Introduction. Total Hip Arthroplasty has been shown to have excellent long term outcomes, yet early reoperation remains a risk. The current study assesses the incidence, causes, and cost associated with early revision following elective primary THA in the US Medicare population. Methods. The study used the Limited Data Set (LDS) from the Centers for Medicate and Medicaid Services (CMS) to identify all primary THA (DRG 469/470) performed in the US (excluding Maryland) during 2016. All cases were followed for one year after the original date of operation to create a database of readmissions after surgery. These data allowed for the determination of the 1-year incidence and type of reoperation, the timing of reoperation, the admitting diagnosis, hospital utilization, and total cost. Results. There were 164,050 THA performed on Medicare patients in the US in 2016. After surgery, there were 24,728 associated readmissions during the 1-year follow-up, or a readmission rate of 15.1%. There were 5,646 readmissions with a procedure performed on the hip; this represents 23% of the total 1-year readmissions after surgery, or a reoperation rate of 3.4%. Admission for reoperation was the most common reason for readmission following elective primary THA. When looking at reoperations, fracture was the most common (41.69%). 45% of reoperations occur within the first 30 days, 74% of reoperations occur within the first 90 days, and 26% of reoperations occur between days 90 and 360. For reoperations, a primary diagnosis of infection was associated with the highest average total cost ($104,024). Conclusions. Revision after THA is both a frequent occurance and expensive one. Fractures are the most common diagnoses that lead to revision, followed by dislocation. Increased focus to reduce complications such as fracture and dislocation would have the most beneficial impact on the patient, as well as on the healthcare system. For any tables or figures, please contact the authors directly

Aims. This work aimed at answering the following research questions: 1) What is the rate of mechanical complications, nonunion and infection for head/neck femoral fractures, intertrochanteric fractures, and subtrochanteric fractures in the elderly USA population? and 2) Which factors influence adverse outcomes?. Methods. Proximal femoral fractures occurred between 1 January 2009 and 31 December 2019 were identified from the Medicare Physician Service Records Data Base. The Kaplan-Meier method with Fine and Gray sub-distribution adaptation was used to determine rates for nonunion, infection, and mechanical complications. Semiparametric Cox regression model was applied incorporating 23 measures as covariates to identify risk factors. Results. Union failure occured in 0.89% (95% confidence interval (CI) 0.83 to 0.95) after head/neck fracturs, in 0.92% (95% CI 0.84 to 1.01) after intertrochanteric fracture and in 1.99% (95% CI 1.69 to 2.33) after subtrochanteric fractures within 24 months. A fracture-related infection was more likely to occur after subtrochanteric fractures than after head/neck fractures (1.64% vs 1.59%, hazard ratio (HR) 1.01 (95% CI 0.87 to 1.17); p < 0.001) as well as after intertrochanteric fractures (1.64% vs 1.13%, HR 1.31 (95% CI 1.12 to 1.52); p < 0.001). Anticoagulant use, cerebrovascular disease, a concomitant fracture, diabetes mellitus, hypertension, obesity, open fracture, and rheumatoid disease was identified as risk factors. Mechanical complications after 24 months were most common after head/neck fractures with 3.52% (95% CI 3.41 to 3.64; currently at risk: 48,282). Conclusion. The determination of complication rates for each fracture type can be useful for informed patient-clinician communication. Risk factors for complications could be identified for distinct proximal femur fractures in elderly patients, which are accessible for therapeutical treatment in the management. Cite this article: Bone Jt Open 2023;4(10):801–807

Aims. Cephalomedullary nails (CMNs) are commonly used for the treatment of intertrochanteric hip fractures. Total hip arthroplasty (THA) may be used as a salvage procedure when fixation fails in these patients. The aim of this study was to analyze the complications of THA following failed intertrochanteric hip fracture fixation using a CMN. Patients and Methods. Patients who underwent THA were identified from the 5% subset of Medicare Parts A/B between 2002 and 2015. A subgroup involving those with an intertrochanteric fracture that was treated using a CMN during the previous five years was identified and compared with the remaining patients who underwent THA. The length of stay (LOS) was compared using both univariate and multivariate analysis. The incidence of infection, dislocation, revision, and re-admission was compared between the two groups, using multivariate analysis adjusted for demographic, hospital, and clinical factors. Results. The Medicare data yielded 56 522 patients who underwent primary THA, of whom 369 had previously been treated with a CMN. The percentage of THAs that were undertaken between 2002 and 2005 in patients who had previously been treated with a CMN (0.346%) more than doubled between 2012 and 2015 (0.781%). The CMN group tended to be older and female, and to have a higher Charlson Comorbidity Index and lower socioeconomic status. The mean LOS was 1.5 days longer (5.3 vs 3.8) in the CMN group (p < 0.0001). The incidence of complications was significantly higher in the CMN group compared with the non-CMN group: infection (6.2% vs 2.6%), dislocation (8.1% vs 4.5%), revision (8.4% vs 4.3%), revision for infection (1.1% vs 0.37%), and revision for dislocation (2.2% vs 0.6%). Conclusion. The incidence of conversion to THA following failed intertrochanteric hip fracture fixation using a CMN continues to increase. This occurs in elderly patients with increased comorbidities. There is a significantly increased risk of infection, dislocation, and LOS in these patients. Patients with failed intertrochanteric hip fracture fixation using a CMN who require THA should be made aware of the increased risk of complications, and steps need to be taken to reduce this risk. Cite this article: Bone Joint J 2019;101-B(6 Supple B):91–96

Introduction. Patient demand for hip and knee arthroplasty continues to rise. Information sources providing data on the volume and cost of Medicare total joint arthroplasty by hospital are of use to patients and healthcare professionals. Data have demonstrated that higher volume surgeons are associated with lower cost, morbidity, and mortality. The current study assesses if the same is true for hospitals. Methods. The Limited Data Set (LDS) from the Centers for Medicare and Medicaid (CMS) were used for this study. All elective, DRG 470 Total Hip Arthroplasties (THA) reported by CMS from the first quarter of 2013 through the second quarter of 2016 were included. Volume and part A Medicare payments over a 90-day period for the 20 highest volume hospitals in the US were analyzed. Cost associated with initial hospital stay and post discharge skilled nursing, home health, long term acute care, inpatient rehabilitation facilities, and readmission was aggregated and analyzed. For each episode, demographic information (age, sex, and race), geographic location, and Elixhauser comorbidities were calculated to control for major confounding factors in the regression. Results. For the 20 highest volume centers in the US, total joint volume for CMS insured patients varied from 1104 to 5069. Average cost varied from $16,974 to $22,094. For the 20 highest volume cities in the US, total joint volume for CMS insured patients varied from 1,501 to 6,727. Average Medicare part A payment varied from $14,255 to $21,125. Readmission % varied from 3.9% to 8.2%. 90-day mortality varied from 0.0% to 0.57%. DISCUSSION AND CONCLUSION. The variation in volume between the top 20 centers in the US varies by more than a factor of 4 with the highest volume hospital having almost twice the volume as the second highest hospital. Part A payments, readmissions, and mortality also varied widely. Within the top 20 hospitals by volume, there does not appear to be a correlation between volume and cost

Introduction. Alternative payment models for total hip arthroplasty (THA) were initiated by the Center for Medicare and Medicaid Services (CMS) to decrease overall healthcare cost by optimizing healthcare delivery. The associated shift of financial risk to participating institutions has been criticized to introduce patient selection in order to avoid potentially high cost of care. This study aimed to evaluate the impact of the Comprehensive Care for Joint Replacement (CJR) model on patient selection, care delivery and hospital costs at a single care center. Methods. This is a retrospective review of THA patient from July 2015-December 2017 was performed. Patient were stratified by insurance type (Medicare and commercial insurance) and whether care was provided before or after implementation of the CJR bundle. Patient age, gender, and BMI, as well as Elixhauser comorbidities and ASA scores were analyzed. Delivery of care variables including surgery duration, discharge disposition, length of stay, and direct hospital costs were compared before and after CJR implementation. Results. 751 THA patients (273 Medicare and 478 Commercial Insurance) were evaluated before (29%) and after (71%) CJR bundle implementation. There was no difference in patient demographics (age, gender, or BMI); however, commercially insured patients had less Elxihauser comorbidies pre-bundle (p=0.033). After CJR implementation length of stay (p=0.010) for Medicare patients was reduced with a trend toward discharge to home (p=0.019). However, surgical time and OR service time as well as direct hospital costs were similar before and after the CJR bundle initiation. Conclusions. There was no differential patient selection after CJR bundle implementation, and value-based metrics (surgical time, OR service time) were not affected. Patients were discharged sooner and more often to home. However, overall direct hospital expenses remained unchanged revealing that any cost savings were for insurance providers, not participating hospitals. For any tables or figures, please contact the authors directly

Introduction. Quality measures play a substantial role in the Centers for Medicare and Medicaid Services' hospital payment and public reporting programs. The purpose of this study was to assess whether public measurement of total hip and knee arthroplasty risk-standardized readmission (RSRRs) and complication rates (RSCRs) was temporally associated with decreasing rates of adverse outcomes among Medicare beneficiaries. Methods. We evaluated annual trends in hospital-level risk-standardized complication and readmission rates in the fiscal years 2010–11 and 2016–17 for patients undergoing hospital-based inpatient hip/knee replacement procedures. We calculated hospital-level rates using the same measures and methodology used in public reporting. We examined annual trends in the distribution of hospital-level outcomes through density plots (similar to histograms). Results. Both rates of and variation in the complication and readmission outcomes declined steadily between 2010–11 and 2016–17. We noted a 33% relative reduction in hospital-level risk-standardized complication rates (RSCRs) and 25% relative reduction in hospital-level risk-standardized readmission rates (RSRRs). The interquartile range of RSCRs decreased by 18% (relative reduction) and of RSRRs decreased by 34% (relative reduction). Risk variable frequency in complication and readmission models did not systematically change over time, suggesting no evidence of widespread bias or up-coding. Conclusion. This study demonstrates that hospital-level complication and readmission rates after hip/knee replacements and variation in hospital-level performance declined following the start of public reporting and financial incentives associated with measurement. The consistent decreasing trend in rates of and variation outcomes suggests steady improvements and greater consistency among hospitals in clinical outcomes for hip/knee replacement patients in the years 2016–17 compared to 2010–11. While improvements in surgical practices and care coordination may partially account for these findings, the precise influence of measure public reporting on clinical outcomes is difficult to ascertain. Interactions between public reporting, payment, and hospital coding practices are complex and require continued study

Background. The Comprehensive Care for Joint Replacement (CJR) model was implemented in April-2016 to standardize cost and improve quality of care for two of the most commonly billed inpatient procedures for Medicare patients, total knee and total hip arthroplasty. The purpose of this study is to compare one institution's predicted savings and losses under the CJR model with actual savings and losses after two years of implementation and discuss new methods to maintain savings. Methods. Using our institution's data, we calculated the mean cost per episode of care. We calculated the percent reduction in target price and percent savings or losses per case for the CJR and Bundle Payment Care Initiative (BPCI) for each Medicare Severity Diagnosis Related Group (MS-DRG) using mean cost per episode and CJR and BPCI target prices. We compared the target prices, annual savings, and losses per episode of care for both CJR and BPCI. All CJR savings, projected and actual, were computed by comparing CJR savings to that of 2018 BPCI savings. Results. We found an average savings of 2.32% under CJR compared to the projected loss of −11.6% for MS-DRG 469 with fracture. There was a 7.97% savings for MS-DRG 470 without fracture compared to the projected 1.9%, a 20.94% savings for MS-DRG 470 with fracture compared to the projected 23.7%, and a loss of −3.98% for MS-DRG 469 without fracture compared to the projected 2.5% savings. Conclusions. The CJR target prices are lower than that of BPCI and this makes maintaining an episode of care at or below the target price increasingly difficult. Discharge disposition and readmission are well established factors that increase hospital cost [7]. However, reduction of these does not seem enough to maintain savings under the CJR model. New cost savings mechanisms such as identification of patients eligible for SDD, and reduction of unnecessary home services resulted in smaller losses of positive margins, though these were still significantly less for CJR than BPCI

Introduction. With the removal of total hip arthroplasty (THA) from the Centers for Medicare & Medicaid Services (CMS) inpatient-only list, understanding predictors of length of stay (LOS) after THA is critical. Thus, we aimed to determine the influence of patient- and procedure-related risk factors as predictors of >1-day LOS after THA. Methods. A prospective cohort of 5,281 patients underwent primary THA between January 2016 and April 2019. Risk factors increased LOS were categorized as patient-related (demographics, smoking status, baseline Veterans RAND 12 Item Health Survey Mental Component Summary score [VR-12 MCS], Charlson Comorbidity Index [CCI], surgical indication, baseline Hip Injury and Osteoarthritis Outcome Score [HOOS] pain subscore and baseline HOOS physical function shortform (HOOS-PS), range of motion, and predicted discharge disposition) or procedure-related (hospital site, surgeon, approach, day of surgery, and surgery start time). By using the Akaike information criterion (AIC) and internally-validated concordance probabilities (C-index) for discriminating a 1-day LOS from a >1-day LOS, we compared performance between a patient-related risk factors only model and a model containing both patient- and procedure-related risk factors. Results. A >1-day LOS was statistically significantly associated with older age (p<0.001), female sex (p<0.001), higher body mass index (BMI) (p<0.001), higher CCI (p<0.001), Medicare status (p=0.012), higher baseline HOOS-PS (P<0.001) and lower baseline VR-12 MCS scores (p<0.001). The C-index after 1,000 bootstrap iterations were 0.693 and 0.883 for patient-related and patient plus procedure-related factors, respectively. Upon addition of procedure-related risk factors to the model, the AIC decreased by approximately 1,100 units, indicating that procedure-related risk factors (especially hospital site and surgical approach) explain LOS more effectively than patient-related risk factors alone. Conclusions. Although patient-related risk factors provide substantial predictive value for LOS following THA, procedure-related risk factors (mainly hospital site and surgical approach) remain the main drivers of predicting LOS. These results can help clinicians select appropriate candidates for short-stay and outpatient THA

Introduction. Cephalomedullary nails (CMN) are commonly used for the treatment of intertrochanteric (IT) hip fractures. Total hip arthroplasty (THA) is commonly used as a salvage procedure for failed IT hip fractures that progress to post-traumatic arthritis. This study analyzed the complications of THA following treatment of failed IT hip fractures with cephalomedullary nails. Methods. Patients who had a primary THA were identified from the 5% subset of Medicare Parts A/B from 2002–2015. A subgroup with previous CMN for IT hip fracture within the previous 5 years was identified and compared to the remaining THA patients without prior CMN. Length of stay (LOS) was compared using both univariate and multivariate analysis. Infection, dislocation, revision, and readmission were compared between those with and without prior CMN, using multivariate analysis (adjusted for demographic, hospital, and clinical factors). Results. 5% subset of the Medicare data yielded 56,522 primary THA, with 369 treated with prior CMN. The percentage of primary THA from 2002–2005 with prior cephalomedullary nails (0.346%) more than doubled in 2012–2015 (0.781%). The prior CMN group tended to be older, female, higher CCI, and lower socioeconomic status. Mean LOS was 1.5 days longer (5.3 vs 3.8) in the prior CMN group (p<0.0001). The percentage of postoperative complications was significantly higher in the prior CMN group compared to non-CMN cohort: infection (6.2% vs 2.6%), dislocation (8.1% vs 4.5%), revision (8.4% vs 4.3%), revision for infection (1.1% vs 0.37%), and revision for dislocation (2.2% vs 0.6%). Discussion. Conversion from failed IT hip fractures with cephalomedullary nails to total hip arthroplasty continues to increase. These cases occur in elderly patients with increased comorbidities. There is a significantly increased risk of infection, dislocation and LOS in the CMN group. Patients with failed IT hip fractures undergoing THA should be made aware of the increased complication risk and further steps need to be undertaken to diminish the elevated risk

The statements contained in this document are solely those of the authors and do not necessarily reflect the views or policies of CMS. The authors assume responsibility for the accuracy and completeness of the information contained in this document. Background. The Bundled Payments for Care Improvement (BPCI) initiative was introduced to reduce healthcare costs while maintaining quality. We examined data from a healthcare system comprised of five hospitals that elected to participate in the BPCI Major Joint Replacement of the Lower Extremity Model 2 initiative beginning July 1, 2015. We compared one hospital that did 439 BPCI hip cases to the four other hospitals that did 459 cases. Stratifying the data by hospital volume, we sought to determine if costs decreased during the BPCI period, how the savings were achieved, and if savings resulted in financial rewards for participation. Methods. The Medicare data included the target cost for each episode (based on historical data from 2009–2012 for each hospital that was adjusted quarterly) and actual Part A and Part B spending for 90 days. Using 1,574 primary hip replacements, we analyzed the costs associated with the anchor hospitalization, inpatient rehabilitation, skilled nursing facilities, home health, outpatient physical therapy and readmission to compare the 898 hips done during the 16-month BPCI initiative period with the 676 hips done during the 1-year period preceding BPCI participation. Owing to the nonparametric distribution of the cost data, a Mann-Whitney U test was used to compare the higher volume hospital with the four lower volume hospitals. Results. Compared to the preceding year, the mean episode of care cost during BPCI participation decreased by 14.1% (from $21,823 to $18,755, p=0.02) at the higher volume hospital and by 13.1% (from $32,138 to $27,940, p=0.02) at the lower volume hospitals. During the BPCI period, the mean Medicare target cost was $18,490 at the higher volume hospital and $25,021 at the lower volume hospitals (p<0.001). At the higher volume hospital, the major components of the savings included $526,028 from reduced readmission rates (11.5% versus 3.0%, p<0.001), $393,757 primarily due to reduced length of stay at skilled nursing facilities (mean 33 days versus 26 days, p=0.07), and $205,459 associated with a decreased percentage of patients using inpatient rehabilitation (6.6% versus 3.2%, p=0.03). At the lower volume hospitals, the major components of the savings included $1,002,447 associated with a reduction in the length of stay at skilled nursing facilities (mean 37 days versus 27 days, p<0.001), $487,356 associated with a decrease in the percentage of patients using inpatient rehab (11.6% versus 6.5%, p=0.01), and $355,695 associated with reduced readmission costs. Despite the savings, the mean reconciliation penalty was $184 per case at the higher volume hospital and $2,309 per case at the lower volume hospitals. Stratified by the type of hip replacement, reconciliation for elective primaries resulted in a mean reward of $848 per case for the 409 hips performed at the higher volume hospital and $2,497 per case for the 266 hips done at the lower volume hospitals. For hip fracture cases, reconciliation resulted in a mean penalty of $14,248 per case among the 30 hips done at the higher volume hospital and $8,932 per case for the 193 hips done at the lower volume hospitals. Conclusions. Based on the reduction in costs and decreased readmission rates, the BPCI initiative is achieving its objectives. Although the higher and lower volume hospitals achieved savings during BPCI participation, the target costs were lower than the actual costs resulting in a reconciliation penalty that was driven by the cost of hip fractures. The reconciliation rewards associated with elective primary THAs compared to the substantial penalties associated with hip fractures support the premise that these groups should have different targets costs

Aims. Lumbar fusion is known to reduce the variation in pelvic tilt between standing and sitting. A flexible lumbo-pelvic unit increases the stability of total hip arthroplasty (THA) when seated by increasing anterior clearance and acetabular anteversion, thereby preventing impingement of the prosthesis. Lumbar fusion may eliminate this protective pelvic movement. The effect of lumbar fusion on the stability of total hip arthroplasty has not previously been investigated. Patients and Methods. The Medicare database was searched for patients who had undergone THA and spinal fusion between 2005 and 2012. PearlDiver software was used to query the database by the International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) procedural code for primary THA and lumbar spinal fusion. Patients who had undergone both lumbar fusion and THA were then divided into three groups: 1 to 2 levels, 3 to 7 levels and 8+ levels of fusion. The rate of dislocation in each group was established using ICD-9-CM codes. Patients who underwent THA without spinal fusion were used as a control group. Statistical significant difference between groups was tested using the chi-squared test, and significance set at p < 0.05. Results. At one-year follow-up, 14 747 patients were found to have had a THA after lumbar spinal fusion (12 079 1 to 2 levels, 2594 3 to 7 levels, 74 8+ levels). The control group consisted of 839 004 patients. The dislocation rate in the control group was 1.55%. A higher rate of dislocation was found in patients with a spinal fusion of 1 to 2 levels (2.96%, p < 0.0001) and 3 to 7 levels (4.12%, p < 0.0001). Patients with 3 to 7 levels of fusion had a higher rate of dislocation than patients with 1 to 2 levels of fusion (odds ratio (OR) = 1.60, p < 0.0001). When groups were matched for age and gender to the unfused cohort, patients with 1 to 2 levels of fusion had an OR of 1.93 (95% confidence interval (CI) 1.42 to 2.32, p < 0.001), and those with 3 to 7 levels of fusion an OR of 2.77 (CI 2.04 to 4.80, p < 0.001) for dislocation. Conclusion. Patients with a previous history of lumbar spinal fusion have a significantly higher rate of dislocation of their THA than age- and gender-matched patients without a lumbar spinal fusion. Cite this article: Bone Joint J 2017;99-B:585–91

Introduction. Patients with FNF may be treated by either total hip arthroplasty (THA) or hemiarthroplasty (HA). Utilizing American Joint Replacement Registry (AJRR) data, we aimed to evaluate outcomes in FNF treatment. Methods. Medicare patients with FNF treated with HA or THA reported to the AJRR database from 2012–2019 and CMS claims data from 2012–2017 were analyzed in this retrospective cohort study. “Early” was defined as less than 90 days from index procedure. A logistic regression model, including index arthroplasty, age, sex, stem fixation method, hospital size. 1. , hospital teaching affiliation. 1. , and Charlson comorbidity index (CCI), was utilized to determine associations between index procedure and revision rates. Results. Of 75,333 FNF procedures analyzed, 82.2% had HA. 8.4% had cemented fixation. 36.9% had cementless fixation. Fixation was unknown for 41,225 (54.7%) patients. 90-day readmissions rates were 1.3% for both cohorts. Both the early revision rate (0.9% HA vs. 1.3% THA, p<0.0001) as well as the overall revision rate (1.5% HA vs. 2.3% THA, p<0.0001) were higher in the THA cohort. The three most common reasons for any revision were instability (26%), infection (21%), and periprosthetic fracture (15%). Higher rates of any revision were associated with cementless fixation (OR=1.37, 95% CI 1.20–1.57) and increased age (OR=0.96, 95% CI 0.96–0.97). THA and increased age were risk factors for early and any revision for instability. Cementless fixation, female sex, and decreased age were associated with lower revision rates for infection. Conclusion. The most common surgical treatment for FNF reported to the AJRR was cementless stem fixation and hemiarthroplasty. The higher revision rates for FNF treatment with THA warrant further investigation. The use of cemented femoral fixation in this patient population may be under-utilized. These data provide a benchmark of US practice for reference and comparison to other practices throughout US and the world

Introduction. The Comprehensive Care for Joint Replacement (CJR) model for total hip arthroplasty (THA) involves a target reimbursement set by the Center for Medicare and Medicaid Services (CMS). Many patients exceed these targets, but predicting risk for incurring these excess costs remains challenging, and we hypothesized that select patient characteristics would adequately predict CJR cost overruns. Methods. Demographic factors and comorbidities were retrospectively reviewed in 863 primary unilateral CJR THAs performed between 2013 and 2017 at a single institution. A predictive model was built from 31 validated comorbidities and a base set of 5 patient factors (age, gender, BMI, ASA, marital status). A multivariable logistic regression model was refined to include only parameters predictive of exceeding the target reimbursement level. These were then assigned weights relative to the weakest parameter in the model. Results. The overall cost of care for 225 patients (26.1%) exceeded the target price, and a comprehensive model containing all 36 parameters demonstrated adequate discrimination (AUC: 0.748). This model was narrowed to 12 parameters retained for their statistical value in predicting excess cost, without substantial loss of predictive ability (AUC: 0.735). A single score formed from the sum of each patient's weighted parameters also showed adequate discrimination (AUC: .732), with predicted risk for exceeding CJR targets ranging from 10% for a patient score of 10 to 80% for a score of 30. Average scores for patients exceeding the target price were significantly higher than those who did not (19.5 vs 15.0, p < 0.0001). Conclusions. A model composed of weighted comorbidities and base demographics provides adequate discrimination in predicting whether THA costs will exceed CJR targets. This not only helps identify patients who may benefit from further pre-operative optimization, but also allows health systems to predict the likely minimum incurred costs for select patients scheduled for surgery

Total joint arthroplasty (TJA) is a high value elective orthopaedic procedure, the indications for which may vary among surgeons as well as patients. The utilization of other discretionary procedures is known to be influenced by the availability of qualified surgeons. We investigated the existence of a correlation between geographic variation in TJA utilization and the regional density of arthroplasty surgeons. The number of Medicare-funded total hip (THA) and total knee (TKA) arthroplasties performed in predetermined geographic referral regions were obtained from the Dartmouth Atlas for 2012. The number of surgeons specializing in total joint arthroplasty in each respective region was derived from the AAHKS membership list. Linear regression was used to assess the relationship between number of arthroplasties performed per 1000 Medicare beneficiaries and the number of AAHKS-members per 100,000 beneficiaries in each Hospital Referral Region (HRR). For THA in aggregate, a positive correlation was found between number of THA performed per 1,000 beneficiaries and increasing TJA surgeon density. Positive correlations were also noted when HRRs were stratified by size from 50,000 to 250,000 beneficiaries. The number of THA performed per 1,000 beneficiaries in regions with AAHKS members was greater than in regions without (4.03 vs 3.29; p=0.008). In contrast, there was no correlation between the rate of TKA utilization and HRR surgeon density, and no consistent relationship between TKA rate and HRRs stratified by size. Likewise, there was no difference in the rate of TKA between HRRs with and without AAHKS members (8.48 vs 8.84; p=0.18). The frequency of THA positively correlates with AAHKS surgeon density in all but the largest HRRs and was greater in regions with AAHKS members than in those without. Such relationships were not apparent for TKA utilization. These data may have important implications for more cost-effective utilization of THA

Aims

This study evaluates the association between consultant and hospital volume and the risk of re-revision and 90-day mortality following first-time revision of primary hip arthroplasty for aseptic loosening.

Use of large databases for orthopaedic research has increased exponentially. Each database represents unique patient populations and vary in methodology of data acquisition. The purpose of this study was to evaluate differences in reported demographics, comorbidities and complications following total hip arthroplasty (THA) amongst four commonly used databases. Patients who underwent primary THA during 2010–2012 were identified within National Surgical Quality Improvement Programs (NSQIP), Nationwide Inpatient Sample (NIS), Medicare Standard Analytic Files (MED) and Humana Claims Database (HAC). NSQIP definitions for comorbidities and surgical complications were queried in NIS, MED, and HAC using coding algorithms. Age, sex, comorbidities, inpatient and 30-day postoperative complications were compared (NIS has inpatient data only). Primary THAs from each database were 22,644 (HAC), 371,715 (MED), 188,779 (NIS) and 27,818 (NSQIP). Age and gender distribution were similar between databases. There was variability in the prevalence of comorbidities and complications depending upon the database and duration of post-operative follow-up. HAC and MED had twice the prevalence of COPD, coagulopathy and diabetes than NSQIP. NSQIP had more than twice the obesity than NIS. HAC had more than twice the rates of 30-day complications at all endpoints compared to NSQIP and more than twice the DVTs, strokes and deep infection as MED at 30-days post-op. Comparison of inpatient and 30-day complications rates demonstrated more than twice the amount of infections and DVTs are captured when analysis is extended from inpatient stay to 30-days post-op. Amongst databases commonly used in orthopaedic research, there is considerable variation in complication rates following THA depending upon the database. It will be important to consider these differences when critically evaluating database research. Additionally, with the advent of bundled payments, these differences must be considered in risk adjustment models

Introduction. Many pharmacologic agents have been used for venous thromboembolism (VTE) prophylaxis after elective total hip arthroplasty (THA). Rivaroxaban was the first novel oral anticoagulant approved for THA patients, but its actual efficacy and safety in clinical practice, beyond randomized trials, is unknown. Materials and Methods. This is a retrospective study, using the Truven Health MarketScan database, of anticoagulation medication prescriptions after elective THA, in both commercially insured (CI) and Medicare supplement insured (MS) patients, from 2010 to 2015. After exclusions, there were 83,179 CI and 50,534 MS patients available for analysis. There were 12,876 new users of warfarin (W) and 10,892 new users of rivaroxaban (R) in CI patients, and 7,416 new users of W and 4,739 new users of R in MS patients. We asked the following questions: (1) What were the trends and predictive factors for anticoagulant use after elective THA? (2) What was the actual clinical efficacy: frequency of deep vein thrombosis (DVT) and pulmonary embolism (PE), and frequency of adverse events within 90 days with the two most commonly used oral agents, rivaroxaban and warfarin, from June 2011 to September 2015? Data was analyzed for each anticoagulant by odds ratios using logistic regression models with stabilized inverse probability treatment weighting. Results. There was a change in use of anticoagulants after R approval. Use of W decreased from approximately 50% each in 2010 in both insurance cohorts to 10% in CI patients and 30% in MS patients in 4th quarter 2015. The use of R increased from 0 to 33% in both cohorts from 2011 to 2015. In the multivariate analysis, in CI patients, females had lower odds of getting R, and patients in Western region had higher odds of getting R; in MS patients, increasing age had reduced odds of getting rivaroxiban, but Western region and surgery in 2015 had higher odds. Patients with capitated insurance plans and renal impairment had lower odds of R initiation, but a history of cardiovascular disease or hypertension had higher odds. In 90 days after THA, patients given R had significantly lower odds ratio of both DVT and PE in both CI patients (DVT: 1.54 with W, 0.54 with R; PE: 2.12 with W, 0.73 with R) and MS patients (DVT: 3.01 W, 1.73 R; PE: 4.09 W, 1.88 R). With logistic regression analysis, users of W had significantly higher odds ratio of both DVT (CI 2.63 and MS 1.78) and PE (CI 2.60 and MS 2.09) than R. There was no significant difference in rates of bleeding between W and R, but W had higher odds ratio than R of prosthetic joint infection (PJI) in both CI (1.574) and MS (1.790) cohorts. Conclusions. There has been an increase in VTE prophylaxis with R, and a decrease in both W and LMWH use after elective THA over four years. Patient factors, insurance type, and comorbidities were associated with this change. In actual clinical efficacy, R had lower odds ratio of both DVT and PE than W, and bleeding risks were similar. The association of W with an increased odds ratio of PJI compared to R requires further study

Nobel Prize winning economist Paul Krugman described Moral Hazard as “…any situation in which one person makes the decision about how much risk to take, while someone else bears the cost if things go badly”. The fidelity of some surgeons to their patients has been brought into question by recent press reports exposing a practice whereby one attending surgeon will be responsible for two patients undergoing surgery simultaneously. This is variously referred to as Overlapping Surgery, Concurrent Surgery, Simultaneous Surgery, Double-Booked Surgery or Ghost Surgery. This practice entails surgeons in training (residents and fellows) performing varying degrees of the patient's surgery while the attending surgeon is operating elsewhere. In general, the patient is not informed of this substitution. When informed, most would not allow it. Defenders of this practice site surgeon and hospital “efficiency”, independent operating experience by trainees, mass casualty triage and access to “in-demand” specialists. Critics feel it “is a breach of ethical behavior”, that “The most likely motive for this is profit for both the surgeon and hospital” and “Overlapping surgery… threatens our obligation as orthopaedic surgeons to respect the primacy of patient welfare…”. The American College of Surgeons, in response to public disclosures, created a policy on Overlapping Surgery. Its executive director wrote, “It is essential that the patient be informed of this practice and given enough notice so they may decide whether to seek care from another surgeon or at another institution*. The US Senate Finance Committee investigated Overlapping/Concurrent Surgery practices. It expressed concerns over − 1) lack of informed consent, 2) plausible risks to patient safety, 3) use of Medicare billing regulations to determine acceptable surgical practices and 4) surgeons self- defining the “critical part” of the operation. Studies to date do not resolve the propriety of this practice. All but one is short term. Most show longer surgical durations. Most show no increase in 30-day complication rates. The only long- term study found a 90% increase in complication rate in hip procedures at one year when surgery overlapped. None document the location of the surgeon during the procedure or report efficacy. Over 7 million living Americans are beneficiaries of either a total hip or total knee replacement. These patients are made whole, their suffering relieved, their function and lives restored. These miracles of modern medicine are not without cost. The United States spends $3.5 trillion dollars annually on health care, almost 20% of our GDP. Delivering health care is a grave responsibility and any person involved in it must understand the importance and consequences of their actions. The third leading cause of American deaths is medical errors. A recent study estimated that 4 out of 100 patients entering the hospital for surgery will die within seven days. Recognizing this, a surgeon's role as a patient's moral fiduciary, concerned primarily with protecting the interests of the patient, must be honored as a sacred trust. The financial pressure on the surgeon from stagnant surgical fees is the elephant in the room that must be addressed in relation to this matter. When fees are cut, surgeons operate more. Plato, in The Republic, recounts an allegory about a magic ring that makes its wearer invisible. He asks the question; Will the power of anonymity eliminate morality and ethics? When we as surgeons become “invisible” to our anesthetized patients during surgery, how will we answer that question?

Aims

Obesity is associated with an increased risk of hip osteoarthritis, resulting in an increased number of total hip arthroplasties (THAs) performed annually. This study examines the peri- and postoperative outcomes of morbidly obese (MO) patients (BMI ≥ 40 kg/m²) compared to healthy weight (HW) patients (BMI 18.5 to < 25 kg/m²) who underwent a THA using the anterior-based muscle-sparing (ABMS) approach.

Aims

The aim of this study was to estimate the clinical and economic burden of dislocation following primary total hip arthroplasty (THA) in England.