5-year Revision Research Articles

Hospital Network Centralization of Primary Total Joint Arthroplasty Is Associated With Reduced Early Complication Rates But Not Reduced Readmission or Reoperation Rates: A Retrospective Database Study

Background: Hospital networks centralize primary total joint arthroplasty (TJA) within their existing systems to develop specialized service lines with higher surgical volumes to reduce adverse events. It is not known what role hospital network centralization has had on primary TJA outcomes. Purpose: We sought to determine whether the degree of hospital network centralization for primary TJA is associated with (1) 90-day postoperative complication rates, (2) 90-day hospital readmission rates, or (3) 1-year revision rates. Methods: We conducted a retrospective database study of Medicare Part A beneficiaries who underwent inpatient primary TJA for osteoarthritis in 2016 and 2017 ( n = 523,142 patients); individual hospital-level characteristics and hospital networks were also identified ( n = 360 unique networks, n = 3339 hospitals). Patients having surgery at a hospital that was not a member of a health care network were excluded ( n = 163,998 patients) because we wanted to examine only the role of network structures on outcomes; this resulted in a cohort of 359,144 patients. Hospital network centralization, which was defined as the percentage of total network cases performed at the highest volume hospital and categorized into quartiles (eg, lowest 25% of networks by concentration, 26%–50% of networks by concentration, etc). Primary outcomes included postoperative 90-day complications, 90-day readmissions, and 1-year revisions. Multivariable logistic and linear regressions evaluated associations of hospital network centralization with outcomes and controlled for relevant patient-level and hospital-level covariates, including hospital network volumes. Results: Odds of 90-day complications were lower in the most centralized hospital networks than in least centralized networks (odds ratio [OR] = 0.85; 95% confidence interval [CI]: 0.75, 0.95). Degree of centralization was not associated with readmissions or 1-year revision rates. Non-modifiable patient and individual hospital characteristics appeared to have a greater association with complications, readmissions, and early revision rates than hospital network centralization or volume. Conclusion: This retrospective database study found that increased centralization of primary TJA within a hospital network was associated with lower 90-day complication rates but not with 90-day readmission or 1-year revision rates. This suggests that structural changes within hospital networks may be beneficial to reduce early complications in this patient population. In addition, our findings suggest that risk adjustment in assessing non-modifiable patient and hospital risk factors may be important when assessing TJA outcomes.

Declining Trends in Septic Revision Following Total Knee Arthroplasty From 2010 to 2019: A National Cohort Analysis

Periprosthetic joint infections (PJI) following total knee arthroplasty (TKA) are associated with high patient morbidity, mortality, and healthcare costs. Methods to reduce the burden of PJI have been shown to be efficacious on a small scale. On a national scale, it is unknown whether these methods have reduced PJI rates. A retrospective trend analysis was conducted using a national database. The incidence of 2-year septic revision was observed for the entire cohort and patients who had high-risk co-morbidities from 2010 to 2019. A multivariable logistic regression was performed to compare the odds ratios of 2-year septic revision rates from 2011 to 2019 to the reference year of 2010. Linear regression was used to compare the change throughout this period in the overall and high-risk sub-analysis groups. Among the 860,185 patients, 5,589 underwent septic revision within 2 years. The 2-year septic revision rate decreased from 0.75% in 2010 to 0.69% in 2019 (compounded annual growth rate [CAGR] = -0.94%, P = 0.049). Multivariable logistic regressions demonstrated that the odds of septic revision in 2019 were significantly lower than those in 2010 (OR [odds ratio]: 0.83, 95% CI [confidence interval]: [0.70 to 0.96], P = 0.017). In high-risk patients, the septic revision rate decreased from 1.04 to 0.80% (CAGR = -2.80%, P = 0.004), specifically in those who had a history of psychoses, Medicaid insurance, anemia, heart failure, obesity, liver disease, tobacco use, and drug abuse (P < 0.05 for all). This study demonstrates a national reduction in the 2-year septic revision rate in all TKA patients, including patients considered at high risk for PJI. This suggests current preventative methods may be efficacious on a national scale in TKA. Further research is needed to identify more modalities to reduce the national incidence of this morbid and costly complication.

Preoperative Anxiety: An Important Risk Factor of Postoperative Adverse Events and Increased Reoperation Rates in Patients Undergoing Single-Level Anterior Cervical Diskectomy and Fusion

Introduction: With the rising prevalence of mental health disorders, it is important to consider their correlation with surgical outcomes. Anxiety has been associated with adverse events after many surgical procedures, but its relationship relative to anterior cervical diskectomy and fusion (ACDF) regarding medical complications has not previously been assessed in a large database study. Methods: The 2010-Q3 2022 PearlDiver Mariner161 database was used to identify patients undergoing single-level ACDF. Those with versus without preoperative anxiety were matched 1:1 based on age, sex, and Elixhauser Comorbidity Index. Rates of 90-day adverse events were compared by multivariate regression analyses, and 5-year cervical revision surgery rates were compared. Results: Of 287,278 ACDF patients, preoperative anxiety was identified for 36.73%. After matching, patients with anxiety had greater odds ratios of all assessed individual 90-day adverse outcomes, as well as any (OR: 3.09), severe (OR: 2.07), and minor (OR: 3.39) adverse events (P &lt; 0.0001 for all). Those with preoperative anxiety had slightly greater 5-year rates of subsequent cervical spine surgery than those without (P &lt; 0.0001, at 5 years 12.9% versus 11.7%). Discussion: ACDF patients with a history of anxiety had higher odds of many 90-day adverse outcomes and slightly higher 5-year revision surgery rates. These findings may inform patient counseling and risk management strategies.

Enhanced Risk of 90-Day Medical and 2-Year Implant Related Complications in Total Shoulder Arthroplasty Patients with Osteoporosis.

BackgroundAs the average age of patients undergoing shoulder arthroplasty (SA) increases, the frequency of SA patients with osteoporosis is expected to rise. While the effects of osteoporosis have been described in the broader orthopedic literature, it is presently unclear how osteoporosis affects SA postoperative medical and implant-related outcomes. MethodsA multicenter database TriNetX was queried for patients between 2011-2021 who underwent SA with and without osteoporosis. Patients with less than 2-years of follow-up and those with a prior shoulder hemiarthroplasty were excluded. Primary outcomes included 2-year periprosthetic joint infection (PJI), prosthesis dislocation, periprosthetic fracture, and revision surgery. Secondary outcomes included 90-day medical complications and readmissions. Osteoporotic and control patient cohorts were propensity matched in a 1:1 ratio. Results7,842 patients were included after matching in each cohort. Baseline demographic variables were similar between groups, except osteoporotic patients had a lower BMI (28.6 vs 31.0 kg/m2; p < 0.001). Osteoporotic patients undergoing SA were more likely to experience wound disruptions, stroke, pulmonary embolism, deep vein thrombosis, myocardial infarction, anemia, pneumonia, renal failure, transfusion, and readmission within 90 days after surgery. At 2 years postoperative, osteoporotic SA patients experienced an elevated risk of mechanical loosening, PJI, dislocation, periprosthetic fracture, and required revision surgery at a higher rate than control patients. ConclusionsOsteoporotic patients undergoing shoulder arthroplasty are at greater risk for medical complications within the 90-day peri-operative period as well as implant-related complications within 2 years of surgery. Patients and surgeons should be aware of the potential higher risk of complications in osteoporotic patients following SA, and further investigation into benefits of preoperative management and treatment of osteoporosis is necessary.

Revision rates of one new and two established hemiarthroplasty heads: a comparative cohort study from the Swedish Arthroplasty Register

Introduction: The anatomical Lubinus SPII-stem is commonly used in hemi-arthroplasty for femoral neck fractures (FNF), combined with either the bipolar Variocup, the Unipolar Head (UH) and a newly introduced unipolar Modular Trauma Head (MTH). Similar constructs like the MTH are reported to have risk of corrosion and wear. This is the first publication evaluating the MTH. Aim: To describe the revision rate of the SPII-stems/heads which were divided into 3 groups (Variocup, UH, MTH). The head types are compared by their rate of revision at 2 years, due to any cause and to dislocation. Revision and mortality rates up to 10 years are reported. Methods: This observational cohort study based on prospectively registered data from the Swedish Arthroplasty Register included 33,059 patients with hemiarthroplasty 2005–2021 due to FNF. SPII-stems combined with Variocup ( n = 7,281), UH ( n = 23,980), MTH ( n = 1,798) were included. The follow-up ended at 10 years for Variocup and UH, for MTH at 2 years. Kaplan-Meier survival analyses was used, with a 95% confidence interval (CI). Patients were censored at death or at the end of the study (31 December 2021). Results: The 2-year revision rate regardless of cause was similar between the groups: after Variocup 3.5% (CI, 3.1–4.0), UH 3.1% (CI, 2.9–3.4), MTH 3.5% (CI, 2.6–4.5). At 10 years, the Variocup and UH had similar revision rates; 4.6% (CI, 4.0–5.2) and 5.0% (CI, 4.4–5.6). For revision due to dislocation at 2 years Variocup 2.3% (CI, 1.9–2.7) had an inferior outcome compared to UH 1.5% (CI, 1.3–1.7). The MTH had an intermediate outcome, 1.7% (CI, 1.0–2.3). Variocup had a higher dislocation related revision rate, until the 10th year. The 2-year-mortality was 36% (CI, 35–37) after Variocup, 43% (CI, 42–43) after UH and 44% (CI, 41–47) after MTH. Conclusions: The hemi-heads have comparable revision rates within 2 and 10 years. The new MTH performs similar to the standard UH. The bipolar Variocup is associated with more revisions due to dislocation.

Routine Prescription of Proton Pump Inhibitors in the Perioperative Period is Associated With Decreased Rates of 2-Year Revision Surgery After Total Hip and Knee Arthroplasty

BackgroundProton pump inhibitors (PPIs) are often prescribed in conjunction with nonsteroidal anti-inflammatory drugs after total hip arthroplasty (THA) and total knee arthroplasty (TKA) due to their gastroprotective effects. In animal studies, it has been suggested that PPIs have immunosuppressive effects and impair fracture healing; however, the association between PPI use and adverse events following THA and TKA has not been well-studied. MethodsAn administrative claims database was queried for patients who underwent elective THA from 2010 to 2019. The experimental group consisted of patients who did not have a prior history of gastrointestinal bleeding or gastroesophageal reflux disease and who received a PPI prescription in the perioperative period. A 1:1 propensity score matching was used to create control cohorts of patients who did not have any PPI prescription filled, also matching for age, sex, and the Charlson Comorbidity Index. This same cohort selection and matching procedure was then repeated for patients undergoing elective TKA. In total, 11,450 patients were studied (3,103 TKA + PPI, 2,622 THA + PPI, 3,103 TKA controls, and 2,622 THA controls). The mean age was 64 years (range, 38 to 94), and 57% were women. Significance was considered at P < 0.05. ResultsPerioperative PPI prescription in TKA patients was associated with significantly lower rates of all-cause revision (3.0 versus 4.1%, P < 0.01) and periprosthetic joint infection (1.0 versus 1.8%, P < 0.01). In THA patients, PPI prescription was associated with a lower all-cause revision rate (2.8 versus 4.0%, P = 0.02). No significant differences were found between PPI and non-PPI groups for aseptic loosening, periprosthetic fracture, gastrointestinal bleeding, or surgical site infection in either cohort. ConclusionsPatients receiving routine PPI prescriptions in the perioperative period surrounding TKA and THA have a lower risk of all-cause revision surgery, and perioperative PPI use is associated with a decreased risk of PJI in patients undergoing TKA. As these results conflict with the few previous studies performed on this topic, additional controlled studies are warranted to fully elucidate the relationship between PPI use and adverse events after THA and TKA.

NO DIFFERENCE IN SHORT-TERM REVISION RATE AND EARLY MORTALITY IN UNCEMENTED VERSUS CEMENTED TOTAL HIP ARTHROPLASTY: A REGRESSION DISCONTINUITY ANALYSIS IN THE DUTCH ARTHROPLASTY REGISTER DATA

Controversy persists over whether cemented or uncemented fixation is more effective in reducing revision and mortality risks following primary total hip arthroplasty (THA). Despite a shift towards uncemented THA in Europe, Australia, and the US, no consensus exists on superior outcomes. This ambiguity in evidence from randomized controlled trials (RCTs) and observational studies necessitates advanced research methodologies to derive more definitive conclusions.This study investigates the causal impact of THA fixation type on 2-year and 5-year revision rates, along with 90-day mortality, utilizing a regression discontinuity (RD) design in scenarios where fixation choice is guided by patient age.Employing data from the Dutch Arthroplasty Register, we conducted a cohort study on primary THAs for osteoarthritis from 2007 to 2019. A “fuzzy” RD design was executed to compute the Local Average Treatment Effect for subjects around the age-based selection threshold for fixation type. The main outcome of interest was the revision rate at 2 years post-operation.Analysis for the 2-year revision endpoint, covering any cause, included 2,344 females and 1,671 males across 5 hospitals each, with no significant variation in revision rates observed. For the 5-year mark, 1,058 females in 3 hospitals and 214 males in 1 hospital were examined, similarly showing no significant differences. Mortality within 90 days post-operation was also investigated in 5 female and 7 male cohorts, with 2,180 and 2,145 surgeries respectively, yielding no substantial disparities.In conclusion, the RD analysis revealed no notable differences in revision rates at 2 and 5 years or in early mortality based on the fixation method used in THA. These outcomes suggest that the age-based preference for THA fixation may not influence the revision or mortality risk, underscoring the value of RD design in deriving causal insights from observational data.

The Impact of Surgeon Volume on Unicompartmental Knee Arthroplasty Survivorship: A Michigan Arthroplasty Registry Collaborative Quality Initiative Database Analysis

BackgroundThe utilization of unicompartmental knee arthroplasty (UKA) has remained low when compared to total knee arthroplasty (TKA), possibly due to higher rates of revision and reoperation. This study aimed to quantify surgeon UKA case-volumes and measure the effect of surgeon volume on early revision. We hypothesized that surgeons who have high case volumes would have lower revision rates compared to medium- and low-volume surgeons. MethodsPrimary UKAs were performed between February 2012 and November 2021, and associated revisions were identified utilizing the Michigan Arthroplasty Registry Collaborative Quality Initiative. Surgeon information, including total cases and annual UKA volume, was collected. Case volume per year was stratified as High (≥ 35 cases per year), Medium (15 to 34 cases per year), and low (< 15 cases per year). ResultsThere were a total of 15,542 UKAs performed. Of these, 701 (4.5%) were revised, and 412 (58.8%) revisions occurred within 2 years. Of the 287 surgeons who performed an UKA in the registry, 237 (82.6%) were low-volume surgeons, 36 (12.5%) were medium-volume, and 14 (4.9%) were high-volume. High-volume surgeons were more likely to operate on older patients (P < 0.01), Medicare patients (P < 0.01), and patients who had American Society of Anesthesiologists scores of III and IV (P < 0.01). High-volume surgeons had significantly lower 5-year revision rates compared to medium and low-volume surgeons (high: 4.3% (95% confidence interval: 3.7 to 4.9), medium: 5.2% (4.4 to 6.1), low: 7.2% (6.4 to 8.0); P < 0.001). In comparison, the 5-year revision rate for TKA in Michigan was 3.0% (95% confidence interval: 2.9 to 3.1). ConclusionsWhen UKAs were performed by high-volume surgeons in the state of Michigan, there was better survivorship when compared to low-and medium-volume surgeons. High-volume surgeons were more likely to perform UKA on older patients, Medicare patients, and patients who had American Society of Anesthesiologists scores of III and IV. The revision rate for the high-volume surgeons still exceeded the 5-year revision rate for TKA in Michigan.

Best timing of bilateral total hip arthroplasty – an analysis of revision and mortality rates from the German Arthroplasty Registry (EPRD)

BackgroundThe burden of osteoarthritis (OA) in multiple joints is high and for patients with bilateral OA of the hip there is no clear recommendation about the indication for simultaneous (one-stage) bilateral total hip arthroplasty (THA) versus two-staged procedures. The purpose of this study was therefore to compare revision and mortality rates after different strategies of surgical timing in bilateral hip OA from the German Arthroplasty Registry (EPRD).MethodsSince 2012 22,500 patients with bilateral THA (including 767 patients with one-staged bilateral surgery and 11,796 patients with another separate procedures within one year after first THA) are documented in the registry. The patients who underwent simultaneous bilateral THA were matched with a cohort of 767 patients who underwent the second THA between 1 and 90 days postoperatively (short interval) and another cohort of 4,602 patients with THA between 91 and 365 days postoperatively (intermediate interval). Revision for all reasons and mortality rates were recorded. Cox regression was performed to evaluate the influence of different patient characteristics.ResultsThe cumulative 5-year revision rate for patients with simultaneous bilateral THA was 1.8% (95% CI 0.9–2.6), for patients with two-staged THA 2.3% (95% CI 1.0-3.6) in the short interval and 2.5% (95% CI 2.1–2.9) in the intermediate interval, respectively. In all three groups, patients who underwent THA in a high-volume center (≥ 500 THA per year) had a significant lower risk for revision (HR 0.687; 95% CI 0.501–0.942) compared to surgeries in a low-volume center (< 250 THA per year). There was no significant difference regarding cumulative mortality rates in the three cohorts. Higher age (HR 1.060; 95% CI 1.042–1.078) and severe comorbidities as reflected in the Elixhauser Score (HR 1.046; 95% CI 1.014–1.079) were associated with higher mortality rates after simultaneous THA.ConclusionSimultaneous bilateral THA seems to be a safe procedure for younger patients with limited comorbidities who have bilateral end-stage hip OA, especially if performed in high-volume centers.Level of evidenceIII.

Increased 1-Year Revision Rates Among Left-Sided Intertrochanteric Femur Fractures.

To compare 1-year revision rates among left-sided and right-sided intertrochanteric femur fractures. Retrospective. 120+ contributing centers to multicentered database. Patients who sustained intertrochanteric femur fracture (ITFF) and had a cephalomedullary nail (CMN) from 2015 to 2022 were identified. Patients were then stratified based on left-sided or right-sided fracture. Patients were excluded if younger than 18 years with <1-year follow-up. The intervention investigated was CMN on left or right side. One-year revision surgery, comparing CMN performed on left or right side for ITFFs. In total, 113,626 patients met inclusion criteria, with 55,295 in the right-sided cohort and 58,331 in the left-sided cohort. There was no difference between cohorts with respect to age, gender, diabetes, osteoporosis, chronic kidney disease, or congestive heart failure (P > 0.05 for all). Patients who sustained a left ITFF and treated with a CMN were more likely to have revision surgery at 1 year (Left: 1.24%, Right: 0.90%; OR: 1.24; 95% confidence interval [CI], 1.15-1.1.33) or develop a nonunion or malunion (Left: 1.30%, Right: 0.98%; OR: 1.31; 95% CI, 1.14-1.52). The most common revision surgery conducted for both cohorts was conversion total hip arthroplasty (Left: 70.4% and Right: 70.0%). Patients who sustained a left intertrochanteric femur fracture and were treated with a CMN were more likely to undergo revision at 1 year due to nonunion. There were no differences in demographics and comorbidities between cohorts. Though left-sided versus right-sided confounding variables may exist, the difference in nonunion rate may be explained by clockwise torque of the lag screw used in most implants. Increased awareness, implant design, and improved technique during fracture reduction and fixation may help lower this disproportionate nonunion rate and its associated morbidity and financial impact. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Total Knee Arthroplasty in Patients with Cerebral Palsy: A Large Database Analysis.

Cerebral palsy (CP) is a neurodevelopmental condition that can result in altered gait biomechanics, joint dysfunction, and imbalance. The complications associated with total knee arthroplasty (TKA) in patients with CP have not yet been well described. Therefore, our analysis sought to compare the 90-day and 2-year complications following TKA in patients with and without CP. The PearlDiver Mariner database was utilized to identify patients with CP undergoing primary TKA between 2010 and 2020. This cohort was matched 1:4 to a control cohort without neurodegenerative disorders based on age, sex, Elixhauser Comorbidity Index (ECI), tobacco use, obesity, and diabetes. A total of 3,257 patients (657 CP patients 2,600 controls) were included in our final analysis. A multivariable logistic regression analysis was utilized to determine the risk of CP on medical and surgical complications at 90 days and all-cause revision rates at 2 years. Patients with CP had an increased risk of acute kidney injury (odds ratio [OR]: 1.66; 95% confidence interval [CI]: 1.07-2.5; p = 0.019), pneumonia (OR: 5.63; 95% CI: 3.69-8.67; p < 0.001), urinary tract infection (OR: 5.01; 95% CI: 3.85-6.52; p < 0.001), and transfusion (OR: 2.21; 95% CI: 1.50-3.23; p < 0.001). CP patients additionally had a higher incidence of emergency department (ED) visits (OR: 5.24; 95% CI: 3.76-7.32; p < 0.001) and readmissions (OR: 5.24; 95% CI: 2.57-4.96; p < 0.001). There were no differences in rates of periprosthetic joint infection (PJI; OR: 1.23; 95% CI: 0.69-2.10; p = 0.463), surgical site infection (SSI; OR: 0.51; 95% CI: 0.12-1.46; p = 0.463), and reoperation (OR: 1.35; 95% CI: 0.71-2.43; p = 0.339) at 90 days postoperatively. The all-cause revision rates at 2 years were comparable (OR: 1.02; 95% CI: 0.67-1.51; p = 0.927). In this database review, we found that CP patients have a higher risk of medical complications in the acute postoperative period following TKA. The 90-day surgical complication and 2-year revision rates in CP patients were comparable to matched controls.

Social Determinants of Health Disparities Increase 5-Year Revision Rates but Not Postoperative Complications After Primary Hip Arthroscopy

To investigate the impact of social determinants of health (SDOH) disparities on 30-day emergency department (ED) visits, 90-day postoperative complications, and five-year secondary surgery rates after primary hip arthroscopy using a large national database. A national administrative claims database was used to identify patients who underwent primary hip arthroscopy with femoroplasty, acetabuloplasty, and/or labral repair between 2015 and 2022. Patients were queried for whether they experienced any SDOH disparities, including economic, educational, environmental, or social disparities; those experiencing SDOH within 1 year prior to primary hip arthroscopy were matched 1:1 by age, sex, Elixhauser Comorbidity Index score, diabetes, obesity, and tobacco use to patients not experiencing any lifetime SDOH disparities. Odds of 90-day complications and 30-day ED visits were compared using multivariable logistic regression. Rates of five-year revision hip arthroscopy and of any secondary surgery (revision hip arthroscopy or total hip arthroplasty) were compared by Kaplan-Meier analysis. A total of 3,383 primary hip arthroscopy patients who experienced SDOH disparities were matched 1:1 to a control cohort of 3,383 patients who had not experienced SDOH (age, 41.0 years, 79.6% female, for both cohorts). Odds of adverse events following arthroscopy were low and not different between cohorts (SDOH: 1.51%, vs. No SDOH: 1.57%; P=0.09). Additionally, there was no difference in odds of 30-day ED visits (SDOH: 5.65%, vs. No SDOH: 4.79%; P=0.10). The rate of five-year revision hip arthroscopy was significantly greater among patients experiencing SDOH disparities (5.4% vs. 4.1%; P=0.02); however, there was no difference in rates of any secondary surgery between cohorts (11.8% vs. 10.4%; P=0.10). Patients experiencing SDOH disparities had similar odds of postoperative complications and ED visits after primary hip arthroscopy but greater rates of five-year revision hip arthroscopy compared to a matched-control cohort of patients not experiencing SDOH disparities. 3; retrospective case-control study.

Linking Patient-Reported Outcome Measure Scores to Adverse Event Data to Gain Insight into Overestimation of Postoperative Patient-Reported Outcome Measure Improvement After Total Hip Arthroplasty and Total Knee Arthroplasty Due to Selective Nonresponse

BackgroundThe purpose of the study was to gain insight into how clinically relevant improvement in patient-reported outcome measure scores after total hip arthroplasty (THA) and total knee arthroplasty (TKA) may be underestimated or overestimated, we compared patient-reported outcome measure respondents and nonrespondents on their adverse event rates and assessed whether adverse event occurrence was associated with clinically relevant patient-reported outcome measure improvement from those without adverse events. MethodsAll primary THAs and TKAs performed in 19 Dutch hospitals between January 2017 and December 2019 were included. The hip disability and osteoarthritis outcome score-physical function short form (HOOS-PS) and knee injury and osteoarthritis outcome score-physical function short form (KOOS-PS) were used to assess the physical function after THA and TKA, respectively. Adverse events included 1-year revision, 30-day readmission, 30-day complications, and long (ie, >75th percentile) length of stay. A clinically relevant improvement was defined as at least a 10-point decrease in HOOS-PS and 9 points in KOOS-PS scores. Associations between adverse events and clinically relevant HOOS-PS and KOOS-PS improvement were assessed using binary logistic regression models adjusted for patient characteristics and clustering of patients within hospitals. ResultsThere were 20,338 THA and 18,082 TKA procedures included. Adverse events occurred more frequently in HOOS-PS and KOOS-PS nonrespondents than in respondents. The THA patients experiencing revision, complications, or long length of stay were less likely to experience clinically relevant HOOS-PS improvements (odds ratios of 0.11 [0.06 to 0.20], 0.44 [0.30 to 0.63], and 0.66 [0.50 to 0.88], respectively). The TKA patients experiencing revision or long length of stay were less likely to experience clinically relevant KOOS-PS improvements (odds ratios of 0.26 [0.12 to 0.55] and 0.63 [0.50 to 0.80], respectively). ConclusionsClinically relevant HOOS-PS and KOOS-PS improvements are likely overestimated, as nonrespondents had higher adverse event rates which were associated with lower likelihood to achieve clinically relevant HOOS-PS and KOOS-PS improvements.

Poster 345: External Validation of the Norwegian Anterior Cruciate Ligament Reconstruction Revision Prediction Model Using Patients From the Stability 1 Trial

Objectives: Machine learning has emerged as a potential tool for improving outcome prediction accuracy in anterior cruciate ligament (ACL) reconstruction (ACLR). A machine learning-based ACL revision prediction model has been developed using data from the Norwegian Knee Ligament Register (NKLR) but lacks external validation outside of Scandinavia. This study aimed to assess the external validity of the previously published ACL revision prediction model ( https://swastvedt.shinyapps.io/calculator_rev/ ) using data from the Stability 1 randomized clinical trial. The hypothesis was that the model's performance would be similar, indicating validity of the algorithm. Methods: This was a level 3 cohort study. The Cox Lasso prediction model from the original study was selected for external validation owing to its superior performance during model development and internal validation testing. The Stability 1 trial was an external randomized controlled trial that assigned patients to receive either hamstring tendon (HT) autograft or HT with lateral extra-articualr tenodesis (LET). Patients from Stability 1 with all 5 predictors required by the Cox Lasso model were included. Since all patients in the Stability 1 trial received hamstring HT plus/minus LET, three configurations were tested: 1: all patients coded as HT, 2: HT + LET group coded as bone-patellar tendon-bone (BPTB) autograft, 3: HT + LET group coded as unknown/other graft choice. The different configurations were tested because previous evaluation of the Stability 1 cohort by the Multicenter Orthopaedic Outcomes Network (MOON) suggests failure rates of HT + LET are most similar to the failure rates of patients who receive BPTB. Concordance and calibration were calculated to determine model performance with censoring of the time-to-event outcome. Results: In total, 591 patients from the Stability 1 trial were included, and 39 patients (6.6%) underwent revision surgery within 2 years. Model performance was best when patients randomized to HT + LET were coded as BPTB. Validation concordance was similar to the original NKLR prediction model for 1- and 2-year revision prediction (Stability: 0.71; NKLR: 0.68-0.69). Concordance CI ranged from 0.63-0.79. The model was well calibrated for 1-year prediction while the 2-year prediction demonstrated evidence of miscalibration. Conclusions: The most important finding of this study was that when patients in the Stability 1 trial who received HT + LET were coded as BPTB in the Norwegian prediction calculator, the model concordance was similar to the index study. However, the CI for the validation set was wider than the original model, suggesting that more data is required to definitively determine the external validity. The finding that HT + LET behaved most similarly to BPTB supports the notion that the addition of LET can decrease the failure and subsequent revision rate of primary ACLR when HT is used. In addition, if further external validation efforts are consistent with this study, the prediction model may require updating to equate HT + LET to BPTB for the purposes of prospectively estimating revision surgery risk.

How Has the Total Hip Arthroplasty Patient Population Changed? A Ten-Year Analysis of Total Hip Arthroplasty Patients From 2013 to 2022: A Retrospective, Single-Center Study

BackgroundOver the past decades, utilization of total hip arthroplasty (THA) has steadily increased. Understanding the demographic trends of THA patients can assist in projecting access to care. This study sought to assess the temporal trends in THA patient baseline characteristics and socioeconomic factors. MethodsWe retrospectively analyzed 16,296 patients who underwent primary elective THA from January 1, 2013, to December 31, 2022. Demographic data, including age, sex, race, body mass index (BMI), Charlson comorbidity index, insurance, and socioeconomic status, as determined by median income by patients’ zip code, were collected. The trends of these data were analyzed using the Mann-Kendall test. ResultsOver the past decade at our institution, patient age (2013: 62.1 years to 2022: 65.1 years, P = .001), BMI (2013: 29.0 to 2022: 29.5, P = .020), and mean Charlson comorbidity index (2013: 2.4 to 2022: 3.1, P = .001) increased. The proportion of Medicare patients increased from 48.4% in 2013 to 54.9% in 2022 (P = .001). The proportion of African American patients among the THA population increased from 11.3% in 2013 to 13.0% in 2022 (P = .012). Over this period, 90-day readmission and 1-year revision rates did not significantly change (2013: 4.8 and 3.0% to 2022: 3.4 and 1.4%, P = .107 and P = .136, respectively). The proportion of operations using robotic devices also significantly increased (2013: 0% to 2022: 19.1%; P < .001). ConclusionsIn the past decade, the average age, BMI, and comorbidity burden of THA patients have significantly increased, suggesting improved access to care for these populations. Similarly, there have been improvements in access to care for African American patients. Along with these changes in patient demographics, we found no change in 90-day readmission or 1-year revision rates. Continued characterization of the THA patient population is vital to understanding this demographic shift and educating future strategies and improvements in patient care.

A High Grade of Postoperative Knee Laxity Is Associated With an Increased Hazard of Revision Surgery: A Cohort Study of 4697 Patients With Primary ACL Reconstruction

Background: There is still debate regarding the association between arthrometric knee laxity measurements and subjective knee outcome and revision surgery after primary anterior cruciate ligament reconstruction (ACLR). Purpose: To assess whether arthrometric knee laxity (measured with the KT-1000 arthrometer) 6 months after primary ACLR was associated with the 1-, 2-, and 5-year subjective knee outcomes or revision ACLR at a 5-year follow-up. Study Design: Cohort study, Level of evidence 3. Methods: Patients who underwent primary ACLR with a hamstring tendon autograft at the authors’ institution between January 1, 2005, and December 31, 2017, with no concomitant ligamentous injuries, were identified. Anterior knee laxity (KT-1000 arthrometer, 134 N) was assessed 6 months postoperatively. The Knee injury and Osteoarthritis Outcome Score (KOOS) was collected preoperatively and 1, 2, and 5 years postoperatively. Patients who underwent revision ACLR at any institution in the country within 5 years of primary surgery were identified through the Swedish National Knee Ligament Registry. Results: A total of 4697 patients (54.3% male) with available KT-1000 arthrometer measurements were included (normal: side-to-side [STS] ≤2 mm, 3015 [64.2%]; nearly normal: STS 3-5 mm, 1446 [30.8%]; abnormal: STS >5 mm, 236 [5.0%]). The only significant difference in subjective knee outcome between the groups was for the KOOS Symptoms subscale at the 1-year follow-up (STS ≤2 mm, 79.9 ± 16.2; STS 3-5 mm, 82.5 ± 14.8; STS >5 mm, 85.1 ± 14.2; P < .001). No other significant differences between the groups were found preoperatively or at 1, 2, or 5 years postoperatively for any of the KOOS subscales. The hazard for revision ACLR within 5 years of the primary surgery was significantly higher for the groups with an STS of 3 to 5 mm (6.6%; 95/1446) (hazard ratio [HR], 1.42; 95% CI, 1.07-1.87; P = .01) and an STS >5 mm (11.4%; 27/236) (HR, 2.61; 95% CI, 1.69-4.03; P < .001) compared with the group with an STS ≤2 mm (3.8%; 116/3015). Conclusion: A high grade of postoperative knee laxity (STS 3-5 mm and STS >5 mm) 6 months after primary ACLR was associated with an increased hazard of revision ACLR within 5 years, but it was not associated with an inferior subjective knee outcome.

Periprosthetic Joint Infection After Total Knee Arthroplasty With or Without Antibiotic Bone Cement

Despite increased use of antibiotic-loaded bone cement (ALBC) in joint arthroplasty over recent decades, current evidence for prophylactic use of ALBC to reduce risk of periprosthetic joint infection (PJI) is insufficient. To compare the rate of revision attributed to PJI following primary total knee arthroplasty (TKA) using ALBC vs plain bone cement. This international cohort study used data from 14 national or regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, New Zealand, Norway, Romania, Sweden, Switzerland, the Netherlands, the UK, and the US. The study included primary TKAs for osteoarthritis registered from January 1, 2010, to December 31, 2020, and followed-up until December 31, 2021. Data analysis was performed from April to September 2023. Primary TKA with ALBC vs plain bone cement. The primary outcome was risk of 1-year revision for PJI. Using a distributed data network analysis method, data were harmonized, and a cumulative revision rate was calculated (1 - Kaplan-Meier), and Cox regression analyses were performed within the 10 registries using both cement types. A meta-analysis was then performed to combine all aggregated data and evaluate the risk of 1-year revision for PJI and all causes. Among 2 168 924 TKAs included, 93% were performed with ALBC. Most TKAs were performed in female patients (59.5%) and patients aged 65 to 74 years (39.9%), fully cemented (92.2%), and in the 2015 to 2020 period (62.5%). All participating registries reported a cumulative 1-year revision rate for PJI of less than 1% following primary TKA with ALBC (range, 0.21%-0.80%) and with plain bone cement (range, 0.23%-0.70%). The meta-analyses based on adjusted Cox regression for 1 917 190 TKAs showed no statistically significant difference at 1 year in risk of revision for PJI (hazard rate ratio, 1.16; 95% CI, 0.89-1.52) or for all causes (hazard rate ratio, 1.12; 95% CI, 0.89-1.40) among TKAs performed with ALBC vs plain bone cement. In this study, the risk of revision for PJI was similar between ALBC and plain bone cement following primary TKA. Any additional costs of ALBC and its relative value in reducing revision risk should be considered in the context of the overall health care delivery system.

Association between immigration status and total knee arthroplasty outcomes in Ontario, Canada: a population-based matched cohort study.

Immigrants and refugees face unique challenges navigating the health care system to manage severe arthritis, because of unfamiliarity, lack of awareness of surgical options, or access. The purpose of this study was to assess total knee arthroplasty (TKA) uptake, surgical outcomes, and hospital utilization among immigrants and refugees compared with Canadian-born patients. We included all adults undergoing primary TKA from January 2011 to December 2020 in Ontario. Cohorts were defined as Canadian-born or immigrants and refugees. We assessed change in yearly TKA utilization for trend. We compared differences in 1-year revision, infection rates, 30-day venous thromboembolism (VTE), presentation to emergency department, and hospital readmission between matched Canadian-born and immigrant and refugee groups. We included 158 031 TKA procedures. A total of 11 973 (7.6%) patients were in the immigrant and refugee group, and 146 058 (92.4%) patients were in the Canadian-born group. The proportion of TKAs in Ontario performed among immigrants and refugees nearly doubled over the 10-year study period (p < 0.001). After matching, immigrants were at relatively lower risk of 1-year revision (0.9% v. 1.6%, p < 0.001), infection (p < 0.001), death (p = 0.004), and surgical complications (p < 0.001). No differences were observed in rates of 30-day VTE or length of hospital stay. Immigrants were more likely to be discharged to rehabilitation (p < 0.001) and less likely to present to the emergency department (p < 0.001) than Canadian-born patients. Compared with Canadian-born patients, immigrants and refugees have favourable surgical outcomes and similar rates of resource utilization after TKA. We observed an underutilization of these procedures in Ontario relative to their proportion of the population. This may reflect differences in perceptions of chronic pain or barriers accessing arthroplasty.

Understanding the Influence of Single Payer Health Insurance on Socioeconomic Disparities in Total Hip Arthroplasty (THA) Utilization: A Transnational Analysis.

Access to care varies between countries. It is theorized that income-based disparities in access may be reduced in countries with universal health insurance relative to the United States, but data are currently limited. We hypothesized that income-based differences in total hip arthroplasty (THA) utilization and outcomes would be larger in the United States than in Canada. We retrospectively compared all patients undergoing THA from 2012 to 2018 in Pennsylvania, the United States, and Ontario, Canada. We compared age-standardized and sex-standardized per-capita THA utilization in the United States and Canada overall and across different income strata, where income strata were defined by neighborhood income quintile. We also examined income-based differences in rates of 1-year revision, 90-day mortality, and 90-day readmission. Overall THA utilization per 10,000 people per year was higher across all income groups in Pennsylvania compared with Ontario (15.1 versus 8.8, P < 0.001 in lowest-income quintile; 21.4 versus 12.6, P < 0.001 in highest-income quintile). Income-based differences in utilization in the highest-income vs lowest-income quintile groups were greater in Ontario (43.2%) than Pennsylvania (41.7%). The adjusted odds for the lowest-income group compared with the highest-income group of 1-year revision were greater in Ontario compared with Pennsylvania ( P = 0.03), and risk of 90-day mortality and 90-day readmission was similar between the regions. Income-based differences in THA utilization were more notable in Ontario than in Pennsylvania. In addition, patients in low-income communities in Ontario were at equal or greater risk relative to high-income community patients for adverse outcomes compared with patients in Pennsylvania. Income-based disparities in THA utilization and outcomes were smaller in the United States than in Canada, in contrast to what might be expected. III.

Non-Tobacco Nicotine Dependence and Rates of Postoperative Complications in Total Knee Arthroplasty: A Propensity-Matched Comparison.

Tobacco use elevates the incidence of postoperative complications and remains a key modifiable risk factor of perioperative surgical optimization. It remains unclear whether non-tobacco nicotine dependence confers an increased risk of surgical complications. This study evaluates postoperative complications in patients with non-tobacco nicotine dependence for total knee arthroplasty (TKA). We queried the TriNetX health database using Current Procedural Terminology and International Classification of Diseases, 10th Revision (ICD-10) codes and identified two cohorts for evaluation. Cohort A was defined as patients who had a TKA; had a dependence on nicotine; did not have nicotine dependence to cigarettes, chewing tobacco, other tobacco products; and were between the ages of 35 and 90 years. Cohort B was defined as patients who had a TKA but did not have a dependence on nicotine or a personal history of nicotine dependence and were between the ages of 35 and 90 years. This study analyzed a total of 10,594 non-tobacco nicotine-dependent patients and 175,079 non-dependent patients who underwent TKA. In the analysis of propensity-matched cohorts, non-tobacco nicotine-dependent patients demonstrated an increased rate of various postoperative complications within 90 days. Dependent patients saw a significantly increased risk of infection after a procedure (P < 0.001), deep vein thrombosis (P < 0.001), pulmonary embolism (P < 0.001), sepsis (P = 0.0065), and prosthetic joint infection (P = 0.0361) and a higher 3-year revision rate (P = 0.0084). Non-tobacco nicotine dependence demonstrated an increased associated risk of postoperative surgical complications for patients undergoing TKA. Orthopaedic surgeons should consider evaluating non-tobacco nicotine dependence within their surgical optimization protocol. Level III, Prognostic.