No Difference in Survivorship Following Primary Total Hip Arthroplasty Using Ultra-Porous Acetabular Cups and Crosslinked Polyethylene With and Without Acetabular Screws in a Large US Healthcare System.

INTRODUCTION: Modern cementless acetabular cups for total hip arthroplasty (THA) typically have screw options. Historically, screws were thought to improve stability, but came at the cost of pathways for osteolysis. Modern cups and liners may have made both concerns obsolete, and the utility of screws are now contested. We sought to determine modern implant survivorship relative to screw use. METHODS: We conducted a cohort study. A US healthcare system's Total Joint Replacement Registry was used to identify patients ≥18 years who underwent uncomplicated primary THA for osteoarthritis (2010 to 2021) with an ultra-porous cup and cross-linked polyethylene liner, with- or without one to two acetabular screws. The primary outcome was acetabular revision for aseptic loosening. Secondary outcomes were aseptic revision for acetabular fracture and any revision for acetabular/femoral loosening and periprosthetic fracture. Multiple Cox proportional hazard regression was used to evaluate revision risk. There were 46,785 THAs identified. Screw use declined from 65.3 to 49.9%. RESULTS: No difference was observed in 10-year revision risk for acetabular loosening (0.2 versus 0.1%, hazard ratio [HR] 1.97, 95% confidence interval [CI] = 0.84 to 4.59, P = 0.119). There was one revision for acetabular fracture with and three revisions without screws. There was no difference in risk of overall acetabular or femoral revision, loosening, or periprosthetic fracture. There remained no difference in acetabular-sided loosening between routine screw users and non-users (0.15 versus 0.06%, HR 1.26, 95% CI 0.42 to 3.75, P = 0.683). CONCLUSIONS: In this study of survivorship following routine uncomplicated primary THA with modern cups and liners, screw usage patterns were associated with neither an advantage nor disadvantage - neither screw usage nor avoidance was associated with differences in acetabular loosening revision risk. Screw use was not associated with harm but remains debatable if there is an added benefit.

Dual-Mobility Articulations in Revision Total Hip Arthroplasty: A Comparison with Metal or Ceramic on Highly Cross-Linked Polyethylene and Constrained Articulations.

BACKGROUND: The increased availability of dual-mobility acetabular constructs (DMCs) provides surgeons with a newer option to increase the effective femoral head size in revision total hip arthroplasty (rTHA). We sought to evaluate risks of re-revision and prosthetic dislocation following rTHA involving a DMC compared with other articulations. METHODS: A cohort study was conducted using data from a U.S. integrated health-care system's Total Joint Replacement Registry. Adult patients who underwent primary THA and went on to undergo an aseptic rTHA in 2002 to 2022 were identified. Patients who received a DMC, a constrained liner, or a metal or ceramic unipolar femoral head on highly cross-linked polyethylene (XLPE) at the time of rTHA were the treatment groups. Subsequent aseptic re-revision and dislocation were the outcomes of interest. Multivariable Cox proportional-hazards regression was used to evaluate the risks of the outcomes, with adjustment for patient, operative, and surgeon confounders. RESULTS: The analyzed rTHAs comprised 375 with a DMC, 268 with a constrained liner, 995 with a <36-mm head on XLPE, and 2,087 with a ≥36-mm head on XLPE. DMC utilization increased from 1.0% of rTHAs in 2011 to 21.6% in 2022. In adjusted analyses, a higher re-revision risk was observed for the constrained liner (hazard ratio [HR] = 2.43, 95% confidence interval [CI] = 1.29 to 4.59), <36 mm on XLPE (HR = 2.05, 95% CI = 1.13 to 3.75), and ≥36 mm on XLPE (HR = 2.03, 95% CI = 1.19 to 3.48) groups compared with the DMC group. A higher dislocation risk was observed in both XLPE groups (<36 mm: HR = 2.04, 95% CI = 1.33 to 3.14; ≥36 mm: HR = 2.46, 95% CI = 1.69 to 3.57) compared with the DMC group; a nonsignificant trend toward a higher dislocation rate in the group with a constrained liner than in the DMC group was also observed. CONCLUSIONS: In a large U.S.-based cohort, rTHAs using DMCs had the lowest re-revision risk and dislocation risk. Both outcomes were significantly lower than those using a unipolar femoral head on XLPE, re-revision risk was significantly lower than using a constrained liner, and dislocation risk trended toward a lower risk than using a constrained liner. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Loose fit versus press fit stems and risk for surgical reintervention following radial head arthroplasty: A US-based cohort study of 1575 patients.

INTRODUCTION: Radial head arthroplasty (RHA) is performed with increasing frequency for reconstruction of comminuted radial head fractures. Implants can be categorized by stem design, either loose fit or press fit. Currently, the RHA literature does not suggest one implant type is superior to another based on revision and reoperation rates, although most RHA outcome studies have small numbers of patients with few events to detect a difference. This study evaluated the association between stem design and risk of revision and reoperation after RHA. METHODS: 1575 patients aged ≥18 years who underwent primary RHA within a US-based healthcare system were identified (2009-2021). Revision following the index RHA was the primary outcome of interest; ipsilateral reoperation was a secondary outcome. Multivariable Cox proportional hazard regression was used to evaluate the risk of outcomes by loose versus press fit with the adjustment for race/ethnicity, ASA classification, region, surgeon RHA volume, and simultaneous ipsilateral extremity procedures. RESULTS: Of the 1575 RHA, 681 (43.2%) received a loose fit stem. The cumulative revision probability was 2.6% for loose fit and 3.5% for press fit. In adjusted analysis, we did not observe a difference in risk of revision (HR=0.78, 95% CI=0.41-1.46) or reoperation (HR=0.73, 95% CI=0.43-1.25). Additionally, there were no observed differences in risk of revision (HR=0.62, 95% CI=0.28-1.38) or reoperation (HR=0.90, 95% CI=0.48-1.71) in the patient subgroup who underwent additional procedures in the same extremity at the time of RHA. CONCLUSION: In this large multi-center cohort of 1575 primary RHA, we did not observe a difference in risk of revision or reoperation following RHA based upon stem design. The choice between using an implant with a loose or press fit stem may be based more on surgeon familiarity, implant availability and cost, and ease of use.

Patient and Operative Risk Factors for Osteoarthritis After Primary Anterior Cruciate Ligament Reconstruction: A Cohort Study of 41,976 Patients.

BACKGROUND: The reported incidence of posttraumatic knee osteoarthritis (PTOA) after primary anterior cruciate ligament reconstruction (ACLR) varies considerably. Further, there are gaps in identifying which patients are at risk for PTOA after ACLR and whether there are modifiable factors. PURPOSE: To (1) determine the incidence of PTOA in a primary ACLR cohort and (2) identify patient and perioperative factors associated with the development of PTOA after primary ACLR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Data from the Kaiser Permanente ACLR Registry were used to conduct a cohort study. Patients who had undergone primary ACLR without a previous diagnosis of osteoarthritis were identified (2009-2020). The crude incidence of PTOA was calculated using the Aalen-Johansen estimator with a multistate model. The association of patient and operative factors with the development of PTOA after primary ACLR was modeled as a time to event using multistate Cox proportional hazards regression. Models stratified by age (<22 and ≥22 years) were also conducted because of the effect modification of age. RESULTS: The study sample included 41,976 cases of primary ACLR. The incidence of PTOA was 1.7%, 5.1%, and 13.6% at 2, 5, and 10 year follow-ups, respectively. Risk factors for PTOA that were consistently identified in the overall cohort and age-stratified groups included a body mass index ≥30 versus <30 and an allograft or quadriceps tendon autograft versus a hamstring tendon autograft. Patients presenting with knee pain after ACLR were further identified when considering postoperative factors. Other risk factors for PTOA in the overall cohort included age ≥22 versus <22 years, bone-patellar tendon-bone autograft versus hamstring tendon autograft, hypertension, cartilage injury, meniscal injury, revision after primary ACLR with concomitant meniscal/cartilage surgery, multiligament injury, other activity at the time of injury compared with sport, and tibial tunnel drilling technique rather than the anteromedial portal. CONCLUSION: Knee pain after ACLR may be an early sign of PTOA. Surgeons should consider the adverse associations of a higher body mass index and an allograft or quadriceps tendon autograft with the development of PTOA, as these were factors identified with a higher risk, regardless of a patient's age at the time of primary ACLR.

Are There Differences in Performance Among Femoral Stem Brands Utilized in Cementless Hemiarthroplasty for Treatment of Geriatric Femoral Neck Fractures?

BACKGROUND: For the vast majority of displaced femoral neck fractures in older patients, cemented femoral fixation is indicated because it is associated with a lower risk of periprosthetic fracture than cementless fixation. Nevertheless, cementless fixation continues to be utilized with high frequency for hip fractures in the United States. It is therefore helpful to understand the performance of individual cementless brands and models. Although prior studies have compared femoral stems by design type or stem geometry, there may still be a difference in revision risk according to femoral stem brand given the potential differences within design groupings with regard to manufacturing, implantation systems, and implant design nuances among vendors. QUESTIONS/PURPOSES: (1) Is there a difference in aseptic revision risk among femoral stem brands in patients ≥ 60 years of age who have displaced femoral neck fractures treated with cementless hemiarthroplasty? (2) Is there a difference in revision for periprosthetic fracture among femoral stem brands in patients ≥ 60 years of age with displaced femoral neck fractures treated with cementless hemiarthroplasty? METHODS: A retrospective, comparative, large-database cohort study was conducted using data from Kaiser Permanente's Hip Fracture Registry. This integrated healthcare system covers more than 12 million members throughout eight regions in the United States; membership has been found to be representative of the general population in the areas served. The Hip Fracture Registry collects details on all patients who undergo hip fracture repair within the organization. These patients are then longitudinally monitored for outcomes after their repair, and all identified outcomes are manually validated through chart review. Patients ages ≥ 60 years who underwent unilateral hemiarthroplasty treatment of a displaced femoral neck fracture from 2009 to 2021 were identified (n = 22,248). Hemiarthroplasties for polytrauma, pathologic or open fractures, or patients who had additional surgeries at other body sites during the same stay, as well as those with prior procedures in the same hip, were excluded (21.4% [4768]). Cemented procedures and those with missing or inconsistent implant information (for example, cement used but cementless implant recorded) were further excluded (47.1% [10,485]). To allow for enough events for evaluation, the study sample was restricted to seven stems for which there were at least 300 hemiarthroplasties performed, including four models from DePuy Synthes (Corail®, Summit®, Summit Basic, and Tri-Lock®) and three from Zimmer Biomet (Medial-Lateral [M/L] Taper®, Trabecular Metal®, and Versys® Low Demand Fracture [LD/FX]). The final sample included 5676 cementless hemiarthroplasties: 653 Corail, 402 M/L Taper, 1699 Summit, 1590 Summit Basic, 384 Tri-Lock, 637 Trabecular Metal, and 311 Versys LD/FX. Procedures were performed by 396 surgeons at 35 hospitals. The mean age and BMI for the cohort was 81 years and 24 kg/m2, respectively; most were women (66% [3733 of 5676]) and White (79% [4488 of 5676]). Based on standardized mean differences, we controlled for age, race/ethnicity, American Society of Anesthesiologist (ASA) classification, anesthesia technique, operative year, average annual surgeon hemiarthroplasty volume, and operative year across the seven stem groups. Of the 5676 patients, 7% (378 of 5676) were lost to follow-up through membership termination at a median time of 1.6 years, and 56% (3194 of 5676) of the patients died during study follow-up. A multivariable cause-specific Cox proportional hazards regression model was used to evaluate the risk for aseptic revision with adjustment for age, gender, ASA classification, depression, operating surgeon, deficiency anemias, time from admission to surgery, and average annual surgeon hemiarthroplasty volume. A random intercept was included to address effects from hemiarthroplasties performed by the same surgeon. Risk for revision for periprosthetic fracture was also evaluated as a secondary outcome. RESULTS: In the adjusted analysis, the Summit Basic (HR 1.91 [95% confidence interval 1.34 to 2.72]; p < 0.001), the M/L Taper (HR 1.91 [95% CI 1.15 to 3.15]; p = 0.01), and the Versys LD/FX (HR 2.12 [95% CI 1.25 to 3.61]; p = 0.005) had higher aseptic revision risks during follow-up when compared with the Summit. No differences were observed for the Corail (HR 0.57 [95% CI 0.29 to 1.10]; p = 0.09), the Tri-Lock (HR 1.13 [95% CI 0.62 to 2.07]; p = 0.68), or the Trabecular Metal (HR 1.14 [95% CI 0.69 to 1.89]; p = 0.61) compared with the Summit. A higher risk for revision because of periprosthetic fracture was observed with the M/L Taper (HR 2.43 [95% CI 1.29 to 4.58]; p = 0.006) and the Summit Basic (within 3 months of follow-up: HR 1.16 [95% CI 0.60 to 2.25]; p = 0.66; after 3 months of follow-up: HR 2.84 [95% CI 1.36 to 5.94]; p = 0.006) stems when compared with the Summit. CONCLUSION: In a cohort of 5676 cementless hemiarthroplasties, we found differences in revision risks among different femoral stem brands. Based on our findings, we recommend against utilization of the Zimmer M/L Taper, DePuy Summit Basic, and Zimmer Versys LD/FX in the treatment of displaced geriatric femoral neck fractures with cementless hemiarthroplasty. Future large registry studies are needed to further elucidate differences in aseptic revision risk among higher performing cementless femoral stems. Although cemented fixation remains the recommended approach based on the best available evidence in hemiarthroplasty treatment of hip fractures, our findings may help to mitigate aseptic revision risk should cementless fixation be chosen. LEVEL OF EVIDENCE: Level III, therapeutic study.

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

Importance: 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. Objective: To compare the rate of revision attributed to PJI following primary total knee arthroplasty (TKA) using ALBC vs plain bone cement. Design, Setting, and Participants: 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. Exposure: Primary TKA with ALBC vs plain bone cement. Main Outcomes and Measures: 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. Results: 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. Conclusions and Relevance: 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.

Improvements in Quality, Safety and Costs Associated with Use of Implant Registries Within a Health System.

BACKGROUND: Clinical quality registries (CQRs) are intended to enhance quality, safety, and cost reduction using real-world data for a self-improving health system. Starting in 2001, Kaiser Permanente established several medical device CQRs as a quality improvement initiative. This report examines the contributions of these CQRs on improvement in health outcomes, changes in clinical practice, and cost-effectiveness over the past 20 years. METHODS: Eight implant registries were instituted with standardized collection from the electronic health record and other institutional data sources of patient characteristics, medical comorbidities, implant attributes, procedure details, surgical techniques, and outcomes (including complications, revisions, reoperations, hospital readmissions, and other utilization measures). A rigorous quality control system is in place to improve and maintain the quality of data. Data from the Implant Registries form the basis for multiple quality improvement and patient safety initiatives to minimize variation in care, promote clinical best practices, facilitate recalls, perform benchmarking, identify patients at risk, and construct reports about individual surgeons. RESULTS: Following the inception of the Implant Registries, there was an observed (1) reduction in opioid utilization following orthopedic procedures, (2) reduction in use of bone morphogenic protein during lumbar fusion allowing for cost savings, (3) reduction in allograft for anterior cruciate ligament reconstruction and subsequent decrease in organizationwide revision rates, (4) cost savings through expansion of same-day discharge programs for joint arthroplasty, (5) increase in the use of cement fixation in the hemiarthroplasty treatment of hip fracture, and (6) organizationwide discontinuation of an endograft device associated with a higher risk for adverse outcomes following endovascular aortic aneurysm repair. CONCLUSION: The use of Implant Registries within our health system, along with clinical leadership and organizational commitment to a learning health system, was associated with improved quality and safety outcomes and reduced costs. The exact mechanisms by which such registries affect health outcomes and costs require further study.

Unipolar Hemiarthroplasty, Bipolar Hemiarthroplasty, or Total Hip Arthroplasty for Hip Fracture in Older Individuals.

BACKGROUND: Practice patterns regarding the use of unipolar hemiarthroplasty, bipolar hemiarthroplasty, and total hip arthroplasty (THA) for femoral neck fractures in older patients vary widely. This is due in part to limited data stipulating the specific circumstances under which each form of arthroplasty provides the most predictable outcome. The purpose of this study was to investigate the patient characteristics for which unipolar hemiarthroplasty, bipolar hemiarthroplasty, or THA might be preferable due to a lower risk of all-cause revision. METHODS: A U.S. health-care system's hip fracture registry was used to identify patients ≥60 years old who underwent unipolar hemiarthroplasty, bipolar hemiarthroplasty, or THA for hip fracture from 2009 through 2021. Unipolar and bipolar hemiarthroplasty were compared with THA within patient subgroups defined by age (60 to 79 versus ≥80 years) and American Society of Anesthesiologists (ASA) classification (I or II versus III); patients with an ASA classification of IV or higher were excluded. Multivariable Cox proportional hazard regression analysis was used to evaluate all-cause revision risk while adjusting for confounders, with mortality considered as a competing risk. RESULTS: There were 14,277 patients in the final sample (median age, 82 years; 70% female; 80% White; 69% with an ASA classification of III; median follow-up, 2.7 years), and the procedures included 7,587 unipolar hemiarthroplasties, 5,479 bipolar hemiarthroplasties, and 1,211 THAs. In the multivariable analysis of all patients, both unipolar (hazard ratio [HR] = 2.15, 95% confidence interval [CI] = 1.48 to 3.12; p < 0.001) and bipolar (HR = 1.92, 95% CI = 1.31 to 2.80; p < 0.001) hemiarthroplasty had higher revision risks than THA. In the age-stratified multivariable analysis of patients aged 60 to 79 years, both unipolar (HR = 2.17, 95% CI = 1.42 to 3.34; p = 0.004) and bipolar (HR = 1.69, 95% CI = 1.08 to 2.65; p = 0.022) hemiarthroplasty also had higher revision risks than THA. In the ASA-stratified multivariable analysis, patients with an ASA classification of I or II had a higher revision risk after either unipolar (HR = 3.52, 95% CI = 1.87 to 6.64; p < 0.001) or bipolar (HR = 2.31, 95% CI = 1.19 to 4.49; p = 0.013) hemiarthroplasty than after THA. No difference in revision risk between either of the hemiarthroplasties and THA was observed among patients with an age of ≥80 years or those with an ASA classification of III. CONCLUSIONS: In this study of hip fractures in older patients, THA was associated with a lower risk of all-cause revision compared with unipolar and bipolar hemiarthroplasty among patients who were 60 to 79 years old and those who had an ASA classification of I or II. LEVEL OF EVIDENCE: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Can Dual Mobility Cups Reduce Revision and Dislocation Risks? An Analysis of 107,528 Primary Total Hip Arthroplasties in the United States.

BACKGROUND: Dual mobility acetabular cups (DMC) were designed to increase the effective femoral head size and improve stability with the goal of reducing revision risk at the potential cost of polyethylene thickness. We sought to evaluate revision risk following primary elective total hip arthroplasty with DMC compared to highly cross-linked polyethylene (XLPE). METHODS: A cohort study was conducted using data from a Kaiser Permanente's total joint arthroplasty registry. Patients ≥18 years who underwent primary elective total hip arthroplasty using DMC, unipolar Metal-on-XLPE (MoXLPE), or unipolar Ceramic-on-XLPE (CoXLPE) were identified (2010 to 2021). The final sample comprised 2,219 DMC, 48,251 MoXLPE, and 57,058 CoXLPE. Multiple Cox proportional hazard regressions were used to evaluate aseptic revision and any dislocation regardless of revision within 6 years follow-up. RESULTS: In adjusted analyses, no differences in aseptic revision risk were observed for MoXLPE (hazard ratio [HR] = 1.04, 95% confidence interval [CI] = 0.72 to 1.51) or CoXLPE (HR = 0.98, 95% CI = 0.69 to 1.40) compared to DMC. No differences in dislocation risk were observed for MoXLPE (HR = 1.42, 95% CI = 0.93 to 2.15) or CoXLPE (HR = 1.25, 95% CI = 0.84 to 1.87) compared to DMC. CONCLUSIONS: In a US-based cohort, 6-year aseptic revision risk of DMC was similar to metal or ceramic femoral head unipolar constructs. Furthermore, no difference in dislocation risk was observed. Continued longer-term follow-up may reveal if there is a reduced risk of dislocation that comes at the cost of increased late revision. LEVEL OF EVIDENCE: Level III.

The use of antibiotic-loaded bone cement and systemic antibiotic prophylactic use in 2,971,357 primary total knee arthroplasties from 2010 to 2020: an international register-based observational study among countries in Africa, Europe, North America, and Oceania.

BACKGROUND AND PURPOSE: Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA). PATIENTS AND METHODS: This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries. RESULTS: ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register). CONCLUSION: The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries.

Association Between Race/Ethnicity and 90-Day Emergency Department Visits in Patients Undergoing Elective Total Knee Arthroplasty or Total Hip Arthroplasty in a Universally Insured Population.

BACKGROUND: Research has identified disparities in returns to care by race/ethnicity following primary total joint arthroplasty. We sought to identify risk factors for 90-day emergency department (ED) returns following primary total knee arthroplasty (TKA) or total hip arthroplasty (THA) for these populations. METHODS: Black, Hispanic, and non-Hispanic White patients who underwent elective primary unilateral TKA and THA in an integrated US healthcare system were identified. Risk factors for 90-day postoperative ED visits including patient demographics, household income and education, comorbidities, preoperative healthcare utilization, and copay data were identified with multivariable logistic regression. RESULTS: Postoperative 90-day ED visits occurred in 13.3% of 79,565 TKA patients (17.2% Black; 14.9% Hispanic; 12.5% White) and 11.0% of THA patients (13.4% Black; 12.1% Hispanic; 10.7% White). Across racial/ethnic categories, patients who had an ED visit within 1 year of their TKA or THA date were more likely to have a 90-day ED return. Shared risk factors for TKA patients were chronic lung disease and outpatient utilization (25th and 75th percentile), while peripheral vascular disease was a shared risk factor for THA patients. Risk factors for multiple races of TKA and THA patients included depression, drug abuse, and psychosis. Prior copay for White (TKA) and Hispanic (TKA and THA) patients was protective, while preoperative primary care was protective for Black THA patients. CONCLUSION: Future strategies to reduce postoperative ED returns should include directed patient outreach for patients who had ED visits and mental health in the year prior to TKA and THA. LEVEL OF EVIDENCE: III.

Risk of Aseptic Revision and Periprosthetic Fracture Following Bipolar Versus Unipolar Hemiarthroplasty.

Hemiarthroplasty is currently the most common treatment for displaced femoral neck fractures in the elderly. While bipolar hemiarthroplasty was developed to reduce the risk of acetabular erosion that is associated with traditional unipolar hemiarthroplasty, meta-analyses have reported similar outcomes for bipolar and unipolar hemiarthroplasty devices. The primary objective of this study was to evaluate the risks of aseptic revision and periprosthetic fracture following bipolar versus unipolar hemiarthroplasty in a large integrated health-care system in the United States. Methods: We conducted a retrospective cohort study using data from the hip fracture registry of an integrated health-care system. Patients aged ≥60 years who underwent hemiarthroplasty for hip fracture between 2009 and 2019 were included. The primary outcome measure was aseptic revision, and the secondary outcome measure was revision for periprosthetic fracture. Cause-specific Cox proportional hazards regression was performed, with mortality considered as a competing event. In the multivariable analysis, estimates were adjusted for potential confounders such as age, sex, race/ethnicity, body mass index, American Society of Anesthesiologists classification, femoral fixation, surgeon volume, type of anesthesia, and discharge disposition. Results: The study sample included 13,939 patients who had been treated with hemiarthroplasty by 498 surgeons at 35 hospitals. The mean follow-up time was 3.7 ± 2.9 years. The overall incidence of aseptic revision at 5 years following hemiarthroplasty was 2.8% (386). In the multivariable analysis controlling for potential confounders, bipolar hemiarthroplasty was associated with a lower risk of aseptic revision than unipolar hemiarthroplasty (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.59 to 0.94; p = 0.012). Rates of revision for periprosthetic fracture were similar between the bipolar and unipolar devices (HR, 0.79; 95% CI, 0.58 to 1.10; p = 0.16). Conclusions: In this study of hemiarthroplasty for hip fracture in elderly patients, bipolar designs were associated with a lower risk of aseptic revision than unipolar designs. In contrast to prior research, we did not find any difference in the risk of periprosthetic fracture between the 2 designs. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Association between same-day discharge shoulder arthroplasty and risk of adverse events in patients with American Society of Anesthesiologists classification ≥3: a cohort study.

BACKGROUND: Same-day discharge for shoulder arthroplasty (SA) is well-supported in the literature; however, most studies have focused on healthier patients. Indications for same-day discharge SA have expanded to include patients with more comorbidities, but safety of same-day discharge in this population remains unknown. We sought to compare outcomes following same-day discharge vs. inpatient SA in a cohort of patients considered higher risk for adverse events, defined as an American Society of Anesthesiologists (ASA) classification of ≥3. METHODS: Data from Kaiser Permanente's SA registry were utilized to conduct a retrospective cohort study. All patients with an ASA classification of ≥3 who underwent primary elective anatomic or reverse SA in a hospital from 2018 to 2020 were included. The exposure of interest was in-hospital length of stay: same-day discharge vs. ≥1-night hospital inpatient stay. The likelihood of 90-day post-discharge events, including emergency department (ED) visit, readmission, cardiac complication, venous thromboembolism, and mortality, was evaluated using propensity score-weighted logistic regression with noninferiority testing using a margin of 1.10. RESULTS: The cohort included a total of 1814 SA patients, of whom 1005 (55.4%) had same-day discharge. In propensity score-weighted models, same-day discharge was not inferior to an inpatient stay SA regarding 90-day readmission (odds ratio [OR] = 0.64, one-sided 95% upper bound [UB] = 0.89) and overall complications (OR = 0.67, 95% UB = 1.00). We lacked evidence in support of noninferiority for 90-day ED visit (OR = 0.96, 95% UB = 1.18), cardiac event (OR = 0.68, 95% UB = 1.11), or venous thromboembolism (OR = 0.91, 95% UB = 2.15). Infections, revisions for instability, and mortality were too rare to evaluate using regression analysis. CONCLUSIONS: In a cohort of over 1800 patients with an ASA of ≥3, we found same-day discharge SA did not increase the likelihood of ED visits, readmissions, or complications compared with an inpatient stay, and same-day discharge was not inferior to an inpatient stay with regard to readmissions and overall complications. These findings suggest that it is possible to expand indications for same-day discharge SA in the hospital setting.

Risk for surgical interventions following endovascular aneurysm repair with Endologix AFX or AFX2 Endovascular AAA Systems compared with other devices.

OBJECTIVE: To evaluate the risk for 90-day returns to care and long-term subsequent surgical interventions after primary endovascular aneurysm repair (EVAR) with an Endologix AFX Endovascular AAA System compared with three other high-volume endograft devices. METHODS: We conducted a matched cohort study using data from Kaiser Permanente's Endovascular Stent Graft Registry. Patients aged ≥18 years who underwent primary EVAR for AAA in the health care system from January 1, 2011, to December 31, 2017, comprised the eligible study sample. The treatment group included patients who received an Endologix AFX or AFX2 device (n = 470). Patients who received one of three other high-volume endograft devices used within the health care system comprised the eligible comparison group (n = 2122). These patients were 2:1 propensity score matched without replacement to patients who received an Endologix device based on a number of patient and procedural characteristics. After the application of matching, conditional logistic regression was used to evaluate the likelihood for 90-day emergency department visit and readmission. Cause-specific Cox regression was used to evaluate the long-term risk of endoleak, graft revision, secondary reintervention (not including revision), conversion to open repair, and rupture during follow-up. Cox proportional hazards regression was used to evaluate the risk of mortality (overall and aneurysm related). RESULTS: The final matched study sample included 470 patients who received an Endologix AFX or AFX2 device and 940 patients who received a different high-volume device. compared with the other devices, AFX/AFX2 had a higher risk for type III endoleak (hazard ratio [HR], 38.79; 95% confidence interval [CI], 14.51-103.67), revision surgery >1 year after the primary EVAR (HR, 4.50; 95% CI, 3.10-6.54), rupture (HR, 6.52; 95% CI, 1.73-24.63), and aneurysm-related mortality (HR, 2.43; 95% CI, 1.32-4.47) was observed with the use of AFX/AFX2. CONCLUSIONS: In our matched cohort study, patients who received an Endologix AFX System during their primary EVAR had a higher risk for several adverse longitudinal outcomes, as well as aneurysm-related mortality, when compared with patients who received other high-volume devices. Patients who have received these devices should be monitored closely after EVAR.

Prolonged Opioid Usage Following Hip Fracture Surgery in Opioid-Naïve Older Patients.

BACKGROUND: While the risk of long-term dependence following the opioid treatment of musculoskeletal injury is often studied in younger populations, studies in older patients have centered on short-term risks such as oversedation and delirium. This study investigated prolonged opioid usage after hip fracture in older individuals, focusing on prevalence, risk factors, and changes over time. METHODS: In this retrospective cohort study of 47,309 opioid-naïve patients aged ≥ 60 years who underwent hip fracture surgery (2009 to 2020), outpatient opioid use was evaluated in 3 postoperative time periods: P1 (day 0 to 30 postsurgery); P2 (day 31 to 90); and P3 (day 91 to 180). The primary outcome was prolonged outpatient opioid use, defined as having one or more opioid prescriptions dispensed in all 3 time periods. RESULTS: The incidence of prolonged opioid usage among patients surviving to P3 was 6.3% (2,834 of 44,850). Initial prescription quantities decreased over time, as did the risk of prolonged opioid usage (from 8.0% in 2009 to 3.9% in 2019). In the multivariable analyses, risk factors for prolonged opioid usage included younger age, women, current/former smoking, fracture fixation (as compared to hemiarthroplasty), and anxiety. Prolonged opioid usage was less common among patients who were Asian or had a history of dementia. CONCLUSIONS: While prior research on the hazards of opioids in the elderly has focused on short-term risks such as oversedation and delirium, these findings suggest that prolonged opioid usage may be a risk for this older population as well. As initial prescription amounts have decreased, declines in prolonged opioid medication usage have also been observed.

An Interrupted Time Series Analysis Measuring the Impact of Research and Education on Clinical Practice: Decreasing Allograft Use in Young Patients Using a Registry to Track Outcomes.

BACKGROUND: We sought to evaluate whether allograft utilization for primary anterior cruciate ligament reconstruction (ACLR) within our health-care system changed following the implementation of an allograft reduction intervention and whether revision rates within the health-care system changed following the initiation of the intervention. METHODS: We conducted an interrupted time series study using data from Kaiser Permanente's ACL Reconstruction Registry. In our study, we identified 11,808 patients who were ≤21 years of age and underwent primary ACLR from January 1, 2007, through December 31, 2017. The pre-intervention period (15 quarters) was January 1, 2007, through September 30, 2010, and the post-intervention period (29 quarters) was October 1, 2010, through December 31, 2017. Poisson regression was used to evaluate trends over time in 2-year revision rates according to the quarter in which the primary ACLR was performed. RESULTS: Allograft utilization increased pre-intervention from 21.0% in 2007 Q1 to 24.8% in 2010 Q3. Utilization decreased post-intervention from 29.7% in 2010 Q4 to 2.4% in 2017 Q4. The quarterly 2-year revision rate increased from 3.0 to 7.4 revisions per 100 ACLRs pre-intervention and decreased to 4.1 revisions per 100 ACLRs by the end of the post-intervention period. Poisson regression found an increasing 2-year revision rate over time pre-intervention (rate ratio [RR], 1.03 [95% confidence interval (CI), 1.00 to 1.06] per quarter) and a decreasing rate over time post-intervention (RR, 0.96 [95% CI, 0.92 to 0.99]). CONCLUSIONS: In our health-care system, we saw a decrease in allograft utilization following the implementation of an allograft reduction program. During the same period, a decrease in the ACLR revision rate was observed. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Identification of implant outliers in joint replacement registries.

Recent concerns surrounding joint replacements that have a higher than expected rate of revision have led to stricter controls by regulatory authorities with regards to the introduction of new devices into the marketplace. Implant post-market surveillance remains important, and joint replacement registries are ideally placed to perform this role. This review examined if and how joint replacement registries identified outlier prostheses, outlined problems and suggested solutions to improve post-market surveillance. A search was performed of all joint replacement registries that had electronic or published reports detailing the outcomes of joint replacement. These reports were examined for registry identification of outlier prostheses. Five registries publicly identified outlier prostheses in their reports and the methods by which this was performed, and three others had internal reports. Identification of outlier prostheses is one area that may improve overall joint replacement outcomes; however, further research is needed to determine the optimum methods for identification, including the threshold, the comparator and the numbers required for notification of devices. Co-operation of registries at a global level may lead to earlier identification of devices and thereby further improve the results of joint replacement.

Single Wedge Femoral Stem Designs are Associated With a Higher Risk for Revision After Cementless Primary Total Hip Arthroplasty.

BACKGROUND: Cementless total hip arthroplasty (THA) femoral stems are the most commonly selected prostheses in the United States. Optimal stem geometry remains controversial with excellent survivorship reported for many designs. We compared cause-specific stem revision of single-wedge versus double-wedge designs from a multicenter US cohort. METHODS: Data from an integrated healthcare network's total joint replacement registry were used to conduct a cohort study. Primary elective cementless THAs were identified (2001 to 2018). Implant exposure groups were classified by design geometry using the system proposed by Khanuja et al. Type 1 single-wedge (n = 11,082) and type 2 double-wedge (n = 32,380) designs were compared, and other design types were excluded; the final study cohort comprised 43,462 THAs. Cause-specific multivariable Cox regressions were used to evaluate risk for revision due to infection or aseptic reasons, including loosening, instability, periprosthetic fracture, or other reasons. RESULTS: After adjustment for covariates, a higher aseptic revision risk was observed for type 1 when compared to type 2 designs (hazard ratio = 1.91, 95% confidence interval = 1.33-2.75). When looking at specific revision reasons, revision for aseptic loosening (hazard ratio = 3.46, 95% confidence interval = 2.24-5.34) was higher for type 1 versus type 2 designs. No differences were found for septic revision, instability, periprosthetic fracture, or revisions for other reasons. CONCLUSIONS: Type 1 single-wedge designs were found to have a higher risk of revision due to aseptic loosening relative to type 2 double-wedge designs. Femoral stem geometry should be considered when selecting a cementless femoral implant. LEVEL OF EVIDENCE: Level III.

Does Aseptic Revision Risk Differ for Primary Total Knee Arthroplasty Patients Who Have and Do not Have a Prior Primary or Revision Arthroplasty?

BACKGROUND: We sought to evaluate the risk of aseptic revision in total knee arthroplasty (TKA) patients who have and do not have a history of primary or revision arthroplasty of a different major joint. METHODS: We conducted a matched cohort study using data from Kaiser Permanente's arthroplasty registries. Patients who underwent primary unilateral TKA (index knee) were identified (2009-2018). Two matches based on exposure history were performed: (1) 33,714 TKAs with a history of primary arthroplasty of a different joint (contralateral knee, either hip, and/or either shoulder) were matched to 67,121 TKAs without an arthroplasty history and (2) 597 TKAs with a history of aseptic revision in a different joint were matched to 1,190 TKAs with a history of a prior arthroplasty in a different joint, but without any revision. After the matches were performed, Cox regressions were used to evaluate aseptic revision risk of the index knee using the no history groups as the reference in regression models. RESULTS: No difference in aseptic revision risk for the index knee was observed when comparing patients who had a prior primary arthroplasty in a different joint to those who did not have an arthroplasty history (hazard ratio = 0.95, 95% CI = 0.86-1.06). Those patients who did not have any prior aseptic revision history in a different joint had higher risk of aseptic revision in the index knee (hazard ratio = 2.06, 95% CI = 1.17-3.63). CONCLUSION: Patients who had a prior revision history had over a 2-fold higher risk of aseptic revision in the index knee, warranting close surveillance of these patients. LEVEL OF EVIDENCE: Level III.