Faculty Bibliography

Prosthetic joint infection (PJI) remains a major cause of failure in total joint arthroplasty. This complication begets an increase in morbidity and mortality along with significant costs to the healthcare system. The use of prophylactic antibiotics has significant decreased the incidence of this complication. However, the incidence of PJI has not drastically decreased over the last 50 years. This review explores the history, current concepts, and future developments for prevention of PJI prior to incision in total joint arthroplasty.

BACKGROUND/UNASSIGNED:Increased load bearing across the patellofemoral and tibiofemoral articulations has been associated with total knee arthroplasty (TKA) complications. Therefore, the purpose of this study was to quantify the biomechanical characteristics of the patellofemoral and tibiofemoral joints and simulate varying weight-bearing demands after posterior cruciate ligament-retaining (CR) and posterior-stabilized (PS) TKAs. METHODS/UNASSIGNED:Eight fresh-frozen cadaveric knees (average age, 68.4 years; range, 40-86 years) were tested using a custom knee system with muscle-loading capabilities. The TKA knees were tested with a CR and then a PS TKA implant and were loaded at 6 different flexion angles from 15° to 90° with progressively increasing loads. The independent variables were the implant types (CR and PS TKA), progressively increased loading, and knee flexion angle (KFA). The dependent variables were the patellofemoral and tibiofemoral kinematics and contact characteristics. RESULTS/UNASSIGNED:The results showed that at higher KFAs, the position of the femur translated significantly more posterior in CR implants than in PS implants (36.6 ± 5.2 mm and 32.5 ± 5.7 mm, respectively). The patellofemoral contact force and contact area were significantly greater in PS than in CR implants at higher KFAs and loads (102.4 ± 12.5 N and 88.1 ± 10.9 N, respectively). Lastly, the tibiofemoral contact force was significantly greater in the CR than the PS implant at flexion angles of 45°, 60°, 75°, and 90° KFA, the average at these flexion angles for all loads tested being 246.1 ± 42.1 N and 192.8 ± 54.8 N for CR and PS implants, respectively. CONCLUSIONS/UNASSIGNED:In this biomechanical study, CR TKAs showed less patellofemoral contact force, but more tibiofemoral contact force than PS TKAs. For higher loads across the joint and at increased flexion angles, there was significantly more posterior femur translation in the CR design with a preserved posterior cruciate ligament and therefore significantly less patellofemoral contact area and force than in the PS design. The different effects of loading on implants are an important consideration for physicians as patients with higher load demands should consider the significantly greater patellofemoral contact force and area of the PS over the CR design.

BACKGROUND:The impact of increased patient comorbidities on the cost-effectiveness of total hip arthroplasty (THAs) is lacking. This study aimed to compare revenue, costs, and short-term (90 days) surgical outcomes between patients who have and do not have a high comorbidity burden (HCB). METHODS:We retrospectively reviewed 14,949 patients who underwent an elective, unilateral THA between 2012 and 2021. Patients were stratified into HCB (Charlson Comorbidity Index ≥ 5 and American Society of Anesthesiology scores of 3 or 4) and non-HCB groups, and were further 1:1 propensity matched based on baseline characteristics. Perioperative data, revenue, costs, and contribution margins (CMs) of the inpatient episode were compared between groups. Also, 90-day readmissions and revisions were compared between groups. Of the 11,717 patients who had available financial data (n = 1,017 HCB, n = 10,700 non-HCB), 1,914 patients were included in the final matched analyses (957 per group). RESULTS:Total (P < .001) and direct (P < .001) costs were significantly higher for HCB patients. Comparable revenue between cohorts (P = .083) resulted in a significantly decreased CM in the HCB patient group (P < .001). The HCB patients were less likely to be discharged home (P < .001) and had significantly higher 90-day readmission rates (P = .049). CONCLUSIONS:Increased THA costs for HCB patients were not matched by increased revenue, resulting in decreased CM. Higher rates of nonhome discharge and readmissions in the HCB population add to the additional financial burden. Adjustments to the current reimbursement models should better account for the increased financial burden of HCB patients undergoing THA and ensure access to care for all patient populations. LEVEL OF EVIDENCE/METHODS:III.

BACKGROUND:A survey was conducted at the 2023 Annual Meeting of the American Association of Hip and Knee Surgeons (AAHKS) to assess practice management strategies among current AAHKS members. METHODS:Members of AAHKS used an app to answer both multiple-choice and "yes or no" questions related to a variety of issues related to their practices. RESULTS:The number of AAHKS members in private practice (37%) continues to decline, and 4% are now in private equity-employed practices. Fee for service (30%) and relative value units (30%) are the major forms of compensation. The number of AAHKS members that perform total joint arthroplasties at ambulatory surgery centers continues to increase, and supply chain issues (91%) remain a problem. There has been a decrease in surgeon participation in bundled payment programs and gainsharing arrangements with hospitals. CONCLUSIONS:This member's survey provides valuable information regarding practice patterns. The shift to outpatient surgery has continued. Future surveys will be performed to monitor changes in practice patterns over time.

This article addresses the challenges surrounding hip and knee osteoarthritis (OA) treatment in Jehovah's Witnesses (JWs), focusing on the complexities arising from their refusal of blood products and transfusions. Acknowledging the heightened risk of blood loss anemia during joint replacement surgery, this review explores documented strategies that enable safe elective joint arthroplasty in JW patients, emphasizing comparable initial diagnostic methods and non-operative treatments up until the pre-operative stage. Special considerations should be taken in the perioperative and intraoperative stage. Despite these challenges, safe arthroplasty is feasible with satisfactory outcomes through a combination of careful preoperative optimization, blood saving protocols, and cultural sensitivity.

BACKGROUND:The Hip Disability and Osteoarthritis Outcome Score (HOOS JR) is a widely used patient-reported outcome measures questionnaire for total hip arthroplasty (THA). However, not all patients choose to complete HOOS JR, and thus, a subset of the THA population may be underrepresented. This study aims to investigate the association between patient demographic factors and HOOS JR response rates. METHODS:This was a retrospective cohort study of adult, English-speaking patients who underwent primary THA by a fellowship-trained arthroplasty surgeon between 2017 and 2023 at a single, high-volume academic institution. The HOOS JR completion status-complete or incomplete-was recorded for each patient within 90 days of surgery. Standard statistical analyses were performed to assess completion against multiple patient demographic factors. RESULTS:Of the 2,908 total patients, 2,112 (72.6%) had complete and 796 (27.4%) had incomplete HOOS JR questionnaires. Multivariate analysis yielded statistical significance (P < .05) for the distribution of patient age, race, insurance, marital status, and income quartile with respect to questionnaire completion. Patient sex or religion did not affect response rates. Failure to complete HOOS JR (all P < .001) was associated with patients aged 18 to 39 (59.8%), who identified as Black (36.4%) or "other" race (39.6%), were never married (38%), and were in the lower half income quartiles (43.9%, 35.9%) when compared to the overall incomplete rate. CONCLUSIONS:Multiple patient demographic factors may affect the HOOS JR response rate. Overall, our analyses suggest that older patients who identify as White and are of higher socioeconomic status are more likely to participate in the questionnaire. Efforts should focus on capturing patient groups less likely to participate to elucidate more generalizable trends in arthroplasty outcomes.

INTRODUCTION/BACKGROUND:Following removal of total hip arthroplasty (THA) from the inpatient only (IPO) list by the Center for Medicare Services (CMS), arthroplasty surgeons face increased pressure to perform procedures on an outpatient (OP) basis. The purposes of the present study were to compare patients booked for THA as OP who required conversion to IP status postoperatively, to patients who were booked as, and remained OP, and to identify factors predictive of conversion from OP to IP status. METHODS:We retrospectively reviewed all patients who underwent a primary THA at our institution between January 1, 2020 and April 26, 2022. All patients included were originally scheduled for OP surgery and were separated based on conversion to IP status postoperatively. Multiple regression analyses were used to determine the significance of all perioperative variables. Modeling via binary logistic regressions were used to determine factors predictive of status conversion. RESULTS:Of 1,937 patients, 372 (19.2%) designated as OP preoperatively required conversion to IP status postoperatively. These patients had significantly higher facility discharge rates (P < 0.001) and 90-day readmission rates (P = 0.024). Patients aged 65 and older (P < 0.001), females (P < 0.001), patients with Black/African American race (P = 0.027), with a recovery room arrival time after 12 pm (P < 0.001), with a BMI > 30 kg/m2 (P = 0.001), and with a Charlson Comorbidity Index (CCI) ≥ 4 (P = 0.013) were Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation more likely to require conversion to IP designation. Marital status and time of procedure were also significant factors, as patients who were married (P < 0.001) and who were the first case of the day (P < 0.001) were less likely to be converted to IP. CONCLUSION/CONCLUSIONS:Several factors were identified which could help determine appropriate hospital designation status at the time of surgical booking to ultimately avoid insurance claim denials. These included BMI, certain demographic factors, CCI ≥ 4, and patients 65 or older. LEVEL III EVIDENCE/METHODS:Retrospective Cohort Study.

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.