Faculty Bibliography

BACKGROUND:Periprosthetic femoral fractures (PFF) carry significant morbidity following arthroplasty for femoral neck fracture (FNF). This study assessed fracture complications following arthroplasty for FNF and the effect of cement fixation of the femoral component on intraoperative and post-operative PFF. METHODS:Between February 2014 and September 2021, 740 patients with a FNF who underwent arthroplasty were analyzed for demographics, surgical management, use of cement for fixation of the femoral component, and subsequent PFF. Variables were compared with Mann-Whitney or Chi-square as appropriate. Multivariate logistic regression was used to assess independent risk factors associated with intraoperative or post-operative PFF. RESULTS:There were 163 THAs (41% cemented) and 577 HAs (95% cemented). There were 28 PFFs (3.8%): 18 post-operative and 10 intraoperative. Fewer post-operative PFFs occurred with cemented stems (1.63% vs. 6.30%, p = 0.002). Mean time from surgery to presentation with post-operative PFF was 14 months (0-45 months). Mean follow-up time was 10.3 months (range: 0-75.7 months). In multivariate regression, use of cement and THA was independently associated with decreased post-operative PFF (cement: OR 0.112, 95% CI 0.036-0.352, p < 0.001 and THA: OR 0.249, 95% CI 0.064-0.961, p = 0.044). More intraoperative fractures occurred during THA (3.68% vs. 0.69%, p = 0.004) and non-cemented procedures (5.51% vs. 0.49%, p < 0.001). In multivariate regression, use of cement was protective against intraoperative fracture (OR 0.100, CI 0.017-0.571, p = 0.010). CONCLUSIONS:In patients with a FNF treated with arthroplasty, cementing the femoral component is associated with a lower risk of intraoperative and post-operative PFF. Choice of procedure may be based on patient factors and surgeon preference.

BACKGROUND:Financial analyses of simultaneous bilateral total knee arthroplasty versus staged bilateral total knee arthroplasty (simBTKA and staBTKA, respectively) have shown improved cost-effectiveness of simBTKA, though revenue and contribution margin (CM) for these procedures have not been investigated. Our analyses compared surgical outcomes, revenues, and CMs between simBTKA and staBTKA. METHODS:We retrospectively reviewed all patients who underwent simBTKA (both procedures done on the same day) and staBTKA (procedures done on a different day within one year) between 2012 and 2021. Patients were 1:1 propensity matched based on baseline characteristics. Surgical outcomes, as well as revenue, cost, and CM of the inpatient episode were compared between groups. Of the 2,357 patients evaluated (n = 595 simBTKA, n = 1,762 staBTKA), 410 were included in final matched analyses (205 per group). RESULTS:Total (P < .001) and direct (P < .001) costs were significantly lower for simBTKA procedures compared to overall costs of both staBTKA procedures. Significantly lower revenue for simBTKA procedures (P < .001), resulted in comparable CM between groups (P = .477). Postoperative complications including 90-day readmission (P = 1.000), 90-day revision (P = 1.000) and all-cause revision at latest follow-up (P = .083) were similar between groups. CONCLUSIONS:In our propensity-matched cohort, lower costs for simBTKA compared to staBTKA were matched by lower revenues, with a resulting similar CM between procedures. Given that postoperative complication rates were similar, both procedures had comparable cost-effectiveness. Future research is needed to identify patients for whom simBTKA may represent a better surgical intervention compared to staBTKA with respect to clinical and patient reported outcomes.

INTRODUCTION/BACKGROUND:Over the past decades, utilization of total hip arthroplasty (THA) has steadily increased. Understanding the demographic trends of THA patients can assist in projecting access to care. This study sought to assess the temporal trends in THA patient baseline characteristics and socioeconomic factors. METHODS:, 2022. Demographic data, including age, sex, race, body mass index (BMI), Charlson Comorbidity Index (CCI), insurance, and socioeconomic status (SES), as determined by median income by patients' zip code, were collected. The trends of these data were analyzed using the Mann-Kendall test. RESULTS:Over the past decade at our institution, patient age (2013: 62.1 years to 2022: 65.1 years, P = 0.001), BMI (2013: 29.0 to 2022: 29.5, P = 0.020), and mean CCI (2013: 2.4 to 2022: 3.1, P = 0.001) increased. The proportion of Medicare patients increased from 48.4% in 2013 to 54.9% in 2022 (P = 0.001). The proportion of African American patients among the THA population increased from 11.3% in 2013 13.0% in 2022 (P = 0.012). Over this period, 90-day readmission and 1-year revision rates did not significantly change (2013: 4.8 and 3.0% to 2022: 3.4 and 1.4%, P = 0.107 and P = 0.136, respectively). The proportion of operations using robotic devices also significantly increased (2013: 0% to 2022: 19.1%; P < 0.001). CONCLUSION/CONCLUSIONS:In the past decade, the average age, BMI, and comorbidity burden of THA patients have significantly increased, suggesting improved access to care for these populations. Similarly, there have been improvements in access to care for African American patients. Along with these changes in patient demographics, we found no change in 90-day readmission or 1-year revision rates. Continued characterization of the THA patient population is vital to understanding this demographic shift and educating future strategies and improvements in patient care.

BACKGROUND:Though previous studies have demonstrated improved cost benefits associated with simultaneous versus staged bilateral total hip arthroplasty (simBTHA and staBTHA), further investigation is needed regarding the revenues and contribution margins (CMs) of these procedures. In this study, we compared revenue, CM, and surgical outcomes between simBTHA and staBTHA. METHODS:All patients who underwent simBTHA (both procedures completed the same day) and staBTHA (procedures completed on different days within one year) between 2011 and 2021 at a single high-volume orthopedic specialty hospital were identified. Of the 1,517 identified patients (n = 139 simBTHA, n = 1,378 staBTHA), 232 were included in a 1:1 propensity match based on baseline demographics (116 per cohort). Revenue, costs, CM, and surgical outcomes were compared between cohorts. RESULTS:Compared to staBTHA, simBTHA procedures had significantly lower total costs (P < .001), direct costs (P < .001), and patient revenue. There was no significant difference in CM between groups (P = .361). Additionally, there were no significant differences in length of stay (P = .173), operative time (P = .438), 90-day readmissions (P = .701), 90-day revisions (P = .313), or all-cause revisions (P = .701) between cohorts. CONCLUSIONS:Though simBTHA procedures have lower revenues than staBTHA, they also have lower costs, resulting in similar CM between procedures. As both procedures have similar postoperative complication rates, further research is required to evaluate specifically which patients may benefit from simBTHA versus staBTHA regarding clinical and patient-reported outcomes. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:As worldwide utilization of total knee arthroplasty (TKA) broadens, demographic trends can help make projections to inform access to care. This study aimed to assess the temporal trends in the socioeconomic and medical demographics of patients undergoing TKA. METHODS:A retrospective review of 15,848 patients who underwent primary, elective TKA at an urban, New York City-based academic medical center between January 2013 and September 2022 was performed. Trends in patients' age, body mass index (BMI), socioeconomic status (SES) (based on median income by patients' ZIP code), race, and Charlson comorbidity index were evaluated using the Mann-Kendall test. RESULTS:In the last decade, mean patient age (65 to 68 years, P < .001) and Charlson comorbidity index (1.4 to 2.3, P < .001) increased significantly. The proportion of patients who had a BMI ≥ 30 and < 40 increased (43.8 to 51.2%, P = .002), while the proportion of patients who had a BMI ≥ 40 (13.7 to 12.1%, P = .015) and BMI < 30 (42.5 to 36.8%, P = .020) decreased. The distribution of patients' race and SES did not change from 2013 to 2022; Black (18.1 to 16.8%, P = .211) and low SES (12.9 to 11.3%, P = .283) patients consistently represented a minority of TKA patients. CONCLUSIONS:Over the last decade, the average age and comorbidity burden of TKA patients at our institution have increased. This portends the need for higher levels of preoperative optimization and postoperative management for TKA patients. A decreased prevalence of BMI ≥40 could reflect optimization efforts. However, the consistently low prevalence of Black and low-SES patients suggests that recent payment models did not improve access to care for these populations. LEVEL OF EVIDENCE/METHODS:IV.

INTRODUCTION/BACKGROUND:The direct anterior approach (DAA) and posterior approach (PA) for total hip arthroplasty (THA) have advantages and disadvantages, but their physiologic burden to the surgeon has not been quantified. This study was conducted to determine whether differences exist in surgeon physiological stress and strain during DAA in comparison to PA. METHODS:We evaluated a prospective cohort of 144 consecutive cases (67 DAA and 77 PA). There were five, high-volume, fellowship-trained arthroplasty surgeons who wore a smart-vest that recorded cardiorespiratory data while performing primary THA DAA or PA. Heart rate (beats/minute), stress index (correlates with sympathetic activations), respiratory rate (respirations/minute), minute ventilation (liters/min), and energy expenditure (calories) were recorded, along with patient body mass index and operative time. Continuous data was compared using T-tests or Mann Whitney U tests, and categorical data was compared with Chi-square or Fischer's exact tests. RESULTS:There were no differences in patient characteristics. Compared to PA, performing THA via DAA had a significantly higher surgeon stress index (17.4 versus 12.4; P < 0.001), heart rate (101 versus 98.3; P = 0.007), minute ventilation (21.7 versus 18.7; P < 0.001), and energy expenditure per hour (349 versus 295; P < 0.001). However, DAA had a significantly shorter operative time (71.4 versus 82.1; P = 0.001). CONCLUSION/CONCLUSIONS:Surgeons experience significantly higher physiological stress and strain when performing DAA compared to PA for primary THA. This study provides objective data on energy expenditure that can be factored into choice of approach, case order, and scheduling preferences, and provides insight into the work done by the surgeon.

BACKGROUND:Utilization of total knee arthroplasty (TKA) continues to rise among patients who have a high comorbidity burden (HCB). With changes in reimbursement models over the past decade, it is essential to assess the financial impact of HCB TKA on healthcare systems. This study aimed to examine trends in revenue and costs associated with TKA in HCB patients over time. METHODS:Of 14,978 TKA performed at a large, urban academic medical center between 2013 and 2021, we retrospectively analyzed HCB patients (Charlson comorbidity index ≥ 5 and American Society of Anesthesiology scores of 3 or 4). A total of 1,156 HCB TKA patients who had complete financial data were identified. Patient demographics, perioperative data, revenue, costs, and contribution margin were collected for each patient. Changes in these financial values over time, as a percentage of 2013 values, were analyzed. Linear regression was performed with a trend analysis to determine significance. RESULTS:From 2013 to 2021, the percentage of HCB TKAs per year increased from 4.2% in 2013 to 16.5% in 2021 (P < .001). The revenue of TKA in HCB patients remained steady (P = .093), while direct costs increased significantly (32.0%; P = .015), resulting in a decline of contribution margin to a low of 82.3% of 2013 margins. There was no significant change in rates of 90-day complications or home discharge following HCB TKA during the study period. CONCLUSIONS:The results of this study indicate a major rise in cost for TKA among HCB patients, without a corresponding rise in revenue. As more patients who have HCB become candidates for TKA, the negative financial impact on institutions should be considered, as payments to institutions do not adequately reflect patient complexity. A re-evaluation of institutional payments for medically complex TKA patients is warranted to maintain patient access among at-need populations.

BACKGROUND:With the increasing utilization of total hip arthroplasty (THA) in patients who have a high comorbidity burden (HCB), coinciding with modifications to reimbursement models over the past decade, an evaluation of the financial impact of HCB on THA over time is warranted. This study aimed to investigate trends in revenue and cost associated with THA in HCB patients. METHODS:Of 13,439 patients who had primary, elective THA between 2013 and 2021 at our institution, we retrospectively reviewed 978 patients considered to have HCB (Charlson comorbidity index ≥ 5 and American Society of Anesthesiology scores 3 or 4). We collected patient demographics, perioperative data, revenue, cost, and contribution margin (CM) of the inpatient episode. We analyzed changes as a percentage of 2013 values over time for these financial markers. Linear regression determined trend significance. The final analysis included 978 HCB patients who had complete financial data. RESULTS:Between 2013 and 2021, direct costs increased significantly (P = .002), along with a nonsignificant increase in total costs (P = .056). While revenue remained steady during the study period (P = .486), the CM decreased markedly to 38.0% of 2013 values, although not statistically significant (P = .222). Rates of 90-day complications and home discharge remained steady throughout the study period. CONCLUSIONS:Increasing costs for HCB patients undergoing THA were not matched by an equivalent increase in revenue, leading to dwindling CMs throughout the past decade. Re-evaluation of reimbursement models for THA that account for patients' HCB may be necessary to preserve broad access to care. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:Current data evaluating the clinical value and cost-effectiveness of advanced diagnostic tests for periprosthetic joint infection (PJI) diagnosis, including alpha-defensin and synovial C-reactive protein (CRP), is conflicting. This study aimed to evaluate the adequacy of preoperative and intraoperative PJI workups without utilizing these tests. METHODS:This retrospective analysis identified all patients who underwent revision total knee or hip arthroplasty (rTKA and rTHA, respectively) for suspected PJI between 2018 and 2020 and had a minimum follow-up of two years. Perioperative data and lab results were collected, and cases were dichotomized based on whether they met the 2018 Musculoskeletal Infection Society (MSIS) criteria for PJI. In total, 204 rTKA and 158 rTHA cases suspected of PJI were reviewed. RESULTS:Nearly 100% of the cases were categorized as "infected" for meeting the 2018 MSIS criteria without utilization of alpha-defensin or synovial CRP (rTKA: n = 193, 94.6%; rTHA: n = 156, 98.7%). Most cases were classified as PJI preoperatively by meeting either the major MSIS or the combinational minor MSIS criteria of traditional lab tests (rTKA: n = 177, 86.8%; rTHA: n = 143, 90.5%). A subset of cases was classified as PJI by meeting combinational preoperative and intraoperative MSIS criteria (rTKA: 16, 7.8%; rTHA: 13, 8.2%). Only 3.6% of all cases were considered "inconclusive" using preoperative and intraoperative data. CONCLUSION/CONCLUSIONS:Given the high rate of cases satisfying PJI criteria during preoperative workup using our available tests, the synovial alpha-defensin and synovial CRP tests may not be necessary in the routine diagnostic workup of PJI. We suggest that the primary PJI workup process should be based on a stepwise algorithmic approach with the most economical testing necessary to determine a diagnosis first. The use of advanced, commercialized, and costly biomarkers should be utilized only when traditional testing is indeterminate.