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.

Risk of Revision and Reoperation After Quadriceps Tendon Autograft ACL Reconstruction Compared With Patellar Tendon and Hamstring Autografts in a US Cohort of 21,973 Patients

BACKGROUND

The use of quadriceps tendon (QT) autografts has increased in the past 10 years. However, there remains a dearth of large studies examining the effects of graft selection on anterior cruciate ligament reconstruction (ACLR) that includes QT grafts.

PURPOSE

To evaluate the risk of subsequent surgical outcomes, including revision and reoperation, for a large cohort of patients with primary ACLR according to autograft selection.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Data from a US health care system ACLR registry were used to conduct a cohort study. Primary isolated autograft ACLRs were identified (2012-2021). The exposure of interest was autograft type: QT, bone-patellar tendon-bone (BPTB), and hamstring tendon (HT). Multivariable Cox regression models were used to evaluate the risk of aseptic revision (defined as a subsequent surgery where removal and replacement of the original graft for noninfectious reasons was required) and risk of aseptic reoperation (defined as any subsequent surgery for noninfectious reasons where the graft was left intact) according to autograft selection.

RESULTS

The study sample comprised 21,973 ACLRs performed by 290 surgeons at 53 hospitals. QT, BPTB, and HT autografts were used in 1103 (5.0%), 9519 (43.3%), and 11,351 (51.7%) ACLRs, respectively. In adjusted models, no significant differences were observed in revision risk (hazard ratio [HR], 1.06; 95% CI, 0.60-1.89; P = .837) or reoperation risk (HR, 1.00; 95% CI, 0.70-1.43; P = .993) within 4 years of follow-up when comparing QT ACLR with BPTB ACLR. Additionally, no differences in 4-year revision (HR, 0.62; 95% CI, 0.34-1.12; P = .111) or reoperation (HR, 1.24; 95% CI, 0.85-1.80; P = .262) risks were observed when comparing QT ACLR with HT ACLR. HT ACLRs were noted to have a higher risk of revision (HR, 1.52; 95% CI, 1.25-1.84; P < .001) compared with BPTB ACLRs but a lower risk of reoperation (HR, 0.86; 95% CI, 0.75-0.98; P = .024).

CONCLUSION

In this large multicenter study using data from an ACLR registry, the authors found no difference in the risk of revision or reoperation when QT was compared with BPTB or HT autograft with the numbers available, but they did find a 1.5 times higher risk of revision when HT autograft was compared with BPTB autograft. Surgeons may use this information when choosing the appropriate graft for ACLR in their patients.

Female sex and ipsilateral reoperation risk following mesh-based inguinal hernia repair: a cohort study including 131,626 repairs in adults from an integrated healthcare system over a 10-year period

PURPOSE

We sought to compare females and males for the risk of reoperation following different inguinal hernia repair approaches (open, laparoscopic, and robotic).

METHODS

We conducted a retrospective cohort study including all patients aged ≥ 18 who underwent first inguinal hernia repair with mesh within a US integrated healthcare system (2010-2020). Data were obtained from the system's integrated electronic health record. Multiple Cox proportional-hazards regression was used to evaluate the association between sex and risk for ipsilateral reoperation during follow-up. Analysis was stratified by surgical approach (open, laparoscopic, and robotic).

RESULTS

The study cohort was comprised of 110,805 patients who underwent 131,626 inguinal hernia repairs with mesh, 10,079 (7.7%) repairs were in females. After adjustment for confounders, females had a higher risk of reoperation than males following open groin hernia repair (hazard ratio [HR] = 1.98, 95% CI 1.74-2.25), but a lower reoperation risk following laparoscopic repair (HR = 0.70, 95% CI 0.51-0.97). The crude 5-year cumulative reoperation probability following robotic repair was 2.8% in males and no reoperations were observed for females. Of females who had a reoperation, 10.3% (39/378) were for a femoral hernia, while only 0.6% (18/3110) were for femoral hernias in males.

CONCLUSION

In a large multi-center cohort of mesh-based inguinal hernia repair patients, we found a higher risk for reoperation in females after an open repair approach compared to males. Lower risk was observed for females through a minimally invasive approach (laparoscopic or robotic) and may be due to the ability to identify an occult femoral hernia through these approaches.

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.

Risk factors for reoperation following inguinal hernia repair: results from a cohort of patients from an integrated healthcare system

PURPOSE

Inguinal hernia repair is one of the most common operations performed globally. Identification of risk factors that contribute to hernia recurrence following an index inguinal hernia repair, especially those that are modifiable, is of paramount importance. Therefore, we sought to investigate risk factors for reoperation following index inguinal hernia repair.

METHODS

125,133 patients aged ≥ 18 years who underwent their first inguinal hernia repair with mesh within a large US integrated healthcare system were identified for a cohort study (2010-2020). Laparoscopic, robotic, and open procedures were included. The system's integrated electronic health record was used to obtain data on demographics, patient characteristics, surgical characteristics, and reoperations. The association of these characteristics with ipsilateral reoperation during follow-up was modeled using Cox proportional-hazards regression. Risk factors were selected into the final model by stepwise regression with Akaike Information Criteria, which quantifies the amount of information lost if a factor is left out of the model. Factors associated with reoperation with p < 0.05 were considered statistically significant.

RESULTS

The cumulative incidence of reoperation at 5-year follow-up was 2.4% (95% CI 2.3-2.5). Increasing age, female gender, increasing body mass index, White race, chronic pulmonary disease, diabetes, drug abuse, peripheral vascular disease, and bilateral procedures all associated with a higher risk for reoperation during follow-up.

CONCLUSION

This study identifies several risk factors associated with reoperation following inguinal hernia repair. These risk factors may serve as targets for optimization protocols prior to elective inguinal hernia repair, with the goal of reducing reoperation risk.

Direct Anterior Versus Posterior Approach for Total Hip Arthroplasty Performed for Displaced Femoral Neck Fractures

OBJECTIVES

To compare perioperative, 90-day, and 1-year postoperative complications and outcomes between the direct anterior approach (DAA) and the posterior approach for total hip arthroplasty in geriatric patients with displaced femoral neck fractures (FNFs).

DESIGN

Retrospective cohort study.

SETTING

Multicenter Health care Consortium.

PATIENTS

Seven-hundred and nine patients 60 years or older with acute displaced FNFs between 2009 and 2021.

INTERVENTION

Total hip arthroplasty using either DAA or posterior approach.

MAIN OUTCOME MEASUREMENTS

Rates of postoperative complications including dislocations, reoperations, and mortality at 90 days and 1 year postoperatively. Secondary outcome measures included ambulation capacity at discharge, ambulation distance with inpatient physical therapy, discharge disposition, and narcotic prescription quantities (morphine milligram equivalents).

RESULTS

Through a multivariable regression analysis, DAA was associated with significantly shorter operative time ( B = -6.89 minutes; 95% confidence interval [CI] -12.84 to -0.93; P = 0.024), lower likelihood of blood transfusion during the index hospital stay (adjusted odds ratios = 0.54; 95% CI 0.27 to 0.96; P = 0.045), and decreased average narcotic prescription amounts at 90 days (B = -230.45 morphine milligram equivalents; 95% CI -440.24 to -78.66; P = 0.035) postoperatively. There were no significant differences in medical complications, dislocations, reoperations, and mortality at 90 days and 1 year postoperatively.

CONCLUSION

When comparing the DAA versus posterior approach for total hip arthroplasty performed for displaced FNF, DAA was associated with shorter operative time, lower likelihood of blood transfusion, and lower 90-day postoperative narcotic prescription amounts.

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.

Mesh-based inguinal hernia repairs in an integrated healthcare system and surgeon and hospital volume: a cohort study of 110,808 patients from over a decade

PURPOSE

The aim of this study was to describe a cohort of patients who underwent inguinal hernia repair within a United States-based integrated healthcare system (IHS) and evaluate the risk for postoperative events by surgeon and hospital volume within each surgical approach, open, laparoscopic, and robotic.

METHODS

Patients aged ≥ 18 years who underwent their first inguinal hernia repair were identified for a cohort study (2010-2020). Average annual surgeon and hospital volume were broken into quartiles with the lowest volume quartile as the reference group. Multiple Cox regression evaluated risk for ipsilateral reoperation following repair by volume. All analyses were stratified by surgical approach (open, laparoscopic, and robotic).

RESULTS

110,808 patients underwent 131,629 inguinal hernia repairs during the study years; procedures were performed by 897 surgeons at 36 hospitals. Most repairs were open (65.4%), followed by laparoscopic (33.5%) and robotic (1.1%). Reoperation rates at 5 and 10 years of follow-up were 2.4% and 3.4%, respectively; rates were similar across surgical groups. In adjusted analysis, surgeons with higher laparoscopic volumes had a lower reoperation risk (27-46 average annual repairs: hazard ratio [HR] = 0.63, 95% confidence interval [CI] 0.53-0.74; ≥ 47 repairs: HR 0.53, 95% CI 0.44-0.64) compared to those in the lowest volume quartile (< 14 average annual repairs). No differences in reoperation rates were observed in reference to surgeon or hospital volume following open or robotic inguinal hernia repair.

CONCLUSION

High-volume surgeons may reduce reoperation risk following laparoscopic inguinal hernia repair. We hope to better identify additional risk factors for inguinal hernia repair complications and improve patient outcomes with future studies.

Similar rates of revision surgery following primary anatomic compared with reverse shoulder arthroplasty in patients aged 70 years or older with glenohumeral osteoarthritis: a cohort study of 3791 patients

BACKGROUND

Reverse total shoulder arthroplasty (RTSA), initially indicated for cuff tear arthropathy, is increasingly used to treat elderly patients with primary glenohumeral osteoarthritis (GHOA) and an intact rotator cuff. This is often done to avoid revision surgery in elderly patients for rotator cuff failure with anatomic total shoulder arthroplasty (TSA) despite traditionally good outcomes of TSA. We sought to determine whether there was a difference in outcomes in patients aged ≥70 years who received RTSA vs. TSA for GHOA.

METHODS

A retrospective cohort study was conducted using data from a US integrated health care system's shoulder arthroplasty registry. Patients aged ≥70 years who underwent primary shoulder arthroplasty for GHOA with an intact rotator cuff were included (2012-2021). RTSA was compared with TSA. Multivariable Cox proportional hazard regression was used to evaluate all-cause revision risk during follow-up, whereas multivariable logistic regression was used to evaluate 90-day emergency department (ED) visits and 90-day readmissions.

RESULTS

The final study sample comprised 685 RTSA patients and 3106 TSA patients. The mean age was 75.8 years (standard deviation, 4.6 years), and 43.4% of patients were men. After accounting for confounders, we observed no significant difference in all-cause revision risk for RTSA vs. TSA (hazard ratio, 0.79; 95% confidence interval [CI], 0.39-1.58). The most common reason for revision following RTSA was glenoid component loosening (40.0%). Over half of revisions following TSA were for rotator cuff tear (54.0%). No difference based on procedure type was observed in the likelihood of 90-day ED visits (odds ratio, 0.94; 95% CI, 0.71-1.26) and 90-day readmissions (odds ratio, 1.32; 95% CI, 0.83-2.09).

CONCLUSION

RTSA and TSA for GHOA with an intact rotator cuff in patients aged ≥70 years had a similar revision risk, as well as a similar likelihood of 90-day ED visits and readmissions. Although revision risk was similar, the most common causes of revision were different, with rotator cuff tears in TSA patients and glenoid component loosening in RTSA patients.

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.

Use of Preoperative CT Scans and Patient-Specific Instrumentation May Not Improve Short-Term Adverse Events After Shoulder Arthroplasty: Results from a Large Integrated Health-Care System

Ongoing innovation leads to a continuous influx of new technologies related to shoulder arthroplasty. These are made available to surgeons and marketed to both health-care providers and patients with the hope of improving outcomes. We sought to evaluate how preoperative planning technologies for shoulder arthroplasty affect outcomes.

Methods

This was a retrospective cohort study conducted using data from an integrated health-care system's shoulder arthroplasty registry. Adult patients who underwent primary elective anatomic or reverse total shoulder arthroplasty (2015 to 2020) were identified. Preoperative planning technologies were identified as (1) a computed tomography (CT) scan and (2) patient-specific instrumentation (PSI). Multivariable Cox regression and logistic regression were used to compare the risk of aseptic revision and 90-day adverse events, respectively, between procedures for which technologies were and were not used.

Results

The study sample included 8,117 procedures (in 7,372 patients) with an average follow-up of 2.9 years (maximum, 6 years). No reduction in the risk of aseptic revision was observed for patients having either preoperative CT scans (hazard ratio [HR] = 1.22; 95% confidence interval [CI] = 0.87 to 1.72) or PSI (HR = 1.44; 95% CI = 0.71 to 2.92). Patients having CT scans had a lower likelihood of 90-day emergency department visits (odds ratio [OR] = 0.84; 95% CI = 0.73 to 0.97) but a higher likelihood of 90-day venous thromboembolic events (OR = 1.79; 95% CI = 1.18 to 2.74). Patients with PSI use had a higher likelihood of 90-day deep infection (OR = 7.74; 95% CI = 1.11 to 53.94).

Conclusions

We found no reduction in the risk of aseptic revision with the use of these technologies. Patients having CT scans and PSI use had a higher likelihood of venous thromboembolism and deep infection, respectively. Ongoing research with extended follow-up is being conducted to further examine the effects of these technologies on patient outcomes.

Level of Evidence

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

No difference in revision risk between autologous hamstring graft less than 8 mm versus hybrid graft 8 mm or larger in anterior cruciate ligament reconstruction

PURPOSE

Hamstring autograft (HA) is commonly used for primary anterior cruciate ligament reconstruction (ACLR). However, if the harvested HA is inadequate in diameter, it is often augmented with an allograft tendon, forming a hybrid graft (HY). This study sought to evaluate aseptic revision risk following HA versus HY ACLR.

METHODS

A retrospective cohort study was performed using data obtained from our healthcare system's ACLR registry. Patients ≤ 25 years of age who underwent primary isolated ACLR were identified (2005-2020). Graft type and diameter size was the primary exposure of interest: < 8 mm HA and ≥ 8 mm HY. A secondary analysis was performed to examine 7 mm HA and 7.5 mm HA vs ≥ 8 mm HY. Propensity score-weighted Cox proportional hazard regression was used to evaluate the risk of aseptic revision.

RESULTS

The study sample included 1,945 ACLR: 548 ≥ 8 mm HY, 651 7 mm HA, and 672 7.5 mm HA. The crude cumulative aseptic revision probability at 8-years for ≥ 8 mm HY was 9.1%, 11.1% for 7 mm HA, and 11.2% for 7.5 mm HA. In adjusted analysis, no difference in revision risk was observed for < 8 mm HA (hazard ratio [HR] 1.15, 95% confidence interval [CI] 0.72-1.82), 7 mm HA (HR 1.23, 95% CI 0.71-2.11), or 7.5 mm HA (HR 1.16, 95% CI 0.74-1.82) compared to ≥ 8 mm HY.

CONCLUSION

In a US-based cohort of ACLR patients aged ≤ 25 years, we failed to observe any differences in aseptic revision risk for HA < 8 mm compared to HY ≥ 8 mm. Augmentation of a HA as small as 7 mm is not necessary to prevent a revision surgery.

LEVEL OF EVIDENCE

Level III.

Preoperative Patient Optimization: Outcomes from Elective Total Joint Arthroplasty in a Large US Healthcare System

INTRODUCTION

Patient factors are known to affect outcomes in arthroplasty surgery. A preoperative program to address modifiable factors may aid in more appropriate patient selection. We sought to assess patient selection and 90-day postoperative outcomes for total joint arthroplasty (TJA) candidates before and after implementation of a preoperative optimization protocol.

METHODS

A retrospective time-trend study using data from an integrated healthcare system's total joint replacement registry was done. The study sample consisted of patients aged 18 years or older who underwent primary elective total hip arthroplasty (THA) and total knee arthroplasty (TKA) for osteoarthritis between 2009 and 2019. Patients were divided into two cohorts: procedures performed from 2009 to 2013 ("preoptimization protocol") and those from 2015 to 2019 ("postoptimization protocol"); 2014 was excluded because an evidence-based preoperative patient optimization protocol was progressively implemented throughout the year. Patient characteristics, optimization factors, and 90-day outcomes (including emergency department [ED] visits, readmission, all-cause revision, deep infection, venous thromboembolism, and mortality) were compared between the two cohorts using the Pearson chi-square test or Wilcoxon test.

RESULTS

The study sample included 25,925 THA and 60,484 TKA. In the THA cohort, 10,364 (40.0%) and 15,561 (60.0%) were from the preoptimization and postoptimization cohorts, respectively. The postoptimization THA cohort saw lower rates of ED visits (12.1% vs. 9.4%, P < 0.001) and readmissions (5.6% vs. 3.8%, P < 0.001). In the TKA cohort, 24,054 (39.8%) and 36,430 (60.2%) were from the preoptimization and postoptimization cohorts, respectively. The postoptimization TKA cohort saw lower rates of ED visits (13.1% vs. 11.9%, P < 0.001), readmissions (5.6% vs. 3.0%, P < 0.001), all-cause revisions (0.5% vs. 0.3%, P = 0.003), venous thromboembolism (1.3% vs. 0.9%, P < 0.001), and mortality (0.3% vs. 0.2%, P = 0.011).

DISCUSSION

An evidence-based protocol to improve patient selection based on modifiable patient factors was adopted by orthopaedic surgeons in the system and utilization of the protocol before TJA was associated with fewer postoperative complications over time.

LEVEL OF EVIDENCE

Level IV.

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

OBJECTIVE

To evaluate the risk for 90-day returns to care and long-term subsequent surgical interventions following primary endovascular aneurysm repair (EVAR) with an Endologix AFX Endovascular AAA System compared to three other high-volume endograft devices.

METHODS

We conducted a matched cohort study using data from an integrated healthcare system's Endovascular Stent Graft Registry. Patients aged ≥18 years who underwent primary EVAR for AAA in the healthcare system from 1/1/2011-12/31/2017 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 healthcare 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 procedure characteristics. After the application of matching, conditional logistic regression was used to evaluate the likelihood for 90-day emergency department (ED) 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 to 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 more than 1-year following 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 use of AFX/AFX2.

CONCLUSION

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 to patients who received other high-volume devices. Patients who have received these devices should be closely monitored following EVAR.

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.

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.

Comparison of 90-Day Adverse Events Associated With Aspirin and Potent Anticoagulation Use for Venous Thromboembolism Prophylaxis: A Cohort Study of 72,288 Total Knee and 35,142 Total Hip Arthroplasty Patients

BACKGROUND

While aspirin is acceptable for venous thromboembolism (VTE) prophylaxis following total joint arthroplasty in most patients, more potent agents are used in patients considered higher risk for VTE. We evaluated the efficacy and safety of aspirin versus potent anticoagulation agents following total knee arthroplasty (TKA) and total hip arthroplasty (THA).

METHODS

A cohort study of 72,288 TKA and 35,142 THA from the Kaiser Permanente Total Joint Replacement Registry was performed (2009 to 2019). Identified medications were aspirin, factor Xa inhibitors, low-molecular-weight heparin (LMWH), and warfarin. A validated VTE risk score was assigned to each patient. Propensity score-weighted logistic regressions were used to evaluate 90-day VTEs. Noninferiority testing was performed with a margin of 1.25 using the upper bound (UB) of the 1-sided 95% CI.

RESULTS

For TKA, aspirin was not inferior to LMWH (odds ratio [OR] = 0.77, UB = 1.09) and warfarin (OR = 0.64, UB = 0.90); there was no evidence to support noninferiority of aspirin compared to factor Xa inhibitors. Findings were consistent for THA (LMWH: OR = 0.59, UB = 0.75; warfarin: OR = 0.69, UB = 0.89). TKA was considered higher risk for VTE, whereas aspirin use demonstrated noninferiority compared to warfarin (OR = 0.54, UB = 0.81), we lacked evidence of noninferiority when compared to LMWH and factor Xa inhibitors. We lacked evidence of noninferiority of aspirin versus any potent anticoagulation in higher-risk THA.

CONCLUSION

Aspirin was found to be effective and safe for VTE prevention in primary total joint arthroplasty, including in patients considered higher risk for VTE.

LEVEL OF EVIDENCE

III.

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.

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.

Procedure Cost Comparison of Outpatient and Inpatient Shoulder Arthroplasty and Lower-Extremity Arthroplasty Within a Managed-Care Organization

Introduction The authors sought to evaluate cost differences between shoulder arthroplasties and lower-extremity joint replacements in the outpatient and inpatient setting within a large health-maintenance organization. Methods A cross-sectional study of 100 total hip arthroplasties (THA), 100 total knee arthroplasties (TKA), and 100 shoulder arthroplasties (50 anatomical total shoulder arthroplasties and 50 reverse shoulder arthroplasties [RTSA]) was performed at a single regional health care center within an integrated health care maintenance organization. A time-driven activity-based costing methodology was used to obtain total cost of each episode for outpatient (vs) inpatient surgery. Results are presented by procedure type. Results Compared to their respective inpatient procedure, outpatient surgery was less expensive by 20% for RTSA, 22% for total shoulder arthroplasties, 29% for THA, and 30% for TKA. The cost of implants was the highest proportion of cost for all joint procedures across inpatient and outpatient settings, ranging from 28% of the total cost for inpatient THA to 63% of the cost for outpatient RTSA. Discussion Although many factors influence the total cost for arthroplasty surgery, including rate of hospitalization, duration of stay, operative time, complexity of cases, patient factors, equipment, and resource utilization, the implant cost remains the most expensive factor, with hospital bed admission status being the second costliest contribution. Conclusion Outpatient total arthroplasty substantially reduced procedure expenses in a managed-care setting by 20%-30%, although savings for outpatient shoulder arthroplasty was lower than savings for THA or TKA. Implant costs remain the largest portion of shoulder arthroplasty procedure expenses.

Acute and subacute anterior cruciate ligament reconstructions are associated with a higher risk of revision and reoperation

PURPOSE

(1) Report concomitant cartilage and meniscal injury at the time of anterior cruciate ligament reconstruction (ACLR), (2) evaluate the risk of aseptic revision ACLR during follow-up, and (3) evaluate the risk of aseptic ipsilateral reoperation during follow-up.

METHODS

Using a United States integrated healthcare system's ACLR registry, patients who underwent primary isolated ACLR were identified (2010-2018). Multivariable Cox proportional-hazards regression was used to evaluate the risk of aseptic revision, with a secondary outcome evaluating ipsilateral aseptic reoperation. Outcomes were evaluated by time from injury to ACLR: acute (< 3 weeks), subacute (3 weeks-3 months), delayed (3-9 months), and chronic (≥ 9 months).

RESULTS

The final sample included 270 acute (< 3 weeks), 5971 subacute (3 weeks-3 months), 5959 delayed (3-9 months), and 3595 chronic (≥ 9 months) ACLR. Medial meniscus [55.4% (1990/3595 chronic) vs 38.9% (105/270 acute)] and chondral injuries [40.0% (1437/3595 chronic) vs 24.8% (67/270 acute)] at the time of ACLR were more common in the chronic versus acute groups. The crude 6-year revision rate was 12.9% for acute ACLR, 7.0% for subacute, 5.1% for delayed, and 4.4% for chronic ACLR; reoperation rates a 6-year follow-up was 15.0% for acute ACLR, 9.6% for subacute, 6.4% for delayed, and 8.1% for chronic ACLR. After adjustment for covariates, acute and subacute ACLR had higher risks for aseptic revision (acute HR 1.70, 95% CI 1.07-2.72, p = 0.026; subacute HR 1.25, 95% CI 1.01-1.55, p = 0.040) and aseptic reoperation (acute HR 2.04, 95% CI 1.43-2.91, p < 0.001; subacute HR 1.31, 95% CI 1.11-1.54, p = 0.002) when compared to chronic ACLR.

CONCLUSIONS

In this cohort study, while more meniscal and chondral injuries were reported for ACLR performed ≥ 9 months after the date of injury, a lower risk of revision and reoperation was observed following chronic ACLR relative to patients undergoing surgery in acute or subacute fashions.

The association between critical shoulder angle and revision following anatomic total shoulder arthroplasty: a matched case-control study

HYPOTHESIS

The concept of the critical shoulder angle (CSA) was introduced in 2013, with studies showing that larger CSA is associated with rotator cuff tears (RCTs) and smaller CSA with glenohumeral osteoarthritis. We hypothesized outcomes following total shoulder arthroplasty (TSA) would differ depending on CSA.

METHODS

We conducted a matched case-control study using Kaiser Permanente's Shoulder Arthroplasty Registry to identify patients who underwent primary elective anatomic TSA for the diagnosis of osteoarthritis from 2009-2018. Seventy-eight adult patients who underwent revision following the primary TSA due to glenoid component failure or rotator cuff tear comprised the case group. A control group of nonrevised patients were identified from the same source population. Two controls were matched to each case by age, gender, body mass index, American Society of Anesthesiologists classification, surgeon who performed the index TSA, and post-TSA follow-up time. The relationship between revision and CSA as measured on radiographs were analyzed as a 1:2 matched-pairs case-control study with use of multiple conditional multivariable logistic regression.

RESULTS

Revised cases had a higher likelihood of a CSA ≥35° (odds ratio [OR] = 2.41, 95% confidence interval [CI] = 1.27-4.59). A higher likelihood of CSA ≥35° was observed for those revised for glenoid loosening (OR = 4.58, 95% CI = 1.20-17.50) and revised for rotator cuff tear (OR = 2.41, 95% CI = 1.18-4.92) compared with nonrevised controls. Every 5° increase in CSA had higher odds of overall revision (OR = 1.62, 95% CI = 1.18-2.21), glenoid loosening (OR = 2.50, 95% CI = 1.27-4.92), and rotator cuff tear (OR = 1.51, 95% CI = 1.07-2.14).

CONCLUSION

In a matched case-control study of primary anatomic TSA, individuals who were revised for aseptic glenoid loosening and superior cuff failure had a higher CSA compared with nonrevised individuals. These data suggest that surgeons may consider using reverse arthroplasty in cases of primary shoulder arthritis with a CSA of 35° or greater.

Association Between Anteromedial Portal Versus Tibial Tunnel Drilling and Meniscal Reoperation Risk Following Anterior Cruciate Ligament Reconstruction: A Cohort Study

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) provides functional stability to an injured knee. While multiple techniques can be used to drill the femoral tunnel during ACLR, a single technique has yet to be proven as clinically superior. One marker of postoperative functional stability is subsequent meniscal tears; a lower risk of subsequent meniscal surgery could be expected with improved knee stability.

PURPOSE

To determine if there is a meniscal protective effect when using an anteromedial portal (AMP) femoral tunnel drilling technique versus transtibial (TT) drilling.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

Data from Kaiser Permanente's ACLR registry were used to identify patients who had a primary isolated ACLR between 2009 and 2018; those with previous surgery in the index knee and meniscal pathology at the time of ACLR were excluded. The exposure of interest was TT (n = 2711) versus AMP (n = 5172) drilling. Multivariable Cox proportional hazard regression was used to evaluate the risk of a subsequent ipsilateral meniscal reoperation with adjustment for age, sex, femoral fixation, and graft choice. We observed a shift in surgeon practice from the TT to AMP over the study time frame; therefore, the relationship between technique and surgeon experience on meniscal reoperation was evaluated using an interaction term in the model.

RESULTS

At the 9-year follow-up, the crude cumulative meniscal reoperation probability for AMP procedures was 7.76%, while for TT it was 5.88%. After adjustment for covariates, we observed a higher risk for meniscal reoperation with AMP compared with TT (hazard ratio [HR], 1.53; 95% CI, 1.05-2.23). When stratifying by surgeon experience, this adverse association was observed for patients who had their procedure performed by surgeons with less AMP experience (no previous AMP ACLR: HR, 1.26; 95% CI, 0.84-1.91) while a protective association was observed for patients who had their procedure with more experienced surgeons (40 previous AMP ACLRs: HR, 0.34; 95% CI, 0.13-0.92).

CONCLUSION

Drilling the femoral tunnel via the AMP was associated with a higher risk of subsequent meniscal surgery compared with TT drilling. However, when AMP drilling was used by surgeons experienced with the technique, a meniscal protective effect was observed.

Risk of Revision After Hip Fracture Fixation Using DePuy Synthes Trochanteric Fixation Nail or Trochanteric Fixation Nail Advanced: A Cohort Study of 7,979 Patients

BACKGROUND

Prior reports of the DePuy Synthes Trochanteric Fixation Nail Advanced (TFNA) revealed a potential mode of fatigue failure at the proximal screw aperture following fixation of extracapsular hip fractures. We sought to compare the revision risk between the TFNA and its prior-generation forebear, the Trochanteric Fixation Nail (TFN).

METHODS

A retrospective cohort study was performed using data from a U.S. integrated health-care system's hip fracture registry. The study sample comprised patients who underwent cephalomedullary nail fixation for hip fracture with a TFN (n = 4,007) or TFNA (n = 3,972) from 2014 to 2019. We evaluated the charts and radiographs for patients who underwent any revision. Multivariable Cox regression was used to evaluate the risk of revision related to the index fracture.

RESULTS

At the 3-year follow-up, the cumulative probability of revision related to the index fracture was 1.8% for the TFN and 1.9% for the TFNA. After adjustment for covariates, no difference was observed in revision risk (hazard ratio [HR], 1.18 [95% confidence interval (CI), 0.80 to 1.75]; p = 0.40) for the TFNA compared with the TFN. The TFNA was associated with a higher risk of revision for nonunion than the TFN (HR, 1.86 [95% CI, 1.11 to 3.12]; p = 0.018). At the 3-year follow-up, implant breakage was 0.06% for the TFN and 0.2% for the TFNA; with regard to aperture failures related to the index fracture, there were 1 failure for the TFN group and 3 failures for the TFNA group.

CONCLUSIONS

In a large cohort from a U.S. hip fracture registry, the TFNA had an overall revision rate that was similar to that of the earlier TFN, with implant breakage being a rare revision reason for both groups. Chart and radiographic review found that the TFNA was associated with a higher risk of revision for nonunion.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Decreasing Trends in Reintervention and Readmission After Endovascular Aneurysm Repair in a Multiregional Implant Registry

OBJECTIVES

As endovascular aortic aneurysm repair (EVAR) matures into its third decade, measures such as long-term reintervention and readmission have become a focus of quality improvement efforts. Within a large United States integrated healthcare system, we describe time trends in the rates of long-term reinterventions utilization measures.

METHODS

Data from a US multiregional EVAR registry was used to perform a descriptive study of 3,891 adults who underwent conventional infrarenal EVAR for infrarenal abdominal aortic aneurysm between 2010 to 2019. Three-year follow-up was 96.7%. Outcomes included 1-, 3-, and 5-year graft revision (defined as a procedure involving placement of a new endograft component), secondary interventions (defined as a procedure necessary for maintenance of EVAR integrity, e.g., coil embolization and balloon angioplasty/stenting), conversion to open, interventions for type II endoleaks alone, and 90-day readmission. Crude cause-specific reintervention probabilities were calculated by operative year using the Aalen-Johansen estimator, with death as a competing risk and December 31, 2020 as the study end date.

RESULTS

Excluding interventions for type II endoleak alone, 1-year secondary intervention incidence decreased from 5.9% for EVARs in 2010 to 2.0% in 2019 (p<0.001) and 3-year incidence decreased from 7.2% to 3.6% from 2010 to 2017 (p=0.03). The 3-year incidences of graft revision (mean incidence 3.4%) and conversion to open remained fairly stable (mean incidence 0.6%) over time. The 3-year incidence of interventions for type II endoleak alone also decreased from 3.4% in 2010 to 0.7% in 2017 (p=0.01). 90-day readmission rates decreased from 19.3% for index EVAR in 2010 to 9.2% in 2019 (p=0.03).

CONCLUSIONS

Comprehensive data from a multiregional healthcare system demonstrates decreasing long-term secondary intervention and readmission rates over time in patients undergoing EVAR. These trends are not explained by evolving management of type II endoleaks and suggest improving graft durability, patient selection or surgical technique. Further study is needed to define implant and anatomic predictors of different types of long-term reintervention.

Radial head arthroplasty: a descriptive study of 970 patients in an integrated health care system

BACKGROUND

Radial head arthroplasty (RHA) is commonly performed for isolated comminuted radial head fractures and in conjunction with traumatic elbow instability. However, there is a paucity of literature directly describing the characteristics and outcomes of patients who undergo RHA in a community-based setting. We describe a cohort of 970 RHA performed in the California regions of a US integrated health care system over a 9-year period. Patient demographics, implant selection, 90-day acute postoperative events, and cumulative reoperation/revision rates are included.

METHODS

Patients aged ≥18 years who underwent primary RHA were identified (2009-2017). Patient characteristics and demographics, including age, body mass index, gender, diabetes status, American Society of Anesthesiologists (ASA) classification, primary diagnosis, and concomitant procedures were described. Crude cumulative revision and reoperation probabilities were calculated as 1 minus the Kaplan-Meier estimator, with follow-up time calculated as the time from the index RHA to revision/reoperation date for those with the outcome of interest and time from index RHA to censoring date (eg, date of death, health care termination, study end date [March 31, 2018]) for those without the outcome. Ninety-day postoperative incidence of emergency department (ED) visit, readmission, and mortality was calculated as the number of patients with the event of interest over the number of patients at risk.

RESULTS

A total of 970 patients underwent primary unilateral RHA by 205 surgeons during the study period. Annual procedure volume increased from 53 procedures in 2009 to 157 procedures in 2017. More patients were female, without diabetes, and had an ASA classification of 1 or 2. Fracture was the predominant indication for RHA (98.4%) and more than half (54.3%) had concomitant procedures performed. Most implants were press fit (63.2%) over loose fit, and >90% were monopolar. Three-year cumulative revision and reoperation probabilities following RHA were 6.5% (95% confidence interval [CI] = 5.0%-8.5%) and 8.2% (95% CI = 6.5%-10.3%), respectively. Revisions and reoperations tended to occur within the first postoperative year. Of the 970 RHA patients, 83 (8.5%) had a 90-day ED visit, 58 (6.0%) had a 90-day readmission, and 1 (0.1%) died within a 90-day postoperative period.

CONCLUSION

This large cohort of RHA patients provides information about the practice of RHA at large and in the community. Surgeons are performing more RHA over time and choosing press fit stems more often. Revisions and reoperations tended to occur early. Readmission and ED visits were low but not negligible, with pain being the most common reason for ED visit.

Revision Risk in a Cohort of US Patients Younger Than 55 Undergoing Primary Elective Total Hip Arthroplasty

BACKGROUND

As indications for elective total hip arthroplasty (THA) expand to younger patients, we sought to (1) compare revision risk following primary elective THA in patients <55 years at the time of their THA to patients aged ≥65 years and (2) identify specific risk factors for revision in patients <55 years.

METHODS

A Kaiser Permanente's total joint replacement registry was used to conduct a cohort study including primary elective THA patients aged ≥18 (2001-2018). In total, 11,671 patients <55 years and 53,106 patients ≥65 years were included. Multiple Cox regression was used to evaluate cause-specific revision risk, including septic revision, aseptic loosening, instability, and periprosthetic fracture. Stepwise Cox regression was used to identify patient and surgical factors associated with cause-specific revision in patients <55 years.

RESULTS

Patients <55 years had a higher risk of septic revision (hazard ratio [HR] = 1.30, 95% confidence interval [CI] = 1.02-1.66), aseptic loosening (HR = 2.60, 95% CI = 1.99-3.40), and instability (HR = 1.35, 95% CI = 1.09-1.68), but a lower risk of revision for periprosthetic fracture (HR = 0.36, 95% CI = 0.22-0.59) compared to patients aged ≥65 years. In the <55 age group, risk factors for septic revision included higher body mass index, drug abuse, and liver disease. Hypertension, anterior approach, and ceramic-on-ceramic were associated with aseptic loosening. White race, American Society of Anesthesiologists classification ≥3, smoker, paralysis, posterior approach, ceramic-on-ceramic, and smaller head diameter were associated with instability.

CONCLUSION

Identified risk factors varied depending on the cause for revision. Although septic revisions were related to patient characteristics, more modifiable factors, such as implant or surgical approach, were associated with revision due to aseptic loosening and instability.

LEVEL OF EVIDENCE

III.

Hip Fracture Surgery Volumes Among Individuals 65 Years and Older During the COVID-19 Pandemic

This study assesses hip fracture surgery volumes among older individuals in California during the pandemic compared with prepandemic rates.

Cause-Specific Stem Revision Risk in Primary Total Hip Arthroplasty Using Cemented vs Cementless Femoral Stem Fixation in a US Cohort

BACKGROUND

We sought to evaluate the cause-specific revision risk following hybrid (cemented stem mated to a cementless acetabular implant) vs cementless total hip arthroplasty (THA) in a US cohort.

METHODS

Primary elective THA for osteoarthritis was identified using Kaiser Permanente's Total Joint Replacement Registry (2001-2018). Multivariable Cox regression was used to evaluate cause-specific revision, including aseptic loosening, infection, instability, and periprosthetic fracture (PPF), for hybrid vs cementless THA. Analysis was stratified by age (<65, 65-74, and ≥75 years) and gender.

RESULTS

The study cohort comprised 88,830 THAs, including 4539 (5.1%) hybrid THAs. In stratified analysis, hybrid THA had a higher revision risk for loosening in females in all 3 age subgroups. A lower risk of revision for PPF was observed following hybrid THA in females aged ≥75 years. For females ≥75 years, cementless THA had an excess PPF risk of 0.9% while hybrid THA had an excess loosening risk of 0.2%, translating to a theoretical prevention of 10 PPF revisions but a price of 3 loosening revisions per 1000 hybrid THAs. No difference in revision risk was observed in males.

CONCLUSION

We observed differences in cause-specific revision risks by method of stem fixation which depended upon patient age and gender. Although the trend toward all cementless fixation continue, there may be a role for hybrid fixation in females ≥75 years to mitigate risk for revision due to PPF at the potential cost of a slight increase in longer term aseptic loosening.

LEVEL OF EVIDENCE

Level III.

Association Between Same-Day Discharge Total Joint Arthroplasty and Risk of 90-Day Adverse Events in Patients with ASA Classification of ≥3

BACKGROUND

Although safety in same-day discharge total joint arthroplasty (TJA) has been reported, findings are limited to healthier patients, specific surgeons, and/or specific institutions. Indications for same-day discharge TJA have expanded to include patients with multiple comorbidities; however, safety in this specific patient population remains unknown. Therefore, we sought to compare the risk of 90-day adverse events in higher-risk patients undergoing same-day discharge versus inpatient TJA.

METHODS

The Kaiser Permanente Total Joint Replacement Registry was utilized to conduct a cohort study. All patients with an American Society of Anesthesiologists (ASA) classification of ≥3 who underwent primary elective TJA for osteoarthritis from 2017 through 2018 were identified. The risk of 90-day adverse events (i.e., emergency department visits, unplanned readmissions, complications, and mortality) was evaluated with use of propensity score-weighted Cox proportional hazard regression including noninferiority testing with a margin of 1.10.

RESULTS

The cohort included a total of 5,250 patients who underwent total hip arthroplasty and 9,752 patients who underwent total knee arthroplasty, of whom 1,742 (33.2%) and 3,283 (33.7%) had same-day discharge, respectively. Same-day discharge hip arthroplasty was noninferior to an inpatient stay in terms of emergency department visits (hazard ratio [HR], 0.73; 1-sided HR 95% upper bound [UB], 0.84), readmissions (HR, 0.47; 95% UB, 0.61), and complications (HR, 0.63; 95% UB, 0.75); we did not have evidence of noninferiority for mortality (HR, 0.84; 95% UB, 1.97). Same-day discharge knee arthroplasty was noninferior to an inpatient stay in terms of emergency department visits (HR, 0.79; 95% UB, 0.87), readmission (HR, 0.80; 95% UB, 0.95), complications (HR, 0.72; 95% UB, 0.82), and mortality (HR, 0.53; 95% UB, 1.03).

CONCLUSIONS

We found that same-day discharge TJA did not increase the risk of emergency department visits, unplanned readmissions, and complications compared with an inpatient stay for higher-risk patients, suggesting that it is possible to expand indications for same-day discharge TJA in the hospital setting while maintaining safety.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Total Elbow Arthroplasty: A Descriptive Analysis of 170 Patients From a United States Integrated Health Care System

PURPOSE

Total elbow arthroplasty (TEA) can be used, with varying degrees of success, for the treatment of rheumatoid arthritis, osteoarthritis, and distal humerus fractures and their sequelae in elderly patients. Some of the largest studies of TEA have included data from more than 20 years ago and may not reflect the current practice of TEA. We sought to describe a modern cohort of patients who underwent TEA in a United States integrated health care system.

METHODS

All patients aged 18 years and older who underwent primary unilateral TEA from January 1, 2009, through March 31, 2018, were identified to conduct a descriptive study. The patients' characteristics and demographics, including age, body mass index, sex, diabetes status, American Society of Anesthesiologists classification, and surgical indication, were recorded. The crude cumulative revision probability as well as the 90-day postoperative incidence rate of emergency department visit, readmission, and mortality was calculated.

RESULTS

A total of 170 patients met our inclusion criteria. The annual procedure volume nearly doubled, from 11 procedures in 2009 to 21 procedures in 2017. The most common indication for TEA was fracture (40.6%), followed by rheumatoid arthritis (36.5%). At 4-year follow up, the crude cumulative revision probability was 9.8% (95% confidence interval, 5.6%-16.9%). Of the 170 patients who underwent TEA, 43 (25.3%) experienced a 90-day emergency department visit, 24 (14.1%) experienced a 90-day readmission, and 2 (1.2%) died within 90 days postoperatively.

CONCLUSIONS

This cohort of patients who underwent TEA using modern implants showed a notable increase in the volume of TEA over the study period, with more TEAs performed for trauma. The incidence of readmission and emergency department visits following TEA were high in this study. Further studies are needed to better define the current practice of TEA in the community at large.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Treatment of Intertrochanteric Femur Fractures with Long versus Short Cephalomedullary Nails

CONTEXT

Prior studies regarding indications for long vs short cephalomedullary nails in the treatment of intertrochanteric fractures had limited sample sizes and follow-up, suggesting a need for further investigation.

OBJECTIVE

To evaluate the association between cephalomedullary nail length and outcomes for the treatment of intertrochanteric femur fractures.

DESIGN

Cohort study using Kaiser Permanente's Hip Fracture Registry. A total of 5526 patients who underwent surgical treatment with cephalomedullary nails for an intertrochanteric femur fracture (2009-2014) were identified: 3108 (56.2%) with long nails and 2418 (43.8%) with short nails. Cox proportional hazards model regression was used to evaluate risks of all-cause revision and revision for periprosthetic fracture. Linear regression was used to evaluate operative time, estimated blood loss, and length of stay. Propensity score weights were used in all models to balance nail groups on patient and device characteristics.

MAIN OUTCOME MEASURES

All-cause revision surgery.

RESULTS

No association was found in risk of all-cause revision (hazard ratio = 0.75, 95% confidence interval [CI] = 0.48-1.15) or revision for periprosthetic fracture (hazard ratio = 0.59, 95% CI = 0.23-1.48) for long nails compared with short nails. Use of longer nails resulted in 18.80 more minutes of operative time (95% CI = 17.33-20.27 minutes), 41.10 mL more of estimated blood loss (95% CI = 31.71-50.48 mL), and a longer hospitalization (8.4 hours; β = 0.35, 95% CI = 0.12-0.58 hours).

CONCLUSION

These findings suggest that routine use of short cephalomedullary nails is safe and effective in the treatment of intertrochanteric fractures.

The Association Between Cement Viscosity and Revision Risk After Primary Total Knee Arthroplasty

BACKGROUND

Recent case series have reported early failure with the use of high-viscosity cement (HVC) in total knee arthroplasty (TKA). We evaluated revision risk after TKA with HVC compared with medium-viscosity cement (MVC) in a large cohort.

METHODS

We conducted a cohort study using data from Kaiser Permanente's Total Joint Replacement Registry. Patients who underwent fully cemented primary TKA for osteoarthritis were identified (2001-2018). Only posterior-stabilized, fixed-mobility designs of the 3 highest-volume implant systems (DePuy PFC, Zimmer NexGen, and Zimmer Persona) were included to mitigate confounding from implant characteristics. Palacos (Zimmer/Heraeus) and Simplex (Stryker) cements comprised the HVC and MVC exposure groups, respectively. Propensity score-weighted Cox proportional hazards regression was used to evaluate risk for any revision during follow-up and risk for revision from aseptic loosening specifically.

RESULTS

The final cohort comprised 76,052 TKAs, 41.1% using MVC. The crude 14-year cumulative revision probability was 4.55% and 5.12% for TKA with MVC and HVC, respectively. In propensity score-weighted Cox models, MVC compared with HVC had a lower risk of any revision (hazard ratio = 0.82, 95% confidence interval = 0.70-0.95) while no difference was observed for revision from aseptic loosening (hazard ratio = 0.80, 95% confidence interval = 0.56-1.13).

CONCLUSION

While we observed a lower risk for any revision with the use of Simplex MVC compared with Palacos HVC, we did not observe a difference in revision for aseptic loosening specifically. Given the widespread use of HVC, additional research to investigate other HVC and potential mechanisms for failure outside of loosening is warranted.

LEVEL OF EVIDENCE

Level III.

Postoperative opioid utilization associated with revision risk following primary shoulder arthroplasty

INTRODUCTION

With a substantial increase in utilization of primary shoulder arthroplasty, it is important to understand risk factors that may signal early failure and need for revision. Recent studies have reported that sustained postoperative opioid use is associated with a higher revision risk after total hip or knee arthroplasty. In this study, we evaluated postoperative opioid utilization as a risk factor for revision after primary shoulder arthroplasty.

METHODS

We conducted a cohort study using data from a United States integrated health care system's Shoulder Arthroplasty Registry. Patients who had a primary elective shoulder arthroplasty were identified (2009-2017); those with cancer or who underwent other arthroplasty procedures (either shoulder, hip, or knee) within the preceding year were excluded. Cumulative daily opioid utilization during the first year postoperative, calculated as oral morphine equivalents (OME), was categorized into 3 exposure groups: high user (≥15 mg OME daily), moderate user (<15 mg OME daily), and no opioid use (reference group). The exposure window was stratified into 2 time periods: postoperative days 1-90 and postoperative days 91-360. Multivariable Cox proportional-hazards regression was used to evaluate the association between postoperative opioid use and aseptic revision risk.

RESULTS

The final study sample included 8325 shoulder arthroplasty procedures. Of these individuals, 3707 (45%) received some opioid within the 1 year before the index procedure. We failed to observe a difference in aseptic revision risk between opioid utilization in the first 90 days postoperatively, regardless of dose. After the first 90 days, a higher revision risk was observed for high opioid users compared with nonusers (hazard ratio = 1.62, 95% confidence interval = 1.10-2.41), and no association was observed for moderate users (hazard ratio = 1.25, 95% confidence interval = 0.82-1.91).

CONCLUSIONS

We found a positive association between opioid consumption and aseptic revision risk after primary shoulder arthroplasty. This study cannot determine if opioids have a direct physiological cause that increases the risk of revision; rather it is likely that opioid consumption is a marker of chronic pain, poor function, and/or poor coping mechanisms. Further study is needed to determine if programs designed to decrease opioid use may impact revision risk after shoulder arthroplasty.

Modular Tibial Stem Use and Risk of Revision for Aseptic Loosening in Cemented Primary Total Knee Arthroplasty

BACKGROUND

Modular tibial stem extensions in total knee arthroplasty (TKA) are designed to reduce the risk of aseptic loosening of the tibial base plate. However, these implants add significant cost and an evaluation of their effectiveness in reducing this risk of loosening has not been studied in a large cohort. We sought to evaluate modular tibial stem utilization in primary TKA.

METHODS

We conducted a cohort study using our integrated healthcare system's Total Joint Replacement Registry. Patients who underwent cemented primary TKA were identified (2009-2019). Propensity scores were used to 1:1 match patients without to those with a stem extension. Cox proportional-hazards regression was used to evaluate the risk for revision due to aseptic loosening.

RESULTS

Ten thousand four hundred seventy six TKA with a modular tibial stem were matched to 10,476 TKA without a tibial stem. Stem utilization associated with a lower risk of revision for loosening across all postoperative follow-up (hazard ratio = 0.38, 95% confidence interval = 0.17-0.85).

CONCLUSION

In a matched cohort study, we observed presence of a stem extension was associated with a lower risk of revision for aseptic loosening. Further study to identify specific risk factors for aseptic loosening and confirm the findings presented here are warranted.

LEVEL OF EVIDENCE

Level III.

The association of multimorbidity to mortality in older adults after permanent pacemaker placement

BACKGROUND

In the United States 2018 bradycardia guideline, the current class III recommendation that patients with permanent pacemaker (PPM) indications and high multimorbidity burden may not have meaningful clinical benefit from PPM therapy is based on limited data.

METHODS

Observational study (January 1, 2008-December 31, 2015) of adults ≥65 years (N = 16,678) who underwent PPM implantation. Exposure variable: Elixhauser comorbidity number (ECN, 29 well-validated conditions).

PRIMARY OUTCOME

≤1-year mortality; secondary outcome: > 1-year mortality.

RESULTS

Those who died ≤1-year were older, had a lower body mass index (BMI), and higher ECN (p < .001). Cumulative survival at 1-year was 92.3% (95% confidence interval [CI]: 91.9-92.7). One-year survival decreased by increasing ECN-with a difference at 1-year between lowest and highest ECN category of 17.3% (ECN 0-1: 97.1% [95% CI: 96.3-97.7]; ECN ≥8: 79.8% [95% CI: 77.9-81.5]). For those who survived the first year, cumulative survival at 8-years was 51.2% (95% CI = 49.8-52.6) with a difference between ECN 0-1 and ≥8 of 43.4%. Increasing ECN was associated equally with ≤1-year (HR 1.28 [95% CI: 1.25-1.30]) and >1-year (HR 1.19 [95% CI: 1.17-1.20]) mortality. A predictive model including age, sex, BMI, PPM type, race, and ECN had greater discriminative ability (p < .0001) than a bedside model (age, sex) for the primary outcome.

CONCLUSION

Across the heterogeneity of indications for PPM placement, multimorbidity is increasingly common. The association of multimorbidity to mortality (≤1-year, >1-year) should be routinely discussed during the shared decision-making process as an important prognostic geriatric domain variable.

Variation and trends in reasons for knee replacement revision: a multi-registry study of revision burden

Background and purpose - Studies describing time-related change in reasons for knee replacement revision have been limited to single regions or institutions, commonly analyze only 1st revisions, and may not reflect true caseloads or findings from other areas. We used revision procedure data from 3 arthroplasty registries to determine trends and differences in knee replacement revision diagnoses.Patients and methods - We obtained aggregated data for 78,151 revision knee replacement procedures recorded by the Swedish Knee Arthroplasty Register (SKAR), the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), and the Kaiser Permanente Joint Replacement Registry (KPJRR) for the period 2003-2017. Equivalent diagnosis groups were created. We calculated the annual proportions of the most common reasons for revision.Results - Infection, loosening, and instability were among the 5 most common reasons for revision but magnitude and ranking varied between registries. Over time there were increases in proportions of revisions for infection and decreases in revisions for wear. There were inconsistent proportions and trends for the other reasons for revision. The incidence of revision for infection showed a uniform increase.Interpretation - Despite some differences in terminology, comparison of registry-recorded revision diagnoses is possible, but defining a single reason for revision is not always clear-cut. There were common increases in revision for infection and decreases in revision for wear, but variable changes in other categories. This may reflect regional practice differences and therefore generalizability of studies regarding reasons for revision is unwise.

Aseptic Revision and Reoperation Risks After Meniscectomy at the Time of Anterior Cruciate Ligament Reconstruction

BACKGROUND

An intact meniscus is considered a secondary stabilizer of the knee after anterior cruciate ligament reconstruction (ACLR). While loss of the meniscus can increase forces on the anterior cruciate ligament graft after reconstruction, it is unclear whether this increased loading affects the success of the graft after ACLR.

PURPOSE

To identify the risk of subsequent knee surgery when meniscectomy, either partial or total, is performed at the time of index ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

We conducted a matched cohort study using data from the Kaiser Permanente Anterior Cruciate Ligament Reconstruction Registry. Patients were identified who had a primary ACLR performed between January 1, 2005 and December 31, 2016, with up to 12 years of follow-up. The study sample comprised patients with ACLR who had a lateral meniscectomy (n = 2581), medial meniscectomy (n = 1802), or lateral and medial meniscectomies (n = 666). For each meniscectomy subgroup, patients with ACLR alone were matched to patients with a meniscectomy on a number of patient and procedure characteristics. After the application of matching, Cox proportional hazards regression was used to evaluate the risk of aseptic revision, while competing risks regression was used to evaluate the risk of cause-specific ipsilateral reoperation between meniscectomy and ACLR alone. Analysis was performed for each meniscectomy subgroup.

RESULTS

After the application of matching, we failed to observe a difference in aseptic revision risk for patients with ACLR and a meniscectomy-lateral (hazard ratio [HR], 0.80; 95% CI, 0.63-1.02), medial (HR, 0.95; 95% CI, 0.70-1.29), or both (HR, 1.25; 95% CI, 0.77-2.04)-as compared with ACLR alone. When compared with patients who had ACLR alone, patients with a lateral meniscectomy had a higher risk for subsequent lateral meniscectomy (HR, 1.89; 95% CI, 1.18-3.02; P = .008), and those with a medial meniscectomy had a lower risk for manipulation under anesthesia (HR, 0.13; 95% CI, 0.02-0.92; P = .041).

CONCLUSION

No difference in aseptic revision risk was observed for patients undergoing primary ACLR between groups with and without meniscectomy at the time of index surgery. Partial lateral meniscectomy at the time of index ACLR did associate with a higher risk of subsequent lateral meniscectomy.

Do PEEK Rods for Posterior Instrumented Fusion in the Lumbar Spine Reduce the Risk of Adjacent Segment Disease?

BACKGROUND

Polyetheretherketone (PEEK) rods were clinically introduced in the mid-2000s as an alternative to titanium (Ti) rods for posterior instrumented lumbar spine fusion, theorized to reduce the risk of adjacent segment disease (ASD). However, few studies have follow-up beyond 2 years. Consequently, we conducted a matched cohort study using data from Kaiser Permanente's spine registry to compare the 2 rod systems and risk for outcomes.

METHODS

Patients aged ≥18 undergoing first posterior lumbar fusion for a degenerative diagnosis from 2009 to 2018 using either a PEEK or a Ti rod were identified. Fusions using Ti rods were 2:1 propensity score matched to PEEK rods on the following factors: patient age, body mass index, smoking, American Society of Anesthesiologists classification, diagnosis, interbody use, bone morphogenic protein use, number of levels fused, fusion levels, and operative year. The matched sample included 154 PEEK and 308 Ti fusions. We used Cox regression to evaluate ASD and nonunion, and logistic regression to evaluate 90-day emergency department (ED) visit, readmission, and complication.

RESULTS

We did not observe a difference in risk for ASD (hazard ratio = 1.02, 95% confidence interval [CI] = 0.66-1.59) or ED visit (odds ratio [OR] = 0.88, 95% CI = 0.48-1.59). A lower likelihood of readmission (OR = 0.34, 95% CI = 0.13-0.94) was observed following PEEK fusion compared with Ti. No nonunions or 90-day complications were observed for the PEEK group; 5 (2-year cumulative incidence = 0.7%) nonunions and 4 (1.3%) complications were observed for the Ti group.

CONCLUSIONS

Our multicenter study did not support the hypothesis that PEEK rods are associated with a lower ASD risk. Reasons for readmission need to be identified to better understand the differences observed here. Further study of patients with TLIF using Ti and PEEK rods and posterolateral fusion with Ti and PEEK rods is needed.

CLINICAL RELEVANCE

The present study adds to the literature supporting their midterm effectiveness of PEEK rods compared with Ti rods for both their safety and their effectiveness at the 5-7-year follow-up.

LEVEL OF EVIDENCE

3.

The effect of a statewide COVID-19 shelter-in-place order on shoulder arthroplasty for proximal humerus fracture volume and length of stay

Background

Although the COVID-19 pandemic has disrupted elective shoulder arthroplasty throughput, traumatic shoulder arthroplasty procedures are less apt to be postponed. We sought to evaluate shoulder arthroplasty utilization for fracture during the COVID-19 pandemic and California's associated shelter-in-place order compared to historical controls.

Methods

We conducted a cohort study with historical controls, identifying patients who underwent shoulder arthroplasty for proximal humerus fracture in California using our integrated electronic health record. The time period of interest was following the implementation of the statewide shelter-in-place order: March 19, 2020-May 31, 2020. This was compared to three historical periods: January 1, 2020-March 18, 2020, March 18, 2019-May 31, 2019, and January 1, 2019-March 18, 2019. Procedure volume, patient characteristics, in-hospital length of stay, and 30-day events (emergency department visit, readmission, infection, pneumonia, and death) were reported. Changes over time were analyzed using linear regression adjusted for usual seasonal and yearly changes and age, sex, comorbidities, and postadmission factors.

Results

Surgical volume dropped from an average of 4.4, 5.2, and 2.6 surgeries per week in the historical time periods, respectively, to 2.4 surgeries per week after shelter-in-place. While no more than 30% of all shoulder arthroplasty procedures performed during any given week were for fracture during the historical time periods, arthroplasties performed for fracture was the overwhelming primary indication immediately after the shelter-in-place order. More patients were discharged the day of surgery (+33.2%, P = .019) after the shelter-in-place order, but we did not observe a change in any of the corresponding 30-day events.

Conclusions

The volume of shoulder arthroplasty for fracture dropped during the time of COVID-19. The reduction in volume could be due to less shoulder trauma due to shelter-in-place or a change in the indications for arthroplasty given the perceived higher risks associated with intubation and surgical care. We noted more patients undergoing shoulder arthroplasty for fracture were safely discharged on the day of surgery, suggesting this may be a safe practice that can be adopted moving forward.

Level of Evidence

Level III; Retrospective Case-control Comparative Study

Early revision in anatomic total shoulder arthroplasty in osteoarthritis: a cross-registry comparison

BACKGROUND

We evaluated anatomic total shoulders undergoing early revision (less than two years) in the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) and the Kaiser Permanente Shoulder Arthroplasty Registry (KPSAR).

METHODS

A cross-sectional comparison of both registries was performed between the years of 2009 and 2012. Only patients who underwent anatomic total shoulder arthroplasty for a primary diagnosis of osteoarthritis were included. Aggregate-level data of patients undergoing early revisions done within two years of index arthroplasty were evaluated, and descriptive analysis was conducted.

RESULTS

During the study period, 4614 patients were identified in the AOANJRR compared to 2036 in the KPSAR. Rotator cuff pathology, component loosening, and prosthetic instability were among the most common reasons for revision in both registries. A higher rate of revision in the AOANJRR was found to be secondary to the failure of one specific prosthesis, which has since been discontinued.

DISCUSSION

Comparing reasons for early revision in total shoulder arthroplasty revealed several similarities between the AOANJRR and KPSAR. Differences were also noted, and this study served to highlight the importance prosthesis selection can play in determining outcomes. Cooperation among registries may allow for earlier identification of risk factors for failure in shoulder arthroplasty.

Commercially Prepared Antibiotic-Loaded Bone Cement and Infection Risk Following Cemented Primary Total Knee Arthroplasty

BACKGROUND

The efficacy of commercially available antibiotic-loaded bone cement (ABC) in preventing infection in total knee arthroplasty (TKA) is unclear. We sought to determine the effectiveness of commercially available ABC in reducing the risk of infection following TKA, both overall and among 3 subgroups of patients with a higher risk of infection (diabetes, body mass index ≥35 kg/m, and American Society of Anesthesiologists classification ≥3), and to evaluate the association between the use of ABC and the risks of aseptic revision and revision for aseptic loosening.

METHODS

The Kaiser Permanente Total Joint Replacement Registry was utilized to evaluate 87,018 primary cemented TKAs performed from 2008 to 2016. The primary outcome was time to infection (90-day deep infection or septic revision). Reduced infection risk with ABC relative to regular cement was tested with use of propensity-score-weighted Cox proportional-hazards models with superiority and noninferiority testing. All analyses were replicated for each of the 3 high-risk subgroups. For the secondary revision outcomes, propensity-score-weighted Cox proportional-hazards models were utilized.

RESULTS

Regular cement was found to be noninferior to ABC with respect to risk infection (hazard ratio [HR], 1.14; 95% confidence interval [CI], 0.93 to 1.40) and cost across all TKA patients. However, a lower risk of infection was observed with ABC among TKA patients with diabetes (HR, 0.72; 95% CI, 0.52 to 0.99). There was no evidence of a difference in risk of revision for ABC compared with regular cement.

CONCLUSIONS

We found that the additional cost associated with the use of commercially prepared ABC in primary TKA was not justified in all patients; however, the risk of reduction was lower among patients with diabetes who received ABC. Further study is warranted to identify the efficacy of ABC among other high-risk populations.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

The association between glenoid component design and revision risk in anatomic total shoulder arthroplasty

INTRODUCTION

Anatomic total shoulder arthroplasty (TSA) is a proven treatment for glenohumeral joint osteoarthritis, with superior results compared with hemiarthroplasty. However, glenoid component loosening remains a problem and is one of the most common causes of failure in TSA. Multiple component designs have been developed in an attempt to reduce loosening rates. The purpose of this study was to evaluate risk of revision after anatomic TSA according to the glenoid component design.

METHODS

We conducted a cohort study including patients aged ≥18 years who underwent primary elective TSA for the diagnosis of osteoarthritis between 2010 and 2017. Patients with missing implant information, who received stemless humeral implants, or who received augmented glenoid implants, were excluded. Glenoid component designs used were categorized into 4 mutually exclusive treatment groups: polyethylene central-pegged ingrowth, polyethylene-metal hybrid, polyethylene all-cemented pegged, and polyethylene cemented keeled. Multivariable competing risk regression was used to evaluate the risk of glenoid loosening as a cause-specific revision by the glenoid component design.

RESULTS

Of the 5566 TSA included in the final cohort, 39.2% of glenoid implants were polyethylene central-pegged ingrowth, 31.1% were polyethylene-metal hybrid, 26.0% were polyethylene all-cemented pegged, and 3.6% were polyethylene cemented keeled. At 6-year final follow-up, 4.1% of TSA were revised for any cause, and 1.4% for glenoid loosening. Compared with the polyethylene central-pegged ingrowth design, no difference in glenoid loosening revision risk was observed for the polyethylene-metal hybrid design (hazard ratio [HR] = 1.15, 95% confidence interval [CI] = 0.42-3.20). However, both the polyethylene all-cemented pegged (HR = 2.48, 95% CI = 1.08-5.66) and polyethylene cemented keeled (HR = 3.84, 95% CI = 1.13-13.00) designs had higher risks for revision due to glenoid loosening.

CONCLUSIONS

We observed glenoid component designs to be associated with differential risks in revision due to glenoid loosening with polyethylene all-cemented pegged glenoids and polyethylene cemented keeled glenoids having higher risks when compared with polyethylene central-pegged ingrowth glenoids. Surgeons may want to consider the glenoid component design when performing anatomic TSA.

Does the use of preoperative bisphosphonates in patients with osteopenia and osteoporosis affect lumbar fusion rates? Analysis from a national spine registry

OBJECTIVE

Bisphosphonates are used to increase bone strength in treating osteopenia and osteoporosis, but their use for increasing lumbar fusion rates has been controversial. The objective of this study was to determine if preoperative treatment with bisphosphonates affects the reoperation rates for nonunions (operative nonunion rates) following lumbar fusions in patients with osteopenia or osteoporosis.

METHODS

The authors conducted a cohort study using data from the Kaiser Permanente Spine Registry. Patients (aged ≥ 50 years) with a diagnosis of osteopenia or osteoporosis who underwent primary elective lumbar fusions for degenerative disc disease, deformity, or spondylolisthesis were included in the cohort. Repeated spinal procedures at the index lumbar levels were noted through chart review. Reoperations for symptomatic nonunions (operative nonunions), time to nonunion, and the nonunion spine level(s) were also identified. The crude 2-year cumulative incidence of operative nonunions was calculated as 1 minus the Kaplan-Meier estimator. Cox proportional hazard regression was used to evaluate the association between preoperative bisphosphonate use and operative nonunion after adjustment for covariates. Analysis was stratified by osteopenia and osteoporosis diagnosis.

RESULTS

The cohort comprised 1040 primary elective lumbar fusion patients, 408 with osteopenia and 632 with osteoporosis. Ninety-seven (23.8%) patients with osteopenia and 370 (58.5%) patients with osteoporosis were preoperative bisphosphonate users. For the osteopenia group, no operative nonunions were observed in patients with preoperative bisphosphonate, while the crude 2-year incidence was 2.44% (95% CI 0.63–4.22) in the nonuser group. For the osteoporotic group, after adjustment for covariates, no difference was observed in risk for operative nonunions between the preoperative bisphosphonate users and nonusers (HR 0.96, 95% CI 0.20–4.55, p = 0.964).

CONCLUSIONS

To the authors’ knowledge, this study presents one of the largest series of patients with the diagnosis of osteopenia or osteoporosis in whom the effects of preoperative bisphosphonates on lumbar fusions were evaluated using operative nonunion rates as an outcome measure. The results indicate that preoperative bisphosphonate use had no effect on the operative nonunion rates for patients with osteoporosis. Similar indications were not confirmed in osteopenia patients because of the low nonunion frequency. Further studies are warranted to the determine if preoperative and postoperative timing of bisphosphonate use has any effect on lumbar fusion rates.