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Total knee arthroplasty (TKA) is one of the most common procedures in orthopaedics, but there is still debate over the optimal fixation method for long-term durability: cement versus cementless bone ingrowth. Recent improvements in implant materials and technology have offered the possibility of cementless TKA to change clinical practice with durable, stable biological fixation of the implants, improved operative efficiency, and optimal long-term results, particularly in younger and more active patients. This symposium evaluated the history of cementless TKA, the recent resurgence, and appropriate patient selection, as well as the historical and modern-generation outcomes of each implant (tibia, femur, and patella). Additionally, surgical technique pearls to assist in reliable, reproducible outcomes were detailed. Historically, cemented fixation has been the gold standard for TKA. However, cementless fixation is increasing in prevalence in the United States and globally, with equivalent or improved results demonstrated in appropriately selected patients. Cementless TKA provides durable biologic fixation and successful long-term results with improved operating room efficiency. Cementless TKA may be broadly utilized in appropriately selected patients, with intraoperative care taken to perform meticulous bone cuts to promote appropriate bony contact and biologic fixation. [ABSTRACT FROM AUTHOR]

As publishing with open access is becoming increasingly popular within orthopaedics, understanding the types of publishing options available and what each may deliver is critically important. Hybrid articles require a high article processing charge. Open journal articles have a lower fee, while closed license articles are freely accessible at no charge. Open repository articles are peer-reviewed manuscripts posted freely online. The purpose of this study was to determine the relationship between article type and resulting citations, social media attention, and readership in total knee arthroplasty (TKA) literature. Open access TKA journal articles published since 2016 were found using the Altmetric Explorer Database. Data gathered included the Altmetric Attention Score (attention), Mendeley Readership Score (readership), and citations per article. Articles were grouped by type: open journal, hybrid, closed license, and open repository. Results were analyzed using descriptive statistics and Tukey's analysis; α = 0.05. A total of 9,606 publications were included. The open repository had the greatest mean citations (14.40), while open journal (9.55) had fewer than all other categories (P <.001). Hybrid had the greatest mean attention (10.35), and open journal (6.16) had a lower mean attention than all other categories (P ≤.002). Open repository had the greatest mean readership (44.68), and open journal (34.00) had a lower mean readership than all other categories (P ≤.012). The mean publication fee for paid publication options was $1,792 United States dollars. In open access TKA literature, free-to-publish open repositories had the greatest mean citations and readership. Free publication options, open repositories and closed licenses, had greater readership compared to paid publication options. [ABSTRACT FROM AUTHOR]

Preoperative anemia is common in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Several definitions of anemia have been described, with no clear consensus on the optimal one for preoperative screening. We hypothesized that depending on the definition used preoperatively, the proportion of anemic patients identified who would require a postoperative allogeneic blood transfusion would vary significantly. A total of 681,141 patients were identified in a national database who underwent either THA or TKA. Preoperative anemia was classified according to the World Health Organization (WHO) definition, Cleveland Clinic (CC) definition, or race, age, and sex-specific definition described by Beutler et al in 2006. The optimal preoperative (OP) hemoglobin thresholds to predict perioperative transfusions were also calculated using receiver operating characteristic curves. When using the WHO definition, 18% of anemic patients required a transfusion versus 14% (OP definition), 12% (CC definition), and 16% (Beutler definition). Similarly, 0.69% of anemic patients sustained a periprosthetic joint infection within 30 days using the WHO definition versus 0.59% (OP definition), 0.60% (CC definition), or 0.66% (Beutler definition). Using the WHO definition, 5.3% of patients would have sustained a major complication versus 4.5% (OP definition), 4.4% (CC definition), and 5.0% (Beutler definition). Variation in the definition of anemia for preoperative screening in THA and TKA results in substantial differences in discriminative ability to predict perioperative transfusions. The WHO definition identified the largest proportion of patients who ultimately received a perioperative transfusion. [ABSTRACT FROM AUTHOR]

Social media platforms are often used for research dissemination and collaboration. Given the increased prevalence of online-only publications, understanding what drives research dissemination is important. Here, we analyzed factors associated with increased social media attention among peer-reviewed publications in total knee arthroplasty, total hip arthroplasty, and unicompartmental knee arthroplasty. We analyzed publications about total knee arthroplasty, total hip arthroplasty, or unicompartmental knee arthroplasty from 2010 to 2022 using a national database. We analyzed a weighted count of social media mentions, using negative binomial regressions adjusting for days since publication. Publications on "hot topics" in arthroplasty were examined including navigation/robotics, COVID-19, race/ethnicity, body mass index, and reimbursement. There were 9,542 publications included, 4,216 (44%) were open access (OA), 338 (3.5%) included navigation, 32 (0.34%) discussed race/ethnicity, 20 (0.2%) discussed COVID-19, 3,840 (40%) were randomized studies, 30 (0.3%) discussed reimbursement, and 2,867 (30%) were in top-10 orthopaedic journals. Factors associated with higher weighted score included studies about COVID-19 (50 versus 6.0, P <.001), race/ethnicity (15.8 versus 6.0, P <.001), OA status (6.3 versus 5.8, P =.001), and randomized studies (6.5 versus 5.7, P <.001). Studies from top-10 journals had a lower score (5.8 versus 6.2, P =.025), as did studies about body mass index (3.4 versus 6.1, P =.001). Studies about navigation and reimbursement did not have significantly different scores. Studies on COVID-19, race/ethnicity, randomized studies, and OA publication were associated with increased social media while those in top-10 orthopaedic journals had lower scores. Level IV, Prognostic Study. [ABSTRACT FROM AUTHOR]

Open access (OA) publication is growing in total joint arthroplasty literature. While OA manuscripts are free to view, these publications require a fee from authors. This study aimed to compare social media attention and citation rates between OA and non-OA publications in the total knee arthroplasty (TKA) literature. There were 9,606 publications included, with 4,669 (48.61%) as OA articles. The TKA articles were identified from 2016 to 2022. Articles were grouped as OA or non-OA and Altmetric Attention Score (AAS), a weighted count of social media attention, and the Mendeley readership were analyzed using negative binomial regressions while adjusting for days since publication. The OA articles had greater mean AAS (13.45 versus 8.42, P =.012) and Mendeley readership (43.91 versus 36.72, P <.001). OA was not an independent predictor of number of citations when compared to non-OA articles (13.98 versus 13.63, P =.914). Subgroup analysis of studies in the top 10 arthroplasty journals showed OA was not an independent predictor of AAS (13.51 versus 9.53, P =.084) or number of citations (19.51 versus 18.74, P =.495) but was an independent predictor of Mendeley readership (49.05 versus 40.25, P <.003). The OA publications in the TKA literature were associated with increased social media attention, but not overall citations. This association was not observed among the top 10 journals. Authors may use these results to weigh the relative importance of readership, citations, and online engagement to the cost of OA publication. [ABSTRACT FROM AUTHOR]

Background: In January 2018, the Centers for Medicare and Medicaid Services removed total knee arthroplasty (TKA) from the Inpatient Only (IPO) list. This study aimed to compare patient-level payments in TKA cases with a length of stay (LOS) <2 midnights before and after removal of TKA from IPO list.Methods: In this retrospective cohort study, all Medicare patients who received a primary elective TKA from 2016-2019 with a LOS <2 midnights at an academic tertiary center were identified. Total and itemized charges and patient-level payments were compared between eligible TKA cases performed in 2016-2017 and those in 2018-2019. There were 351 eligible TKA cases identified: 151 in 2016-2017 and 200 in 2018-2019.Results: The percentage of patients making any out-of-pocket payment increased in 2018-2019 from 2016-2017 (51.0% versus 10.6%), as did median patient-level payment ($7.30 [range, $0.00-$3,389] versus $0.00 [range, $0.00-$1,248], P < .001 for both). A greater proportion of patients in 2018-2019 paid $1-$50 than in 2016-2017 (37.5% versus 1.3%, P < .001) with no change in the proportion of patients who made payments >$50. Total charges were less in 2018-2019 than in 2016-2017 (P = .001). Charges for drugs, laboratory tests, admissions/floor, and therapies decreased in 2018-2019, whereas charges for the operating room and radiology increased (P < .001 for all).Conclusion: Patients receiving outpatient TKA in 2018-2019 were more likely to have out-of-pocket payments than patients with comparable hospital stay who were designated as inpatients, although most of these payments were less than $50. [ABSTRACT FROM AUTHOR]

Purpose: There are limited prospective data on predictors of patient-reported outcomes (PROs) after whole-breast irradiation (WBI) plus a boost. We sought to characterize longitudinal PROs and cosmesis in a randomized trial comparing conventionally fractionated (CF) versus hypofractionated (HF) WBI.Methods and Materials: From 2011 to 2014, women aged ≥40 years with Tis-T2 N0-N1a M0 breast cancer who underwent a lumpectomy with negative margins were randomized to CF-WBI (50 Gray [Gy]/25 fractions plus boost) versus HF-WBI (42.56 Gy/16 fractions plus boost). At baseline (pre-radiation), at 6 months, and yearly thereafter through 5 years, PROs included the Breast Cancer Treatment Outcome Scale (BCTOS), Functional Assessment of Cancer Therapy-Breast (FACT-B), and Body Image Scale; cosmesis was reported by the treating physician using Radiation Therapy Oncology Group cosmesis values. Multivariable mixed-effects growth curve models evaluated associations of the treatment arm and patient factors with outcomes and tested for relevant interactions with the treatment arm.Results: A total of 287 patients were randomized, completing a total of 14,801 PRO assessments. The median age was 60 years, 37% of patients had a bra cup size ≥D, 44% were obese, and 30% received chemotherapy. Through 5 years, there were no significant differences in PROs or cosmesis by treatment arm. A bra cup size ≥D was associated with worse BCTOS cosmesis (P < .001), BCTOS pain (P = .001), FACT-B Trial Outcome Index (P = .03), FACT-B Emotional Well-being (P = .03), and Body Image Scale (P = .003) scores. Physician-rated cosmesis was worse in patients who were overweight (P = .02) or obese (P < .001). No patient subsets experienced better PROs or cosmesis with CF-WBI.Conclusions: Both CF-WBI and HF-WBI confer similar longitudinal PROs and physician-rated cosmesis through 5 years of follow-up, with no relevant subsets that fared better with CF-WBI. This evidence supports broad adoption of hypofractionation with boost, including in patients receiving chemotherapy and in a population with a high prevalence of obesity. The associations of large breast size and obesity with adverse outcomes across multiple domains highlight the opportunity to engage at-risk patients in lifestyle intervention strategies, as well as to consider alternative radiation treatment regimens. [ABSTRACT FROM AUTHOR]

Background: Falls are associated with morbidity and death in the elderly. The consequences of falls after total joint arthroplasty (TJA) are known, but the consequences of preoperative falls are unclear. We assessed associations between preoperative fall history and hospital readmission rates and discharge disposition after primary TJA.Methods: We queried the National Surgical Quality Improvement Program Geriatric Pilot Project for cases of primary total hip arthroplasty (THA) (n = 3671) and total knee arthroplasty (TKA) (n = 6194) performed between 2014 and 2018 for patients aged ≥65 years. Patient characteristics, comorbidities, functional status indicators, and 30-day outcomes were compared among patients with falls occurring within 3 months, from >3 to 6 months, and from >6 to 12 months before surgery, and patients with no falls in the year before surgery. The timing of falls was assessed for independent associations with hospital readmission and discharge to a skilled care facility (SCF). Alpha = 0.05.Results: Patients who fell within 3 months before surgery had greater odds of SCF discharge (for THA, odds ratio [OR] 2.5, 95% confidence interval [CI] 1.8-3.4; for TKA, OR 1.8, 95% CI 1.4-2.3) and hospital readmission (for THA, OR 1.8, 95% CI 1.1-3.0; for TKA, OR 2.4, 95% CI 1.6-3.5) compared with the no-fall cohort. No such associations were observed for the other two fall cohorts.Conclusion: Falls within 3 months before primary TJA are associated with SCF discharge and readmission for patients aged ≥65 years. Fall history screening should be included in preoperative evaluation.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Background: As the incidence of total joint arthroplasty (TJA) increases, identifying methods for cost reduction is essential. Basic metabolic panels (BMPs) are obtained routinely after TJA. We aimed at assessing the prevalence of intervention secondary to abnormal BMPs after primary TJA and at identifying predictors of the need for postoperative BMPs.Methods: We reviewed 802 cases (758 patients) of primary lower-extremity TJA performed from January 1 through December 31, 2018, at our tertiary care medical center. Patient characteristics, preoperative and postoperative BMPs, comorbidities, current medications, and in-hospital interventions were recorded. Age-adjusted Charlson Comorbidity Index (AA-CCI) values were calculated. Institutional costs of 1 BMP and of all BMPs not prompting intervention were calculated. We used multiple regression to identify independent predictors of in-hospital interventions secondary to abnormal postoperative BMPs.Results: Our institutional BMP cost was $36. A total of 1032 postoperative BMPs were ordered; 958 (93%) prompted no intervention. This equated to $34,488 of avoidable BMP costs. We identified 27 cases (3.4%) requiring intervention secondary to abnormal BMPs. Independent predictors of intervention were preoperative renal dysfunction (ie, abnormal creatinine or glomerular filtration rate <60 mL/min) (odds ratio [OR], 7.8; 95% confidence interval [CI], 2.8-22), number of current nephrotoxic medications (OR, 1.9; 95% CI, 1.3-2.9), and AA-CCI value (OR, 1.2; 95% CI, 1.0-1.5).Conclusion: Routine postoperative BMPs are unwarranted for most patients undergoing primary TJA. Testing may be reserved for those with renal dysfunction, those taking multiple nephrotoxic medications, or those with a high AA-CCI value. [ABSTRACT FROM AUTHOR]

Objectives: Postoperative delirium, associated with negative consequences including longer hospital stays and worse cognitive and physical outcomes, is frequently accompanied by sleep-wake disturbance. Our objective was to evaluate the efficacy and short-term safety of ramelteon, a melatonin receptor agonist, for the prevention of postoperative delirium in older patients undergoing orthopedic surgery.Design: A quadruple-masked randomized placebo-controlled trial (Clinical Trials.gov NCT02324153) conducted from March 2017 to June 2019.Setting: Tertiary academic medical center.Participants: Patients aged 65 years or older, undergoing elective primary or revision hip or knee replacement.Intervention: Ramelteon (8 mg) or placebo MEASUREMENTS: Eighty participants were randomized to an oral gel cap of ramelteon or placebo for 3 consecutive nights starting the night before surgery. Trained research staff conducted delirium assessments for 3 consecutive days starting on postoperative day (POD) 0, after recovery from anesthesia, and on to POD2. A delirium diagnosis was based upon DSM-5 criteria determined by expert panel consensus.Results: Of 80 participants, five withdrew consent (one placebo, four ramelteon) and four were excluded (four ramelteon) after randomization. Delirium incidence during the 2 days following surgery was 7% (5 of 71) with no difference between the ramelteon versus placebo: 9% (3 of 33) and 5% (2 of 38), respectively. The adjusted odds ratio for postoperative delirium as a function of assignment to the ramelteon treatment arm was 1.28 (95% confidence interval: 0.21-7.93; z-value 0.27; p-value = 0.79). Adverse events were similar between the two groups.Conclusion: In older patients undergoing elective primary or revision hip or knee replacement, ramelteon was not efficacious in preventing postoperative delirium. [ABSTRACT FROM AUTHOR]

Background: Nutritional optimization before total joint arthroplasty (TJA) may improve patient outcomes and decrease costs. However, the utility of serologic laboratory markers, including albumin, transferrin, and total lymphocyte count (TLC), as primary indicators of nutrition is unclear. We analyzed the prevalence of abnormal nutritional values before TJA and identified factors associated with them.Methods: We retrospectively reviewed 819 primary cases of TJA performed at 1 institution from January to December 2018. Patient demographic characteristics were assessed for associations with abnormal preoperative nutritional values (albumin <3.5 g/dL, transferrin <200 mg/dL, and TLC <1.5 cells/μL3). Associations of comorbidities, American Society of Anesthesiologists Physical Status classification, and age-adjusted Charlson Comorbidity Index (CCI) with abnormal values were assessed with logistic regression.Results: Values were abnormal for albumin in 21 cases (2.6%), transferrin in 26 cases (5.6%), and TLC in 185 cases (25%). Thirteen cases (1.7%) had abnormal values for 2 markers. Age was associated with abnormal albumin and TLC, and race with abnormal transferrin. Congestive heart failure, chronic kidney disease, pancreatic insufficiency, gastroesophageal reflux disease, osteoporosis, dementia, and CCI were associated with abnormal albumin; Parkinson disease and American Society of Anesthesiologists Physical Status with abnormal transferrin; and dementia, body mass index, cancer history, and CCI with abnormal TLC.Conclusion: We report low prevalence of and a low concordance rate among abnormal nutritional values before primary TJA. Our results suggest that routine testing of all healthy patients is not warranted before TJA. [ABSTRACT FROM AUTHOR]

Background: As the world struggles with the COVID-19 pandemic, health care providers are on the front lines. We highlight the value of engaging in humanitarian medical work, contributions of the hip and knee arthroplasty community to date, and future needs after the resolution of the pandemic. We sought to understand how the arthroplasty community can contribute, based on historical lessons from prior pandemics and recessions, current needs, and projections of the COVID-19 impact.Methods: We polled members of medical mission groups led by arthroplasty surgeons to understand their current efforts in humanitarian medical work. We also polled orthopedic colleagues to understand their role and response. Google Search and PubMed were used to find articles relevant to the current environment of the COVID-19 pandemic, humanitarian needs after previous epidemics, and the economic effects of prior recessions on elective surgery.Results: Hip and knee arthroplasty surgeons are not at the center of the pandemic but are providing an invaluable supportive role through continued care of musculoskeletal patients and unloading of emergency rooms. Others have taken active roles assisting outside of orthopedics. Arthroplasty humanitarian organizations have donated personal protective equipment and helped to prepare their partners in other countries. Previous pandemics and epidemics highlight the need for sustained humanitarian support, particularly in poor countries or those with ongoing conflict and humanitarian crises.Conclusion: There are opportunities now to make a difference in this health care crisis. In the aftermath, there will be a great need for humanitarian work both here and throughout the world. [ABSTRACT FROM AUTHOR]

Background: Current estimates of operative time (OT) for total hip arthroplasty (THA) are reported as the mean OT across all procedures. This method does not reflect variability among surgeons and surgical settings and should not be used to infer individual surgeon work. We hypothesized that this method would underestimate the time it takes individual surgeons to perform THA. Therefore, we compared the mean OT for all THA cases ("overall OT") with the mean OT for individual surgeons ("individual surgeon OT") and examined which factors were associated with each.Methods: Mean OT was calculated for 3972 primary THA cases ("overall OT") by 41 surgeons from 2015 to 2018 in a single health system. The mean OT for each surgeon was determined ("individual surgeon OT"), averaged across surgeons, and compared with overall OT. Overall OT and individual surgeon OT were assessed for associations with surgeon-related (adult reconstruction fellowship training, THA volume, years' experience), hospital-related (hospital type, trainee presence), and patient-related (age, body mass index category, American Society of Anesthesiologists physical status classification) factors (alpha = 0.05).Results: Mean individual surgeon OT was significantly longer (106 ± 21 minutes) than overall OT (96 ± 28 minutes) (P = .03), with 73% of individual surgeon OTs being greater than overall OT. Although all surgeon-, hospital-, and patient-related factors were associated with significant differences in overall OT, only hospital type was associated with differences in individual surgeon OT.Conclusion: Individual surgeon OT was longer than overall OT for most surgeons and provides a better estimate of surgeon work. [ABSTRACT FROM AUTHOR]

Background: Public domain physician review websites (PRWs) and personal websites are extremely popular measures that patients use to evaluate physicians before receiving care. Few studies have examined how orthopedic surgeons are rated on PRWs and personal websites. This study examines the online ratings of hip and knee replacement subspecialists.Methods: The American Association of Hip and Knee Surgeons (AAHKS) fellow's ratings were examined from October 1st, 2018 to December 31st, 2018, on Healthgrades.com, Vitals.com, RateMDs.com, Google.com, and personal websites. Number of responses and average ratings (0.0-5.0) were recorded, along with provider gender, years in practice (0-10, 11-20, and 21+), practice type (academic, private), geographic region (NE, SE, MW, SW, W), degree (MD, DO), and fellowship training (yes, no). The Kruskal-Wallis testing was performed to determine factors affecting positive surgeon ratings.Results: 98.3% (483) of 490 AAHKS surgeons were rated at least once. No significant differences in average ratings were identified between websites. Surgeons in practice 1-10 years had significantly higher ratings than those in practice 11-20 and 21+ years (P < .01). Fellowship-trained surgeons in practice 1-10 years also showed significantly higher ratings. No differences in average ratings were found between gender, practice type, and geographic region.Conclusions: AAHKS surgeons have high average ratings and are rated online frequently. Surgeons in practice 1-10 years had statistically higher overall average ratings. Adult reconstruction fellowship training was also associated with higher average ratings for surgeons in practice 1-10 years. Public domain PRWs and personal websites showed no difference in average ratings. [ABSTRACT FROM AUTHOR]

Background: High-quality care is essential in total joint arthroplasty. Multiple initiatives such as centers of excellence, patient optimization, and alternative payment models have demonstrated improved outcomes and decreased cost. Many studies have shown that longer operative times (OTs) are associated with increased frequency of postoperative complications. These findings often come from large data sets and may not accurately represent the average OT of individual surgeons. The purpose of this study was to determine the hospital and patient-related factors that influence OT.Methods: This retrospective study reviewed OT of 6003 total knee arthroplasty cases performed by 41 surgeons at 4 hospitals in a single health-care system. Mean OT was calculated for each surgeon. The effect of surgeon, hospital-, and patient-related factors on OT was assessed.Results: Among the 41 surgeons, the mean OT was 105 ± 25 minutes. Two community hospitals had significantly faster OT compared with the tertiary care academic hospital. Surgeons' OT for morbidly obese patients was significantly longer compared with normal, overweight, and obese patients. Surgeon volume, surgeon experience, trainee presence, and American Society of Anesthesiologists status did not significantly affect surgical time.Conclusions: Operative time was influenced by hospital-related (tertiary, community) and patient-related (morbid obesity vs lower body mass index groups) factors. However, specific surgeon factors (surgical volume, experience), surgical team factors (presence or absence of trainee), and patient factors (American Society of Anesthesiologists status) did not significantly alter the OT. Additional studies of larger health systems are needed to examine additional patient, surgeon, and hospital factors which may influence the OT. [ABSTRACT FROM AUTHOR]

Body mass index (BMI) impacts risk for revision total knee arthroplasty (rTKA), but the relationship between BMI and cause for revision remains unclear. We hypothesized that patients in different BMI classes would have disparate risk for causes of rTKA. There were 171,856 patients who underwent rTKA from 2006 to 2020 from a national database. Patients were classified as underweight (BMI < 19), normal-weight, overweight/obese (BMI 25 to 39.9), or morbidly obese (BMI > 40). Multivariable logistic regressions adjusted for age, sex, race/ethnicity, socioeconomic status, payer status, hospital geographic setting, and comorbidities were used to examine the effect of BMI on risk for different rTKA causes. Compared to normal-weight controls, underweight patients were 62% less likely to undergo revision due to aseptic loosening, 40% less likely due to mechanical complications, 187% more likely due to periprosthetic fracture, 135% more likely due to periprosthetic joint infection (PJI). Overweight/obese patients were 25% more likely to undergo revision due to aseptic loosening, 9% more likely due to mechanical complications, 17% less likely due to periprosthetic fracture, and 24% less likely due to PJI. Morbidly obese patients were 20% more likely to undergo revision due to aseptic loosening, 5% more likely due to mechanical complications, and 6% less likely due to PJI. Mechanical reasons were more likely to be the cause of rTKA in overweight/obese and morbidly obese patients, compared to underweight patients, for whom revision was more likely to be infection or fracture related. Increased awareness of these differences may promote patient-specific management to reduce complications. III. [ABSTRACT FROM AUTHOR]

Posterior-stabilized (PS) and cruciate-retaining (CR) have been the most common tibial designs used in total knee arthroplasty. Ultra-congruent (UC) inserts are becoming popular because they preserve bone without relying on the posterior cruciate ligament balance and integrity. Despite increasing use, there is no consensus on how UC inserts perform versus PS and CR designs. A comprehensive literature search of 5 online databases was performed for articles from January 2000 to July 2022 comparing the kinematic and clinical outcomes of PS or CR tibial inserts to UC inserts. There were nineteen studies included. There were 5 studies comparing UC to CR and 14 comparing UC to PS. Only one randomized controlled trial (RCT) was rated "good quality". For CR studies, pooled analyses showed no difference in knee flexion (n = 3, P =.33) or Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores (n = 2, P =.58). For PS studies, meta-analyses showed better anteroposterior stability (n = 4, P <.001) and more femoral rollback (n = 2, P <.001) for PS but no difference in knee flexion (n = 9, P =.55) or medio-lateral stability (n = 2, P =.50). There was no difference with WOMAC (n = 5, P =.26), Knee Society Score (n = 3, P =.58), Knee Society Knee Score (n = 4, P =.76), or Knee Society Function Score (n = 5, P =.51). Available data demonstrates there are no clinical differences between CR or PS and UC inserts in small short-term studies ending around 2 years after surgery. More importantly, high-quality research comparing all inserts is lacking, demonstrating a need for more uniform and longer-term studies beyond 5 years after surgery to justify increased UC usage. [ABSTRACT FROM AUTHOR]

Purpose: Hypsarrhythmia is the interictal EEG pattern most often associated with infantile spasms. We set out to evaluate the metabolic impact of hypsarrhythmia among patients with infantile spasms by contrasting regional cerebral metabolic activity among children with and without hypsarrhythmia.Methods: Patients with video-EEG confirmed infantile spasms who underwent simultaneous interictal EEG and FDG-PET as part of a surgical evaluation were retrospectively identified. Pons-normalized relative cerebral metabolic activity (RCA) was ascertained in 18 cortical and 6 subcortical pre-specified regions of interest (ROIs).Results: We identified 63 patients with infantile spasms who underwent simultaneous EEG/PET, including children with hypsarrhythmia (n = 9), high-voltage EEG background (n = 20), and multifocal independent spike discharges (MISD) (n = 34). Among them, a putative epileptogenic zone was identified within the left-hemisphere only (n = 27), right-hemisphere only (n = 20), or assumed to be bilateral (n = 16). After adjustment for age at PET, the presence of hypsarrhythmia was associated with hypermetabolism in 11 of 18 cortical ROI's. After adjustment for lateralized epileptogenic zones, the association between hypsarrhythmia and hypermetabolism was generally stronger within the left hemisphere.Conclusion: Hypsarrhythmia is associated with widespread-and curiously left more than right-elevations in pons-normalized RCA, which is not evident on routine clinical review of individual PET studies. This study suggests that hypsarrhythmia may be a quasi-ictal phenomenon based on widespread and usually bilateral cortical hypermetabolism. [ABSTRACT FROM AUTHOR]

NADH-dependent reduced ferredoxin:NADP oxidoreductase (NfnAB) is found in the cytoplasm of various anaerobic bacteria and archaea. The enzyme reversibly catalyzes the endergonic reduction of ferredoxin with NADPH driven by the exergonic transhydrogenation from NADPH onto NAD+. Coupling is most probably accomplished via the mechanism of flavin- based electron bifurcation. To understand this process on a structural basis, we heterologously produced the NfnAB complex of Thermotoga maritima in Escherichia coli, provided kinetic evidence for its bifurcating behavior, and determined its x-ray structure in the absence and presence of NADH. The structure of NfnAB reveals an electron transfer route including the FAD (a-FAD), the [2Fe-2S] cluster of NfnA and the FAD (b-FAD), and the two [4Fe-4S] clusters of NfnB. Ferredoxin is presumably docked onto NfnB close to the [4Fe-4S] cluster distal to b-FAD. NAD(H) binds to a-FAD and NADP(H) consequently to b-FAD, which is positioned in the center of the NfnAB complex and the site of electron bifurcation. Arg187 is hydrogen-bonded to N5 and O4 of the bifurcating b-FAD and might play a key role in adjusting a low redox potential of the FADH?/FAD pair required for ferredoxin reduction. A mechanism of FAD-coupled electron bifurcation by NfnAB is proposed. [ABSTRACT FROM AUTHOR]

Congenital talipes equinovarus (CTEV), more commonly known as clubfoot, is a deformity of the foot that is not well understood. The tarsal navicular is at the center of the disease process and exhibits abnormal development and delayed ossification. However, its role in the pathologic process is not clear. The aim of the present study was to better understand the role of the tarsal navicular in CTEV by correlating the presence of the navicular ossification center and relapse of clubfoot deformity after surgical treatment. The medical records and radiographs of 34 patients (41 feet) with surgically treated CTEV were reviewed for the presence of the navicular ossification center and the lateral talocalcaneal angles. Of the 41 feet, 17 (41.46%) did not have the tarsal navicular ossification center present before surgery, and 24 (58.54%) did have the ossification center present. The talocalcaneal angles were similar between those with and without the navicular ossification center present. No significant difference was found in the incidence of relapse between the nonossified navicular group (17.6%) and the ossified navicular group (16.7%; p = .63). The presence of the navicular ossification center before surgery does not appear to have prognostic value for the relapse of CTEV after surgical intervention. [ABSTRACT FROM AUTHOR]

Abstract: Phytochemical studies on the methanolic extract of Drypetes gossweileri afforded N-β-d-glucopyranosyl-p-hydroxyphenylacetamide (1), p-hydroxyphenylacetic acid (2), p-hydroxyphenyl-acetonitrile (3), p-hydroxyacetophenone (4), 3,4,5-trimethoxyphenol (5), dolichandroside A (6), and β-amyrone (7). Compounds 1–7 were identified with the aid of extensive NMR and MS spectroscopic studies. Compound 1 was a new natural product and was isolated for the first time from plant containing N-glucose moiety incorporated in its structure. Compounds 1–7 exhibited moderate to the weak source anti-α-glucosidase inhibitory activity. Compound 7 exhibited moderate anti-acetylcholinesterase (AChE) activity while the rest of the isolates were weakly active in this bioassay. Compounds 1–7 also showed moderate anti-fungal activity. [Copyright &y& Elsevier]

Indices based on network theory are often used to describe food web functioning. These indices take as input food web flows that are estimated based on merging of (scarce) data with linear inverse methods (LIMs). Due to under sampling, most food webs are highly uncertain and can only be quantified within a specific uncertainty range. The linear inverse method (LIM) can estimate food web flows using a variety of techniques, e.g. the parsimonious or minimum norm (MN) solution, which selects one food web, based on a quadratic minimization technique or the Monte Carlo solution where a finitely many random solutions are generated which are then averaged. We use the Monte Carlo approach (MCA) to estimate the values of several indices from four published food webs, the Gulf of Riga for the autumn, summer and spring seasons, and the Takapoto atoll system. We first show that network indices are much better constrained than the uncertain food webs from which they are calculated. Therefore, even in the face of food web uncertainty, they are robust estimators of food web functioning. We then use the MCA-derived network indices to generate cumulative density functions for each index. These serve to compute the probabilities of the MN indices estimates being an extreme solution as compared to the median values. Our findings show that 82% of the MN solutions are smaller than the MCA solutions, and 63% of the network indices are significantly under-estimated. [Copyright &y& Elsevier]

Abstract: Pigmented villonodular synovitis is a benign, proliferative disorder of unknown etiology that mainly affects the synovium of the joint, bursa, and the tendon sheath. The most common joint affected is the knee. Pigmented villonodular synovitis presents in either of 2 distinct forms, localized or diffuse. In this report, we describe a case of diffuse pigmented villonodular synovitis that presented in the knee 18 months after total knee arthroplasty. The diagnosis was suggested by histologic analysis of bloody aspirate and by abnormal synovial proliferation noted at arthroscopy and confirmed by histologic analysis of the resected tissue. [Copyright &y& Elsevier]

Electron bifurcation is a fundamental strategy of energy coupling originally discovered in the Q-cycle of many organisms. Recently a flavin-based electron bifurcation has been detected in anaerobes, first in clostridia and later in acetogens and methanogens. It enables anaerobic bacteria and archaea to reduce the low-potential [4Fe-4S] clusters of ferredoxin, which increases the efficiency of the substrate level and electron transport phosphorylations. Here we characterize the bifurcating electron transferring flavoprotein (EtfAf) and butyryl-CoA dehydrogenase (BcdAf) of Acidaminococcus fermentans, which couple the exergonic reduction of crotonyl-CoA to butyryl-CoA to the endergonic reduction of ferredoxin both with NADH. EtfAf contains one FAD (α-FAD) in subunit α and a second FAD (β-FAD) in subunit β. The distance between the two isoalloxazine rings is 18 Å. The EtfAf-NAD+ complex structure revealed β-FAD as acceptor of the hydride of NADH. The formed β-FADH- is considered as the bifurcating electron donor. As a result of a domain movement, α-FAD is able to approach β-FADH- by about 4 Å and to take up one electron yielding a stable anionic semiquinone, α-FAD-, which donates this electron further to Dh-FAD of BcdAf after a second domain movement. The remaining non-stabilized neutral semiquinone, β-FADH•, immediately reduces ferredoxin. Repetition of this process affords a second reduced ferredoxin and Dh-FADH- that converts crotonyl-CoA to butyryl-CoA. [ABSTRACT FROM AUTHOR]

Introduction: Acute myocardial infarction (AMI) is a common cause of death following hip fracture surgery. This study aimed to determine the incidence and timing of perioperative AMI treated with percutaneous coronary intervention (PCI) in hip fracture patients, and to compare in-hospital mortality and complications between hip fracture patients who did not have an AMI, those who sustained a perioperative AMI and did not undergo PCI, and those who sustained an AMI and underwent PCI.Methods: The National Inpatient Sample (NIS) was queried from 2010 through the third quarter of 2015 to identify all patients undergoing hip fracture surgery. Patients were stratified into three cohorts: perioperative AMI but no PCI (no PCI cohort), perioperative AMI with PCI (PCI cohort), and no perioperative AMI or PCI (no AMI cohort). Patient demographics, comorbidities, in-hospital mortality, and complications were compared between cohorts. Multivariable logistic regression adjusting for age, sex, procedure, and Elixhauser score was used to assess the relative odds of in-hospital mortality for each cohort.Results: A total of 1,535,917 hip fracture cases were identified, with 1.9% in the no PCI cohort, 0.01% in the PCI cohort, and 98.0% in the no AMI cohort. In-hospital mortality was lower in the PCI cohort than in the no PCI cohort (8.8% vs. 14%), and was greater for both than in the no AMI cohort (1.6%, p < 0.001 for all). Both the no PCI cohort (OR, 6.1; 95% CI, 5.6-6.6) and PCI cohort (OR, 4.1; 95% CI, 2.8-6.0) had increased adjusted odds of in-hospital mortality compared to the no AMI cohort. The PCI cohort had a higher rate of bleeding complications than both other cohorts, and the no PCI cohort had a higher rate of transfusion than both other cohorts.Conclusions: Perioperative AMI both with and without PCI independently increases the risk of mortality in hip fracture patients, with the highest risk of mortality in those with AMI without PCI. Providers should understand the increased morbidity and mortality associated with AMI in hip fracture patients, as well as the risks and benefits of perioperative PCI, in order to better counsel and manage these patients.Level Of Evidence: III. [ABSTRACT FROM AUTHOR]

Compare outcomes for patients with recently diagnosed COVID-19 infection to those without COVID-19 infection undergoing operative treatment of hip fractures using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. Retrospective propensity score matched cohort. Patients who received surgery for an acute hip fracture (intramedullary nail (IMN), open reduction internal fixation (ORIF) or hemiarthroplasty) in 2021 were identified from the NSQIP database. Propensity score matching was implemented using patient demographics and preoperative medical conditions to compare outcomes for COVID-19-positive and COVID-19-negative cohorts. After matching, COVID-19-positive patients exhibited a higher risk of 30-day mortality (Odds ratio (OR) 1.48, 95 % confidence interval (CI) 1.01 – 2.04), pneumonia (OR 2.90, 95 % CI: 1.91 – 4.33), unplanned intubation (OR 2.53, 95 % CI: 1.39 – 4.39), and septic shock (OR 2.51, 95 % CI: 1.10 – 4.67). COVID-19-positive patients were also more likely to have a longer length of hospital stay (Hazard Ratio 1.3, 95 % CI: 1.20 – 1.41) and were more likely to be discharged to an acute care hospital (OR 1.90, 95 % CI: 1.03 – 3.06). Active COVID-19 infection is an independent risk factor for complications as well as increased resource utilization in patients undergoing surgical treatment of acute hip fracture. Using the results of this multicenter study, quantification of these risks can help inform practice and treatment protocols for this population. III. [ABSTRACT FROM AUTHOR]