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.

Tranexamic acid is not associated with decreased infection risk after primary shoulder arthroplasty: a cohort study of 9276 patients.

BACKGROUND: The use of tranexamic acid (TXA) is associated with less blood loss and reduced transfusion risk after shoulder arthroplasty surgery. Recent studies have shown lower odds of postoperative infection after hip or knee arthroplasty with its use. The purpose of this study was to determine whether TXA use reduces the risk of infection after primary elective shoulder arthroplasty. METHODS: A retrospective cohort study was conducted using data from a US integrated health care system's shoulder arthroplasty registry. Patients aged 18 years who underwent primary elective anatomic total shoulder arthroplasty for osteoarthritis or primary reverse shoulder arthroplasty for rotator cuff arthropathy were included (2013-2020). We compared patients who received preoperative intravenous TXA to those who did not receive TXA by assessing the risk for revision due to deep infection within 5 years' follow-up using multivariable Cox proportional hazard regression. Interaction between TXA and diabetes status was analyzed separately. RESULTS: The study sample included 9276 shoulder arthroplasties performed by 153 surgeons at 43 hospitals. The mean age was 70.0 years and 48% were male. The 5-year probability of revision for deep infection was 0.8% and 0.7% for patients with and without TXA, respectively. We failed to observe a difference in infection risk after adjustment for confounders and surgeon differences (hazard ratio [HR] 1.00, 95% confidence interval [CI] 0.56-1.80, P = .998). Further, no differences were observed in patients with (HR 1.64, 95% CI 0.42-6.44, P = .481) or without diabetes (HR 0.79, 95% CI 0.40-1.55, P = .488). CONCLUSION: In a multicenter cohort of more than 9000 primary shoulder arthroplasty procedures, the use of preoperative TXA was not associated with a decrease in the 5-year probability of revision for deep infection.

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.

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.

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

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

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.

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.

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.

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.

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.

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.

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.

The association between race/ethnicity and outcomes following primary shoulder arthroplasty.

BACKGROUND: Although prior studies have reported health disparities in total knee and hip arthroplasty, few have evaluated the effect of race/ethnicity on total shoulder arthroplasty, particularly in a setting in which patients have uniform access to care. Because the procedural volume of shoulder arthroplasty has increased dramatically over the past decade, evaluating the association between race/ethnicity and postoperative outcomes is warranted. We sought to evaluate racial/ethnic disparities in adverse postoperative events within a universally insured shoulder arthroplasty cohort in an integrated health care system. METHODS: An integrated health care system's registry was used to identify patients who underwent elective primary (total or reverse) shoulder arthroplasty from 2005 to 2016. Four mutually exclusive race/ethnicity groups were investigated: white, Asian, black, and Hispanic. Racial differences were evaluated using Cox proportional hazards regression for all-cause revision and conditional logistic regression for 90-day unplanned readmissions and 90-day emergency department (ED) visits while adjusting for confounders. RESULTS: Of the 8360 shoulder procedures, 2% were performed in Asian patients; 5%, black patients; 9%, Hispanic patients; and 84%, white patients. Compared with white patients, Hispanic patients had a 44% lower revision risk (hazard ratio, 0.56; 95% confidence interval, 0.33-0.97). Black patients had a 45% higher likelihood of a 90-day ED visit (odds ratio, 1.45; 95% confidence interval, 1.12-1.89). CONCLUSION: We found minority groups to have revision and unplanned readmission risks that were similar to or lower than those of white patients. However, black patients had a higher likelihood of ED visits. Further investigation is needed to determine the reasons for this disparity and identify interventions to mitigate unnecessary ED visits.

Lower-extremity total joint arthroplasty in shoulder arthroplasty patients: does the order of the lower-extremity total joint arthroplasty matter?

BACKGROUND: As total joint arthroplasty (TJA) utilization increases, arthroplasties of multiple joints in a patient are more common. An understanding of the success of shoulder arthroplasty patients also requiring a lower-extremity (hip or knee) TJA is lacking. We evaluated the following questions: (1) Is there a difference in the revision risk following shoulder arthroplasty in patients who also undergo a lower-extremity TJA compared with those who do not? (2) Does the revision risk differ depending on the sequence of the procedures? METHODS: Patients who underwent elective primary shoulder arthroplasty from 2009 through 2015 were identified using Kaiser Permanente's shoulder arthroplasty registry. Patients with a lower-extremity TJA were identified using the institution's total joint replacement registry. Revision related to the index shoulder was modeled via Cox regression stratified by procedure type and adjusted for confounders. RESULTS: Of the 4751 shoulder arthroplasties identified, 1285 (27.0%) underwent a prior hip and/or knee arthroplasty and 483 (10.2%) underwent a hip and/or knee arthroplasty following the index shoulder arthroplasty. No difference was found in all-cause shoulder revision risk with lower-extremity TJA before (hazard ratio, 1.38; 95% confidence interval, 0.97-1.96) or after (hazard ratio, 1.30; 95% confidence interval, 0.82-2.06) the index shoulder arthroplasty compared with patients who underwent a shoulder arthroplasty only. CONCLUSION: In our study sample, we did not observe shoulder revision surgery risk to be different in patients who also underwent a lower-extremity TJA, regardless of the sequence of the 2 procedures. Future prospective studies should investigate whether the timing of the lower-extremity TJA in relation to the shoulder procedure impacts the latter's success.

Same-day discharge is not inferior to longer length of in-hospital stay for 90-day readmissions following shoulder arthroplasty.

BACKGROUND: Shoulder arthroplasty is a common orthopedic procedure, performed historically in the inpatient setting. However, interest in same-day discharge has increased. We sought to evaluate 90-day readmission, 90-day emergency department (ED) visit, 90-day deep infection, 90-day venous thromboembolism (VTE), and 1-year mortality after same-day shoulder arthroplasty compared with an inpatient stay. METHODS: We conducted a retrospective cohort study using data from an integrated health care system's Shoulder Arthroplasty Registry. A total of 6503 elective primary unilateral total shoulder and reverse total shoulder arthroplasties performed between 2005 and 2016 were included; 405 (6%) had same-day discharge. The likelihood of 90-day events, including readmission, ED visit, deep infection, and VTE, and 1-year mortality after same-day discharge was compared with 1- to 4-night inpatient stay using generalized estimating equations with noninferiority testing, adjusting for age, sex, body mass index, race, American Society of Anesthesiologists classification, select comorbidities, osteoarthritis, anesthesia type, procedure type, and surgeon effect. RESULTS: We failed to observe a difference between same-day discharge and 1- to 4-night stay in terms of 90-day readmission, 90-day ED visit, and 1-year mortality. Same-day discharge was not inferior to 1- to 4-night stay regarding 90-day readmission, but we did not have evidence to support noninferiority for 90-day ED visits or 1-year mortality. Ninety-day deep infections and VTE were too infrequent for adjusted analysis. CONCLUSIONS: We found same-day shoulder arthroplasty not to be inferior to an inpatient stay for 90-day readmission. Future investigation into the reasons for readmission and ED visit after same-day shoulder arthroplasty and interventions to mitigate these adverse events is needed.

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.

The Association of Race/Ethnicity and Total Knee Arthroplasty Outcomes in a Universally Insured Population.

BACKGROUND: Prior studies have documented racial/ethnic disparities in the United States for total knee arthroplasty (TKA) outcomes. One factor cited as a potential mediator is unequal access to care. We sought to assess whether racial/ethnic disparities persist in a universally insured TKA population. METHODS: A US integrated health system's total joint replacement registry was used to identify elective primary TKA (2000-2016). Racial/ethnic differences in revision and 90-day postoperative events (readmission, emergency department [ED] visit, infection, venous thromboembolism, and mortality) were analyzed using Cox proportional hazard and logistic regression with adjustment for confounders. RESULTS: Of 129,402 TKA, 68.8% were white, 16.2% were Hispanic, 8.4% were black, and 6.6% were Asian. Compared to white patients, Hispanic patients had lower risks of septic revision (hazard ratio [HR] = 0.69, 95% confidence interval [CI] = 0.57-0.83) and infection (odds ratio [OR] = 0.42, 95% CI = 0.30-0.59), but a higher likelihood of ED visit (OR = 1.28, 95% CI = 1.22-1.34). Black patients had higher risks of aseptic revision (HR = 1.61, 95% CI = 1.42-1.83), readmission (OR = 1.13, 95% CI = 1.02-1.24), and ED visit (OR = 1.31, 95% CI = 1.23-1.39). Asian patients had lower risks of aseptic revision (HR = 0.67, 95% CI = 0.54-0.83), septic revision (HR = 0.78, 95% CI = 0.60-0.99), readmission (OR = 0.89, 95% CI = 0.79-1.00), and venous thromboembolism (OR = 0.59, 95% CI = 0.45-0.78). CONCLUSION: We observed differences in TKA outcome, even within a universally insured population. While lower risks in some outcomes were observed for Asian and Hispanic patients, the higher risks of aseptic revision and readmission for black patients and ED visit for black and Hispanic patients warrant further research to determine reasons for these findings to mitigate disparities. LEVEL OF EVIDENCE: Level III.

Association Between Uncemented vs Cemented Hemiarthroplasty and Revision Surgery Among Patients With Hip Fracture.

IMPORTANCE: Consensus guidelines and systematic reviews have suggested that cemented fixation is more effective than uncemented fixation in hemiarthroplasty for displaced femoral neck fractures. Given that these recommendations are based on research performed outside the United States, it is uncertain whether these findings also reflect the US experience. OBJECTIVE: To compare the outcomes associated with cemented vs uncemented hemiarthroplasty in a large US integrated health care system. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study of 12 491 patients aged 60 years and older who underwent hemiarthroplasty treatment of a hip fracture between 2009 and 2017 at 1 of the 36 hospitals owned by Kaiser Permanente, a large US health maintenance organization. Patients were followed up until membership termination, death, or the study end date of December 31, 2017. EXPOSURES: Hemiarthroplasty (prosthetic replacement of the femoral head) fixation via bony growth into a porous-coated implant (uncemented) or with cement. MAIN OUTCOMES AND MEASURES: The primary outcome measure was aseptic revision, defined as any reoperation performed after the index procedure involving exchange of the existing implant for reasons other than infection. Secondary outcomes were mortality (in-hospital, postdischarge, and overall), 90-day medical complications, 90-day emergency department visits, and 90-day unplanned readmissions. RESULTS: Among 12 491 patients in the study cohort who underwent hemiarthroplasty for hip fracture (median age, 83 years; 8660 women [69.3%]), 6042 (48.4%) had undergone uncemented fixation and 6449 (51.6%) had undergone cemented fixation, and the median length of follow-up was 3.8 years. In the multivariable regression analysis controlling for confounders, uncemented fixation was associated with a significantly higher risk of aseptic revision (cumulative incidence at 1 year after operation, 3.0% vs 1.3%; absolute difference, 1.7% [95% CI, 1.1%-2.2%]; hazard ratio [HR], 1.77 [95% CI, 1.43-2.19]; P < .001). Of the 6 prespecified secondary end points, none showed a statistically significant difference between groups, including in-hospital mortality (1.7% for uncemented fixation vs 2.0% for cemented fixation; HR, 0.94 [95% CI, 0.73-1.21]; P = .61) and overall mortality (cumulative incidence at 1 year after operation: 20.0% for uncemented fixation vs 22.8% for cemented fixation; HR, 0.95 [95% CI, 0.90-1.01]; P = .08). CONCLUSIONS AND RELEVANCE: Among patients with hip fracture treated with hemiarthroplasty in a large US integrated health care system, uncemented fixation, compared with cemented fixation, was associated with a statistically significantly higher risk of aseptic revision. These findings suggest that US surgeons should consider cemented fixation in the hemiarthroplasty treatment of displaced femoral neck fractures in the absence of contraindications.

Survival and Reintervention Risk by Patient Age and Preoperative Abdominal Aortic Aneurysm Diameter after Endovascular Aneurysm Repair.

BACKGROUND: Endovascular aneurysm repair (EVAR) has become the standard of care for abdominal aortic aneurysm (AAA), but questions remain regarding the benefit in high-risk and elderly patients. The purpose of this study was to examine the effect of age, preoperative AAA diameter, and their interaction on survival and reintervention rates after EVAR. METHODS: Our integrated health system's AAA endograft registry was used to identify patients who underwent elective EVAR between 2010 and 2014. Of interest was the effect of patient age at the time of surgery (≤80 vs. >80 years old), preoperative AAA diameter (≤5.5 cm vs. >5.5 cm), and their interaction. Primary endpoints were all-cause mortality and reintervention. Between-within mixed-effects Cox models with propensity score weights were fit. RESULTS: Of 1,967 patients undergoing EVAR, unadjusted rates for survival at 4 years after EVAR was 76.1%, and reintervention-free rate was 86.0%. For mortality, there was insufficient evidence for an interaction between age and AAA size (P = 0.309). Patient age >80 years was associated with 2.53-fold higher mortality risk (hazard ratios [HR] = 2.53; 95% confidence intervals [CI], 1.73-3.70; P < 0.001), whereas AAA > 5.5 cm was associated with 1.75-fold higher mortality risk (HR = 1.75; 95% CI, 1.26-2.45; P = 0.001). For reintervention risk, there were no significant interactions or main effects for age or AAA diameter. CONCLUSIONS: Age and AAA diameter are independent predictors of reduced survival after EVAR, but the effect is not amplified when both are present. Age >80 years or AAA size >5.5 cm did not increase the risk of reintervention. No specific AAA size, patient age, or combination thereof was identified that would contraindicate AAA repair.

Diabetes Disease Severity Was Not Associated with Risk of Deep Infection or Revision After Shoulder Arthroplasty.

BACKGROUND: Prior studies have identified diabetes and disease severity (defined using hemoglobin A1c [HbA1c]) as potential risk factors for complications after shoulder arthroplasty. Evaluations of diabetes status and risk of adverse outcomes beyond the 30-day window either are limited or have not accounted for disease severity. Further, measures of diabetes severity other than HbA1c have yet to be investigated in a shoulder arthroplasty population. QUESTIONS/PURPOSES: (1) Are diabetes status and glycemic control associated with adverse events, including deep infection, all-cause revision, and 90-day readmission after shoulder arthroplasty? (2) Is postoperative HbA1c associated with revision risk? (3) Is there a threshold of preoperative HbA1c that best identifies patients with diabetes who are at higher risk of 3-year deep infection, 1-year all-cause revision, or 90-day readmission? (4) Can the Adapted Diabetes Complications Severity index (aDCSI) be used as an alternative measure of diabetes severity in evaluating the risk of deep infection, all-cause revision, and 90-day readmission and identification of patients with diabetes at higher risk for these events? (5) Is there a difference between elective and traumatic shoulder arthroplasty patients? METHODS: We conducted a retrospective registry-based cohort study using Kaiser Permanente's Shoulder Arthroplasty Registry (2005-2015). Primary shoulder arthroplasties were classified as patients with and without diabetes. Patients with diabetes were further evaluated using two disease severity measures (1) HbA1c, with good glycemic control classified as preoperative HbA1c < 7.0% and poor control defined as HbA1c ≥ 7.0%; and (2) aDCSI, classified as mild (score of 0-2) or severe (score ≥ 3) diabetes. Cox regression was used to evaluate the risk of deep infection and revision according to diabetes status and disease severity; conditional logistic regression was used for 90-day readmission. Time-dependent 1-year postoperative HbA1c was used to evaluate revision risk in Cox regression. All models were adjusted for covariates and stratified by elective versus trauma shoulder arthroplasty. Receiver operating characteristic curves were generated for HbA1c and aDCSI to determine whether a threshold exists to identify patients at higher risk of deep infection, all-cause revision, or 90-day readmission. The study sample consisted of 8819 patients; 7353 underwent elective shoulder arthroplasty and 1466 underwent shoulder arthroplasty due to trauma. For elective shoulder arthroplasty, 1430 patients (19%) had diabetes, and among the patients who underwent arthroplasty due to trauma, 444 (30%) had diabetes. RESULTS: Patients with diabetes who underwent elective shoulder arthroplasty and had poor glycemic control had a higher likelihood of 90-day readmission compared with patients without diabetes (OR, 1.5; 95% CI, 1.0-2.1; p = 0.032). No association was found for patients with diabetes who underwent shoulder arthroplasty due to trauma. No association was found between postoperative HbA1c and revision risk. Receiver operating characteristic curve analysis suggested preoperative HbA1c performed poorly at differentiating adverse events. When using aDCSI, patients with severe diabetes who underwent both elective and traumatic shoulder arthroplasty had a higher likelihood of 90-day readmission compared with patients without diabetes (OR, 1.6; 95% CI, 1.2-2.2; p = 0.001 and OR, 1.8; 95% CI, 1.2-2.7; p = 0.005, respectively). Similar to HbA1c, the aDCSI was a poor classifier in differentiating adverse events. CONCLUSIONS: Of the longer-term outcomes evaluated, more-severe diabetes was only found to be associated with an increase in 90-day readmissions after shoulder arthroplasty; a stronger association was found when using the aDCSI in identifying diabetes severity. Arbitrary cutoffs in HbA1c may not be the best method for determining risk of postoperative outcomes. Future work investigating perioperative diabetes management should work to identify and validate measures, such as the aDCSI, that better identify patients at higher risk for postoperative outcomes and, more importantly, whether outcomes can be improved by modifying these measures with targeted interventions. LEVEL OF EVIDENCE: Level III, therapeutic study.