Search

Category: Ankle; Ankle Arthritis Introduction/Purpose: Significant preoperative varus tibiotalar deformity was once believed to be a contraindication to performing total ankle arthroplasty (TAA). While correction of ankle deformity has been shown to be possible, the ability to restore neutral alignment in more severe ankle arthritis is still a concern. Preoperative CT derived navigation is gaining popularity for its ability to accurately restore neutral alignment in TAA, in addition to decreasing operative and fluoroscopic times. The primary goal of this study was to evaluate whether accuracy and reproducibility of final implant positioning using patient specific guides were influenced as varus deformity became more severe in patients undergoing TAA. Methods: A retrospective review of 32 patients with varus end-stage ankle arthritis who underwent TAA utilizing total ankle implants with CT derived patient-specific guides was conducted. Preoperative computed tomography (CT) scans were obtained to assess coronal plane deformity, mechanical and anatomic alignment, and build patient-specific guides that referenced bony anatomy. Preoperative weightbearing radiographs were used to measure the tibiotalar and talar tilt angles to assess coronal plane deformity severity and congruency, respectively. Patients were subcategorized into varying degrees of deformity based on their tibiotalar angles (15° severe). The first postoperative weightbearing radiograph following surgery was used to measure coronal plane alignment of the tibial implant relative to the target axis determined by the preoperative CT template. Results: The average preoperative varus deformity, as determined by the tibiotalar angle, was 6.06° (range: 0.66- 16.3°) for the entire cohort. Average preoperative varus deformity was 2.63° for the 'neutral' group, 7.64° for the mild group, 11.5° for the moderate group and 16.3° for the severe group. Postoperative weightbearing alignments for 96.9% (30/31) of patients demonstrated neutral implant alignment (< 5°). Relative to the CT derived target axis, the average tibial implant coronal deviation for all patients was 1.54° (range: 0.17-5.7°). The average postoperative coronal alignment relative to the target axis was 1.61° for the neutral group, 1.78° for the mild group, 0.94° for the moderate group, and 1.41° for the severe group. There was no statistically significant difference in final implant alignment relative to the target axis between deformity subgroups (p= 0.256). Conclusion: The results of our study further support that neutral postoperative TAA alignment can repeatably be obtained using preoperative CT derived patient specific instrumentation (PSI). Furthermore, the accuracy and reproducibility of achieving neutral postoperative radiographic alignment with PSI does not appear to be impacted by worsening varus ankle deformity. All but one patient (96.9%) achieved neutral postoperative alignment relative to the predicted target axis, with the only outlier being from the mild deformity subgroup. Future studies are warranted assessing the effect that even greater coronal plane deformity (>20 °) has on the accuracy of TAA implantation using PSI.

© 2020 The Author(s) Formalised knowledge systems, including universities and research institutes, are important for contemporary societies. They are, however, also arguably failing humanity when their impact is measured against the level of progress being made in stimulating the societal changes needed to address challenges like climate change. In this research we used a novel futures-oriented and participatory approach that asked what future envisioned knowledge systems might need to look like and how we might get there. Findings suggest that envisioned future systems will need to be much more collaborative, open, diverse, egalitarian, and able to work with values and systemic issues. They will also need to go beyond producing knowledge about our world to generating wisdom about how to act within it. To get to envisioned systems we will need to rapidly scale methodological innovations, connect innovators, and creatively accelerate learning about working with intractable challenges. We will also need to create new funding schemes, a global knowledge commons, and challenge deeply held assumptions. To genuinely be a creative force in supporting longevity of human and non-human life on our planet, the shift in knowledge systems will probably need to be at the scale of the enlightenment and speed of the scientific and technological revolution accompanying the second World War. This will require bold and strategic action from governments, scientists, civic society and sustained transformational intent.

Category: Ankle; Trauma Introduction/Purpose: For unstable ankle fractures, surgeons typically employ the long-time standard of care; that is, open reduction and internal fixation with plate and screws. For patients with increased risk of soft tissue complications, a relatively newer construct includes intramedullary distal fibula fixation offering a viable option providing similar union rates, fracture alignment, and theoretical lower infection rate. Our study examines an intramedullary system with a novel design featuring fixation by proximal talons ensuring maintenance of alignment, rotation, and prevention of fracture settling. Our research builds on recent published work evaluating this intramedullary device. However, our study is the largest case-series, to our knowledge to assess time to weightbearing, fracture union and union rate as well as the first to assess safety and reproducibility of percutaneous reduction. Methods: A retrospective case-series was conducted on all skeletally mature patients with unstable ankle fractures treated with the same intramedullary distal fibular fixation. Surgeries were performed by a single surgeon between September 2015 and August 2019. Patient post-operative imaging was carefully assessed for quality of reduction, classifying reductions as ‘good,’ ‘acceptable,’ or ‘poor,’ also assessing for union and fracture settling. Patient charts were also assessed for comorbidities, injury pattern, fracture classification, associated injuries, fracture reduction method, perioperative complications, tourniquet time, characteristics of fracture union, time to weight bearing, and need for additional surgery. Results: Fifty-one patients were included in the study. Mean follow-up time was 32.2 weeks. Four fractures were bimalleolar (7.8%), 44 were isolated distal fibula fractures (86.3%), and 3 were trimalleolar fractures (5.9%). Two percent were Weber A, 77% Weber B, and 11% Weber C. Thirty-five (69%) reductions were achieved closed or percutaneously without complications. Based on reduction classification system, 47 fracture reductions (92%) were classified as ‘good’ and 4 (8%) were ‘acceptable’. All but one fracture (98%) went on to union. Average time to union was 10.3 weeks. Average weightbearing in a walking boot was at 6.8 weeks and 11.2 weeks without immobilization. One patient (2%) had a superficial wound infection, and there were no deep infections. Diabetes, smoking, and neuropathy were not predictive of complications. Conclusion: Our study strengthens the growing body of evidence supporting the safety and efficacy for a novel intramedullary device with unique proximal fixation. To our knowledge, this is currently the largest retrospective case-series in the literature evaluating this device. Fracture union and union rates were found to be acceptable for unstable ankle fracture patterns and infections rates were found to be very low, consistent with previous research. Percutaneous reduction of the lateral malleolus did not result in any injury to nearby anatomic structures or unsatisfactory fracture alignment. Lastly, consistent time to weight bearing following surgery could safely be achieved without consequence.

The main objectives of this analysis are to examine the benefits and costs of fuel-saving technologies for new heavy-duty vehicles (HDVs) in India over the next 10 years and, to explore how various scenarios for the deployment of vehicles with these technologies will impact petroleum consumption and carbon dioxide (CO2) emissions over the next three decades. The study team developed simulation models for three representative HDV types—a 40-tonne tractor-trailer, 25-tonne rigid truck, and 16-tonne transit bus—based on top-selling vehicle models in the Indian market. The baseline technology profiles for all three vehicles were developed using India-specific engine data and vehicle specification information from manufacturer literature and input from industry experts. For each of the three vehicles we developed a comprehensive set of seven efficiency technology packages drawing from five major areas: engine, transmission and driveline, tires, aerodynamics, and weight reduction. Our analysis finds that India has substantial opportunity to improve HDV fuel efficiency levels using cost-effective technologies. Results from our simulation modeling of three representative HDV types—a tractor-trailer, rigid truck, and transit bus—reveal that per-vehicle fuel consumption reductions between roughly 20% and 35% are possible with technologies that provide a return on the initial capital investment within 1 to 2 years. Though most of these technologies are currently unavailable in India, experiences in other more advanced markets such as the US and EU suggest that with sufficient incentives and robust regulatory design, significant progress can be made in developing and deploying efficiency technologies that can provide real-world fuel savings for new commercial vehicles in India over the next 10 years. Bringing HDVs in India up to world-class technology levels will yield substantial petroleum and GHG reductions. By 2030, the fuel and CO2 reductions of the scenarios range from 10% to 34%, and at the end of 2050, these reductions grow to 13% and 41%. If we constrain the analysis to select the most efficient technology package that provides the fleets with payback times of 3 years or less, there are annual fleet-wide savings of roughly 11 MTOE of diesel and 34 MMT of CO2 in 2030, and this grows to 31 MTOE and 97 MMT by 2050.

The authors analyzed projective data obtained from 141 college students who wrote stories on three separate occasions to selected cards from the Thematic Apperception Test (TAT). The students included 46 members of support groups for bereaved college students, 34 members of a bereavement control group, and 61 nonbereaved students. The study used a repeated-measures pretest-posttest control group design to gather longitudinal data about the trajectory of bereavement with and without support group intervention. Coders, who reached consistently high interrater reliability, looked for themes of death, grief, coping, and affiliation in the stories. Multivariate analysis of variance (MANOVA) and repeated-measures MANOVA tests were applied to analyze coding results. Overall MANOVA results indicated significant group differences in the responses to the TAT cards. Repeated-measures MANOVA found group differences in use of themes of death and grief and found Group x Time differences in maintaining a sense of self-efficacy while in a crisis. A majority of the stories contained affiliation imagery but without any group differences in the use of such imagery.

n/a