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.

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

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

Temporal Trends in Deep Surgical Site Infections After Six Orthopaedic Procedures Over a 12-year Period Within a US-based Healthcare System.

INTRODUCTION: Centers of excellence and bundled payment models have driven perioperative optimization and surgical site infection (SSI) prevention with decolonization protocols and antibiotic prophylaxis strategies. We sought to evaluate time trends in the incidence of deep SSI and its causative organisms after six orthopaedic procedures in a US-based integrated healthcare system. METHODS: We conducted a population-level time-trend study using data from Kaiser Permanente's orthopaedic registries. All patients who underwent primary anterior cruciate ligament reconstruction (ACLR), total knee arthroplasty (TKA), elective total hip arthroplasty (THA), hip fracture repair, shoulder arthroplasty, and spine surgery were identified (2009 to 2020). The annual incidence of 90-day deep SSI was identified according to the National Healthcare Safety Network/Centers for Disease Control and Prevention guidelines with manual chart validation for identified infections. Poisson regression was used to evaluate annual trends in SSI incidence with surgical year as the exposure of interest. Annual trends in overall incidence and organism-specific incidence were considered. RESULTS: The final study sample was composed of 465,797 primary orthopaedic procedures. Over the 12-year study period, a decreasing trend in deep SSI was observed for ACLR and hip fracture repair. Although there was variation in incidence rates for specific operative years for TKA, elective THA, shoulder arthroplasty, and spine surgery, no consistent decreasing trends over time were found. Decreasing rates of Staphylococcus aureus infections over time after hip fracture repair, shoulder arthroplasty, and spine surgery and decreasing trends in antibiotic resistance after elective THA and spine surgery were also observed. Increasing trends of polymicrobial infections were observed after TKA and Cutibacterium acnes after elective THA. CONCLUSIONS: The overall incidence of deep SSI after six orthopaedic procedures was rare. Decreasing SSI rates were observed for ACLR and hip fracture repair within our US-based healthcare system. Polymicrobial infections after TKA and Cutibacterium acnes after elective THA warrant closer surveillance. LEVEL OF EVIDENCE: IV.

Association Between Race/Ethnicity and Total Joint Arthroplasty Utilization in a Universally Insured Population.

INTRODUCTION: Previous studies have documented racial and ethnic disparities in total joint arthroplasty (TJA) utilization in the United States. A potential mediator of healthcare disparities is unequal access to care, and studies have suggested that disparities may be ameliorated in systems of universal access. The purpose of this study was to assess whether racial/ethnic disparities in TJA utilization persist in a universally insured population of patients enrolled in a managed healthcare system. METHODS: This retrospective cohort study used data from a US integrated healthcare system (2015 to 2019). Patients aged 50 years and older with a diagnosis of hip or knee osteoarthritis were included. The outcome of interest was utilization of primary total hip arthroplasty and/or total knee arthroplasty, and the exposure of interest was race/ethnicity. Incidence rate ratios (IRRs) were modeled using multivariable Poisson regression controlling for confounders. RESULTS: There were 99,548 patients in the hip analysis and 290,324 in the knee analysis. Overall, 10.2% of the patients were Black, 20.5% were Hispanic, 9.6% were Asian, and 59.7% were White. In the multivariable analysis, utilization of primary total hip arthroplasty was significantly lower for all minority groups including Black (IRR, 0.55, 95% confidence interval [CI], 0.52-0.57, P < 0.0001), Hispanic (IRR, 0.63, 95% CI, 0.60-0.66, P < 0.0001), and Asian (IRR, 0.64, 95% CI, 0.61-0.68, P < 0.0001). Similarly, utilization of primary total knee arthroplasty was significantly lower for all minority groups including Black (IRR, 0.52, 95% CI, 0.49-0.54, P < 0.0001), Hispanic (IRR, 0.72, 95% CI, 0.70-0.75, P < 0.0001), and Asian (IRR, 0.60, 95% CI, 0.57-0.63, P < 0.0001) (all in comparison with White as reference). CONCLUSIONS: In this study of TJA utilization in a universally insured population of patients enrolled in a managed healthcare system, disparities on the basis of race and ethnicity persisted. Additional research is required to determine the reasons for this finding and to identify interventions which could ameliorate these disparities.

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.

Midterm outcomes for 605 patients receiving Endologix AFX or AFX2 Endovascular AAA Systems in an integrated healthcare system.

BACKGROUND: Endologix issued important safety updates for the AFX Endovascular AAA System in 2016 and 2018 owing to the risk of type III endoleaks. Outcomes with these devices are limited to small case series with short-term follow-up. We describe the midterm outcomes for a large cohort of patients who received an Endologix AFX or AFX2 device. STUDY DESIGN: Data from an integrated healthcare system's implant registry, which prospectively monitors all patients after endovascular aortic repair, was used for this descriptive study. Patients undergoing endovascular aortic repair with three AFX System variations (Strata [AFX-S], Duraply [AFX-D], and AFX2 with Duraply [AFX2]) were identified (2011-2017). Crude cumulative event probabilities for endoleak (types I and III), major reintervention, conversion to open, rupture, and mortality (aneurysm related and all cause) were estimated. RESULTS: Among 605 patients, 375 received AFX-S, 197 received AFX-D, and 33 received AFX2. Median follow-up for the cohort was 3.9 (interquartile range, 2.5-5.1) years. The crude 2-year incidence of overall endoleak, any subsequent reintervention or conversion, and mortality was 8.8% (95% confidence interval [CI], 6.3-12.3), 12.0% (95% CI, 9.1-15.9), and 8.8% (95% CI, 6.3-12.2) for AFX-S. Respective estimates for AFX-D were 7.9% (95% CI, 4.8-13.0), 10.6% (95% CI, 6.9-16.1), and 9.7% (95% CI, 6.3-14.7); for AFX2, they were 14.1% (95% CI, 4.7-38.2), 16.2% (95% CI, 6.4-37.7), and 21.2% (95% CI, 10.7-39.4). CONCLUSIONS: The midterm outcomes of a large U.S. patient cohort with an Endologix AFX or AFX2 System demonstrate a concerning rate of adverse postoperative events. Patients with these devices should receive close clinical surveillance to prevent device-related adverse events.

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.

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.

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.

Lumbar Spine Fusion Patients See Similar Improvements in Physical Activity Level to Non-Spine Fusion Patients Following Total Hip Arthroplasty.

BACKGROUND: The impact of prior lumbar spinal fusion on the change in physical activity level following total hip arthroplasty (THA) has not been thoroughly examined. Therefore, we sought to compare the change in physical activity level following THA for patients with and without a history of lumbar spine fusion. METHODS: Patients who underwent primary elective THA were identified using an integrated healthcare system's Total Joint Replacement Registry (2010-2013). Prior lumbar spine fusion was identified using the healthcare system's Spine Registry. Physical activity was self-reported by patients and measured in min/wk. Generalized linear models were used to evaluate the association between prior spine fusion and the change in physical activity from 1 year pre-THA to 1-2 years post-THA. RESULTS: Of 11,416 THAs, 90 (0.8%) had a history of lumbar spinal fusion. Patients with a prior lumbar fusion had a median physical activity level of 28 min/wk prior to THA compared to 45 min/wk in the patients with no history of lumbar spinal fusion. One year after THA, patients with a history of lumbar spinal fusion reported a median of 120 min/wk of physical activity compared to 150 min/wk for patients without a history of lumbar spinal fusion. The difference in physical activity level change between groups was not statistically significant (estimate = -23.1, 95% confidence interval -62.1 to 15.9, P = .246). CONCLUSION: Patients with prior lumbar fusion were found to have lower self-reported physical activity levels than patients without spine fusion both before and after THA surgery. However, both groups saw the same degree of improvement in physical activity level following THA. These findings may help in counseling patients who have had a prior lumbar spine fusion and in setting appropriate expectations prior to THA.

Association of Race and Ethnicity with Total Hip Arthroplasty Outcomes in a Universally Insured Population.

BACKGROUND: Prior studies have documented racial and ethnic disparities in total hip arthroplasty (THA) outcomes in the U.S. The purpose of this study was to assess whether racial/ethnic disparities in THA outcomes persist in a universally insured population of patients enrolled in an integrated health-care system. METHODS: A U.S. health-care system total joint replacement registry was used to identify patients who underwent elective primary THA between 2001 and 2016. Data on patient demographics, surgical procedures, implant characteristics, and outcomes were obtained from the registry. The outcomes analyzed were lifetime revision (all-cause, aseptic, and septic) and 90-day postoperative events (infection, venous thromboembolism, emergency department [ED] visits, readmission, and mortality). Racial/ethnic differences in outcomes were analyzed with use of multiple regression with adjustment for socioeconomic status and other potential confounders. RESULTS: Of 72,755 patients in the study, 79.1% were white, 8.2% were black, 8.5% were Hispanic, and 4.2% were Asian. Compared with white patients, lifetime all-cause revision was lower for black (adjusted hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.66 to 0.94; p = 0.007), Hispanic (adjusted HR, 0.73; 95% CI, 0.61 to 0.87; p = 0.002), and Asian (adjusted HR, 0.49; 95% CI, 0.37 to 0.66; p < 0.001) patients. Ninety-day ED visits were more common among black (adjusted odds ratio [OR], 1.15; 95% CI, 1.05 to 1.25; p = 0.002) and Hispanic patients (adjusted OR, 1.18; 95% CI, 1.08 to 1.28; p < 0.001). For all other postoperative events, minority patients had similar or lower rates compared with white patients. CONCLUSIONS: In contrast to prior research, we found that minority patients enrolled in a managed health-care system had rates of lifetime reoperation and 90-day postoperative events that were generally similar to or lower than those of white patients, findings that may be related to the equal access and/or standardized protocols associated with treatment in the managed care system. However, black and Hispanic patients still had higher rates of 90-day ED visits. Further research is required to determine the reasons for this finding and to identify interventions that could reduce unnecessary ED visits. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Association of Type and Frequency of Postsurgery Care with Revision Surgery after Total Joint Replacement.

CONTEXT: Postmarket surveillance is limited in the ability to detect medical device problems. Electronic health records can provide real-time information that might help with device surveillance. Specifically, the frequency of postsurgery care might indicate early problems and determine high-risk patients requiring more active surveillance. OBJECTIVE: To evaluate whether intensity of postsurgery care is associated with revision risk after total joint arthroplasty (TJA). DESIGN: Using an integrated health care system's TJA registry, we identified primary TJA performed between April 2001 and July 2013 (22,953 knees and 9904 hips). Survival analyses evaluated the frequency of specific types of outpatient and inpatient utilization 0 to 90 and 91 to 180 days postoperatively and revision risk. MAIN OUTCOME MEASURES: Revision surgery occurring at least 6 months after primary TJA. RESULTS: Knee arthroplasty recipients with 3 or more outpatient orthopedic allied health/nurse visits within 90 days had a 2.2 times (95% confidence interval [CI] = 1.6-2.9) higher risk of revision within the first 2 years postoperatively and 10.1 times higher risk (95% CI = 7.6-13.3) after 2 years. Compared with hip arthroplasty recipients who had 0 to 3 visits, patients with 6 or more outpatient orthopedic office visits within 90 days had a 15.7 times (95% CI = 5.7-42.9) higher risk of revision. Similar results were observed for 91-day to 180-day visits. CONCLUSION: Future studies are needed to determine if more specific data on reasons for the higher frequency of outpatient visits can refine these findings and elicit more specific recommendations for TJA devices.

Association Between Race and Ethnicity and Hip Fracture Outcomes in a Universally Insured Population.

BACKGROUND: Prior studies have documented racial and ethnic disparities in hip fracture treatment and outcome, and unequal access is commonly cited as a potential mediator. We sought to assess whether disparities in hip fracture outcome persist within a universally insured population of patients enrolled in a managed health-care system. METHODS: A U.S. integrated health systems registry was used to identify patients who underwent treatment for a hip fracture when they were ≥60 years of age from 2009 to 2014. Patient demographics, procedure details, and outcomes were obtained from the registry. Differences in outcome according to race/ethnicity were analyzed using multivariable regression analysis with adjustment for socioeconomic status and other potential confounders. RESULTS: Of 17,790 patients, 79.4% were white, 3.9% were black, 9.4% were Hispanic, and 7.4% were Asian. Compared with white patients, black patients had a similar 1-year mortality rate (odds ratio [OR] = 0.93, 95% confidence interval [CI] = 0.79 to 1.09, p = 0.37), Hispanic patients had a lower rate (OR = 0.85, 95% = CI = 0.75 to 0.96, p = 0.01), and Asian patients also had a lower rate (OR = 0.65, 95% CI = 0.56 to 0.76, p < 0.001). There were no differences in terms of surgical delay, 90-day emergency department visits, or reoperations during the patient's lifetime (p > 0.05) between the groups. Compared with white patients, black and Hispanic patients had fewer 90-day postoperative complications (p = 0.04 and p = 0.01, respectively); 90-day unplanned readmissions were less common among Asian patients (p = 0.03) but more common among black patients (p = 0.01). CONCLUSIONS: In this study of hip fractures treated in an integrated managed care system, minority patients were found to have postoperative mortality rates that were similar to, or lower than, those of white patients. These findings may be related to the equal access and/or standardized protocols associated with treatment in this managed care system. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Patient Factors Associated With Prolonged Postoperative Opioid Use After Total Knee Arthroplasty.

BACKGROUND: Pain persists in a moderate proportion of patients after total knee arthroplasty (TKA). Identifying patient factors that are associated with persistent pain may lead to improved care. PURPOSE: The purpose of the study was to identify preoperative factors associated with increased opioid prescriptions after TKA. METHODS: A retrospective cohort study of TKAs in an integrated health-care system (January 2008-December 2011) was conducted. The number of opioid prescriptions per 90-day period after TKA (up to 1 year), was the outcome of interest. Patient risk factors that were evaluated included demographics, pain prescriptions, comorbidities, and chronic pain conditions. Multivariable Poisson regression models were employed. RESULTS: The median age for 23,726 patients was 67 years. Before surgery, 60.0% used opioids. Three months after surgery, 41.2% of patients continued using opioids. Factors associated with greater opioid use included: younger age (odds ratio [OR] = 0.83, 95% confidence interval [CI] 0.82-0.84 per 10-year increase), liver disease (OR = 1.11, 95% CI 1.06-1.16), preoperative nonsteroidal anti-inflammatory drug use (OR = 1.09, 95% CI 1.07-1.10), anxiety (OR = 1.05, 95% CI 1.03-1.08), substance abuse (OR = 1.03, 95% CI 1.00-1.06), diabetes mellitus (OR = 1.03, 95% CI 1.01-1.05), preoperative opioid use (OR = 1.04, 95% CI 1.04-1.04), back pain (OR = 1.23, 95% CI 1.18-1.127), congestive heart failure (OR = 1.16, 95% CI 1.06-1.27), depression (OR = 1.14, 95% CI 1.09-1.18), fibromyalgia (OR = 1.10, 95% CI 1.02-1.18), hypertension (OR = 1.06, 95% CI 1.02-1.10), nonspecific chronic pain (OR = 1.06, 95% CI 1.02-1.10), black race (OR = 1.17, 95% CI 1.12-1.23), and chronic lung disease (OR = 1.05, 95% CI 1.01-1.10). CONCLUSION: Several preoperative factors were associated with prolonged opioid use after TKA, and their identification can assist providers guide pain management. Avoidance or weaning of preoperative opioids should be considered.

Reasons for Ninety-Day Emergency Visits and Readmissions After Elective Total Joint Arthroplasty: Results From a US Integrated Healthcare System.

BACKGROUND: Previous studies evaluating reasons for 30-day readmissions following total joint arthroplasty (TJA) may underestimate hospital-based utilization of healthcare resources during a patient's episode-of-care. We sought to identify common reasons for 90-day emergency department (ED) visits and hospital readmissions following primary elective unilateral TJA. METHODS: Patients from July 1, 2012 through June 30, 2015 having primary elective TJA and at least one 90-day postoperative ED-only visit and/or readmission for any reason were identified using the Kaiser Permanente Total Joint Replacement Registry. Chart reviews for ED visits/readmissions included 13 surgical and 11 medical reasons. The 2344 total hips and 5520 total knees were analyzed separately. RESULTS: Incidence of at least one ED visit following total hip arthroplasty (THA) was 13.4% and 4.5% for readmissions. The most frequent reasons for ED visits were swelling (15.6%) and pain (12.8%); the most frequent reasons for readmissions were infection (12.5%) and unrelated elective procedures (9.0%). The incidence of at least one ED visit following total knee arthroplasty (TKA) was 13.8%, and the incidence of readmission was 5.5%. The most frequent reasons for ED visits were pain (15.8%) and swelling (15.6%); the most common readmission reasons were gastrointestinal (19.1%) and manipulation under anesthesia (9.4%). CONCLUSION: Swelling and pain related to the procedure were the most frequent reasons for 90-day ED visits after both THA and TKA. Readmissions were most commonly due to infection or unrelated procedures for THA and gastrointestinal or manipulation under anesthesia for TKA. Modifications to discharge protocols may help prevent or alleviate these issues, avoiding unnecessary hospital returns.

Persistent Opioid Use Following Total Knee Arthroplasty: A Signal for Close Surveillance.

BACKGROUND: Prolonged opioid use following total knee arthroplasty (TKA) has not been extensively studied. METHODS: A cohort study of primary TKA for osteoarthritis using an integrated healthcare system and Total Joint Replacement Registry (January 2008-December 2011) was conducted. Opioid use during the first year after TKA was the exposure of interest and cumulative daily oral morphine equivalent (OME) amounts were calculated. Total postsurgical OME per 90-day exposure periods were categorized into quartiles. The end point was aseptic revision surgery. Survival analyses were conducted and hazard ratios (HRs) were adjusted for age, gender, prior analgesic use, opioid-related comorbidities, and chronic pain diagnoses. RESULTS: A total of 24,105 patients were studied. After the initial 90-day postoperative period, 41.5% (N = 9914) continued to use opioids. Also, 155 (0.6%) revisions occurred within 1 year and 377 (1.6%) within 5 years. Compared to patients not taking any opioids, patients using medium-low to high OME after the initial 90-day period had a higher adjusted risk of 1-year revision, ranging from HR = 2.4 (95% confidence interval, 1.3-4.5) to HR = 33 (95% confidence interval, 10-110) depending on the OME and time period. CONCLUSION: Patients who require opioids beyond 90 days after TKA warrant close follow-up.

Effect of body mass index on patient outcomes of surgical intervention for the lumbar spine.

BACKGROUND: Conflicting findings exist on the effect of obesity on outcomes of lumbar spine surgery; results depend on the diagnosis studied, procedure evaluated, definition of obesity, and specific outcomes measured. The purpose of this retrospective cohort study is to examine the effect of increasing body mass index (BMI) on surgical-related, health-related, and long-term outcomes of lumbar spine surgery in a single representative patient sample. METHODS: Using a surgical registry from an integrated health care system, 8,049 instrumented lumbar spine cases were identified between 1/1/2009 and 09/30/2013. The sample was stratified into five BMI categories. Outcomes of interest included: (I) surgical-related factors and complications; (II) health-related complications; and (III) long-term complications. Mixed linear models, conditional logistic regressions, and survival analysis using a Cox regression model were conducted controlling for surgeon effects. Age, gender, diabetes status, smoking status, admitting diagnosis, and surgical approach were included as covariates. RESULTS: Every 5 kg/m2 increase in BMI was associated with a significant increase in surgical time (7.8 minutes), estimated blood loss (EBL) (36.5 mL), risk of deep infection (OR =1.7 times), and deep vein thrombosis (DVT) (OR =1.5). BMI was not associated with increased incidence of other intraoperative or health-related complications. Rate of re-operation was 1.1 times higher with every 5 kg/m2 increase in BMI, but rate of re-operation due to adjacent segment disease (ASD) was not associated with BMI. CONCLUSIONS: Obesity had an adverse effect on certain surgical-related, health-related and long-term surgical outcomes. The magnitude of this effect increased with increasing levels of obesity, which increases the medical burden associated with obesity.

Effect of Surgeon and Hospital Volume on Morbidity and Mortality After Hip Fracture.

BACKGROUND: Prior studies have examined the relationship between surgeon and hospital volumes and outcome following hip fracture surgical procedures, but the results have been inconclusive. The purpose of this study was to assess the hip fracture volume-outcome relationship by analyzing data from a large, managed care registry. METHODS: The Kaiser Permanente Hip Fracture Registry prospectively records information on surgically treated hip fractures within the managed health-care system. Using this registry, all surgically treated hip fractures in patients 60 years of age or older were identified. Surgeon and hospital volume were defined as the number of hip fracture surgical procedures performed in the preceding 12 months and were divided into tertiles (low, medium, and high). The primary outcome was mortality at 1 year postoperatively. Secondary outcomes were mortality at 30 and 90 days postoperatively as well as reoperation (lifetime), medical complications (90-day), and unplanned readmission (30-day). To determine the relationship between volume and these outcome measures, multivariate logistic and Cox proportional hazards regression were performed, controlling for potentially confounding variables. RESULTS: Of 14,294 patients in the study sample, the majority were female (71%) and white (79%), and the mean age was 81 years. The overall mortality rate was 6% at 30 days, 11% at 90 days, and 21% at 1 year. We did not find an association between surgeon or hospital volume and mortality at 30 days, 90 days, or 1 year (p > 0.05). There was also no association between surgeon or hospital volume and reoperation, medical complications, or unplanned readmission (p > 0.05). CONCLUSIONS: In this analysis of hip fractures treated in a large integrated health-care system, the observed rates of mortality, reoperation, medical complications, and unplanned readmission did not differ by surgeon or hospital volume. In contrast to other orthopaedic procedures, such as total joint arthroplasty, our data do not suggest that hip fractures need to be preferentially directed toward high-volume surgeons or hospitals for treatment. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Mortality After Total Knee and Total Hip Arthroplasty in a Large Integrated Health Care System.

CONTEXT: The number of excess deaths associated with elective total joint arthroplasty in the US is not well understood. OBJECTIVE: To evaluate one-year postoperative mortality among patients with elective primary and revision arthroplasty procedures of the hip and knee. DESIGN: A retrospective analysis was conducted of hip and knee arthroplasties performed in 2010. Procedure type, procedure volume, patient age and sex, and mortality were obtained from an institutional total joint replacement registry. An integrated health care system population was the sampling frame for the study subjects and was the reference group for the study. MAIN OUTCOME MEASURES: Standardized 1-year mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated. RESULTS: A total of 10,163 primary total knee arthroplasties (TKAs), 4963 primary total hip arthroplasties (THAs), 606 revision TKAs, and 496 revision THAs were evaluated. Patients undergoing primary THA (SMR = 0.6, 95% CI = 0.4-0.7) and TKA (SMR = 0.4, 95% CI = 0.3-0.5) had lower odds of mortality than expected. Patients with revision TKA had higher-than-expected mortality odds (SMR = 1.8, 95% CI = 1.1-2.5), whereas patients with revision THA (SMR = 0.9, 95% CI = 0.4-1.5) did not have higher-than-expected odds of mortality. CONCLUSION: Understanding excess mortality after joint surgery allows clinicians to evaluate current practices and to determine whether certain groups are at higher-than-expected mortality risk after surgery.

Pediatric Hip Fractures in California: Results from a Community-Based Hip Fracture Registry.

CONTEXT: Hip fracture registries offer an opportunity to identify and to monitor patients with rare conditions and outcomes, including hip fractures in pediatric patients. OBJECTIVE: To report patient demographics and surgical outcomes of pediatric patients treated surgically for hip fractures in a large integrated health care system. DESIGN: Pediatric patients (< 21 years old at the time of fracture) with hip fractures were identified between 2009 and 2012 using our health care system's hip fracture registry. MAIN OUTCOME MEASURES: Patient characteristics, type of fracture, surgical treatment, and short-term complications. RESULTS: Among 39 patients identified, 31 (79.5%) were male, and the median age was 15 years old (interquartile range: 11-17 years). Most patients were Hispanic (n = 17, 43.6%) or white (n = 14, 35.9%). There were 8 patients (20.5%) with 15 comorbidities. Delbet Type IV (intertrochanteric) fractures were the most common fracture type (n = 22, 56.4%), and fixation method was equally distributed between intramedullary, screw and sideplate, and screws (n = 12, 30.8% for each). Most surgeries were performed by medium-volume surgeons (n = 22, 56.4%) at medium- and high-volume hospitals (n = 37, 94.9%). Three 90-day readmissions (7.7%), 1 infection (2.6%), 1 malunion (2.6%), and 1 revision (2.6%) were observed in this cohort during the study period. CONCLUSION: In our series using registry data, hip fractures younger than age 21 years were more common in boys and Hispanic patients. Intertrochanteric fractures (Delbet Type IV) were the most frequently observed type in our community-based hip fracture registry. Short-term complications were infrequent.