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

Risk Factors for Readmission Following Surgical Decompression for Spinal Epidural Abscesses: An Analysis of 4595 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The study aimed to (1) compare baseline demographics of patients undergoing surgery for SEA who were/were not readmitted; (2) identify risk factors for 90-day readmissions; and (3) quantify 90-day episode-of-care health care costs.

BACKGROUND

Spinal epidural abscess (SEA), while rare, occurring ~2.5-5.1/10,000 admissions, may lead to permanent neurologic deficits and mortality. Definitive treatment often involves surgical intervention via decompression.

METHODS

A search of the PearlDiver database from 2010 to 2021 for patients undergoing decompression for SEA identified 4595 patients. Cohorts were identified through the International Classification of Disease, Ninth Revision (ICD-9), ICD-10, and Current Procedural Terminology codes. Baseline demographics of patients who were/were not readmitted within 90 days following decompression were aggregated/compared, identifying factors associated with readmission. Using Bonferroni correction, a P -value<0.001 was considered statistically significant.

RESULTS

Readmission within 90 days of surgical decompression occurred in 36.1% (1659/4595) of patients. While age/gender were not associated with readmission rate, alcohol use disorder, arrhythmia, chronic kidney disease, ischemic heart disease, and obesity were associated with readmission. Readmission risk factors included fluid/electrolyte abnormalities, obesity, paralysis, tobacco use, and pathologic weight loss ( P <0.0001). Mean same-day total costs ($17,920 vs. $8204, P <0.001) and mean 90-day costs ($46,050 vs. $15,200, P <0.001) were significantly higher in the readmission group.

CONCLUSION

A substantial proportion of patients (36.1%) are readmitted within 90 days following surgical decompression for SEA. The top 5 risk factors in descending order are fluid/electrolyte abnormalities, pathologic weight loss, tobacco use, pre-existing paralysis, and obesity. This study highlights areas for perioperative medical optimization that may reduce health care utilization.

How-To Create an Orthopaedic Systematic Review: A Step-by-step Guide Part II: Study Execution

Systematic reviews are the apex of the evidence-based pyramid, representing the strongest form of evidence synthesizing results from multiple primary studies. In particular, a quantitative systematic review, or meta-analysis, pools results from multiple studies to help answer a respective research question. The aim of this review is to serve as a guide on how to: (1) design, (2) execute, and (3) publish an orthopaedic arthroplasty systematic review. In Part II, we focus on methods to assess data quality through the Cochrane Risk of Bias, Methodological Index for Nonrandomized Studies criteria, or Newcastle-Ottawa scale; enumerate various methods for appropriate data interpretation and analysis; and summarize how to convert respective findings to a publishable manuscript (providing a previously published example). Use of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines is recommended and standard in all scientific literature, including that of orthopedic surgery. Pooled analyses with forest plots and associated odds ratios and 95% confidence intervals are common ways to present data. When converting to a manuscript, it is important to consider and discuss the inherent limitations of systematic reviews, including their inclusion and/or exclusion criteria and overall quality, which can be limited based on the quality of individual studies (eg, publication bias, heterogeneity, search/selection bias). We hope our papers will serve as starting points for those interested in performing an orthopaedic arthroplasty systematic review.

Risk Factors for Undergoing Surgical Intervention for Vertebral Compression Fractures: An Analysis of 703,499 Patients

BACKGROUND

Vertebral compression fractures (VCFs) are typically treated nonoperatively but can be treated with either kyphoplasty or vertebroplasty when indicated. The decision to treat patients with/without surgical intervention is dependent on the severity of deformity and patient risk profile. The aims of this study were to: 1) compare baseline patient demographics, 2) identify risk factors of patients undergoing operative vs. nonoperative management, and 3) identify patient-specific risk factors associated with postoperative readmissions.

METHODS

This retrospective database study used patient information from January 1st, 2010, to October 31st, 2021. Cohorts were identified by patients diagnosed with VCFs through International Classification of Disease, Ninth Revision (ICD-9), ICD-10 codes, identifying those undergoing kyphoplasty/vertebroplasty via Current Procedural Terminology codes. The 2 research domains utilized in this investigation were baseline demographic profiles of patients who underwent kyphoplasty or vertebroplasty for treatment of VCFs, and those who underwent nonoperative management served as the control cohort.

RESULTS

Of the 703,499 patients diagnosed with VCFs, 76,126 patients (10.8%) underwent kyphoplasty or vertebroplasty within 90 days of diagnosis of a VCF. Univariate analysis demonstrated female sex was associated with increased risk of undergoing surgical management for VCF (P < 0.0001). Several comorbidities were significantly associated with increased rates of readmission including hypertension, tobacco use, coronary artery disease, and chronic obstructive pulmonary disease (P < 0.0001 for all).

CONCLUSIONS

This study highlights specific comorbidities that are significantly associated with higher rates of kyphoplasty or vertebroplasty for the treatment of thoracolumbar wedge compression fractures and increased risk for 90-day postoperative hospital readmission.

How-To Create an Orthopaedic Systematic Review: A Step-by-Step Guide Part I: Study Design

Systematic reviews are conducted through a consistent and reproducible method to search, appraise, and summarize information. Within the evidence-based pyramid, systematic reviews can be at the apex when incorporating high-quality studies, presenting the strongest form of evidence given their synthesis of results from multiple primary studies to level IV evidence, depending on the studies they incorporate. When combined and supplemented with a meta-analysis using statistical methods to pool the results of 3 or more studies, systematic reviews are powerful tools to help answer research questions. The aim of this review is to serve as a guide on how to: (1) design; (2) execute; and (3) publish an orthopaedic arthroplasty systematic review and meta-analysis. In Part I, we discuss how to develop an appropriate research question as well as source and screen databases. To date, commonly used databases to source studies include PubMed/MEDLINE, Embase, Cochrane Library, Scopus, and Web of Science. Although not all-encompassing, this paper serves as a starting point for those interested in performing and/or critically reviewing lower extremity arthroplasty systematic reviews and meta-analyses.

Projected volume of primary total joint arthroplasty in the USA from 2019 to 2060

INTRODUCTION

The global incidence of total joint arthroplasty (TJA) has consistently risen over time, and while various forecasts differ in magnitude, future projections suggest a continued increase in these procedures. Differences in future United States projections may arise from the modeling method selected, the nature of the national arthroplasty registry employed, or the representativeness of the specific hospital discharge records utilized. In addition, many models have not accounted for ambulatory surgery as well as all payer types. Therefore, to attempt to make a more accurate model, we utilized a national representative sample that included outpatient arthroplasties and all insurance types to predict the volumes of primary TJA in the USA from 2019 to 2060.

METHODS

A national, all-payer database was queried. All patients who underwent primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) from January 1, 2010, to December 31, 2019, were identified using international classification of disease Ninth Revision (9) and Tenth Revision (10) codes and current procedure terminology codes. Absolute frequencies and incidence rates were calculated per 100,000 for both THA and TKA procedures, with 95% confidence intervals. Mean growth in absolute frequency and incidence rates were calculated for each procedure from 2010 to 2014, and 2010 to 2019, with 95% confidence intervals (CI).

RESULTS

The overall increase in THA and TKA procedures are expected to grow + 10 and + 36%, respectively, using linear regressions and + 9 and + 37%, respectively. The most positive mean growth in procedure frequency occurred from 2010 to 2014 for THA (+ 24, 95% Confidence Interval (CI): + 21, + 27) and 2010-2019 for TKA (+ 11%, 95% CI: + 9, + 14). There positive trend patterns in incidence rate growth for both procedures, with similar 2010-2019 incidence rates + 6%) for THA (+ 3%, 95% CI: + 0, + 6%) and TKA (+ 3%, 95% CI: + 1%, + 6%).

CONCLUSION

Utilizing a nationally representative database, we demonstrated that TJA procedures would continue with an increased growth pattern to 2060, though slightly decreased from the surge from 2014 to 2019. While this finding applies to the representativeness of the population at hand, the inclusion of outpatient arthroplasty and all payer types validates an approach that has not been undertaken in previous projection studies.

Cryoneurolysis Associated With Improved Pain, Function, and Sleep in Patients Following total Knee Arthroplasty: Use of a New Real-World Registry

BACKGROUND

Total knee arthroplasty (TKA) is performed on approximately 790,000 patients annually in the United States and is projected to increase to 1.5 million by 2050. This study aimed at assessing the use of preoperative cryoneurolysis on patients undergoing TKA by analyzing: (1) pain severity; (2) opioid use; (3) functional status; and (4) sleep disturbance (SD) over 6 months following discharge.

METHODS

Patients enrolled in the Innovations in Genicular Outcomes Registry between September 2021 and February 2024 were followed for 6 months. Our analyses included patients undergoing unilateral primary TKA with no preoperative opioid prescription, who either received cryoneurolysis, or did not. Baseline patient demographics were collected before TKA and tabulated. Pain management was assessed via the Brief Pain Inventory-Short Form instrument for pain severity. SD was measured using the patient-reported outcomes measurement information system questionnaire. Each outcome measure was assessed prior to TKA, weekly, and at monthly follow-up. Data were analyzed by a generalized linear mixed-effect regression model to compare cryoneurolysis versus control patients, with a P < .05 as significant.

RESULTS

There were 80 patients who were treated with preoperative cryoneurolysis, while 60 control patients did not have treatment. Patients receiving cryoneurolysis experienced significantly lower pain severity and SD over the 6-month follow-up than control patients (P = .046). Cryoneurolysis was also associated with a trend toward greater functional improvement that did not reach statistical significance (P = .061). Further, patients who underwent cryoneurolysis were 72% less likely than control group patients to take opioids over 6 months following discharge (P < .001).

CONCLUSIONS

Preoperative cryoneurolysis therapy in opioid-naive patients undergoing TKA is associated with improved pain, decreased opioid use, and improved SD for 6 months postoperatively. Cryoneurolysis, a nonopioid pain relief modality administered preoperatively, demonstrated substantial benefits in patients who underwent TKA.

Improved Pain and Function With Triamcinolone Acetonide Extended-Release and Cryoneurolysis for Knee Osteoarthritis: Use of a New Real-World Registry

BACKGROUND

Knee osteoarthritis (OA) affects 19% of American adults aged more than 45 years and costs $27+ billion annually. A wide range of nonoperative treatment options are available. This study compared 6 treatments: cryoneurolysis with deep genicular nerve block (Cryo-Deep/Both), cryoneurolysis with superficial nerve block (Cryo-Superficial), intra-articular hyaluronic acid (IA-HA) injections, nonsteroidal anti-inflammatory drug injections (IA-NSAIDs), IA-corticosteroids (IA-CS) injections, or IA-triamcinolone extended release (IA-TA-ER) injections over 4 months for: (1) pain severity and analgesic use; and (2) physical function (from Knee Injury and Osteoarthritis Outcome Score for Joint Replacement).

METHODS

Patients who had unilateral knee OA and received nonoperative intervention were enrolled in the Innovations in Genicular Outcomes Research registry, a novel, multicenter real-world registry, between September 2021 and February 2024. A total of 480 patients were enrolled. Both pain and functional outcomes were assessed at baseline, weekly, and monthly, which were analyzed by overall trend, magnitude changes pretreatment to post-treatment, and distribution-based minimally clinically important difference (MCID) score. Multivariate linear regressions with adjustments for 7 confounding factors were used to compare follow-up outcomes among 6 treatment groups.

RESULTS

Use of IA-TA-ER injections was associated with the lowest pain, greatest pain reduction, and highest prevalence of patients achieving MCID relative to other treatments (P < .001). Deep/Both-Cryo and IA-CS were associated with a higher prevalence of achieving MCID than IA-HA, IA-NSAIDs, and Cryo-Superficial (P ≤ .001). Use of IA-TA-ER was also associated with the greatest functional score, improvement from baseline, and highest prevalence of patients achieving MCID than other treatments (P ≤ .003).

CONCLUSIONS

The IA-TA-ER appears to outperform other treatments in terms of pain relief and functional improvement for up to 4 months following treatment. In addition, outcomes in the novel cryoneurolysis and conventional IA-CS were similar to one another and better than those in IA-HA and IA-NSAIDs.

How-To Create an Orthopaedic Systematic Review: A Step-by-Step Guide. Part III: Executing a Meta-Analysis

At the top of the evidence-based pyramid, systematic reviews stand out as the most powerful, synthesizing findings from numerous primary studies. Specifically, a quantitative systematic review, known as a meta-analysis, combines results from various studies to address a specific research question. This review serves as a guide on how to: (1) design; (2) perform; and (3) publish an orthopedic arthroplasty systematic review. In Part III, we focus on how to design and perform a meta-analysis. We delineate the advantages and disadvantages of meta-analyses compared to systematic reviews, acknowledging their potential challenges due to time constraints and the complexities posed by study heterogeneity and data availability. Despite these obstacles, a well-executed meta-analysis contributes precision and heightened statistical power, standing at the apex of the evidence-based pyramid. The design of a meta-analysis closely mirrors that of a systematic review, but necessitates the inclusion of effect sizes, variability measures, sample sizes, outcome measures, and overall study characteristics. Effective data presentation involves the use of forest plots, along with analyses for heterogeneities and subgroups. Widely-used software tools are common in this domain, and there is a growing trend toward incorporating artificial intelligence software. Ultimately, the intention is for these papers to act as foundational resources for individuals interested in conducting systematic reviews and meta-analyses in the context of orthopaedic arthroplasty, where applicable.

Miscoding in the Nationwide Inpatient Sample Database Raises Questions About Validity for Arthroplasty Research

BACKGROUND

The use of administrative databases in arthroplasty research has increased over the past decade. The Nationwide Inpatient Sample (NIS) is one of the first and most frequently used. Despite many published articles using this dataset, there exists no standardization resource accounting for the potential of biased results. The purpose of our study was to assess the amount of discordant data between clinically relevant variables and propose a standard for using this database in primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

An initial set of patients undergoing total joint arthroplasty were identified from the NIS between 2016 and 2019 using the International Classification of Diseases, 10th Revision, Procedure Coding System. All records with THA and TKA in any of the procedure variables (PR1-PR20) were included. A total of 63 relevant and consistent variables were selected for individual comparison including diagnosis-related group (1), elective (1), procedure codes (20), day of main procedure (1), and diagnosis codes (40). Descriptive statistics were used. A total of 3,562,819 patients were included in the initial set.

RESULTS

Using diagnosis-related groups, 5.3% were revision surgeries, 4.7% were not elective, 2.3% did not have THA or TKA as their primary procedure for hospitalization, and 2.9% of THA and 9.7% of TKA were bilateral. A total of 6.2% of the surgeries were done day(s) before or after admission, and 10.8% of THA and 6.3% of TKA were missing an orthopedic diagnosis for admission. Many had multiple orthopedic diagnoses for admission, 3.2% of THA and 0.7% of TKA. Overall miscoding was 23.3%.

CONCLUSIONS

Using the NIS without standardized data processing to study elective, unilateral, primary THA and TKA introduces major bias. A logical and stepwise approach to curate the data before analysis is proposed to improve research quality when using this database in hip and knee arthroplasty studies.