bluuebunny/crossref_metadata_2025_split huggingface dataset:
Economics 0, 1, 2? – Illustrating the Core Insights of Economic Analysis*
Authors: Hsiung Bingyuan 
Published: July 2017

Economists generally agree that economic analysis constitutes a unique worldview, but there seems to be no consensus about the worldview itself. This paper attempts to outline a possible configuration of the worldview by proposing four fundamental insights of economics. The insights satisfy two criteria: they should be compatible with the mainstream of economics, and they should correspond to the daily experiences of the general public and be useful to them. The four insights can be represented by the numbers of 0, 1, and 2: (1) O > 0; (2) 1+1<2; (3) 1+1>2; (4) 0 ~ 0. First, O > 0 means that man is rational and self-interested. Secondly, 1+1<2 suggests that whatever is, is not necessarily efficient, but there is a reason for it. Third, 1+1>2 argues that for something good to occur, the supporting conditions must be in place. Fourth, 0 ~ 0 implies that the meanings of something are fulfilled by other, relevant things. Abstractly speaking, the first insight is the starting point of economic analysis. The second and third insights represent respectively an unsatisfactory and a satisfactory situation; for either situation, economic analysis can try to advance an explanation. Finally, the fourth insight illustrates on the one hand the core concept of opportunity cost and on the other hand how meanings of things are determined in general. It also implies that given the status quo, a potentially better alternative can and should be looked for consciously. JEL classification: A2, B0.
The Quality of Latin American Institutions
Authors: Krause Martin 
Published: July 2017

Faced with institutional competition, accelerated by the process of globalization, countries have basically two options: participate in it and get their benefits or isolate themselves and be left aside. With a few exceptions, Latin American countries have not been able to cope with competition and are lagging behind. In this article an attempt will be made to evaluate the quality of Latin American institutions in terms of macroeconomic stability and the rule of law through the building of a composite index called “Institutional Quality Index”, averaging together indexes evaluating economic and political issues, trying to capture the essence of institutional arrangements that have allowed countries to progress and showing whether Latin America’s institutions are able to compete in the world arena. It will be concluded that small countries, such as Chile and some islands on the Caribbean and Central America, get better qualifications than larger countries in the region. This may be explained by the fact that their size forces them to be open economies where contracts and property rights are enforced, since their economies would not be self-sustainable if closed. Also, the “heritage” of legal systems such as the British “common law” shows that some countries could get a better performance of justice as shown by, for example, the high qualifications of some Caribbean countries as compared to others in Latin America that inherited the legal systems of Spain or Portugal. A few recommendations follow.
Corruption and Political Interest: Empirical Evidence at the Micro Level
Authors: Dong Bin , Torgler Benno 
Published: July 2017

The topic of corruption has recently attracted a great deal of attention, yet there is still a lack of micro level empirical evidence regarding the determinants of corruption. Furthermore, the present literature has not investigated the effects of political interest on corruption despite the interesting potential of this link. We address these deficiencies by analyzing a cross-section of individuals, using the World Values Survey. We explore the determinants of corruption through two dependent variables (perceived corruption and the justifiability of corruption). The impact of political interest on corruption is explored through three different proxies, presenting empirical evidence at both the cross-country level and the within-country level. The results of the multivariate analysis suggest that political interest has an impact on corruption controlling for a large number of factors. JEL classification: K420, D720, 0170, J240
Surgical Repair of Complete Proximal Hamstring Tendon Rupture
Authors: Klingele Kevin E. , Sallay Peter I. 
Published: July 2017

Background: Complete proximal hamstring tendon rupture is a rare injury associated with significant functional loss. Nonoperative treatment has proven inadequate in returning patients to their previous activity level. Purpose: We wanted to describe the outcome of primary surgical repair of the proximal hamstring tendon avulsion. Study Design: Retrospective cohort study. Methods: Between 1994 and 1999, 11 patients (4 women and 7 men) with an average age of 41.5 years (range, 21 to 51) had a diagnosis of complete proximal hamstring tendon rupture based on mechanism of injury, physical examination, and radiographic assessment. All underwent a single operation followed by standard postoperative physical therapy. At the latest follow-up (average, 34 months), patients completed a questionnaire regarding such outcome parameters as pain, function, leg control, stiffness, return to activity, and overall satisfaction. Results: Isokinetic muscle testing revealed an overall average of 91% return of hamstring muscle strength. Ten of 11 patients were satisfied with the result, and 7 of 9 athletically active patients were able to return to sport an average of 6 months (range, 3 to 10) after surgery. No difference between early and late repairs was identified in regard to functional outcome or return to sport. Conclusions: Satisfactory results can be achieved with both early and late hamstring tendon repairs in a majority of cases with surgical repair.
Clinical Association of Acute Lateral Ankle Sprain with Syndesmotic Involvement
Authors: Uys Hendrik D. , Rijke Arie M. 
Published: July 2017

Background Information concerning the clinical association between syndesmosis injury and grade of lateral ankle ligament damage would aid in the diagnosis and treatment of ankle sprains. Hypothesis Evaluation of lateral ligament injury in terms of percentage tear of both the anterior talofibular and calcaneofibular ligaments can provide information on the extent of syndesmotic involvement. Study Design Prospective cohort study. Methods Twenty-five patients volunteered to have magnetic resonance imaging examinations performed and 21 volunteered to undergo graded stress radiographs. Talar tilt angles were measured from radiographs taken with 0, 6, 9, 12, and 15 daN of force applied medially just above the ankle joint, and the percentage of ligament tear and grade of injury were determined. Scans were obtained with the foot in neutral and plantar flexion to image the anterior talofibular and calcaneofibular ligaments. Results Grades of lateral ligament injury determined by magnetic resonance imaging and graded stress radiography were the same. The extent of syndesmotic injury could be assessed for all patients. Conclusions Intact tibiofibular ligaments were found equally frequently among patients with normal or any grade of lateral ligament damage, but the more severe injuries to the syndesmotic ligaments were associated with normal or minimally traumatized lateral ligaments. The inverse correlation can be explained on the basis of the difference between the mechanisms that precipitate these injuries.
Effects of Meniscal and Articular Surface Status on Knee Stability, Function, and Symptoms after Anterior Cruciate Ligament Reconstruction
Authors: Wu W. Howard , Hackett Thomas , Richmond John C. 
Published: July 2017

Background Concomitant injuries to secondary structures have been proposed as a major cause of failure of anterior cruciate ligament reconstruction. Purpose Our purpose was to determine the relationship between meniscal status at the time of anterior cruciate ligament reconstruction and ultimate long-term function and stability. Study Design Prospective cohort study. Methods We prospectively studied 63 patients for an average of 10.4 years after arthroscopically assisted bone-patellar tendon-bone anterior cruciate reconstruction. All surgeries were performed between 1988 and 1991; concomitant meniscal surgery was performed if necessary. Subjects were divided into subgroups relative to the integrity of their menisci at the end of the reconstruction procedure (intact meniscus, partial meniscectomy, complete meniscectomy). Results Patients who had undergone any degree of meniscal resection reported significantly more subjective complaints and activity limitations than those with intact menisci. Subjective International Knee Documentation Committee and Lysholm scores were lower in the meniscectomy subgroups than in the meniscus-intact group. Objective testing revealed a significantly lower ability to perform the single-legged hop in the meniscectomy subgroups. Ligament stability based on instrumented laxity measurements was not significantly different between the subgroups. Radiographic abnormalities were also more common in the subgroups that had undergone meniscectomy. Conclusions The menisci should be repaired if at all possible, especially in the setting of anterior cruciate ligament reconstruction, for optimal functional outcome and patient satisfaction.
Wrist Pain, Distal Radial Physeal Injury, and Ulnar Variance in Young Gymnasts: Does a Relationship Exist?
Authors: DiFiori John P. , Puffer James C. , Aish Bassil , Dorey Frederick 
Published: July 2017

Background Chronic wrist pain affects up to 79% of young gymnasts. Distal radial growth plate injury and positive ulnar variance have also been reported in this population. Hypothesis There is a relationship between wrist pain, radiographic findings of distal radial growth plate injury, and ulnar variance in skeletally immature young gymnasts. Study Design Cross-sectional study. Methods Fifty-nine gymnasts (28 girls and 31 boys; average age, 9.3 years) completed a questionnaire detailing training and wrist pain symptoms. Each received a wrist examination, grip strength measurement, and bilateral wrist radiographs. Results Wrist pain was reported by 56% of the gymnasts (33 of 59), with 45% (15 of 33) describing pain of at least 6 months’ duration. Factors significantly associated with wrist pain included higher skill level, older age, and more years of training. For those between 10 and 14 years of age, 83% had wrist pain, compared with 44% for those outside of that age range. Fifty-one percent of the gymnasts (30 of 59) had findings of stress injury to the distal radial physis of at least a grade 2; 7% (4) had frank widening of the growth plate. Wrist pain prevalence was significantly related to the grade of radiographic injury. Mean ulnar variance was significantly more positive than established norms. Ulnar variance was not associated with wrist pain or radiographic injury of the distal radial physis. Conclusions Radiographic findings of distal radial physeal injury are associated with wrist pain among young nonelite gymnasts.
Biomechanical Evaluation of a New Ulnar Collateral Ligament Reconstruction Technique with Interference Screw Fixation
Authors: Ahmad Christopher S. , Lee Thay Q. , ElAttrache Neal S. 
Published: July 2017

Background Techniques for ulnar collateral ligament reconstruction have evolved. Hypothesis Ulnar collateral ligament reconstruction with interference screw fixation restores elbow kinematics and failure strength to that of the native ligament. Study Design Controlled laboratory study. Methods Of 10 matched pairs of cadaveric elbows, one underwent kinematic testing under conditions of an intact, released, and reconstructed ligament. Single 5-mm diameter bone tunnels were created at the isometric anatomic insertion sites on the medial epicondyle and sublime tubercle. Graft fixation was achieved with 5 × 15 mm soft tissue interference screws. The reconstructed and contralateral intact elbows were then tested to failure. Results Average stiffness for intact elbows (42.81 ± 11.6 N/mm) was significantly greater than for reconstructed elbows (20.28 ± 12.5 N/mm). Ultimate moment for intact elbows (34.0 ± 6.9 N·m) was not significantly different from reconstructed elbows (30.6 ± 19.2 N·m). Release of the ulnar collateral ligament caused a significant increase in valgus instability. Reconstruction restored valgus stability to near that of the intact elbow. Conclusions With this reconstruction method, failure strength was comparable with that of the native ligament and physiologic elbow kinematics were reliably restored. Clinical Relevance This technique returns elbow kinematics to near normal, with less soft tissue dissection and risk of ulnar nerve injury and ease of graft insertion, tensioning, and fixation.
Recovery of Chondrocyte Metabolic Activity after Thermal Exposure
Authors: Kaplan Lee D. , Chu Constance R. , Bradley James P. , Fu Freddie H. , Studer Rebecca K. 
Published: July 2017

Background The relationship between temperature elevation and thermal exposure time during thermal chondroplasty has implications for cell viability and subsequent articular cartilage function. Purpose To characterize cartilage metabolic changes after exposure to thermal stress and to determine whether changes seen acutely are reversible. Study Design Controlled laboratory study. Methods Human cartilage was exposed to a 45°, 50°, or 55°C bath for up to 3 minutes. Untreated control specimens were analyzed with each group. Viability and metabolic capability of treated and untreated specimens were evaluated immediately or 1 week after thermal stress by using methylthiotetrazole conversion, 3H-serine incorporation into protein, and 35S-sulfate incorporation into newly synthesized proteoglycan. Results Nonarthritic and arthritic articular cartilage metabolic activity declined with increasing thermal exposure. Articular cartilage displayed a recovery from thermal stress after exposure to the 50°C but not the 55°C bath. Arthritic cartilage displayed increased sensitivity with higher temperatures. Conclusions Understanding of the increased sensitivity to thermal stress of arthritic articular cartilage may be helpful in thermally based treatments. Clinical Relevance Further correlation with the temperatures attained during thermal chondroplasty will be necessary to confirm the clinical relevance of these in vitro observations to the use of radiofrequency energy devices to treat partial-thickness chondral lesions.
Twisting and Braiding Reduces the Tensile Strength and Stiffness of Human Hamstring Tendon Grafts Used for Anterior Cruciate Ligament Reconstruction
Authors: Kim David H. , Wilson David R. , Hecker Aaron T. , Jung Tobias M. , Brown Charles H. 
Published: July 2017

Background: Twisting and braiding of four-strand hamstring tendon grafts used for anterior cruciate ligament reconstruction has been proposed, but not proven, as a method of improving tensile properties. Hypothesis: Twisting and braiding four-strand human hamstring tendon grafts will have no significant effect on initial graft strength or stiffness. Study Design: Paired in vitro biomechanical study. Methods: In 12 matched cadaveric pairs, a doubled gracilis and semitendinosus tendon graft from one knee was twisted 180° over a 30-mm length, while the doubled tendon graft from the contralateral knee was prepared for biomechanical testing with the graft strands in a parallel orientation. For an additional 12 matched pairs, a doubled graft was braided into a weave while the contralateral graft was prepared for testing in a parallel orientation. All four strands of each doubled tendon graft were equally tensioned with weights before being clamped in a tendon-freezing grip. Tensile testing was then performed. Results: Twisting decreased graft strength by 26% (P < 0.01) and stiffness by 43% (P < 0.01), while braiding reduced strength by 46% (P < 0.01) and stiffness by 54% (P < 0.01), compared with parallel-oriented grafts. Conclusions: Equally tensioned, parallel four-strand human hamstring tendon grafts were significantly stronger and stiffer than twisted or braided four-strand hamstring tendon grafts. Clinical Relevance: We caution against the use of twisted or braided four-strand hamstring tendon grafts for anterior cruciate ligament reconstruction.
Results of Repeat Meniscal Repair
Authors: Voloshin Ilya , Schmitz Miguel A. , Adams Mark J. , DeHaven Kenneth E. 
Published: July 2017

Background: The efficacy of repeat repair of retorn menisci has not been demonstrated. Purpose: To document clinical and radiographic results of repeat repair of retorn menisci that had previously undergone primary repair. Study Design: Uncontrolled retrospective review. Methods: Eighteen consecutive repeat meniscal repairs were performed over an 11-year period. Results: Fourteen of 18 patients (13 repeat meniscal repairs and 1 second repeat meniscal repair) had clinically intact menisci and were available for a mean follow-up of 7.33 years (range, 3.25 to 13.75). The average durability of the initial repair was 3.46 years (range, 0.17 to 14.67). Five patients sustained a tear at the site of rerepair; one underwent second repeat repair of the meniscus and the other four patients underwent partial meniscectomy. The mean Lysholm score for the remaining 14 patients was 82.1 (range, 38 to 100), and the mean Tegner score was 5.6 (range, 2 to 8). On the International Knee Documentation Committee rating scale, five knees received an overall rating of normal; six, nearly normal; and three, abnormal. Radiographs revealed grade 0 changes (normal) in five of the involved knee compartments and grade I changes (sclerosis or mild narrowing measuring 1 to 2 mm) in the remaining five. Conclusions: Repeat repair of retorn menisci had a 72% survival rate with relief of symptoms and return to high levels of function.
Biomechanical Comparisons of Three Posterior Cruciate Ligament Reconstruction Procedures with Load-Controlled and Displacement-Controlled Cyclic Tests
Authors: Kitamura Nobuto , Yasuda Kazunori , Yamanaka Masanori , Tohyama Harukazu 
Published: July 2017

Background: Biomechanical behaviors of posterior cruciate ligament reconstructions under cyclic loading have not been sufficiently clarified. Hypothesis: Biomechanical behaviors of the reconstruction that involves use of flexor tendons and an Endobutton are significantly different under cyclic loading from behaviors of the two standard reconstructions in which bone-patellar tendon-bone graft is used. Study Design: Controlled laboratory study. Methods: In a porcine model, the tendon/Endobutton reconstruction, the tendon-bone/interference screw reconstruction, and the tendon-bone/tibial-inlay reconstruction were biomechanically compared by using two cyclic tests. In each group of 15 specimens, 5 knees underwent tensile testing without cyclic loading, and the remaining 10 underwent the same tensile test after 5000 cycles of load-controlled or displacement-controlled loading. Results: At the 5000th cycle, the peak displacement or the peak load was affected by each type of cyclic loading to a significantly greater degree in the knees with the tendon/Endobutton procedure than in the knees reconstructed with the other two procedures. Conclusions: Plastic deformation occurred more easily during cyclic loading in the knees with the tendon/Endobutton reconstruction than in the knees with the tendon-bone reconstructions. Clinical Relevance: When the tendon/Endobutton reconstruction is used, a longer period of postoperative immobilization is necessary.
Topical Nitric Oxide Application in the Treatment of Chronic Extensor Tendinosis at the Elbow
Authors: Paoloni Justin A. , Appleyard Richard C. , Nelson Janis , Murrell George A. C. 
Published: July 2017

Background: Extensor tendinosis (“tennis elbow”) is a degenerative overuse tendinopathy of the wrist extensors at their attachment to the lateral humeral epicondyle. No treatment has been universally successful. Topical application of nitric oxide has been used effectively to treat fractures and cutaneous wounds in animal models, presumably by stimulation of collagen synthesis in fibroblasts. Purpose: To determine whether topical nitric oxide can improve outcome of patients with extensor tendinosis. Study Design: Prospective, randomized, double-blinded clinical trial. Methods: Eighty-six patients with extensor tendinosis were randomized into two equal groups; both were instructed to perform a standard tendon rehabilitation program. One group received an active glyceryl trinitrate transdermal patch, and the other group received a placebo patch. Results: Patients in the glyceryl trinitrate group had significantly reduced elbow pain with activity at 2 weeks, reduced epicondylar tenderness at 6 and 12 weeks, and an increase in wrist extensor mean peak force and total work at 24 weeks. At 6 months, 81% of treated patients were asymptomatic during activities of daily living, compared with 60% of patients who had tendon rehabilitation alone. Conclusions: Application of topical nitric oxide improved early pain with activity, late functional measures, and outcomes of patients with extensor tendinosis.
Stress Injuries to Bone in College Athletes
Authors: Arendt Elizabeth , Agel Julie , Heikes Christie , Griffiths Harry 
Published: July 2017

Background No comprehensive studies have been published on stress injuries to bone in college athletes. Purpose To review, in a college athlete population, the epidemiologic aspects of stress injuries to bone, and to examine a subset of patients who were treated with a uniform protocol for return to activities, with magnetic resonance imaging as the primary tool for diagnosis. Study Type Retrospective review. Methods Ten years of medical records from a Division I college institution were reviewed. Location and grade of stress injury to bone and duration of disability were recorded. All injured athletes followed the same treatment program, with the exception of football players, who were excluded from the return to sport analyses. Results Seventy-four athletes had lower extremity symptoms consistent with stress injury to bone. Diagnosis was confirmed in 68 of these athletes, 61 via magnetic resonance imaging, 6 via positive radiographs only, and 1 via bone scan only. Distance runners accounted for the most stress injuries to bone for both men and women. The tibia (37%) was the most frequently involved bone; however, as an anatomic region, the foot (44%) was the site of the most stress injuries. There was a significant correlation between grade of injury and time to full return to activity. Conclusions The grading system used at this institution is a standardized tool that can be used to predict time to return to sport. A standardized rehabilitation protocol allowed for an appropriate plan to return the athletes to pain-free competition.