Bt corn and cotton planting may benefit peanut growers by reducing aflatoxin risk.

Decades of studies have shown that Bt corn, by reducing insect damage, has lower levels of mycotoxins (fungal toxins), such as aflatoxin and fumonisin, than conventional corn. We used crop insurance data to infer that this benefit from Bt crops extends to reducing aflatoxin risk in peanuts: a non-Bt crop. In consequence, we suggest that any benefit-cost assessment of how transgenic Bt crops affect food safety should not be limited to assessing those crops alone; because the insect pest control offered by Bt crops affects the food safety profile of other crops grown nearby. Specifically, we found that higher Bt corn and Bt cotton planting rates in peanut-growing areas of the United States were associated with lower aflatoxin risk in peanuts as measured by aflatoxin-related insurance claims filed by peanut growers. Drought-related insurance claims were also lower: possibly due to Bt crops' suppression of insects that would otherwise feed on roots, rendering peanut plants more vulnerable to drought. These findings have implications for countries worldwide where policies allow Bt cotton but not Bt food crops to be grown: simply planting a Bt crop may reduce aflatoxin and drought stress in nearby food crops, resulting in a safer food supply through an inter-crop "halo effect."

Intraoperative physician assessment during total hip arthroplasty correlates with DXA parameters.

PURPOSE: Orthopedic surgeons can assess bone status intraoperatively and recommend skeletal health evaluation for patients with poor bone quality. Intraoperative physician assessment (IPA) at the time of total knee arthroplasty correlates with preoperative DXA-measured bone mineral density (BMD). This study evaluated IPA during total hip arthroplasty (THA) as a quantitative measure of bone status based on tactile assessment. METHODS: This retrospective analysis identified 60 patients (64 hips) undergoing primary THA who had IPA recorded in the operative report and a DXA within 2 years before surgery. Intraoperatively, two surgeons assessed bone quality on a 5-point scale (1 = excellent; 5 = poor). IPA score was compared to DXA BMD and T-score, 3D Shaper measurements, WHO classification, FRAX scores, radiographic Dorr classification, and cortical index. RESULTS: There was a strong correlation between the IPA score and lowest T-score, WHO classification, and FRAX major and hip fracture scores (r = ± 0.485-0.622, all p < 0.001). There was a moderate correlation between IPA score and total hip BMD and 3D Shaper measurements, including trabecular volumetric BMD, cortical surface BMD, and cortical thickness (r = ± 0.326-0.386, all p < 0.01). All patients with below-average IPA scores had osteopenia or osteoporosis by DXA. CONCLUSION: IPA during THA is a simple, valuable tool for quantifying bone status based on tactile feedback. This information can be used to identify patients with poor bone quality that may benefit from skeletal status evaluation and treatment and provide intraoperative guidance for implant selection. Orthopedic surgeons can assess bone health at the time of surgery. Intraoperative physician assessment (IPA) is a bone quality score based on surgeons' tactile assessment that correlates strongly with the lowest T-score, WHO classification, and FRAX fracture risk. IPA can guide surgical decision-making and future bone health treatment.

Environmental and economic concerns surrounding restrictions on glyphosate use in corn.

Since the commercialization of transgenic glyphosate-tolerant (GT) crops in the mid-1990s, glyphosate has become the dominant herbicide to control weeds in corn, soybean, and other crops in the United States and elsewhere. However, recent public concerns over its potential carcinogenicity in humans have generated calls for glyphosate-restricting policies. Should a policy to restrict glyphosate use, such as a glyphosate tax, be implemented? The decision involves two types of tradeoffs: human health and environmental (HH-E) impacts versus market economic impacts, and the use of glyphosate versus alternative herbicides, where the alternatives potentially have more serious adverse HH-E effects. Accounting for farmers' weed management choices, we provide empirical evaluation of the HH-E welfare and market economic welfare effects of a glyphosate use restriction policy on US corn production. Under a glyphosate tax, farmers would substitute glyphosate for a combination of other herbicides. Should a 10% glyphosate tax be imposed, then the most conservative welfare estimate is a net HH-E welfare gain with a monetized value of US$6 million per annum but also a net market economic loss of US$98 million per annum in the United States, which translates into a net loss in social welfare. This result of overall welfare loss is robust to a wide range of tax rates considered, from 10 to 50%, and to multiple scenarios of glyphosate's HH-E effects, which are the primary sources of uncertainties about glyphosate's effects.

Mode of Fixation and Survivorship in Primary Total Knee Arthroplasty in the American Joint Replacement Registry.

BACKGROUND: A recent rapid increase in cementless total knee arthroplasty (TKA) has been noted in the American Joint Replacement Registry (AJRR). The purpose of our study was to compare TKA survivorship based on the mode of fixation reported to the AJRR in the Medicare population. METHODS: Primary TKAs from Medicare patients submitted to AJRR from 2012 to 2022 were analyzed. The Medicare and AJRR databases were merged. Cox regression stratified by sex compared revision outcomes (all-cause, infection, mechanical loosening, and fracture) for cemented, cementless, and hybrid fixation, controlling for age and the Charlson comorbidity index (CCI). RESULTS: A total of 634,470 primary TKAs were analyzed. Cementless TKAs were younger (71.8 versus 73.1 years, P < .001) than cemented TKAs and more frequently utilized in men (8.2 versus 5.8% women, P < .001). Regional differences were noted, with cementless fixation more common in the Northeast (10.5%) and South (9.2%) compared to the West (4.4%) and Midwest (4.3%) (P < .001). No significant differences were identified in all-cause revision rates in men or women ≥ 65 for cemented, cementless, or hybrid TKA after adjusting for age and CCI. Significantly lower revision for fracture was identified for cemented compared to cementless and hybrid fixation in women ≥ 65 after adjusting for age and CCI (P = .0169). CONCLUSIONS: No survivorship advantage for all-cause revision was noted based on the mode of fixation in men or women ≥ 65 after adjusting for age and CCI. A significantly lower revision rate for fractures was noted in women ≥ 65 utilizing cemented fixation. Cementless fixation in primary TKA should be used with caution in elderly women.

Intraoperative physician assessment of bone: correlation to bone mineral density.

This study evaluated the intraoperative physician assessment (IPA) of bone status at time of total knee arthroplasty. IPA was highly correlated with distal femur and overall bone mineral density. When IPA identifies poor bone status, formal bone health assessment is indicated. PURPOSE: Intuitively, intraoperative physician assessment (IPA) would be an excellent measure of bone status gained through haptic feedback during bone preparation. However, no studies have evaluated the orthopedic surgeon's ability to do so. This study's purpose, in patients undergoing total knee arthroplasty (TKA), was to relate IPA with (1) the lowest bone mineral density (BMD) T-score at routine clinical sites; and (2) with distal femur BMD. METHODS: Seventy patients undergoing TKA by 3 surgeons received pre-operative DXA. Intraoperatively, bone quality was assessed on a 5-point scale (1 excellent to 5 poor) based on tactile feedback to preparation. Demographic data, DXA results, and IPA score between surgeons were compared by factorial ANOVA. Lowest T-score and distal femur BMD were associated with IPA using Spearman's correlation. RESULTS: The mean (SD) age and BMI were 65.8 (7.6) years and 31.4 (5.1) kg/m2, respectively. Patient demographic data, BMD, and IPA (mean [SD] = 2.74 [1.2]) did not differ between surgeons. IPA correlated with the lowest T-score (R = 0.511) and distal femur BMD (R = 0.603-0.661). Based on the lowest T-score, no osteoporotic patients had an IPA above average, and none with normal BMD was classified as having poor bone. CONCLUSIONS: IPA is highly correlated with local (distal femur) and overall BMD. This study supports the International Society for Clinical Densitometry position that surgeon concern regarding bone quality should lead to bone health assessment. As IPA is comparable between surgeons, it is logical this can be widely applied by experienced orthopedic surgeons. Future studies evaluating IPA at other anatomic sites are indicated.

Proposed bone health screening protocol to identify total knee arthroplasty patients for preoperative DXA.

This study evaluates a novel, simple bone health screening protocol composed of patient sex, age, fracture history, and FRAX risk to identify total knee arthroplasty patients for preoperative DXA. Findings supported effectiveness, with sensitivity of 1.00 (CI 0.92-1.00) and specificity of 0.54 (CI 0.41-0.68) when evaluating for clinical osteoporosis. PURPOSE: Bone health optimization is a process where osteoporotic patients are identified, evaluated via modalities such as dual-energy X-ray absorptiometry (DXA), and treated when indicated. There are currently no established guidelines to determine who needs presurgical DXA. This study evaluates the effectiveness of a simple screening protocol to identify TKA patients for preoperative DXA. METHODS: This prospective cohort study began on September 1, 2019, and included 100 elective TKA patients. Inclusion criteria were ≥ 50 years and primary TKA. All patients obtained routine clinical DXA. The screening protocol defining who should obtain DXA included meeting any of the following: female ≥ 65, male ≥ 70, fracture history after age 50, or FRAX major osteoporotic fracture risk without bone mineral density (BMD) adjustments ≥ 8.4%. Osteoporosis was defined by the World Health Organization (WHO) criteria (T-score ≤ - 2.5) or clinically (T-score ≤ - 2.5, elevated BMD-adjusted FRAX risk, or prior hip/spine fracture). Sensitivity and specificity were calculated. RESULTS: The study included 68 females and 32 males, mean age 67.2 ± 7.7. T-score osteoporosis was observed in 16 patients while 43 had clinical osteoporosis. Screening criteria recommending DXA was met by 69 patients. Screening sensitivity was 1.00 (CI 0.79-1.00) and specificity was 0.37 (CI 0.27-0.48) for identifying patients with T-score osteoporosis. Similar sensitivity of 1.00 (CI 0.92-1.00) and specificity of 0.54 (CI 0.41-0.68) were found for clinical osteoporosis. CONCLUSIONS: A simple screening protocol identifies TKA patients with T-score and clinical osteoporosis for preoperative DXA with high sensitivity in this prospective cohort study.

Assessment of the added value of intravenous gadolinium for knee osteosarcoma resection planning in pediatric and young adult patients.

BACKGROUND AND OBJECTIVES: To assess the impact of Gadolinium-enhanced magnetic resonance imaging (MRI) sequences on Preoperative imaging evaluation and surgical planning parameters for osteosarcoma (OS) of the knee in pediatric and young adult patients. METHODS: Thirty MRI scans of patients with OS about the knee were reviewed by five orthopedic oncologists. Key preoperative parameters (neurovascular bundle involvement, intra-articular tumor extension, extent of intramedullary extension) and surgical plans were evaluated based on non-contrast versus Gd contrast enhanced sequences. Assessment agreement, inter-rater agreement, and intrarater agreement between pre and postcontrast images were evaluated via Kappa statistics. RESULTS: Moderate agreement was seen between non and contrast-enhanced assessment of neurovascular involvement and intra-articular tumor extension. Intrarater reproducibility was substantial for neurovascular bundle involvement (precontrast Kappa: 0.63, postcontrast Kappa: 0.69). Intrarater reproducibility was also substantial for precontrast (Kappa: 0.70) and moderate for postcontrast (Kappa: 0.50) assessment of intra-articular tumor extension. Planned resection length and choice of surgical approach were similar between sequences. The addition of Gd-enhanced sequences improved the inter-rater agreement across collected parameters. CONCLUSIONS: While some findings suggest that contrast enhanced sequences may not significantly alter the assessment of key preoperative planning parameters by orthopedic oncologists, they may help reduce variability among providers with differing experience levels.

Femur and Tibia BMD Measurement in Elective Total Knee Arthroplasty Candidates.

Distal femur BMD declines ∼20% following total knee arthroplasty (TKA) potentially leading to adverse outcomes. BMD knowledge before and following TKA might allow interventions to optimize outcomes. We hypothesized that distal femur and proximal tibial BMD could be reproducibly measured with existing DXA technology. Elective TKA candidates were enrolled and standard clinical DXA plus bilateral PA and lateral knee scans acquired. Manual regions of interest (ROIs) were placed at distal femur and proximal tibia sites based on required TKA machining and periprosthetic fracture location. Intra- and inter-rater BMD reliability was assessed by intra-class correlation (ICC). Custom and standard proximal femur BMD were correlated by linear regression and paired t test evaluated BMD differences between planned surgical and contralateral side. One hundred subjects (68F/32M), mean (SD) age and BMI of 67.2 (7.7) yr and 30.8 (4.8) kg/m2 were enrolled. Lowest clinical BMD T-score was < -1.0 in 65% and ≤ -2.5 in 16%; 34 had prior fracture. BMD reproducibility at all custom ROIs was excellent; ICC > 0.96. Mean BMD at custom ROIs ranged from 0.903 to 1.346 g/cm2 in the PA projection and 0.891 to 1.429 g/cm2 in the lateral. Lower BMD values were observed at the proximal tibia, while the higher measurements were at the femur condyle. Custom knee ROI BMD was highly correlated (p < 0.0001) with total and femur neck with better correlation at ROIs adjacent to the joint (R2 = 0.62-0.67, 0.49-0.55 respectively). In those without prior TKA (n = 76), mean BMD was lower (2.8%-6.6%; p < 0.05) in the planned surgical leg at all custom ROIs except the PA tibial regions. Individual variability was present with 82% having a custom ROI with lower BMD (up to 53%) in the planned operative leg. Distal femur and proximal tibial BMD can be measured using custom ROIs with good reproducibility. Suboptimal bone status is common in TKA candidates and distal femur/proximal tibia BMD is often lower on the planned operative side. Routine distal femur/proximal tibial BMD measurement might assist pre-operative interventions, surgical decision-making, subsequent care and outcomes. Studies to evaluate these possibilities are indicated.

Challenges for rotational grazing practice: Views from non-adopters across the Great Plains, USA.

Many ranchers who practice rotational grazing have experienced economic and ecological benefits. However, the adoption rate of rotational grazing has stagnated. To identify major challenges faced by non-adopters of rotational grazing as well as factors that affect the perceptions about different challenges, we conducted a mail survey of 4250 eligible ranchers in North Dakota, South Dakota and Texas, USA. Key categories of information obtained included basic ranch information, rotational grazing adoption status, and related information. Among 875 respondents, 40.4% identified themselves as non-adopters and perceived labor and water source constraints as the two major challenges, followed by high initial investment costs. This indicates the need for technical support and educational programs to address producers' concerns in addition to the monetary support from government subsidy programs. Findings from logistic regression analyses further indicate that landowners with higher quality soil, relatively more grassland (in both acres and percentage) and more owned land, generally perceive lower barriers to choosing rotational grazing practices and, therefore, may be a suitable target group for more effective outreach efforts and public fund investments to enhance the adoption of beneficial rotational grazing practices.

Insecticides, more than herbicides, land use, and climate, are associated with declines in butterfly species richness and abundance in the American Midwest.

Mounting evidence shows overall insect abundances are in decline globally. Habitat loss, climate change, and pesticides have all been implicated, but their relative effects have never been evaluated in a comprehensive large-scale study. We harmonized 17 years of land use, climate, multiple classes of pesticides, and butterfly survey data across 81 counties in five states in the US Midwest. We find community-wide declines in total butterfly abundance and species richness to be most strongly associated with insecticides in general, and for butterfly species richness the use of neonicotinoid-treated seeds in particular. This included the abundance of the migratory monarch (Danaus plexippus), whose decline is the focus of intensive debate and public concern. Insect declines cannot be understood without comprehensive data on all putative drivers, and the 2015 cessation of neonicotinoid data releases in the US will impede future research.

Durability of a cruciate-retaining TKA with modular tibial trays at 20 years.

BACKGROUND: Modular tibial trays have been utilized in TKA for more than 20 years. However, concerns have been raised about modular implants and it is unclear whether these devices are durable in the long term. QUESTIONS/PURPOSES: We determined (1) survival, (2) relationship of age and polyethylene thickness with revision, (3) function, and (4) radiographic lucencies and osteolysis in patients having a single TKA implant at 20-year followup. METHODS: We prospectively followed 75 patients implanted with 101 Press-Fit Condylar(®) (Johnson and Johnson Professional, Inc, Raynham, MA, USA) posterior cruciate-retaining TKAs (with modular tibial trays) between 1988 and 1991. At 20 years, 59 patients were deceased. We clinically evaluated the living 16 patients (22 knees) and contacted the relatives of all deceased patients to confirm implant status. We clinically assessed 14 of the 16 patients with the Knee Society score, WOMAC, and UCLA and Tegner activity level scores. Radiographically, we determined lucencies, component migration, and osteolysis. We performed survival analysis including all original patients. Minimum followup was 20 years (mean, 20.6 years; range, 20-21.8 years). RESULTS: Six reoperations were performed in five patients (6% rate of revision) over the 20-year followup. All revisions were related to polyethylene wear and occurred at least 10 years after the primary procedure. Survivorship with revision for any reason as the end point was 91% (95% CI, 0.83-0.97) at 20 years. Average Knee Society clinical and functional scores were 90 (range, 60-100) and 59 (range, 30-87), respectively. CONCLUSIONS: Our data demonstrate the durability of this posterior cruciate-retaining TKA design. The data provide a standard for newer designs and newer bearing surface materials at comparable followup.

Determinants of farms' antibiotic consumption - A longitudinal study of pig fattening farms in Germany.

As high consumption of antibiotics in livestock production poses risks to public health, Germany has implemented a monitoring system to decrease their administration to farm animals. Data from 1,984 German pig farms are used to describe prescription trends for different antibiotic subclasses between Autumn 2017 and Autumn 2019. A panel Tobit model with control function approach is implemented to identify determinants of antibiotic consumption, where variables studied include farm, farmer, and county characteristics as well as weather variables. The overall quantity of prescribed antibiotics has been stable but with seasonal fluctuations and a shift away from critically important antibiotics used. Biosecurity factors such as livestock farm density in a county and pigs per farm are shown to be important drivers of antibiotic consumption. In addition, the number of cold days within a season increases antibiotic consumption but precipitation and the number of hot days have no significant effect.

Health burden associated with tillage-related PM2.5 pollution in the United States, and mitigation strategies.

Exposure to airborne particulate matter of diameter less than 2.5 µm (PM2.5) is associated with cardiovascular diseases (CVD) and chronic obstructive pulmonary disease (COPD). In agriculture, the practice of tilling generates PM2.5 emissions that can jeopardize human health. This paper estimates the annual deaths and disability-adjusted life years (DALYs) from CVD and COPD attributable to PM2.5 emissions from corn, soybean, cotton, and wheat tillage in the contiguous United States. Primary PM2.5 from crop-tillage combination was calculated using values obtained from the Environmental Protection Agency's National Emissions Inventory, 2017, while deaths and DALYs estimates were calculated using data from the Institute of Health Metrics and Evaluation's global burden of risk factors study, the US decennial census, and the US Centers for Disease Control. We also propose and implement a conceptual framework for identifying the optimal subsidy upon accounting for health benefits arising from reducing conventional tillage, and we discuss strategies to achieve conservation tillage. Annual PM2.5 emissions from crop tillage is about 0.25 million tons. We estimate that approximately 1000 annual deaths and 22,000 DALYs from CVD, as well as 300 annual deaths and 7400 DALYs from COPD, were attributable to tillage-related PM2.5 emissions. Tillage related primary PM2.5 emissions contribute about 0.002 % of total CVD and COPD deaths in the United States, and its related health economic value loss is about 12.9 billion USD annually. About 350 annual deaths may be averted upon a shift from conventional to conservation tillage. Conservation tillage is generally adopted when the pecuniary and soil health benefits exceed those from adopting intensive tillage. Agricultural policies and on-farm measures that may help reduce intensive tillage, and the related PM2.5 emissions, include subsidies for adopting conservation tillage and carbon capture credits, use of herbicides and herbicide-tolerant crops, protecting herbicide-tolerance traits, planting cover crops, and use of windbreaks.

Cementing acetabular liners into secure cementless shells for polyethylene wear provides durable mid-term fixation.

BACKGROUND: In a previous experiment studying cementation of liners into cementless acetabular shells, placing grooves in the liner in a spider-web configuration created the greatest construct strength. Scoring shells without screw holes or other texturing helped prevent failure at the shell-cement interface. However, it was unclear whether these practices caused durable constructs in patients. QUESTIONS/PURPOSES: We therefore determined (1) rerevision rates; (2) functional scores (Harris hip scores, WOMAC, and SF-36); (3) acetabular loosening rates; and (4) acetabular osteolysis rates in patients in whom we cemented nonconstrained liners into well-fixed and well-positioned acetabular shells. METHODS: We prospectively followed 30 patients with 31 total hip arthroplasties in which a worn acetabular liner was revised by cementing a new liner into the existing shell that was stable and well positioned. Acetabular liners were prepared as determined by our previous study. Twenty-seven of the 30 patients (28 hips) were evaluated clinically. We recorded revisions and determined radiographic loosening and osteolysis. The minimum clinical followup was 2 years (mean, 5.3 years; range, 2-10 years). Twenty-six hips (87%) had minimum 2-year radiographic followup with an average length of 4.8 years. RESULTS: No hip required rerevision during the followup interval. Two hips (6%) dislocated once, both treated nonoperatively. Harris hip scores, WOMAC, and SF-36 scores increased over preoperatively at last followup. All acetabular shells and liners were radiographically stable without evidence of loosening or progressive acetabular osteolysis. CONCLUSIONS: Cementation of a liner into a well-fixed cementless shell after scoring in a spider-web configuration provided secure fixation with no failures of the construct at average 5.3 years followup. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Emerging weed resistance increases tillage intensity and greenhouse gas emissions in the US corn-soybean cropping system.

Tillage is a common agricultural practice that helps prepare the soil and remove weeds. However, it remains unknown how tillage intensity has evolved and its effect on net greenhouse gas (GHG) emissions. Here, using a process-based modelling approach with a multi-source database, we examined the change in tillage intensity across the US corn-soybean cropping systems during 1998-2016 and the impact of tillage intensity on soil GHG emissions. We found that tillage intensity first decreased and then, after 2008, increased, a trend that is strongly correlated with the adoption of herbicide-tolerant crops and emerging weed resistance. The GHG mitigation benefit (-5.5 ± 4.8 TgCO2e yr-1) of decreasing tillage intensity before 2008 has been more than offset by increased GHG emissions (13.8 ± 5.6 TgCO2e yr-1) due to tillage reintensification under growing pressure of weed resistance. As weed resistance persists or grows, tillage intensity is anticipated to continue rising, probably increasing GHG emissions. Our results imply that farmers' choices in managing herbicide resistance may help mitigate agricultural GHG emissions, underscoring the importance of an alternative strategy to control weeds.

Analysis of the OITE Oncology Section: An Updated Review of Years 2013 to 2019.

OBJECTIVES: The importance of the Orthopaedic In-Training Examination (OITE) is well documented. The purpose of this study is to provide an updated analysis of the oncology section compared to the review by Frassica et al. from 2002 to 2006, as a means to provide insight into more focused resident study. DESIGN: This study is a retrospective database review using published OITE exams from years 2013 to 2019. Methods were based off a previous review by Frassica et al. where oncology-related questions were analyzed for underlying diagnosis, benign versus malignant condition, imaging and histology provided, and genes/translocations tested. Questions were classified by category and taxonomy. RESULTS: Oncology-related questions per exam ranged from 19 (7%) to 23 (8.4%) of total questions, which is fewer than years 2002 to 2006. Twenty malignant and 27 benign entities were tested with malignant conditions tested at a higher rate of 1.3:1 versus benign. Eighteen combinations of imaging modalities were provided for analysis versus 11 from 2002 to 2006. With regard to taxonomy, the average number of questions per classification ranged from 2.4 to 5.4. The least common classification tested was treatment modality and the most commonly tested classification was treatment from diagnosis (taxonomy 3). Previously, tumor knowledge (taxonomy 1) was most tested with an average of 8.8 questions per exam. 12 questions were directly related to genes and translocations across all years. CONCLUSIONS: Oncology questions made up a smaller percentage of the OITE exam than previous years, although more conditions were tested using more imaging combinations, necessitating a wider range of knowledge. However, malignant conditions continue to be tested more commonly. There has been a shift toward Taxonomy 3 level questions, indicating a higher level of thought processing required from residents as opposed to recall. Additionally, genes and translocations became more commonly tested throughout the most recent analysis, indicating a focus for future years of study.

Durability of second-generation extensively porous-coated stems in patients age 50 and younger.

UNLABELLED: Early versions of uncemented femoral total hip stems were often associated with thigh pain thought to be due to micromotion between the implant and bone in the distal uncoated regions. An extensively coated stem was introduced in 1992 to reduce that risk. We therefore asked whether second-generation extensively porous-coated cementless femoral stems in patients younger than 50 years of age would (1) be durable in terms of revisions; (2) provide high functional scores and reduce thigh pain; and (3) show radiographic signs of durability, including a reduction in stress shielding. We prospectively followed all 100 patients (115 hips) age 50 and younger treated with primary cementless total hip arthroplasties using a second-generation extensively porous-coated femoral stem between June 1994 and December 1999. The average age was 39.6 years (range, 17-50 years). The stems were mated to cementless acetabular components. Ninety patients were followed for a minimum of 5 years (mean, 8.6 years; range, 5-10 years). One stem was revised after a periprosthetic fracture. None were revised for loosening and all stems demonstrated bony ingrowth at last followup. No acetabular shell was revised for loosening and none was radiographically loose. Six acetabular liners were revised for wear (three each were 22-mm and 26-mm heads). This second-generation extensively porous-coated stem was durable at 5- to 10-year followup in this young active population. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Author Correction: The Impact of Bt Corn on Aflatoxin-Related Insurance Claims in the United States.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The Impact of Bt Corn on Aflatoxin-Related Insurance Claims in the United States.

Previous field studies have reached no collective consensus on whether Bt corn, the most commonly planted transgenic crop worldwide, has significantly lower aflatoxin levels than non-Bt isolines. Aflatoxin, a mycotoxin contaminating corn and other commodities, causes liver cancer in humans and can pose severe economic losses to farmers. We found that from 2001-2016, a significant inverse correlation existed between Bt corn planting and aflatoxin-related insurance claims in the United States, when controlling for temperature and drought. Estimated benefits of aflatoxin reduction resulting from Bt corn planting are about $120 million to $167 million per year over 16 states on average. These results suggest that Bt corn use is an important strategy in reducing aflatoxin risk, with corresponding economic benefits. If the same principles hold true in other world regions, then Bt corn hybrids adapted to diverse agronomic regions may have a role in reducing aflatoxin in areas prone to high aflatoxin contamination, and where corn is a dietary staple.

Gender Influences Gait Asymmetry following Bicruciate-Retaining Total Knee Arthroplasty.

This is an experimental study. Gender has been reported to influence outcomes in patients with total knee arthroplasty (TKA) for knee osteoarthritis (OA). However, the influence of gender on three-dimensional (3D) in vivo kinematics during gait remains unclear. This study aimed to determine if 3D gait kinematics, including 3D knee translations and rotations, differed in men and women following bicruciate-retaining (BCR) TKA. Twenty-nine well-functioning unilateral BCR TKA patients (14 males and 15 females) underwent evaluation of both knees during level walking on a treadmill at a self-selected speed using a dual fluoroscopic imaging system. Interlimb comparisons of in vivo 6 degree-of-freedom kinematics were compared between male and female patients. Differences of pre- and postoperative Knee Society scores (KSSs) were compared between the groups. Both groups were matched regarding age and body mass index. Both male and female patients demonstrated improvement in their postoperative KSSs. Statistically significant differences were observed with respect to spatiotemporal anterior-posterior interlimb translations (p < 0.05). Although females presented more femoral posterior translation in the operative knee than the nonoperative knee during most of the stance phases (2.8 vs. -1.6 mm), males exhibited less femoral translation in the operative knee than the nonoperative knee (2.3 vs. -1.8 mm), when interlimb differences were detected during stance phase. Results demonstrated that there are 3D motion asymmetries of the knee in both male and female unilateral BCR TKA patients during gait with anterior-posterior interlimb asymmetries significantly greater in female than male participants. This suggests that gender may influence the in vivo knee kinematics in BCR TKA patients during gait.