Faculty Bibliography

BACKGROUND:Demographic variables play an important role in outcomes following revision total hip arthroplasty (rTHA). Surgical and in-patient variables as well as outcomes vary between indications for rTHA. The purpose of this study was to investigate the impact of the indication for the rTHA on costs and postoperative outcomes. METHODS:This retrospective cohort analysis investigated all patients who underwent unilateral, aseptic rTHA at an academic orthopaedic specialty hospital who had at least 1-year postoperative follow-up. In total, 654 patients were evaluated and categorized based on their indication for aseptic rTHA. Demographics, direct and total procedure costs, surgical factors, postoperative outcomes, and re-revision rates were collected and compared between indications. RESULTS:Younger patients had the greatest leg length discrepancy (LLD) and older patients had the highest incidence of periprosthetic fracture (PPF) (P = .001). The greatest proportion of full revisions were found for LLD (16.7%) and head/polyethylene liner-only revisions for metallosis/adverse tissue reaction (100%). Operative time was significantly longest for LLD revisions and shortest for metallosis/adverse tissue reaction revisions (P < .001). Length of stay was longest for periprosthetic fracture and shortest for LLD and stiffness/heterotopic ossification (P < .001). Re-revision rate was greatest for implant failure and lowest for LLD. Total cost was highest for PPF (148.9%) and lowest for polyethylene liner wear (87.7%). CONCLUSIONS:Patients undergoing rTHA for indications such as PPF and aseptic loosening were associated with longer operative times, length of stay and higher total and direct costs. Therefore, they may need increased perioperative attention with respect to resource utilization, risk stratification, surgical planning, and cost-reducing measures. LEVEL III EVIDENCE/METHODS:Retrospective Cohort Study.

BACKGROUND:The prevalence of obesity in total hip arthroplasty (THA) patients has been studied in the past. However, there has not been direct comparison against obesity in the general population. This study compared yearly trends in BMI and obesity rates between patients who had undergone primary THA and those from the general patient population. METHODS:We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA and those who had an annual routine physical exam between January 2013 and December 2020 at our academic tertiary medical center. Baseline demographics were controlled in our statistical models. Significance of yearly trends was determined through a linear regression analysis. Independent samples t-test and Chi-square test were used to compare means and proportions between the two groups, respectively. RESULTS:A total of 11,250 primary THA patients and 1,039,918 annual physical exam patients were included. Average BMI for the THA group was significantly higher (P < 0.001) each year compared to the annual physicals group (APG). Higher obesity rates were observed in all obesity subgroups (all classes, and class I-III individually) for THA patients each year compared to the APG. Interestingly, while we found a significantly increasing trend in obesity for the general population (P < 0.001), BMI and obesity rates remained stable in the THA population. CONCLUSION/CONCLUSIONS:While our general patient population showed significant increase in BMI and obesity over time, THA patients had higher, yet stable, BMI. Further investigation is required to determine the role of risk optimization in these findings. LEVEL III EVIDENCE/METHODS:Retrospective Cohort Study.

INTRODUCTION/BACKGROUND:The purpose of this study is to report on the association between the number of stairs to enter home and length of stay (LOS), discharge disposition, and patient reported outcome measures (PROMs) among patients who underwent primary total joint arthroplasty (TJA). MATERIALS AND METHODS/METHODS:We retrospectively reviewed patients who underwent primary total hip or knee arthroplasty between January 2016 and March 2020. Only patients with documentation of the number of stairs to enter their homes were included in the study. The two cohorts were separated into four groups: none, 1-10, 11-20, and > 20 stairs. Collected variables included demographic data, LOS, discharge disposition, and PROMs. Chi-square and ANOVA were utilized to determine significance. RESULTS:Of the 1116 patients included, 510 underwent THA, and 606 underwent TKA. There was no statistical difference in LOS (THA: p = 0.308; TKA: p = 0.701) and discharge disposition (THA: p = 0.371; TKA: p = 0.484) in both cohorts regardless the number of stairs. There was no statistical difference in FJS-12 scores at 3 months (THA: p = 0.590; TKA: p = 0.206), 12 months (THA: p = 0.217; TKA: p = 0.845), and 21 months (THA: p = 0.782; TKA: p = 0.296) postoperatively for both cohorts. There was no statistical difference in HOOS, JR scores preoperatively (p = 0.278) and at 3 months postoperatively (p = 0.527) for the THA cohort, as well as KOOS, JR scores preoperatively and at 3 and 12 months postoperatively (p = 0.557; p = 0.522; p = 0.747) for the TKA cohort. CONCLUSION/CONCLUSIONS:We found no statistical differences in LOS, discharge disposition, and PROMs in patients who underwent TJA, irrespective of the number of stairs negotiated to enter their home. These findings can aid surgeons to provide preoperative education and reassurance to patients who have concerns with their discharge planning due to the walk-up stairway at their residence.

PURPOSE/OBJECTIVE:The clinical impact of postoperative venous thromboembolism (VTE) following total joint arthroplasty (TJA) remains unclear. In this study, we evaluate the effect of VTE following TJA on postoperative outcomes including discharge disposition, readmission rates, and revision rates. METHODS:We retrospectively reviewed all patients over the age of 18 who underwent primary, elective THA or TKA between 2013 and 2020. Patients were stratified into two cohorts based on whether or not they had a VTE following their procedure. Baseline patient demographics and clinical outcomes such as readmissions and revisions were collected. Propensity score matching was performed to limit significant demographic differences, while independent sample t-tests and Pearson's chi-squared test were used to compare outcomes of interest between the groups. RESULTS:, p = 0.032). All other patient demographics were similar. Compared to the non-VTE cohort, the VTE cohort was less likely to be discharged home (66.1% vs 80.7%; p = 0.021), had a higher rate of 90-day all-cause readmissions (27.5% vs 9.2%, p = 0.001), and a higher two-year revision rate (11.0% vs 0.9%, p = 0.003). CONCLUSION/CONCLUSIONS:Patients with postoperative VTE were less likely to be discharged home and had higher 90-day readmission and two-year revision rates. Therefore, mitigating perioperative risk factors, initiating appropriate long-term anticoagulation, and maintaining close follow-up for patients with postoperative VTE may play significant roles in decreasing hospital costs and the economic burden to the healthcare system. LEVEL OF EVIDENCE III/UNASSIGNED:Retrospective Cohort Study.

INTRODUCTION/BACKGROUND:Although tourniquet use in primary total knee arthroplasty (TKA) has been widely studied, the outcomes associated with tourniquet use in revision TKA (rTKA) remains relatively unexplored. This study investigates surgical outcomes and patient satisfaction in association with tourniquet use during aseptic rTKA. METHODS:We retrospectively reviewed all patients who underwent rTKA for aseptic causes at our institution from 2011-2020. Patients were separated into two cohorts based on tourniquet inflation during the procedure. Outcomes of interest included estimated blood loss (EBL), change in hemoglobin (Hb), surgical time, length-of-stay (LOS), reoperation rate, and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS,JR) scores. RESULTS:Of the 1,212 patients included, 1,007 (83%) underwent aseptic rTKA with the use of a tourniquet and 205 (17%) without the use of a tourniquet. The mean tourniquet inflation time was 93.0 minutes (SD:33.3 minutes). Blood loss was significantly less for patients in the tourniquet cohort as measured through EBL(224.1vs.325.1 mL,p<0.001) and change in preoperative to postoperative Hb(1.75vs.2.04 g/dL,p<0.001). There were no statistical differences in surgical time(p=0.267) and LOS(p=0.206) between the two groups. The reoperation rate was significantly greater for patients who did not have a tourniquet utilized (20.5%vs.15.0%,p=0.038). Delta improvement in KOOS,JR scores from baseline to 3-months postoperatively did not statistically differ between the two cohorts (p=0.560). CONCLUSION/CONCLUSIONS:While delta improvements in KOOS,JR scores were similar for both cohorts, patients who did not have a tourniquet inflated during aseptic rTKA had increased blood loss and were more likely to undergo subsequent reoperation compared to patients who did.

AIMS/OBJECTIVE:Although readmission has historically been of primary interest, emergency department (ED) visits are increasingly a point of focus and can serve as a potentially unnecessary gateway to readmission. This study aims to analyze the difference between primary and revision total joint arthroplasty (TJA) cases in terms of the rate and reasons associated with 90-day ED visits. METHODS:We retrospectively reviewed all patients who underwent TJA from 2011 to 2021 at a single, large, tertiary urban institution. Patients were separated into two cohorts based on whether they underwent primary or revision TJA (rTJA). Outcomes of interest included ED visit within 90-days of surgery, as well as reasons for ED visit and readmission rate. Multivariable logistic regressions were performed to compare the two groups while accounting for all statistically significant demographic variables. RESULTS:Overall, 28,033 patients were included, of whom 24,930 (89%) underwent primary and 3,103 (11%) underwent rTJA. The overall rate of 90-day ED visits was significantly lower for patients who underwent primary TJA in comparison to those who underwent rTJA (3.9% vs 7.0%; p < 0.001). Among those who presented to the ED, the readmission rate was statistically lower for patients who underwent primary TJA compared to rTJA (23.5% vs 32.1%; p < 0.001). CONCLUSION/CONCLUSIONS: 2022;3(7):543-548.

BACKGROUND:Although several techniques and implants have been developed to address bone loss in revision total knee arthroplasty (rTKA), management of these defects remains challenging. This review article discusses the indications and management options of bone loss following total knee arthroplasty based on preoperative workup and intraoperative findings. MAIN TEXT/METHODS:Various imaging modalities are available that can be augmented with intraoperative examination to provide a clear classification of a bony defect. For this reason, the Anderson Orthopaedic Research Institute (AORI) classification is frequently used to guide treatment. The AORI provides a reliable system by which surgeons can classify lesions based on their size and involvement of surrounding structures. AORI type I defects are managed with cement with or without screws as well as impaction bone grafting. For AORI type IIA lesions, wedge or block augmentation is available. For large defects encompassing AORI type IIB and type III defects, bulk allografts, cones, sleeves, and megaprostheses can be used in conjunction with intramedullary stems. CONCLUSIONS:Treatment of bone loss in rTKA continues to evolve as different techniques and approaches have been validated through short- and mid-term follow-up. Extensive preoperative planning with imaging, accurate intraoperative evaluation of the bone loss, and comprehensive understanding of all the implant options available for the bone loss are paramount to success.

INTRODUCTION/BACKGROUND:Surgeons can improve their practice by understanding potentially avoidable reasons for early revision total knee arthroplasty (rTKA). The purpose of this study is to describe potentially avoidable indications for rTKA within 5 years of the index procedure. METHODS:This retrospective observational analysis utilized the rTKA database at a large, academic orthopedic specialty hospital to identify 167 consecutive rTKA from 2014 to 2019 performed within 5 years after primary TKA (pTKA). Two fellowship-trained arthroplasty surgeons reviewed the cases to classify them as potentially avoidable or unavoidable. Unavoidable indications for rTKA included infection/wound complication, arthrofibrosis, instability due to underlying collagen disease or significant weight loss, and any traumatic event leading to pTKA failure. Potentially avoidable indications included atraumatic instability, intraoperative fracture, metal allergy, and atraumatic patellar instability or maltracking. Aseptic loosening was considered avoidable if it occurred in the presence of component malpositioning or poor cementation technique. RESULTS:There were 112 (67.1%) unavoidable cases and 55 avoidable cases (32.9%). Of the unavoidable cases, there were 68 rTKA for infection or wound complications (60.7%), 23 for arthrofibrosis (20.5%), 6 for instability (5.4%), 6 for postoperative fracture (5.4%), 6 for aseptic loosening (5.4%), and 3 for extensor mechanism pathology following trauma (2.6%). Of the potentially avoidable rTKA, 24 were for aseptic loosening (43.7%), 23 for atraumatic instability (41.8%), 6 for atraumatic extensor mechanism pathology (10.9%), 1 for nickel allergy (1.8%), and 1 for intraoperative fracture (1.8%). CONCLUSION/CONCLUSIONS:These findings indicate that over 30% of early rTKA are potentially avoidable. Interventions should focus on addressing potentially avoidable causes such as short-term aseptic loosening and instability to reduce the need for costly and resource-intensive rTKA. Level of evidence III, retrospective observational analysis.

The study aimed to optimize value-based health care practices in total joint arthroplasty (TJA), and we need to understand how the surgical setting can influence efficiency of care. While this has previously been investigated, the purpose of this study was to clarify if these findings are generalizable to an institution with an orthopaedic specialty hospital. A retrospective review was conducted of 6,913 patients who underwent primary or revision total knee arthroplasty (TKA) at one of four hospitals within a single, urban, and academic health system: a high volume academic (HVA) hospital, a low volume academic (LVA) hospital, a high volume community (HVC) hospital, or a low volume community (LVC) hospital. Patient demographics were collected in an arthroplasty database, as were operating room (OR) times and several specific time points during the surgery. The HVA (orthopaedic specialty) hospital had the shortest total primary TKA OR times and the LVC that had the longest times (156.69 vs. 174.68, p < 0.0001). The HVA hospital had the shortest total revision TKA OR times, and the LVC had the longest times (158.20 vs. 184.95, p < 0.0001). In our health system, the HVA orthoapedic specialty hospital had the shortest overall OR time, even when compared with the HVC hospital. This is in contradistinction to prior findings that HVC institutions had the shortest OR times in a health system that did not have an orthopaedic specialty hospital. This provides evidence that an orthopaedic specialty hospital can be a model for efficient care, even at an academic teaching institution.

INTRODUCTION/BACKGROUND:Airborne biologic particles (ABPs) can be measured intraoperatively to evaluate operating room (OR) sterility. Particulate matter (PM) up to 2.5 microns can contain microbial species which may increase infection risk. Our study examines differences in air quality and ABP count in primary (pTKA) and revision total knee arthroplasty (rTKA). METHODS:We analyzed primary and revision TKAs in a single operating room at an academic institution from January 2020 to December 2020. Procedures from March 15, 2020-May 4, 2020 were excluded to avoid COVID-related confounding. Temperature, humidity, and ABP count per minute were recorded with a particle counter intraoperatively and cross-referenced with surgical data from the electronic health records (EHR) using procedure start and end times. Descriptive statistics were used to evaluate differences in variables. P-values were calculated using t-test and chi-square. RESULTS:A total of 107 TKA cases were included: 79(73.8%) pTKAs and 28(26.2%) rTKAs. Time spent in room was significantly higher for rTKAs (primary: 176+46.7 minutes vs. revision: 220+47.1,p<0.0001). Compared to pTKAs, rTKAs had significant percent increases in ABP rates for particles measuring 0.3um(+70.4%,p<0.001), 0.5um(+97.2%,p<0.0001), 1.0um(+53.2%,p=0.001), 2.5um(+30.3%,p=0.017), and for PM 2.5(+108.3%,p<0.001) and PM5.0(+105.6%,p<0.001). CONCLUSION/CONCLUSIONS:RTKAs had significantly longer time spent in room and significant percent increases in ABP rates for particles measuring 0.3um, 0.5um, and 1.0um compared to pTKAs. Measurements of PM2.5 and PM5.0 (which can contain large numbers of microbes) were also significantly greater in rTKAs. Further research is needed to determine whether the size and quantity of ABPs translates to higher infection rates following rTKA.