bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid Mesoscale Environmental Changes Accompanying Genesis of an Unusual Tornado
Authors: Koch Steven E. , Ware Randolph , Jiang Hongli , Xie Yuanfu 
Published: March 2016

AbstractThis study documents a very rapid increase in convective instability, vertical wind shear, and mesoscale forcing for ascent leading to the formation of a highly unusual tornado as detected by a ground-based microwave radiometer and wind profiler, and in 1-km resolution mesoanalyses. Mesoscale forcing for the rapid development of severe convection began with the arrival of a strong upper-level jet streak with pronounced divergence in its left exit region and associated intensification of the low-level flow to the south of a pronounced warm front. The resultant increase in stretching deformation along the front occurred in association with warming immediately to its south as low-level clouds dissipated. This created a narrow ribbon of intense frontogenesis and a rapid increase in convective available potential energy (CAPE) within 75 min of tornadogenesis. The Windsor, Colorado, storm formed at the juncture of this warm frontogenesis zone and a developing dryline. Storm-relative helicity suddenly increased to large values during this pretornadic period as a midtropospheric layer of strong southeasterly winds descended to low levels. The following events also occurred simultaneously within this short period of time: a pronounced decrease in midtropospheric equivalent potential temperature θe accompanying the descending jet, an increase in low-level θe associated with the surface sensible heating, and elimination of the capping inversion and convective inhibition. The simultaneous nature of these rapid changes over such a short period of time, not fully captured in Storm Prediction Center mesoanalyses, was likely critical in generating this unusual tornadic event.
A low cost virtual reality system for home based rehabilitation of the arm following stroke: a randomised controlled feasibility trial
Authors: Standen PJ , Threapleton K , Richardson A , Connell L , Brown DJ , Battersby S , Platts F , Burton A 
Published: March 2016

Objective: To assess the feasibility of conducting a randomised controlled trial of a home-based virtual reality system for rehabilitation of the arm following stroke. Design: Two group feasibility randomised controlled trial of intervention versus usual care. Setting: Patients’ homes. Participants: Patients aged 18 or over, with residual arm dysfunction following stroke and no longer receiving any other intensive rehabilitation. Interventions: Eight weeks’ use of a low cost home-based virtual reality system employing infra-red capture to translate the position of the hand into game play or usual care. Main measures: The primary objective was to collect information on the feasibility of a trial, including recruitment, collection of outcome measures and staff support required. Patients were assessed at three time points using the Wolf Motor Function Test, Nine-Hole Peg Test, Motor Activity Log and Nottingham Extended Activities of Daily Living. Results: Over 15 months only 47 people were referred to the team. Twenty seven were randomised and 18 (67%) of those completed final outcome measures. Sample size calculation based on data from the Wolf Motor Function Test indicated a requirement for 38 per group. There was a significantly greater change from baseline in the intervention group on midpoint Wolf Grip strength and two subscales of the final Motor Activity Log. Training in the use of the equipment took a median of 230 minutes per patient. Conclusions: To achieve the required sample size, a definitive home-based trial would require additional strategies to boost recruitment rates and adequate resources for patient support.
Biomechanical Comparison of Intramedullary Screw Versus Low-Profile Plate Fixation of a Jones Fracture
Authors: Huh Jeannie , Glisson Richard R. , Matsumoto Takumi , Easley Mark E. 
Published: March 2016

Background: Intramedullary screw fixation of fifth metatarsal Jones fractures often produces satisfactory results, however, nonunion and refracture rates are not negligible. The low-profile “hook” plate is an alternative fixation method that has been promoted to offer improved rotational control at the fracture site, but this remains to be proven. The purpose of this study was to document biomechanical performance differences between this type of plate and a contemporary solid, dual-pitch intramedullary screw in a cadaveric Jones fracture model. Methods: Simulated Jones fractures were created in 8 matched pairs of fresh-frozen cadaveric fifth metatarsals. One bone from each pair was stabilized using an intramedullary TriMed Jones Screw and the other using a TriMed Jones Fracture Plate (TriMed, Inc, Santa Clarita, CA). Controlled bending and torsional loads were applied. Bending stiffness and fracture site angulation, as well as torsional stiffness, peak torque, and fracture site rotation were quantified and compared. Results: Intramedullary screw fixation demonstrated greater bending stiffness and less fracture site angulation than plate fixation during plantar-to-dorsal and lateral-to-medial bending. Torsional stiffness of screw-fixed metatarsals exceeded that of plate-fixed bones at initial loading; however, as rotation progressed, the plate resisted torque better than the screw. No difference in peak torque was demonstrable between fixation methods, but it was reached earlier in specimens fixed with screws and later in those fixed with plates as rotation progressed. Conclusion: In this cadaveric Jones fracture model, intramedullary screw fixation demonstrated bending stiffness and resistance to early torsional loading that was superior to that offered by plate fixation. Clinical Relevance: Although low-profile “hook” plates offer an alternative for fixation of fifth metatarsal Jones fractures, intramedullary screw fixation may provide better resistance to bending and initiation of fracture site rotation. The influence of these mechanical characteristics on fracture healing is unknown, and further clinical investigation is warranted.
Secondary Arthrodesis After Total Ankle Arthroplasty
Authors: Gross Christopher E. , Lewis John S. , Adams Samuel B. , Easley Mark , DeOrio James K. , Nunley James A. 
Published: March 2016

Background: While it is thought that stresses through the subtalar and talonavicular joints will be decreased after total ankle replacement (TAR) relative to ankle fusion, progressive arthritis or deformity of these joints may require a fusion after a successful TAR. However, after ankle replacement, it is unknown how hindfoot biomechanics and blood supply may be affected. Consequently, subsequent hindfoot joint fusion may be adversely affected. Methods: We retrospectively identified a consecutive series of 1001 primary TARs performed between January 1998 and December 2014. We identified patients who underwent a secondary triple, subtalar or talonavicular arthrodesis to treat progressive arthritis or pes planus deformity. Clinical outcomes including pain and functional outcome scores, revision procedures, delayed union, nonunion, complications, and failure rates were recorded. Twenty-six patients (2.6%) required a subtalar (18), talonavicular (3), talonavicular and subtalar (3), or triple arthrodesis (2). Of these patients, 14 (54%) were males with an average age of 63.2 years and a mean 70.9 months follow-up. We then compared these patients to 13 patients who had a subtalar fusion after an ankle arthrodesis. Results: The most common type of fixation used was 2 variable-pitch screws across each joint. Fresh-frozen allograft cancellous chips were the most common supplement to the fusion construct (80.8%). The mean time between TAR and secondary fusion procedure was 37.5 months. Overall, 92.3% of the patients went on to fusion. Two patients (7.7%) had a delayed union and 2 patients had a nonunion (7.7%) and were considered operative failures. There were 3 repeat procedures related to the arthrodesis procedure: 1 conversion of a subtalar to a triple arthrodesis, 1 revision talonavicular fusion, and 1 revision subtalar fusion. The average time to weight bearing after arthrodesis was 8.7 weeks; the mean time to radiographic and clinical fusion was 26.5 weeks. There were no secondary complications associated with the arthrodesis. Pain and functional outcome scores improved significantly. There were no differences in the rates of subsequent fusions among implant choices, though the time to fusion in the mobile-bearing prosthesis was significantly longer than the 2 fixed-bearing prostheses. Compared with the data of 13 patients with prior ipsilateral ankle arthrodeses and subtalar fusions, patients who had an ankle replacement had a higher fusion rate ( P = .03) and had a similar time to fusion. Conclusion: Hindfoot arthrodesis following a TAR was safe and effective in improving function and pain. Additionally, a hindfoot arthrodesis following a TAR had a higher fusion rate than a subtalar fusion following an ankle arthrodesis. Although the time to healing was relatively long, various hindfoot fusions were used to treat progressive arthritis and deformity with high fusion rates. Level of Evidence: Level III, comparative case series.
Global Crisis, Regulatory Reform and International Policy Coordination
Authors: Nachane D. M. 
Published: March 2016

The recent global crisis has brought the following issues to the forefront of macro-policy analysis: (a) procyclicality of bank capital regulation, (b) role of asset bubbles, (c) high social costs of financial failures and (d) high leverage of financial institutions (FIs). It has been realized by the global community that tackling these problems calls for a coordinated approach in which the following agencies will have to play a vital role: National regulatory and supervisory (R&S) authorities International Monetary Fund (IMF) Financial Stability Forum (FSF) International standard setting bodies—Basel Committee on Banking Supervision (BCBS), International Organization of Securities Commissions (IOSCO), etc. Influential groups like G-20 For purposes of this article, we focus on the role of national R&S authorities and find that this role revolves around seven key policy areas, namely (a) making monetary policy respond to asset prices, (b) strengthening and expanding the scope of regulation and supervision, (c) controlling leverage of FIs, (d) dampening procyclicality of capital requirements, (e) reducing costs of financial failures, (f) devising market incentives for prudent behaviour and (g) a shift from micro-prudential to macro-prudential regulation. We examine to what extent the official financial supervisory and regulatory authorities in India have fulfilled this role successfully. JEL Classification: E6, F4, F5
Patella height following biplanar medial open-wedge high tibial osteotomy and its relevance for Clinical Outcome
Authors: Bode Gerrit , Niemeyer Philipp , Südkamp Norbert P. , Feucht Matthias , Mehl Julian 
Published: March 2016

Aims and Objectives: The medial medial open-wedge tibial osteotomy (OW HTO) has become increasingly important in the treatment of cartilage damage in the medial compartment with accompanying varus deformity in recent years. The technique of the biplanar, proximally initiated OW-HTO leads to a reduction of the patellar height. Relationships with functional outcome, and thus the clinical relevance of this observation, has not been investigated adequately so far. The aim of this study was to evaluate the influence of altered patellofemoral geometry on the functional outcome after OW HTO. Materials and Methods: In 205 patients (age 44.46 ± 10.43 years MW) with cartilage damage in the medial compartment and existing varus deformity biplanar, proximally directed OW HTO (TomoFix, Synthes, Solothurn, Switzerland) was perfermed between January 2005 and December 2013. Insall-Salvati index and Caton-Deschamps index were determined rom pre- and postoperative lateral radiographs of these patients. The evaluation of the patients was performed using standardized measuring instruments (preoperatively: visual analogue scale (VAS) and Lysholm score after surgery: VAS, Lysholm, KOOS and KOOS4). In the event of a radiological patella baja (Insall-Salvati index> 1.2; Caton-Dechamp less then 0,6 correlation of patellar height and the functional scores was performed using SPSS 21.0 (IBM Corp., Armonk, United States). A p-value of 0.05 was considered statistically significant. Results: At an average follow-up of 68.65 (SD ± 30.26) months, a defect size of 4.32 MW (SD ± 3.01) cm2, a varus deformity of MW 6.04 (SD ± 2.83) ° and postoperative leg axis of MW 2.26 ± 1.74 ° valgus data analysis resulted in significant postoperative changes in the patellar indices (Insall-Salvati index preoperatively 0.94 ± 0.17 vs. 0.91 ± 0.20 postoperatively; Caton- Dechamp index preoperatively 1.03 ± 0.1,69 vs. 0.89 ± 0.17 postoperatively, p = 0.00). The carried out correlation analysis revealed significant correlations for KOOS symptoms and KOOS4 (p = 0.034 and 0.01). Conclusion: The proximally directed biplanar medial open-wedge osteotomy leads to significant changes in the patellofemoral joint section in the sense of patella baja. These kinematic changes correlate with poorer postoperative functional results, so that in patients with preexisting pathological patellar height a modification of the classical osteotomy technique such as a to leave the tibial tuberosity attached tot he proximal tibia should be discussed.
The impact of fixation methods on the risk of revision in ACL reconstruction - a study from the Scandinavian ACL registries, 2004-2011
Authors: Persson Andreas , Gifstad Tone , Forssblad Magnus , Lind Martin , Engebretsen Lars 
Published: March 2016

Aims and Objectives: The hamstring autograft is one of the most common grafts used for anterior cruciate ligament reconstruction (ACLR) and a large number of fixation methods are available. There are no studies investigating the risk of revision for specific fixation devices. Revision ACLR is a relatively rare event and large registry-based prospective studies make it possible to analyze differences in risk of revision according to clinical and demographic factors. The aim of the present registry-based study was to describe the current use of fixation method and to compare risk of revision between various femoral and tibial fixation methods in Scandinavia during the study period. Materials and Methods: A total of 38 666 patients undergoing primary ACL reconstructions in the period 2004-2011 were included in the present study. Less frequently used fixation devices were grouped according to the point of graft fixation. To compare the risk of revision between various fixation methods, the multiple Cox proportional hazard (PH) regression model was applied. Hazard rate ratios (HR with 95% confidence interval (CI)) were reported as measure of effect. Results: The median follow-up time was 3 years (range 0 to 8 years). The present data included a total of 1042 revision ACL reconstructions. Based on a Cox PH regression model stratified for country and mutual adjustment for gender, age at surgery (five-year categories), activity at the time when the primary injury occurred, femoral fixation and tibial fixation, we found a significantly lower risk of revision for the transfemoral fixation devices Rigidfix (0.7 (0.6-0.8)) and Transfix (0.7 (0.6-0.9)) compared with the cortical device Endobutton (ref.). The same model showed that a retro interference screw used for tibial fixation had a higher risk of revision (1.9 (1.3-2.9)) compared with a standard interference screw (ref.). Conclusion: In view of the findings in the present study, both femoral and tibial fixation method of hamstring autografts seem to be of significance when evaluating the risk of revision.
Does prosthesis design affect the need for secondary resurfacing in total knee arthroplasty?
Authors: Rotigliano Niccolò , Hirschmann Michael T. 
Published: March 2016

Aims and Objectives: The purpose of this retrospective consecutive study was to compare the rate of secondary resurfacing in consecutive series of five different TKA systems. It was our hypothesis that different brands of TKA show different rates of secondary resurfacing. Materials and Methods: A retrospective study was performed on data from patients who underwent TKA without primary patellar resurfacing from 2004 to 2012 in an university affiliated hospital. The study cohort included 784 patients (m:f=302:482, mean age at surgery±SD 71±10) operated with TKA during this period. Five different cruciate-retaining TKA systems were used in consecutives series. These were the following: A) Triathlon, Stryker, Switzerland (n=296), B) PFC Sigma, DepuySynthes, Switzerland (n=215), C) LCS, DepuySynthes, Switzerland (n=80), D) Balansys, Mathys, Bettlach, Switzerland (n=129), E) Duracon, Stryker, Switzerland (n=64). Data was retrospectively obtained from our different hospital archives. Patients demographics, age at surgery, type of total knee arthroplasty were noted. In addition, the data were screened for a secondary resurfacing in each patient. On anterior-posterior, lateral and skyline view radiographs different measurements were performed. TKA component position was assessed on radiographs with respect to "The knee society total knee arthroplasty roentgenographic evaluation and scoring system (TKA-RESS). Pearson Chi square test was used to compare differences between groups (p<0.05). There was no significant difference between the groups in terms of age, gender, and radiological outcomes. Results: Twenty-six of 784 patients (3.3%) underwent secondary resurfacing due to patellofemoral pain during follow-up. In group A four of 296 patients (1.4%), in group B fifteen of 215 patients (7%), in group C four of 80 patients (5%), in group D two of 129 patients (1.6%), in group E one of 64 patients (1.6%) underwent secondary patellar resurfacing during follow-up. There was a statistically significant difference between group B and A, D and E as well as between group C and A, D and E (p<0.001). Conclusion: Prosthesis design influences the need for secondary resurfacing of the patella. It was shown that the rate ranges from 1 to 7%. The highest rate for secondary resurfacing was found in the PFC Sigma TKA.
A Comparison of Anatomic Double- And Single-bundle Techniques for Anterior Cruciate Ligament Reconstruction, A Prospective Randomized Study with A 5-year Follow-up
Authors: Karikis Ioannis , Desai Neel , Sernert Ninni , Rostgard-Christensen Lars , Kartus Juri T. 
Published: March 2016

Objectives: The purpose of this study was to compare the mid-term outcome after arthroscopic anterior cruciate ligament (ACL) reconstruction with either the anatomic double-bundle (DB) or anatomic single-bundle (SB) technique using hamstring tendon autografts in an unselected group of patients. Methods: 103 patients (33 women, 70 men; median age, 27 years; range, 18-52 years) were randomized and underwent ACL reconstruction (DB group; n=53 and SB group; n=50). All reconstructions were performed anatomically, identifying the ACL footprints, using the anteromedial portal for the femoral tunnel drilling and utilizing interference screw for tibial and femoral fixation. One blinded observer examined the patients both preoperatively and at follow-up (median, 64 months; range, 55-75 months). Radiographic evaluation of OA was performed using the Ahlbäck, Kellgren-Lawrence and Fairbanks grading systems in the early postoperative period and at follow up. Results: Preoperatively, no differences were found between the study groups apart from the pre-injury Tegner activity level, which was lower in the DB group (p=0.02). Eighty-seven patients (83%) were available for examination at 5-year follow-up. There were no significant differences between the groups in terms of the pivot-shift test, KT-1000 arthrometer laxity measurements, manual Lachman test, One-leg-hop test, Square-hop test, range of motion, Lysholm knee scoring scale, Tegner activity scale and Knee Injury and Osteoarthritis Outcome Score (KOOS). Correspondingly, no differences were found between the groups regarding the presence of OA at follow-up. Both DB and SB groups improved significantly at follow-up compared with the preoperative assessment. Conclusion: At mid-term follow-up of an unselected group of patients, anatomic DB reconstruction was not superior to anatomic SB reconstruction in terms of the pivot-shift test or subjective and objective outcome variables, as seen in this prospective randomized study. Furthermore, there was no difference in terms of the presence of OA at follow-up.
Unintended Consequences of Concussion Prevention in NCAA Football
Authors: Westermann Robert W. , Wehr Peter , Amendola Annunziato 
Published: March 2016

Objectives: Both lower extremity and head injuries are common in American Football players. Concussions, or Mild Traumatic Brain Injuries (MTBIs), have gained increased interest in the past decade. Recurrent MTBIs have been associated with late-life cognitive impairment and depression in American Football populations.2, 3 Beginning in 2008, the NCAA introduced rule changes with the intent to halt or reverse the increasing rates of MTBIs in its players. Lower-extremity injuries in American football populations have been associated with increased rates of post-traumatic osteoarthritis1 and significantly contribute to disability in retirement. While lower extremity injury rates have been studied and associated with weather5 and playing surface4, no such study has sought an association between lower extremity injury with the timing/introduction of rule changes used to prevent head injuries. The purpose of this study was to assess if lower extremity injury rates are increasing after concussion rule changes. We hypothesize that there may be a compensatory increase in lower extremity injury rates as players act to avoid head-to-head contact and comply with instated rules. Methods: The NCAA Injury Surveillance System (NCAA ISS) database was queried for in-game injuries suffered between 2009-2014. All injuries suffered by NCAA Football players that occurred in competition were identified. Injuries that did not result in lost participation time were excluded. Lower extremity injuries that resulted in lost time included injuries to the thigh/upper leg, knee, lower leg/Achilles, ankle and foot. All concussions resulting in lost time were also identified during the same time period for comparison. Data regarding athletic exposures was collected in order to calculate the incidence of injury. Results: Between 2009 and 2014, 48 NCAA Football programs provided data on123 team-seasons to the NCAA ISS for analysis. The incidence of lower extremity injuries increased from 9.45 injuries per 1000AE in the 2009-2010 season to 12.63 injuries per 1000AE in the 2013-2014 season. The rate of concussions suffered by American Football players, during the same time period, did not significantly change (1.64 concussions per 1000AE’s in 2009-2010 season versus 2.87 concussions per 1000 AE’s in the 2013-2014 season) [Graph 1]. Conclusion: Given heightened societal interest in concussions, the NCAA has implemented several rule changes in order to influence how American Football is played. Since the initiation of these rule changes, concussion rates have remained stable. During our study period, injuries to the lower extremity have increased. In order to comply with avoiding head-to-head contact, players may be targeting the lower extremities. This is concerning as lower extremity injuries and post-traumatic osteoarthritis are common causes of disability in retired American Football players.