practices and patient populations. Multivariable regression was performed after matching to determine the independent effects of surgery type (that is, conversion versus revision THA) on hospital cost, length of stay greater than 2 days, intensive care unit use, and discharge to home.

RESULTS

There was no difference in the estimated hospital cost between conversion THA and revision THA (β = 0.96 [95% confidence interval 0.90 to 1.01]; p = 0.13). Patients undergoing conversion THA had increased odds of staying in the hospital for more than 2 days (odds ratio 1.12 [95% CI 1.03 to 1.23]; p = 0.01), increased odds of using the intensive care unit (OR 1.24 [95% CI 1.03 to 1.48]; p = 0.02), and decreased odds of being discharged to home (OR 0.74 [95% CI 0.67 to 0.80]; p < 0.001).

CONCLUSION

The inpatient hospital cost of conversion THA is no different from that of revision THA, although patients undergoing conversion surgery have modestly increased odds of prolonged length of stay, intensive care unit use, and discharge to a nonhome location. These findings support the conclusion that reclassification of conversion THA is warranted. Orthopaedic surgeons must advocate for the reclassification of conversion THA using data-backed evidence or run the risk that orthopaedic procedures will be given decreased reimbursement.

LEVEL OF EVIDENCE

Level III, economic and decision analysis.

Frailty Among Revision Total Knee Arthroplasty Recipients: Epidemiology and Propensity Score-weighted Analysis of Effect on In-hospital Postoperative Outcomes

BACKGROUND

Frailty has been shown to correlate with worse outcomes after total knee arthroplasty (TKA), although less is known regarding its effect on revision TKA (rTKA). This study examines the epidemiologic characteristics and inpatient outcomes of patients with frailty undergoing rTKA.

METHODS

Discharge data from National Inpatient Sample registry were used to identify all patients aged 50 years or older who underwent rTKA between 2006 and 2015. Patients were stratified into frail and nonfrail groupings, based on the presence of specific International Classification of Diseases-9 diagnostic coding. An analysis comparing the epidemiology, medical comorbidities, and propensity score-weighted postoperative clinical and economic outcomes of the two groups was done.

RESULTS

From 2006 to the third quarter of 2015, a total of 576,920 patients (17,727 frail) who underwent rTKA were included. The average age in the study's population was 67.2 years, with a female distribution of 57.4%. Frail patients were more likely to exhibit markedly higher rates of almost all modified Elixhauser Comorbities than their nonfrail counterparts. Frail patients were also more likely to undergo different types of revisions, including an increased rate of removal of the prosthesis without replacement. In addition, frail patients displayed increased likelihood of experiencing any postoperative complication, deep vein thrombosis, postoperative anemia, respiratory complications, and wound dehiscence. Frail patients experienced lower rates of discharge home and increased length of stay than the nonfrail cohort.

DISCUSSION

Patients with frailty undergoing rTKA are at markedly higher risk for inpatient postoperative complications and increased length of stay. Understanding the implications of frailty within rTKA is essential for risk assessment and preoperative optimization for this expanding population.

Age-Adjusted Modified Frailty Index: Association With Hip Fracture Discharge Functional Dependence

INTRODUCTION

Hip fractures are a common traumatic injury that carry significant morbidity and mortality, and prognostication of functional outcome is becoming increasingly salient. Across multiple surgical specialties, the five-item and 11-item Modified Frailty Index (mFI-5 and mFI-11) have been found to be convenient, quick, and sensitive tools for identifying patients at risk for perioperative complications. A prior study described the superiority of an Age-Adjusted Modified Frailty Index (aamFI) for predicting perioperative complications compared to the mFI-5 in an elective hip surgery. We sought to externally validate the aamFI in a multicenter hip fracture cohort and hypothesize that these risk scores would not only predict functional dependence (FD) at discharge, but that the aamFI would outperform the mFI-5 and mFI-11.

METHODS

The Pennsylvania Trauma Systems Foundation registry was queried from 2010 to 2020 for CPT codes, ICD-9 and ICD-10 codes pertaining to hip fracture patients. Patients with missing locomotion and transfer mobility data were excluded. FD status was determined by discharge locomotion and transfer mobility scores per existing methodology. Univariable and Multivariable analysis as well as receiver operator characteristic curves were used to evaluate and compare the three indices for prediction of functional status at discharge. P value < 0.05 was considered significant.

RESULTS

Twelve thousand seven hundred and forty patients met inclusion criteria (FD: 8183; functional independent 4557). On univariable logistic regression analysis, the mFI-11 (odds ratio [OR] 1.52, 95% confidence interval [CI] 1.47-1.58, P < 0.05), mFI-5 (OR 1.57, 95% CI 1.51-1.63), and aamFI (OR 1.57, 95% CI 1.52-1.62, P < 0.05) were associated with FD. On multivariable logistic regression analysis for predictors of FD, when controlling for age (for the mFI-11 and mFI-5), sex, injury severity score, and admission vitals (systolic blood pressure and respiratory rate), higher mFI-11 and mFI-5 scores independently predicted FD at discharge (OR 1.23, 95% CI 1.18-1.28, P < 0.05 and OR 1.23, 95% CI 1.18-1.29P < 0.05 respectively). Higher aaMFI scores had superior association with functional dependence (OR 1.59, 95% CI 1.54-1.64, P < 0.05). Receiver operator characteristic curves for the mFI-11, mFI-5, and aaMFI showed comparable diagnostic strength (area under curve [AUC] = 0.63 95% CI 0.62-0.64, P < 0.05; AUC = 0.63 95% CI 0.62-0.64, P < 0.05; and AUC = 0.67 95% CI 0.65-0.67, P < 0.05 respectively).

CONCLUSIONS

The mFI-11, mFI-5, and aamFI are predictive of functional outcome following hip fracture. By including age, the aamFI retains the ease of use of the mFI-5 while improving its prognostic utility for functional outcome.

An evaluation of three validated comorbidity indices to predict short-term postoperative outcomes after prosthetic urologic surgery

PURPOSE

Commonly used comorbidity indices include the Charlson Comorbidity Index (CCI), Elixhauser/Van Walraven Index (VWI), and modified frailty index (mFI). This study evaluates whether these indices predict postoperative readmissions and complications after inflatable penile prosthesis (IPP) and artificial urinary sphincter (AUS) placement.

METHODS

We identified adult males who underwent IPP or AUS placement using the State Inpatient and State Ambulatory Surgery and Services Databases for Florida (2010-2015) and California (2010-2011). CCI, VWI, and mFI scores were calculated for each patient. We extracted 30-day emergency department services, 30-day readmissions, 90-day device complications (e.g., removal, replacement, or infection), and 90-day postoperative complications (excluding device complications). Receiver-operating characteristic curves were constructed and areas under the curve (AUC) were compared between the indices using the VWI as the reference model. We considered an AUC < 0.7 to represent poor predictive power.

RESULTS

We identified 4242 IPP and 1190 AUS patients. All three indices had AUCs and 95% confidence intervals less than 0.70 for all outcomes following IPP and AUS placement making these indices poor predictors for postoperative outcomes. There were no significant differences in predicting 90-day postoperative complications between the VWI (AUC = 0.59, 95% CI [0.54-0.63]), CCI (AUC = 0.59, 95% CI [0.54-0.63], p = 0.99), and mFI (AUC = 0.60, 95% CI [0.55-0.66], p = 0.53) for IPPs and VWI (AUC = 0.54, 95% CI [0.47-0.61]), CCI (AUC = 0.50, 95% CI [0.43-0.57], p = 0.30), and mFI (AUC = 0.52, 95% CI [0.43-0.60], p = 0.56) for AUS placements.

CONCLUSION

All three comorbidity indices were poor predictors of readmissions and complications following urologic prosthetic surgeries. A better comorbidity index is needed for risk-stratification of patients undergoing these surgeries.

Inferior Outcomes for Patients Transferred Between Surgical Stages for Knee Periprosthetic Joint Infection

BACKGROUND

Periprosthetic joint infection (PJI) in total knee arthroplasty may result in 2-stage revision surgery. There are limited data describing outcomes when the first stage is completed at an outside hospital and the patient is referred to a tertiary center. We hypothesized that patients have greater success when both surgeries occur at a single center.

METHODS

There were 25 knee PJI patients who presented with an antibiotic spacer and had a minimum 2-year follow-up who were retrospectively identified at a single tertiary referral center from 2014 to 2021. A cohort matched for age, sex, body mass index, Elixhauser comorbidity measure, spacer type, infectious organism, and year of surgery was established with patients who had both stages completed at the investigating institution. Modified Delphi success criteria of no subsequent surgery or reinfection with any species were compared.

RESULTS

The transferred group demonstrated a treatment success of 40% compared to 84% in the continuous group (P < .01). The transferred group was more likely to have an additional procedure between stages (44 versus 8%, P < .01), with a higher number of surgeries after primary total knee arthroplasty (4.8 versus 3.0, P < .01), between stages (1.4 versus 0.2, P < .01), and after second stage (0.8 versus 0.2, P = .03). The transferred group had longer durations between stages (20.1 versus 7.0 weeks, P < .01).

CONCLUSION

Patients who have PJIs transferred between stages demonstrated higher treatment failure. Surgeons should consider transfer early with a goal of continuous management by a single institution.

Bisphosphonate Use May be Associated With an Increased Risk of Periprosthetic Hip Fracture

BACKGROUND

Osteoporosis is common among patients undergoing primary total hip arthroplasty (THA). This study aimed to evaluate the effect of bisphosphonate treatment on osteoporotic patients undergoing primary THA.

METHODS

Using a national database, 30,137 patients who had osteoporosis before primary elective THA were identified during 2010 to 2020. Patients undergoing nonelective THA and those using corticosteroids or other medications for osteoporosis were excluded. Bisphosphonate users and bisphosphonate naïve patients were matched 1:1 based on age, sex, Elixhauser comorbidity index, and a history of obesity, rheumatoid arthritis, tobacco use, and alcohol abuse. Kaplan-Meier and multivariate analyses were used to compare 2-year outcomes between groups.

RESULTS

Among matched cohorts of 9,844 patients undergoing primary THA, bisphosphonate use was associated with a significantly higher 2-year rate of periprosthetic fracture (odds ratio 1.29, 95% confidence interval 1.04 to 1.61, P = .022). There was a trend toward increased risk of any revision with bisphosphonate use (odds ratio 1.19, confidence interval 1.00 to 1.41, P = .056). Rates of infection, aseptic loosening, dislocation, and mortality were not statistically different between bisphosphonate users and bisphosphonate-naïve patients.

CONCLUSION

In osteoporotic patients, bisphosphonate use before primary THA is an independent risk factor for periprosthetic fracture. Additional longer-term data are needed to determine the underlying mechanism for this association and identify preventative measures.

What Are the Differences in Hospital Cost Associated With the Use of Cemented Versus Cementless Femoral Stems in Hemiarthroplasty and Total Hip Arthroplasty for the Treatment of Femoral Neck Fracture?

BACKGROUND

The purpose of this study was to determine if there is a difference in hospital costs associated with the use of cemented versus cementless femoral stems in hemiarthroplasty (HA) and total hip arthroplasty (THA) for the treatment of femoral neck fracture (FNF).

METHODS

This retrospective cohort study utilizes the 2019 Medicare Provider Analysis and Review Limited Data Set. Patients undergoing arthroplasty for the treatment of FNF were identified. Patients were grouped by cemented or cementless femoral stem fixation. There were 16,148 patients who underwent arthroplasty for FNF available: 4,913 THAs (3,705 patients who had cementless femoral stems and 1,208 patients who had cemented femoral stems) and 11,235 HAs (6,099 patients who had cementless femoral stems and 5,136 who had cemented femoral stems). Index hospital costs were estimated by multiplying total charges by cost-to-charge ratios. Costs were analyzed using univariable and multivariable generalized linear models.

RESULTS

Cemented femoral stem THA generated 1.080 times (95% confidence interval, 1.06 to 1.10; P < .001), or 8.0%, greater index hospital costs than cementless femoral stem THA, and cemented femoral stem HA generated 1.042 times (95% confidence interval, 1.03 to 1.05; P < .001), or 4.2%, greater index hospital costs than cementless femoral stem HA.

CONCLUSIONS

Cemented femoral stems for FNF treated with either THA or HA are associated with only a small portion of increased cost compared to cementless femoral stems. Providers may choose the method of arthroplasty stem fixation for the treatment of FNF based on what they deem most appropriate for the specific patient.

Trends in deep vein thrombosis prophylaxis after total hip arthroplasty: 2016 to 2021

Introduction

Venous thromboembolism (VTE) has long been acknowledged as a potential complication of total hip arthroplasty (THA) contributing to heightened patient morbidity, mortality, and substantial healthcare costs. We aimed to: 1) assess trends in VTE prophylaxis utilization between 2016 and 2021; 2) determine the incidence of postoperative VTE and transfusions; and 3) identify independent risk factors for 90-day VTE and transfusion risks following THA in relation to the use of aspirin, dabigatran, enoxaparin, rivaroxaban, and warfarin.

Methods

A national, all-payer database was queried from January 1, 2016 and December 31, 2022. Use trends for aspirin, enoxaparin, rivaroxaban, dabigatran, and warfarin as thromboprophylaxis following THA was assessed. Incidence of ninety-day postoperative outcomes assessed included rates of 90-day postoperative VTE and transfusion.

Results

From 2016 to 2021, aspirin (n = 36,346) was the most used agent for VTE prophylaxis after THA, followed by dabigatran (n = 13,065), rivaroxaban (n = 11,790), enoxaparin (n = 11,380), and warfarin (n = 6326). Independent risk factors for 90-day VTE included CKD, COPD, CHF, obesity, dabigatran, enoxaparin, rivaroxaban, and warfarin (all p < 0.05).

Conclusion

Aspirin was used with increasing frequency and demonstrated lower rates of VTE and transfusion following THA, compared to dabigatran, enoxaparin, rivaroxaban, and warfarin. These findings seem to indicate that the increasing use of aspirin in VTE prophylaxis has been accomplished in appropriately selected patients.

Social determinants of health in patients undergoing hemiarthroplasty: are they associated with medical complications, healthcare utilization, and payments for care?

INTRODUCTION

Social determinants of health (SDOH) have previously been shown to impact orthopedic surgery outcomes. This study assessed whether greater socioeconomic disadvantage in patients undergoing hemiarthroplasty following femoral neck fracture was associated with differences in (1) medical complications, (2) emergency department (ED) utilization, (3) readmission rates, and (4) payments for care.

METHODS

A US nationwide database was queried for hemiarthroplasties performed between 2010 and 2020. Area Deprivation Index (ADI), a validated measure of socioeconomic disadvantage reported on a scale of 0-100, was used to compare two cohorts of greater and lesser deprivation. Patients undergoing hemiarthroplasty from high ADI (95% +) were 1:1 propensity score matched to a comparison group of lower ADI (0-94%) while controlling for age, sex, and Elixhauser Comorbidity Index. This yielded 75,650 patients evenly distributed between the two cohorts. Outcomes studied were 90-day medical complications, ED utilizations, readmissions, and payments for care. Multivariate logistic regression models were utilized to calculate odds ratios (ORs) of the relationship between ADI and outcomes. p Values < 0.05 were significant.

RESULTS

Patients of high ADI developed greater medical complications (46.74% vs. 44.97%; OR 1.05, p = 0.002), including surgical site infections (1.19% vs. 1.00%; OR 1.20, p = 0.011), cerebrovascular accidents (1.64% vs. 1.41%; OR 1.16, p = 0.012), and respiratory failures (2.27% vs. 2.02%; OR 1.13, p = 0.017) compared to patients from lower ADIs. Although comparable rates of ED visits (2.92% vs. 2.86%; OR 1.02, p = 0.579), patients from higher ADI were readmitted at diminished rates (10.57% vs. 11.06%; OR 0.95, p = 0.027). Payments were significantly higher on the day of surgery ($7,570 vs. $5,974, p < 0.0001), as well as within 90 days after surgery ($12,700 vs. $10,462, p < 0.0001).

CONCLUSIONS

Socioeconomically disadvantaged patients experience increased 90-day medical complications and payments, similar ED utilizations, and decreased readmissions. These findings can be used to inform healthcare providers to minimize disparities in care.

LEVEL OF EVIDENCE

III.

Decreasing trend of inpatient mortality rates of aseptic versus septic revision total hip arthroplasty: an analysis of 681,034 cases

BACKGROUND

While most revision total hip arthroplasties (rTHAs) are for aseptic loosening/instability, infection accounts for approximately 16%. The purpose of this study was to: (1) quantify mortality rates of aseptic versus septic rTHA; (2) determine if mortality rates have changed over the past 20 years; and (3) identify associated preoperative risk factors, focusing on the utility/validity of the Elixhauser comorbidity index (ECI).

METHODS

ICD-9/ICD-10 codes were used to identify patients undergoing rTHA in the National Inpatient Sample database between 1998 and 2017. A total of 681,034 cases (576,143 aseptic THA and 104,891 septic THA) were identified. For each patient, demographic variables including age, sex, race, insurance type, ECI, and inhospital mortality were gathered. A logistic regression model was constructed to assess risk of inhospital mortality.

RESULTS

From 1998 to 2017, inpatient mortality rates of aseptic and septic rTHA decreased from 0.83 to 0.45%, and from 2.58 to 1.24%, respectively. Septic rTHA was independently associated with higher odds of mortality relative to aseptic (odds ratio (OR): 2.305, 95% confidence interval (CI): (2.014, 2.638), p < 0.0001). Increased ECI was associated with higher odds of mortality at both medium (OR: 5.147, 95% CI: (4.433,5.977), p < 0.0001) and high index scores (OR: 13.714, 95% CI: (11.519,16.326), p < 0.0001).

CONCLUSIONS

Mortality rates for both aseptic and septic rTHA have been declining over the past 20 years, potentially due to patient selection guidelines and advances in medical management. Our study confirms that the ECI is independently associated with increased inpatient mortality.

A systematic review of predictive accuracy via c-statistic of preoperative frailty tests for extended length of stay, post-operative complications, and mortality

Frailty, as an age-related syndrome of reduced physiological reserve, contributes significantly to post-operative outcomes. With the aging population, frailty poses a significant threat to patients and health systems. Since 2012, preoperative frailty assessment has been recommended, yet its implementation has been inhibited by the vast number of frailty tests and lack of consensus. Since the anesthesiologist is the best placed for perioperative care, an anesthesia-tailored preoperative frailty test must be simple, quick, universally applicable to all surgeries, accurate, and ideally available in an app or online form. This systematic review attempted to rank frailty tests by predictive accuracy using the c-statistic in the outcomes of extended length of stay, 3-month post-operative complications, and 3-month mortality, as well as feasibility outcomes including time to completion, equipment and training requirements, cost, and database compatibility. Presenting findings of all frailty tests as a future reference for anesthesiologists, Clinical Frailty Scale was found to have the best combination of accuracy and feasibility for mortality with speed of completion and phone app availability; Edmonton Frailty Scale had the best accuracy for post-operative complications with opportunity for self-reporting. Finally, extended length of stay had too little data for recommendation of a frailty test. This review also demonstrated the need for changing research emphasis from odds ratios to metrics that measure the accuracy of a test itself, such as the c-statistic.

High-volume Arthroplasty Centers Are Associated With Lower Hospital Costs When Performing Primary THA and TKA: A Database Study of 288,909 Medicare Claims for Procedures Performed in 2019

BACKGROUND

With bundled payments and alternative reimbursement models expanding in scope and scale, reimbursements to hospitals are declining in value. As a result, cost reduction at the hospital level is paramount for the sustainability of profitable inpatient arthroplasty practices. Although multiple prior studies have investigated cost variation in arthroplasty surgery, it is unknown whether contemporary inpatient arthroplasty practices benefit from economies of scale after accounting for hospital characteristics and patient selection factors. Quantifying the independent effects of volume-based cost variation may be important for guiding future value-based health reform.

QUESTIONS/PURPOSES

We performed this study to (1) determine whether the cost incurred by hospitals for performing primary inpatient THA and TKA is independently associated with hospital volume and (2) establish whether length of stay and discharge to home are associated with hospital volume.

METHODS

The primary data source for this study was the Medicare Provider Analysis and Review Limited Data Set, which includes claims data for 100% of inpatient Medicare hospitalizations. We included patients undergoing primary elective inpatient THA and TKA in 2019. Exclusion criteria included non-Inpatient Prospective Payment System hospitalizations, nonelective admissions, bilateral procedures, and patients with cancer of the pelvis or lower extremities. A total of 500,658 arthroplasties were performed across 2762 hospitals for 492,262 Medicare beneficiaries during the study period; 59% (288,909 of 492,262) of procedures were analyzed after the exclusion criteria were applied. Most exclusions (37% [182,733 of 492,262]) were because of non-Inpatient Prospective Payment System hospitalizations. Among the study group, 87% (251,996 of 288,909) of procedures were in patients who were 65 to 84 years old, 88% (255,415 of 288,909) were performed in patients who were White, and 63% (180,688 of 288,909) were in patients who were women. Elixhauser comorbidities and van Walraven indices were calculated as measures of patient health status. Hospital costs were estimated by multiplying cost-to-charge ratios obtained from the 2019 Impact File by total hospital charges. This methodology enabled us to use the large Medicare Provider Analysis and Review database, which helped decrease the influence of random cost variation through the law of large numbers. Hospital volumes were calculated by stratifying claims by national provider identification number and counting the number of claims per national provider identification number. The data were then grouped into bins of increasing hospital volume to more easily compare larger-volume and smaller-volume centers. The relationship between hospital costs and volume was analyzed using univariable and multivariable generalized linear models. Results are reported as exponential coefficients, which can be interpreted as relative differences in cost. The impact of surgical volume on length of stay and discharge to home was assessed using binary logistic regression, considering the nested structure of the data, and results are reported as odds ratios (OR).

RESULTS

Hospital cost and mean length of stay decreased, while rates of discharge to home increased with increasing hospital volume. After controlling for potential confounding variables such as patient demographics, health status, and geographic location, we found that inpatient arthroplasty costs at hospitals with 10 or fewer, 11 to 100, and 101 to 200 procedures annually were 1.32 (95% confidence interval [CI] 1.30 to 1.34; p < 0.001), 1.17 (95% CI 1.17 to 1.17; p < 0.001), and 1.10 (95% CI 1.10 to 1.10; p < 0.001) times greater than those of hospitals with 201 or more inpatient procedures annually. In addition, patients treated at smaller-volume hospitals had increased odds of experiencing a length of stay longer than 2 days (OR 1.25 to 3.44 [95% CI 1.10 to 4.03]; p < 0.001) and decreased odds of being discharged to home (OR 0.34 to 0.78 [95% CI 0.29 to 0.86]; p < 0.001).

CONCLUSION

Higher-volume hospitals incur lower costs, shorter lengths of stay, and higher rates of discharge to home than lower-volume hospitals when performing inpatient THA and TKA. These findings suggest that small and medium-sized regional hospitals are disproportionately impacted by declining reimbursement and may necessitate special treatment to remain viable as bundled payment models continue to erode hospital payments. Further research is also warranted to identify the key drivers of this volume-based cost variation, which may facilitate quality improvement initiatives at the hospital and policy levels.

Epidemiology of primary and revision total knee arthroplasty: analysis of demographics, comorbidities and outcomes from the national inpatient sample

INTRODUCTION

Primary total knee arthroplasty (TKA) is a preferred treatment for end-stage knee osteoarthritis. In the setting of a failed TKA, revision total knee arthroplasty (rTKA) acts as a salvage procedure and carries a higher risk compared to primary TKA. Given increased interest in postoperative outcomes from these procedures, a thorough understanding of the demographics, comorbidities, and inpatient outcomes is warranted. This study aimed to report the epidemiological data of demographics, comorbidity profiles and outcomes of patients undergoing TKA and rTKA.

METHODS

A retrospective review of NIS registry discharge data from 2006 to 2015 third quarter was performed. This study included adults aged 40 and older who underwent TKA or rTKA. A total of 5,901,057 TKA patients and 465,968 rTKA patients were included in this study. Simple descriptive statistics were used to present variables on demographics, medical comorbidities, and postoperative complications.

RESULTS

A total of 5,901,057 TKA and 465,968 rTKA discharges were included in this study, with an average age of 66.30 and 66.56 years, and the major payor being Medicare, accounting for 55.34% and 59.88% of TKA and rTKA cases, respectively. Infection (24.62%) was the most frequent reason for rTKA, and was followed by mechanical complications (18.62%) and dislocation (7.67%). The most common medical comorbidities for both groups were hypertension, obesity, and diabetes. All types of inpatient complications were reported in 22.21% TKA and 28.78% of rTKA cases. Postoperative anemia was the most common complication in both groups (20.34% vs. 25.05%).

CONCLUSIONS

Our data demonstrated a 41.9% increase in patients receiving TKA and 28.8% increase in rTKA from the years 2006 to 2014. The data showed a 22.21% and a 28.78% "complication" rate with TKA and rTKA, with postoperative anemia being the most common complication. The top 3 medical comorbidities were hypertension, obesity, and diabetes for both groups and with increased focus on perioperative optimization, future analyses into preoperative medical optimization, and improved primary arthroplasty protocol may result in improved postoperative outcomes.

Frailty Among Total Hip and Knee Arthroplasty Recipients: Epidemiology and Propensity Score-weighted Analysis of Effect on In-hospital Postoperative Outcomes

INTRODUCTION

Total joint arthroplasty (TJA) is one of the most successful and frequently performed procedures in the United States. The number of these procedures is projected to continue growing rapidly in the coming years, and with it comes the demand for more sophisticated perioperative risk and complication assessment. This study examines the effect of frailty on postoperative inpatient complications and hospital resource utilization after TJA.

METHODS

Discharge data from the National Inpatient Sample were used to identify all patients aged 50 years or older who underwent TJA between 2006 and 2015. Nonelective admissions and hip fractures were excluded. Patients were stratified into two groups with and without concomitant ICD-9 diagnostic criteria that qualified them has having frailty. An analysis comparing the 2 groups' epidemiology, medical comorbidities, and propensity score-weighted postoperative clinical and economic outcomes was done.

RESULTS

A total of 7,854,890 TJAs were included in this analysis, with 136,516 meeting the criteria for frailty and 7,718,374 being nonfrail. Among these patients, the average age was 67.3 years and the female distribution was 61.1%. Frail patients were found to have markedly higher rates of all but two individual comorbidities constituting the Modified Elixhauser Profile compared with nonfrail patients. Compared with the control group, frail patients were found to have increased risk of any postoperative complication, central nervous system complications, hematoma/seroma, wound dehiscence, infection, and postoperative anemia. Frail patients also had longer length of stay, higher discharge to rehabilitation facilities, and higher hospital charges.

DISCUSSION

Patients with frailty undergoing TJA procedures are at a markedly higher risk for developing postoperative complications and worse hospital economic outcomes. As this patient population continues to increase, it is imperative for clinicians to use their risk factors in optimizing their perioperative care and support.

Opioid prescription trends after ambulatory anterior cervical discectomy and fusion

BACKGROUND CONTEXT

Opioid utilization has been well studied for inpatient anterior cervical discectomy and fusion (ACDF). However, the amount and type of opioids prescribed following ambulatory ACDF and the associated risk of persistent use are largely unknown.

PURPOSE

To characterize opioid prescription filling following single-level ambulatory ACDF compared with inpatient procedures.

STUDY DESIGN/SETTING

Retrospective cohort study.

PATIENT SAMPLE

Opioid-naive patients who underwent ambulatory (no overnight stay) or inpatient single-level ACDF from 2011 to 2019 were identified from a national insurance database.

OUTCOME MEASURES

Rate, amount, and type of perioperative opioid prescription.

METHODS

Opioid-naive patients who underwent ambulatory (no overnight stay) or inpatient single-level ACDF from 2011 to 2019 were identified from a national insurance database. Perioperative opioids were defined as opioid prescriptions 30 days before and 14 days after the procedure. Rate, amount, and type of opioid prescription were characterized. Multivariable analyses controlling for any differences in demographics and comorbidities between the two treatment groups were utilized to determine any association between surgical setting and persistent opioid use (defined as the patient still filling new opioid prescriptions >90 days postoperatively).

RESULTS

A total of 42,521 opioid-naive patients were identified, of which 2,850 were ambulatory and 39,671 were inpatient. Ambulatory ACDF was associated with slightly increased perioperative opioid prescription filling (52.7% vs 47.3% for inpatient procedures; p<.001). Among the 20,280 patients (47.7%) who filled perioperative opioid prescriptions, the average amount of opioids prescribed (in morphine milligram equivalents) was similar between ambulatory and inpatient procedures (550 vs 540, p=.413). There was no association between surgical setting and persistent opioid use in patients who filled a perioperative opioid prescription, even after controlling for comorbidities, (adjusted odds ratio, 1.15, p=.066).

CONCLUSIONS

Ambulatory ACDF patients who filled perioperative opioid prescriptions were prescribed a similar amount of opioids as those undergoing inpatient procedures. Further, ambulatory ACDF does not appear to be a risk factor for persistent opioid use. These findings are important for patient counseling as well as support the safety profile of this new surgical pathway.

Can extant comorbidity indices identify patients who experience poor outcomes following total joint arthroplasty?

INTRODUCTION

It is uncertain if generic comorbidity indices commonly used in orthopedics accurately predict outcomes after total hip (THA) or knee arthroplasty (TKA). The purpose of this study was to determine the predictive ability of such comorbidity indices for: (1) 30-day mortality; (2) 30-day rate of major and minor complications; (3) discharge disposition; and (4) extended length of stay (LOS).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was retrospectively reviewed for all patients who underwent elective THA (n = 202,488) or TKA (n = 230,823) from 2011 to 2019. The American Society of Anesthesiologists (ASA) physical status classification system score, modified Charlson Comorbidity Index (mCCI), Elixhauser Comorbidity Measure (ECM), and 5-Factor Modified Frailty Index (mFI-5) were calculated for each patient. Logistic regression models predicting 30-day mortality, discharge disposition, LOS greater than 1 day, and 30-day major and minor complications were fit for each index.

RESULTS

The ASA classification (C-statistic = 0.773 for THA and TKA) and mCCI (THA: c-statistic = 0.781; TKA: C-statistic = 0.771) were good models for predicting 30-day mortality. However, ASA and mCCI were not predictive of major and minor complications, discharge disposition, or LOS. The ECM and mFI-5 did not reliably predict any outcomes of interest.

CONCLUSION

ASA and mCCI are good models for predicting 30-day mortality after THA and TKA. However, similar to ECM and mFI-5, these generic comorbidity risk-assessment tools do not adequately predict 30-day postoperative outcomes or in-hospital metrics. This highlights the need for an updated, data-driven approach for standardized comorbidity reporting and risk assessment in arthroplasty.

Comorbidity, Racial, and Socioeconomic Disparities in Total Knee and Hip Arthroplasty at High Versus Low-Volume Centers

INTRODUCTION

The purpose of this study was to compare the epidemiologic and demographic profiles and inpatient postoperative complication and economic outcomes of patients undergoing total joint arthroplasty of the hip and knee (TJA) at high-volume centers (HVCs) versus low-volume centers (LVCs) using a large national registry.

METHODS

This retrospective cohort study used data from the National Inpatient Sample from 2006 to the third quarter of 2015. Discharges representing patients aged 40 years or older receiving a primary total hip arthroplasty or total knee arthroplasty were included. Patients were stratified into those undergoing their procedure at HVCs versus LVCs. Epidemiologic, demographic, and inpatient postoperative complications and economic outcomes were comparatively analyzed between groups.

RESULTS

A total of 7,694,331 TJAs were conducted at HVCs while 1,044,358 were conducted at LVCs. Patients at LVCs were more likely to be female, be Hispanic, be non-Hispanic Black, and use Medicare and Medicaid than patients at HVCs. Of the 29 Elixhauser comorbidities examined, 14 were markedly higher at LVCs while 11 were markedly higher at HVCs. Patients who underwent TJA at LVCs were more likely to develop cardiac, respiratory, gastrointestinal, genitourinary, hematoma/seroma, wound dehiscence, and postoperative infection complications and were more likely to die during hospitalization. Patients at HVCs were more likely to develop postoperative anemia. Length of stay and total charges were higher at LVCs compared with HVCs.

DISCUSSION

There are notable differences in the demographics, epidemiologic characteristics, and inpatient outcomes of patients undergoing TJA at HVCs versus LVCs. Attention should be directed to identifying and applying the specific resources, processes, and practices that improve outcomes at HVCs while referral practices and centralization efforts should be mindful to not worsen already existing disparities.

Cannabis use disorder is associated with shorter length of stay and increased home discharge after primary total joint arthroplasty: a propensity-weighted analysis

INTRODUCTION

Increased legalization of cannabis use across the United States has been correlated with increased cannabis use in the clinical setting. However, little is known regarding the characteristics and postoperative outcomes after primary joint arthroplasty (TJA) for patients with cannabis use disorder (CUD).

METHODS

This retrospective cohort study used data from the National Inpatient Sample of patients undergoing primary TJA between 2006 to 2015. Patients were grouped based on presence of concomitant CUD. Patient demographic characteristics and outcome data between groups were analyzed. Propensity score methodology was used to compare immediate in-hospital complications and economic outcomes.

RESULTS

A total of 8,740,798 TJAs were included. The prevalence of CUD increased nearly five-fold from 0.05% to 0.26% during this time (P < 0.0001). CUD patients were significantly younger, more likely to be male, most frequently of non-Hispanic Black race, and had higher rates of Medicaid insurance. Patients with CUD had a significantly shorter length of hospital stay (3.04 vs. 3.24 days, P = 0.0297), while incurring significantly higher daily ($22,614 vs. $17,955, P < 0.0001) and total charges during admission ($58,507 vs. $50,924, P < 0.0001), compared to patients without CUD. When compared with the control group, CUD was associated with significantly greater odds of home discharge (odds ratio (OR): 1.45, P = 0.0007), and significantly lower odds of rehab discharge (OR: 0.70, P = 0.0013). There were no differences in overall complication profile or in the vast majority of individual in-hospital complications between groups.

CONCLUSION

While CUD is correlated to shorter length of stay and increased home discharge after TJA, it does not show a strong effect on complications in an inpatient postoperative setting. It is important for clinicians to appreciate the demographic profile and expected clinical and economic outcomes for patients with CUD undergoing TJA, particularly in the context of evolving laws surrounding cannabis use.

Comparison of general and regional anesthesia on short-term complications in patients undergoing total knee arthroplasty: A retrospective study using national health insurance service-national sample cohort

This retrospective study compared the mortality and short-term complications according to the choice of general anesthesia or regional anesthesia in patients who underwent a total knee arthroplasty (TKA). We searched the Korean National Health Insurance Service National Sample Cohort database to analyze data from patients who received a TKA between January 2002 and December 2015. Before comparing the general and the regional anesthesia groups, the bias was reduced by propensity score matching. After matching, the mortality and complications occurring within 30 days after a TKA were compared between the 2 groups. In the database, 6491 primary TKA cases were identified. Nine hundred forty-three patients (14.5%) had a TKA performed under general anesthesia, and 5548 (85.5%) had a TKA performed under regional anesthesia. After propensity score matching, the data of 1886 patients were analyzed, with 943 patients in each group. There was no significant difference in mortality (0.32% vs 0.00%), transfusion rate (84.52% vs 84.73%, P = .8989), and length of hospital stay (50 vs 53, P = .5391) between the general and regional anesthesia groups. Most of the complications were not significantly different, but the major complications, including myocardial infarction (1.70% vs 0.64%, P = .0414) and acute renal failure (0.85% vs 0.11%, P = .0391), were higher in the general anesthesia group than in the regional anesthesia group. Also, admission to the intensive care unit (8.48% vs 2.33%, P < .0001) and total cost (₩8067, 400 vs ₩7487, 940, P = .0002) were higher in the general anesthesia group than in the regional anesthesia group. Our study found that regional anesthesia for TKA is associated with a decrease in major complications, including myocardial infarction and acute renal failure, and medical costs.

Epidemiology of total hip arthroplasty: demographics, comorbidities and outcomes

BACKGROUND

Primary THA (THA) is a successful procedure for end-stage hip osteoarthritis. In the setting of a failed THA, revision total hip arthroplasty (rTHA) acts as a salvage procedure. This procedure has increased risks, including sepsis, infection, prolonged surgery time, blood loss, and increased length of stay. Increasing focus on understanding of demographics, comorbidities, and inpatient outcomes can lead to better perioperative optimization and post-operative outcomes. This epidemiological registry study aimed to compare the demographics, comorbidity profiles, and outcomes of patients undergoing THA and rTHA.

METHODS

A retrospective review of discharge data reported from 2006 to the third quarter of 2015 using the National Inpatient Sample registry was performed. The study included adult patients aged 40 and older who underwent either THA or rTHA. A total of 2,838,742 THA patients and 400,974 rTHA patients were identified.

RESULTS

The primary reimbursement for both THA and rTHA was dispensed by Medicare at 53.51% and 65.36% of cases respectively. Complications arose in 27.32% of THA and 39.46% of rTHA cases. Postoperative anemia was the most common complication in groups (25.20% and 35.69%). Common comorbidities in both groups were hypertension and chronic pulmonary disease. rTHA indications included dislocation/instability (21.85%) followed by mechanical loosening (19.74%), other mechanical complications (17.38%), and infection (15.10%).

CONCLUSION

Our data demonstrated a 69.50% increase in patients receiving THA and a 28.50% increase in rTHA from the years 2006 to 2014. The data demonstrated 27.32% and 39.46% complication rate with THA and rTHA, with postoperative anemia as the most common cause. Common comorbidities were hypertension and chronic pulmonary disease. Future analyses into preoperative optimizations, such as prior consultation with medical specialists or improved primary hip protocol, should be considered to prevent/reduce postoperative complications amongst a progressive expansion in patients receiving both THA and rTHA.

Use of a Six-Item Modified Frailty Index to Predict 30-day Adverse Events, Readmission, and Mortality in Older Patients Undergoing Surgical Fixation of Lower Extremity, Pelvic, and Acetabular Fractures

INTRODUCTION

This is a retrospective study evaluating the use of a new six-item modified frailty index (MF-6) to predict short-term outcomes of patients receiving surgery for lower extremity fractures.

METHODS

Patients older than 65 years undergoing open reduction and internal fixation for lower extremity, pelvic, and acetabulum fractures were identified from the American College of Surgeons National Surgical Quality Improvement Program. The MF-6 was calculated by assigning one point for each of six common conditions. Multivariable analysis was used to compare patients with an MF-6 of <3 and ≥3. Outcome measures included complications, mortality, readmission, revision surgery, and length of stay. An area under the curve receiver operator analysis was conducted to compare the MF-6 with MF-5, an existing five-item frailty index.

RESULTS

Nine thousand four hundred sixty-three patients were included. Patients with an MF-6 of ≥3 were at markedly higher risk of discharge destination other than home (Exp[B] = 2.09), mortality (Exp[B] = 2.48), major adverse events (Exp[B] = 2.16), and readmission (Exp[B] = 1.82). Receiver-operating curve analysis demonstrated an area under the curve of 0.65 for mortality, 0.62 for major adverse events, and 0.62 for discharge destination other than home, all of which outperformed the MF-5.

DISCUSSION

The MF-6 was correlated with a 30-day postoperative incidence of infectious complications, readmission, and discharge destination. MF-6 scores can be used to risk-stratify patient populations as shifts to value-based care continue to develop.

Contralateral Total Hip Arthroplasty Staged Within Six Weeks Increases the Risk of Adverse Events Compared to Unilateral Surgery

BACKGROUND

The ideal timing for bilateral total hip arthroplasty (THA) remains controversial. This study compared 90-day outcomes after simultaneous bilateral THA and contralateral surgery in staged bilateral THA to a matched cohort of unilateral procedures.

METHODS

Patients undergoing primary, elective THA during 2015 to 2020 were reviewed in a national database. Of the 273,281 patients identified, 39,905 (14.6%) were bilateral. Patients were divided into cohorts of unilateral THA, simultaneous bilateral THA, and staged bilateral THA at 1 to 14 days, 15 to 42 days, 43 to 90 days, and 91 to 365 days. Bilateral THA cohorts were matched with unilateral THA patients based on demographics and comorbidities. Ninety-day outcomes after the second THA were compared between matched groups.

RESULTS

Simultaneous bilateral THA resulted in higher rates of transfusion (odds ratio [OR] 4.43, 95% confidence interval 2.31-2.63, P < .001), readmission (OR 2.60, 2.01-3.39, P < .001), and any complication (OR 1.86, 1.55-2.24, P < .001) compared to unilateral THA. Contralateral THA staged at 1 to 14 days increased the risk of readmission (OR 1.83, 1.49-2.24, P < .001) and any complication (OR 1.45, 1.26-1.66, P < .001) relative to unilateral THA. Contralateral THA staged at 15 to 42 days increased the risk of periprosthetic joint infection (OR 3.15, 1.98-5.19, P < .001), readmission (OR 1.92, 1.55-2.39, P < .001), and any complication (OR 1.70, 1.46-1.97, P < .001). Contralateral THA staged beyond 42 days resulted in similar or decreased rates of adverse events relative to unilateral THA.

CONCLUSIONS

Bilateral THA should be staged a minimum of 6 weeks apart in appropriately selected patients to avoid an increased risk of adverse events after the second THA compared to unilateral THA.

Total Hip Arthroplasty Imageless Navigation Does Not Reduce 90-Day Adverse Events or Five-Year Revisions in a Large National Cohort

BACKGROUND

Computer navigation is an increasingly utilized technology that is considered with total hip arthroplasty (THA). However, the evidence to support this practice is mixed. The current study leveraged a large national administrative database to compare 90-day adverse events as well as 5-year all-cause revision and dislocation rates following THA performed with and without imageless navigation.

METHODS

From 2010 to 2020, a large national database was queried for THA cases performed for osteoarthritis. Cases with or without imageless navigation were matched at 1:4 based on age, sex, and Elixhauser Comorbidity Index (ECI) score. Ninety-day adverse events were assessed and compared with multivariate analyses. Five-year incidence of revision and dislocation were also assessed between cohorts.

RESULTS

Use of THA imageless navigation increased from 2010 (2.5% of cases) to 2020 (5.5% of cases; P < .001). After matching, 11,990 THA patients with navigation and 47,948 without navigation were identified. Overall, 90-day adverse events were observed in 7.0% of the population. Multivariate analysis controlling for age, sex, and ECI demonstrated a difference in only one 90-day adverse event; wound dehiscence, which had higher odds in the navigation group (odds ratio, 1.60, P < .001). At 5 years, revisions for the navigated group were higher (4.4 versus 3.6%: P = .006), while dislocations were not significantly different.

CONCLUSION

THA imageless navigation was not found to be associated with improved 90-day postoperative adverse events or differences in the 5-year rates of revision or dislocation. The current data were unable to identify clear advantages of this evolving technology for primary THA.

Complications after high tibial osteotomy and distal femoral osteotomy are associated with increasing medical comorbidities and tobacco use

PURPOSE

The purpose of this study was to assess complications, reoperations, and their risk factors at 90 days and 2 years after high tibial osteotomy (HTO) and distal femoral osteotomy (DFO) in a national cohort.

METHODS

The PearlDiver Mariner Dataset was queried using International Classification of Diseases (ICD) and Current Procedural Terminology (CPT) codes for HTO and DFO, complications, and subsequent surgery. Minimum follow-up was 2 years and complications were assessed at 90 days and 2 years. Hospital readmission in the first 90 days was also assessed. Univariate and multiple logistic regression were utilized to identify risk factors for complications and re-operation.

RESULTS

The 90-day and 2-year complication rates after HTO (n = 1780) were 11.6% and 31.7%, compared to 21.5% (p < 0.0001) and 41.5% (p = 0.0001) after DFO (n = 446). Infection was the most frequent early (90-day) complication for both HTO and DFO cohorts, while hardware problems were most common at 2 years. Increasing Elixhauser Comorbidity Index (ECI) was associated with increased odds of infection, readmission, and hardware-associated complications in both cohorts. Gender and tobacco use were also associated with various complications after HTO. At 2 years, 23.7% of HTO patients and 26.2% of DFO patients had undergone subsequent surgery. Hardware removal occurred in 16.4% of HTO and 18.4% of DFO patients (n.s.), while 4.5% of HTO and 5.2% of DFO patients underwent total knee arthroplasty (TKA) within 2 years (n.s.).

CONCLUSION

HTO and DFO have substantial complication rates in the short and mid term, with a higher rate of overall complications observed after DFO as compared to the HTO cohort. After both procedures, roughly one quarter of patients will undergo subsequent surgery within 2 years. Patients with tobacco use and numerous medical co-morbidities may not be optimal candidates due to increased complication rates. Elixhauser Comorbidity Index (ECI) may be an useful tool for risk assessment prior to surgery.

LEVEL OF EVIDENCE

Retrospective cohort study, III.

Risk factors for venous thromboembolism following fractures isolated to the foot and ankle fracture

OBJECTIVE

Venous thromboembolism (VTE) is an uncommon, but potentially morbid, complication following foot and ankle fractures. Current standard is to not administer thromboprophylaxis to patients with such injuries. Nonetheless, patient and fracture factors might affect this risk/benefit consideration. The goal of this study was to determine what patients are most at risk.

METHODS

The M53Ortho Pearldiver database was used to identify patients with fractures isolated to the foot and ankle that were treated non-operatively or operatively. Patients with pilon, other appendicular fractures remote from the foot and ankle, and other traumatic injuries were excluded. The 90-day occurrence of VTE was identified based on codes for deep vein thrombosis or pulmonary embolism. Characteristics of those patients who did and did not have VTEs were compared using chi-square analyses. Multivariate logistical regression was then performed to determined factors independently associated with VTE. Finally, timing of VTE relative to fracture was analyzed.

RESULTS

A total of 298,886 patients with isolated foot or ankle fractures were identified, of which 1,661 (0.56%) had VTE in the 90 days following fracture. In terms of timing, 27.3% occurred in the first week, and 49.8% occurred in the first three weeks. Independent risk factors for VTE included (in decreasing order):prior VTE (odd ratio [OR] = 25.44), factor V Leiden (OR = 24.34), active cancer (OR = 1.84), specific fracture relative to metatarsal fracture (multiple fractures [OR: 1.51], ankle fracture [OR = 1.51], and calcaneus fracture [OR = 1.24]), surgical treatment (OR = 1.41), male sex (OR = 1.19), greater Elixhauser index (OR = 1.05), and increasing age (OR:1.05 per decade) (p<0.05 for each).

CONCLUSIONS

The present study found that, although only 0.56% of isolated foot and ankle fractures had a VTE within ninety days. Defined risk factors, such as Factor V Leiden, prior VTE, surgical treatment, active cancer, specific fracture patterns, and surgical treatment significantly affected the odds of their occurrence.

Underweight Body Mass Index Is Associated With Increased In-Hospital Complications and Length of Stay After Revision Total Joint Arthroplasty

INTRODUCTION

The purpose of this study was to assess the impact of underweight status on in-hospital postoperative outcomes and complications after revision total joint arthroplasty (rTJA) of the hip and knee.

METHODS

Data from the National Inpatient Sample were used to identify all patients undergoing rTJA in the United States between 2006 and 2015. Patients were divided into two groups based on a concomitant diagnosis of underweight body mass index and a control normal weight group. Propensity score analysis was performed to determine whether underweight body mass index was a risk factor for in-hospital postoperative complications and resource utilization.

RESULTS

A total of 865,993 rTJAs were analyzed. Within the study cohort, 2,272 patients were classified as underweight, whereas 863,721 were classified as a normal weight control group. Underweight patients had significantly higher rates of several comorbidities compared with the control cohort. Underweight patients had significantly higher rates of any complication (49.98% versus 33.68%, P = 0.0004) than normal weight patients. Underweight patients also had significantly greater length of stay compared with normal weight patients (6.50 versus 4.87 days, P < 0.0001).

CONCLUSION

Underweight patients have notably higher rates of any complication and longer length of stay after rTJA than those who are not underweight. These results have important implications in preoperative patient discussions and perioperative management. Standardized preoperative protocols should be developed and instituted to improve outcomes in this patient cohort.

The Impact of Morbid Obesity on In-hospital Outcomes after Revision Total Hip Arthroplasty: An Analysis of the National Inpatient Sample

Introduction:

There remain limited data on the effect of obesity on in-hospital outcomes after revision total hip arthroplasty (rTHA).

Methods:

Discharge data from the National Inpatient Sample were used to identify patients undergoing rTHA from 2006 to 2015. Propensity score analysis was done to analyze the effects of obesity and morbid obesity on in-hospital economic and complication outcomes after rTHA.

Results:

The estimated 460,297 rTHAs were done during the study period. Obese patients were more likely to suffer from any complication than not obese patients (41.44% versus 39.41%, P = 0.0085), and morbidly obese patients were more likely to suffer from any complication than obese patients (47.22% versus 41.44%, P < 0.0001). Obesity was associated with increased risk of postoperative anemia compared with not obese patients, while morbid obesity was associated with increased risk of postoperative anemia, hematoma/seroma, wound dehiscence, and postoperative infection (P < 0.05). Morbidly obese patients also had a significantly greater average length of stay (6.40 days) than obese (5.23 days) and not obese (5.37 days) patients (P < 0.0001).

Discussion:

Although both obesity and morbid obesity are associated with higher risk of in-hospital postoperative complications after rTHA, morbid obesity is a larger risk factor and is associated with a longer length of stay.

Hospital Burdens of Patients With Cerebral Palsy Undergoing Posterior Spinal Fusion for Scoliosis

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

Many patients undergoing posterior spinal fusion (PSF) for scoliosis have concurrent cerebral palsy (CP), which is associated with many medical comorbidities and inherent operative risk. We aimed to quantify the contribution of CP to increased cost, length of stay (LOS), and complication rates in patients with scoliosis undergoing PSF.

METHODS

Using the National Inpatient Sample database, we collected data regarding patient demographics, hospital characteristics, comorbidities, in-hospital complications, and mortality. Primary outcomes included complications, hospital LOS, and total hospital costs. Multivariate regression models assessed the contribution of CP to in-hospital complications, discharge status, and mortality. Linear regression identified the contribution of a diagnosis of CP on hospital LOS and inflation-adjusted cost.

RESULTS

Cerebral palsy was an independent predictor of several complications. The most striking differences were seen for mortality (odds ratio [OR]: 3.40, P < .001), a postoperative requirement for total parenteral nutrition (OR: 3.16, P < .001), urinary tract infection (OR: 2.75, P < .001), surgical site infection (OR: 2.67, P < .001), and pneumonia (2.21, P < .001). Patients with CP ultimately cost an additional $13 482 (P < .001) with a 2.07-day greater LOS (P < .001) than patients without CP.

CONCLUSION

Most complications were seen in higher rates in the CP cohort, with higher cost and LOS in patients with CP versus those with idiopathic scoliosis (IS). Our findings represent important areas of emphasis during preoperative consultations with patients with CP and their families. Extra care in patient selection and multifaceted treatment protocols should continue to be implemented with further investigation on how to mitigate common complications.

Predictivity of the comorbidity indices for geriatric syndromes

BACKGROUND

The aging population and increasing chronic diseases make a tremendous burden on the health care system. The study evaluated the relationship between comorbidity indices and common geriatric syndromes.

METHODS

A total of 366 patients who were hospitalized in a university geriatric inpatient service were included in the study. Sociodemographic characteristics, laboratory findings, and comprehensive geriatric assessment(CGA) parameters were recorded. Malnutrition, urinary incontinence, frailty, polypharmacy, falls, orthostatic hypotension, depression, and cognitive performance were evaluated. Comorbidities were ranked using the Charlson Comorbidity Index(CCI), Elixhauser Comorbidity Index(ECM), Geriatric Index of Comorbidity(GIC), and Medicine Comorbidity Index(MCI). Because, the CCI is a valid and reliable tool used in different clinical settings and diseases, patients with CCI score higher than four was accepted as multimorbid. Additionally, the relationship between geriatric syndromes and comorbidity indices was assessed with regression analysis.

RESULTS

Patients' mean age was 76.2 ± 7.25 years(67.8% female). The age and sex of multimorbid patients according to the CCI were not different compared to others. The multimorbid group had a higher rate of dementia and polypharmacy among geriatric syndromes. All four indices were associated with frailty and polypharmacy(p < 0.05). CCI and ECM scores were related to dementia, polypharmacy, and frailty. Moreover, CCI was also associated with separately slow walking speed and low muscle strength. On the other hand, unlike CCI, ECM was associated with malnutrition.

CONCLUSIONS

In the study comparing the four comorbidity indices, it is revealed that none of the indices is sufficient to use alone in geriatric practice. New indices should be developed considering the complexity of the geriatric cases and the limitations of the existing indices.

Effects of Comorbidities on Pain and Function After Total Hip Arthroplasty

Background

The growing number of patients undergoing total hip arthroplasty (THA) and postoperative outcomes receive increasing attention from doctors and patients. This study aimed to elucidate the effects of comorbidities on postoperative function, pain, complications, readmission rate, and mortality.

Methods

We included consecutive patients who underwent primary unilateral THA between 2017 and 2019. The Charlson comorbidity index (CCI) and the WOMAC and SF-36 (physical function, body pain) scales were assessed preoperatively and at 3, 6, 12, and 24 months postoperatively. The complications, 30-day readmission, and mortality rates assessed the impact of comorbidities and their changes over time on the WOMAC and SF-36 scores during follow-up. We used mixed model linear regression to examine the association of worsening comorbidity post-THA with change in WOMAC and SF-36 scores in the subsequent follow-up periods, controlling for age, length of follow-up, and repeated observations.

Results

This study included 468 patients, divided into four groups based on comorbidity burden (CCI-0, 1, 2, and ≥3). The physiological function recovery and pain scores in the CCI ≥ 3 group were inferior to the other groups and took longer than the other groups (6 vs. 3 months) to reach their best level. The four groups preoperative waiting times were 2.41 ± 0.74, 2.97 ± 0.65, 3.80 ± 0.53, and 5.01 ± 0.71 days, respectively. The complications, 30-day readmission, and 1-year mortality rates for the overall and the CCI ≥ 3 group were 1.92% and 4.69%, 0.85% and 2.01%, and 0.43% and 1.34%, respectively, with no mortality in the other groups.

Conclusion

Patients with higher CCI were more susceptible to physical function and pain outcome deterioration, experienced longer waiting time before surgery, took longer to recover, and had higher rates of complications, 30-day readmission, and mortality after THA. Older age in the group led to a greater impact.