bluuebunny/crossref_metadata_2025 huggingface dataset:
The Impact of China's ‘One-Child’ Policy on the Educational Attainment of Adolescents
Authors: Beal-Hodges Mary , Loh Chung-Ping , Stranahan Harriet
Published: July 2017

In January 1979 the Chinese government implemented a highly controversial ‘one-child’ policy that set strict limits to the number of children that each couple is allowed to have. The purpose of this study is to investigate the impact of China's ‘one-child’ policy on educational attainment. This study uses data from multiple waves of the China Health and Nutrition Survey on children ages 11–21 that were born both before (pre-cohort) and after (post-cohort) the implementation of the ‘one-child’ policy. A multi-level mixed effects model is used to determine which household, community and demographic factors impact the educational attainment and progress of Chinese children. The results suggest that more lax enforcement of the ‘one-child’ policy through a ‘girl-exception’ or ‘two-child’ policy has resulted in lower rates of growth in educational attainment and lower overall levels of education for older children. The findings also show that children in communities with the ‘one-child’ subsidy have significantly higher rates of growth in educational attainment and more years of overall education for older children.
Foreign Direct Investment in the UK: Flows, Attitudes, and Implications+
Authors: Capie Forrest , Wood Geoffrey , Sensenbrenner Frank
Published: July 2017

Foreign Investment, both direct and portfolio, is a much discussed subject throughout the world. There are substantial measurement problems, but the attention does not generally focus on these. Rather the attention is on its effects. In the context of developing countries, there is much discussion of whether the investment is destabilising, producing financial instability and maybe even financial crises.

This is not a focus of concern in developing countries. But there is often concern there also. Fears are expressed over the dangers such investment creates for jobs, innovation, research and perhaps growth. The theme of this paper is that while such fears seem to be felt in many EU countries, they are generally absent in the UK. We document this and set out the scale of investment flows into UK, before turning to explanation of the UK attitude.

Our conclusion is that the attitude is in good part a result of the UK system of corporate governance. This separates ownership and control to a much greater degree than is the case in the countries of Continental Europe, and, by separating them, makes many of the usual fears over foreign investment unnecessary, and indeed irrelevant.

This, we suggest, has implications for the future pattern of investment flows in the EU.
Overcoming Positivism in Economics: Amartya Sen’s Project of Infusing Ethics into Economics
Authors: Alvey James E.
Published: July 2017

Logical Positivism, which arose in philosophy early in the twentieth century, proclaimed the sharp distinction between facts and values. Despite objections at the time, positivism was imported into economics in the 1930s. Over time, objections lessened; economics was transformed and ethical considerations were driven out of its core. In the 1950s, debates about positivism arose within the discipline which had exported it. According to the American philosopher Hilary Putnam, the fact/value distinction is now discredited in philosophy. If that is so, the methodological foundations of contemporary economics are also discredited.

This paper examines Amartya Sen’s moral science of economics. First, it presents his historical account of the connections between economics and ethics. Sen claims that there was a close connection between the two until positivism was imported. Second, it sketches some of Sen’s ethical objections to modern economics, which is still suffering from positivism. Finally, it lays out some of his ideas on how economics can be returned to an ethical path. Once the ground has been cleared of positivism, ethics can re-emerge in economics in various ways. One path has been marked out by Sen.
Inverting Economic Imperialism: The Philosophical Roots of Ethical Controversies in Economics
Authors: Duhs Alan
Published: July 2017

Whereas economics is sometimes presented as the social science and indeed as imperialistic social science, the argument here is quite opposite. It is in fact economics itself which has been colonised by one or another political philosophy. Different schools of economic thought rest their foundations in different political and social philosophies, and this causes their proponents to orient their policy recommendations around differing definitions of ‘freedom’, ‘rationality’, ‘equality of opportunity’ and teleology. It is the a prioris of their implicit philosophies which gives distinctive character to their respective economic theories, and which define their approaches to ethical controversies in economics.

Three broad schools of thought are identified in what follows. Chicago School economic imperialists base their response to questions of values and ethics in economics on the underlying philosophy of libertarianism. That philosophy is unacceptable to institutionalist economists, however, since for them people are not meaningfully free to do as they please, unless they are already free from various external constraints. A third set of economists, dubbed radicals, reject the conception of the nature of mankind which is implicit in orthodox economics, and consequently adopt a different view towards values and ethics in economics via their commitment to a different understanding of teleology, rationality and the conception of scientific method.
Book Review: China and the Global Energy Crisis – Development and Prospects for China’s Oil and Natural Gas
Authors: Curtin J. Sean
Published: July 2017

China and the Global Energy Crisis – Development and Prospects for China’s Oil and Natural Gas, by Tatsu Kambara and Christopher Howe, Edward Elgar publishing, 2007, 160 pages. ISBN-13: 9781845429669
What Drives Military Expenditure? A South African Study
Authors: Harris Geoff
Published: July 2017

Two facts point to the need to better understand military expenditure allocations in developing countries. The first is that the number and intensity of armed conflicts worldwide have fallen consistently and significantly since 1990 and in sub-Saharan Africa since 1999. World military expenditure fell in real terms during the 1990s but has increased since 1999 and South Africa’s milex has mirrored these movements. The second is that studies which have attempted to explain milex using standard economic techniques typically explain only about half of the differences between countries. However, some potentially influential variables are not amenable to regression analysis and this article employs additional data drawn from interviews with key informants and secondary sources. It finds that the procedures used to decide on the level and composition of South Africa’s milex are clearly formulated, transparent and are adhered to with respect to recurrent expenditures. However, recent military procurement history reveals increasing Cabinet authoritarianism, a lack of transparency, significant opportunities for corruption and, arguably, inappropriate decisions.
Women’s Dignity is the Wealth of Yuchitan (Oaxaca, Mexico)
Authors: Bennholdt-Thomsen Veronika
Published: July 2017

Mexico actually is suffering from a severe economic crisis, expressed in a drastic fall in real wages, an extremely high rate of inflation, daily worsening exchange rates for the peso and the following process of general impoverization with the malnutrition of the mass of the population.

In Yuchitan, a middle-sized Zapotacan town on the Isthmus of Tehuantepec in the south of Mexico, however, these effects of the crisis are not being felt. In this article1 we attempt to explain why people in Yuchitan continue to be as well fed in the same manner to which they are accustomed, holding popular fiestas which are as numerous as before and as well provided with music, beer and food.

We maintain that Yuchitan is spared from suffering the general trend of the impoverization of Mexico at large due to the economic crisis because of the unique social position and prestige of women there. Human dignity often seen by society as immaterial has important material consequences affecting the economic. Dignity indeed is not only an ideal but has material manifestations. This knowledge is becoming more acceptable in the social sciences. A growing number of authors argue that the pauperization of large segments of the population particularly in Third World countries is not because of the lack of support in terms of financial assistance or foodstuffs. Nor is it a result of the lack of integration into the world market, as the theory of unequal exchange demonstrates. Neither is it attributable to the lack of identification with western entrepreneurial ideals or the lack of a need to achieve. On the contrary, due to the growing imitation of western patterns of behaviour, of organization, production and consumption enforced on colonial people by mechanisms as described by Fanon in Black Skin, White Mask (1952), many people have lost their self confidence and traditional knowledge which enabled them to live from their own resources and in harmony with their own surrounding nature. Hunger is a consequence of the violent destruction of these people’s ethnic, racial and sexual identity which constitutes dignity.
The Development of Pneumostrongylus tenuis in the Central Nervous System of White-tailed Deer
Authors: Anderson Roy C.
Published: July 2017

The central nervous systems of five fawns (Odocoileus virginianus borealis), infected experimentally with Pneumostrongylus tenuis, were studied histologically 10, 20, 25, 30, and 40 days after infection. In the 10–30 day fawns young developing worms were found in dorsal horns of the grey matter of all regions of the spinal cord. A few worms were found in white matter and in the medulla oblongata. In the fawn autopsied 40 days after infection all but one of about 25 worms found were in the subdural space.

Worms in the grey matter usually lay in cell-free tunnels surrounded by compressed neural tissue. There was little reaction of, or cellular infiltration in, surrounding tissue. Malacia was absent in all parts of grey matter. The central canal was normal and the brain, other than the medulla oblongata, was not involved. In the white matter, scattered single myelin sheath degeneration as well as degeneration and disappearance of axis cylinders were common. Occasionally there were tiny malacic areas in white matter, especially near worms. Infiltrations of eosinophils, lymphocytes, and plasma cells were commonly observed in and on the dura mater, the epineurium, ganglion capsules, and other tissues of the epidural space.

The relative dearth of histopathologic findings helps to explain the rarity and slightness of neurologic signs in infected fawns and is indicative perhaps of a long and well established host-parasite relationship. This is in contrast to the situation in moose (Alces a. americana) where severe traumatic damage to the spinal cord by P. tenuis is associated with ataxia and paralysis.
Osteitis Deformans in a Macaque (Macaca mulatta)
Authors: Hughes H. C. , Lang C. M.
Published: July 2017

The course of an illness that resembled osteitis deformans was followed with radiographs and clinical chemistry for 10 months after onset in an adult male macaque. Radiographically, the appendicular bones had thickened cortices, coarse trabeculae, and osteolysis. Serum calcium, phosphorus, and alkaline phosphatase were elevated. Histologically, the long bones of the limbs and calvarium showed the mosaic pattern characteristic of osteitis deformans.
Pathology of Neonatal Calf Diarrhea Induced by a Reo-Like Virus
Authors: Mebus C. A. , Stair E. L. , Underdahl N. R. , Twiehaus M. J.
Published: July 2017

Gross, immunofluorescent, and light microscopic findings in seven gnotobiotic calves inoculated orally with a Reo-like neonatal calf diarrhea virus were compared to findings in three control gnotobiotic calves. Neonatal calf diarrhea virus infected primarily the villous epithelium of the small intestine. Calves examined within 1.5 h after onset of diarrhea had tall columnar immunofluorescent villous epithelial cells in the middle and lower small intestine. Calves examined 2–4.5 h after onset of diarrhea had cuboidal to squamous villous epithelial cells and an increase in reticulum-like cells in the villous lamina propria of the middle and lower small intestine. Viral tilers were 106 and 108 in colonic contents from two calves inoculated with cell-culture-adapted virus and necropsied, respectively, 2 and 6 h after onset of diarrhea.
Ultrastructural Changes in Bovine Lingual Epithelium Infected with Vesicular Stomatitis Virus
Authors: Proctor S. J. , Sherman K. C.
Published: July 2017

Vesicular stomatitis virus was inoculated into the dorsal lingual epithelium of three cows. The reaction that developed in 72 h was characterized by severe acute diffuse glossitis with intercellular edema and necrosis of keratinocytes. Virions budded from the plasma membrane and were in the intercellular spaces. Reduplication of desmosomes was a prominent alteration, and normal desmosomes were within the cytoplasm. Intracytoplasmic desmosomes appeared to be formed by endocytosis after breaks occurred in the plasma membrane of one cell; endocytosis of loops of plasma membrane containing desmosomes; and formation of desmosomes on invagination of the plasma membrane.
Systemische Haut- und Unterhautamyloidose beim Pferd
Authors: Stünzi H. , Ehrensperger F. , Wild P. , Leemann W.
Published: July 2017

A 9-year-old horse had numerous firm, painless nodules of the skin and subcutis. Moderately vascular granulation tissue with numerous uni- or multinuclear reticuloendothelial cells was in the nodules and the regional lymph nodes but not in the viscera. By using special stains and electron microscopy, widespread amyloid deposits, mainly in the cytoplasm of reticuloendothelial cells, were identified. Amyloid was probably produced within the reticuloendothelial cells, then expelled from the dying cell and deposited in the intercellular space.
Glomerular Disease in Captive Galagos
Authors: Burkholder Peter M.
Published: July 2017

A captive colony of galagos that for several years lived under poor housing conditions and suffered a variety of chronic illnesses showed a high incidence of renal glomerular disease. Several patterns of glomerular disease were seen: four types of proliferative lesions included a mild stalk glomerulitis, more severe stalk-lobular proliferative glomerulonephritis, diffuse proliferative glomerulonephritis, and diffuse proliferative and sclerotic glomerulonephritis; and a form of glomerular capillary basement membrane thickening. Glomerular localization of immunoglobulin and the third component of complement as well as some unusual ultrastructural observations in diffuse proliferative and sclerotic glomerulonephritis suggest an immunopathogenesis for this disease.
Nephritis and Hemolytic Anemia in Owl Monkeys (Aotus trivirgatus)
Authors: Chalifoux L. V. , Bronson R. T. , Sehgal P. , Blake B. J. , King N. W.
Published: July 2017

The two most common diseases of captive owl monkeys (Aotus trivirgatus) are hemolytic anemia and glomerulonephritis. The anemia is characterized by total red blood cell counts between 0.45 and 3.44 × 106/μl, hemoglobin values as low as 1.0 g/dl, and many circulating nucleated red blood cells. Centrilobular necrosis in the liver, extramedullary hematopoiesis in liver and spleen, and hemoglobin casts in kidney tubules are prominent histologic features. Hemosiderin and lipofuscin often are found in liver, spleen, kidney and lymph nodes. Microthrombi and microinfarcts sometimes are scattered throughout the brain. Glomerular lesions in Aotus have been described previously and are characterized by increased numbers of mesangial cells and matrix, glomerulosclerosis and electron dense deposits in basement membranes. Lymphocytes, plasma cells and eosinophils frequently are present in the interstitium. In the early stages the cellular infiltrate is periglomerular. The foci then grow to encompass adjacent glomeruli and tubules. Finally, large portions of the kidney are affected and connective tissue proliferates. The incidence of extramedullary hematopoiesis in the liver correlated significantly with that of interstitial nephritis (0.001 < p < 0.01) but not with glomerular lesions. The two kidney lesions, glomerulonephritis and interstitial nephritis, correlated strongly in incidence. They also were found with equal frequency in 87 monkeys with clinical evidence of anemia. This analysis indicates that there may be no common pathogenesis of the hematologic and renal abnormalities as seen in certain autoimmune diseases. However, there could be complex interactions between two or more disease mechanisms that account for the various manifestations of disease.
Chronic Tubulointerstitial Nephritis and Wasting Disease in Marmosets (Callithrix jacchus)
Authors: Brack M. , Rothe H.
Published: July 2017

Six marmosets (Callithrix jacchus). 20 months to 16 years old, died from a disease characterized by weakness and paralysis of the hind legs, weight loss, anemia and transient diarrhea. The lesions most prominent at necropsy were subacute to chronic tubulointerstitial nephritis, subacute to chronic pancreatitis, and generalized hemosiderosis. Chronic protein deficiency is believed to be the underlying pathogenic mechanism, since the diet contained no more than 15% animal protein during the last two years, and increasing the amount of protein was accompanied by disappearance of the syndrome.
Renal Pathology of Catheterized Baboons (Papio cynocephalus)
Authors: Heidel J. R. , Giddens W. E. , Boyce J. T.
Published: July 2017

Renal disease was found at necropsy in 27 of 60 catheterized baboons (Papio cynocephalus). Primary diagnoses were infarcts in eight baboons, septic embolic nephritis in four, and mesangioproliferative glomerulonephritis in 15. Infarcts and septic embolic nephritis are multifocal renal diseases; mesangioproliferative glomerulonephritis is diffuse, progressive, and often accompanied by severe proteinuria, hypoalbuminemia (<3 g/dl), and generalized edema. Five of the 15 baboons with glomerulonephritis also developed uremia and died of renal failure. Ten baboons with glomerulonephritis were given microbiological examination during their clinical course. Bacteria were isolated from the peripheral blood of eight baboons and from the catheter itself in two. The organisms isolated (in decreasing order of frequency) were Herellea sp., Streptococcus sp., Klebsiella sp., Staphylococcus sp., and Providencia sp. Prospective immunofluorescence studies were done on frozen sections from six catheterized baboons with glomerulonephritis and two uncatheterized controls. There were granular deposits of IgG in all six, IgM in five, C3 in four, and IgA and C4 in two. In the controls, only trace amounts of IgM were seen in one animal. The amount of IgG deposited in the glomeruli correlated with the severity of the glomerulonephritis. Bacterial antigens were found by immunofluorescence in glomeruli of three of five baboons examined. Glomerulonephritis in these baboons seems to be immunologically mediated, and in origin, pathogenesis and morphologic expression resembles shunt nephritis in humans with infected indwelling shunts and catheters.
Cortical Spreading Depression in Migraine
Authors: Lauritzen M
Published: July 2017

Cortical spreading depression (CSD) is associated with a dramatic failure of brain ion homeostasis as well as efflux of excitatory amino acids from nerve cells and increased energy metabolism. There is strong clinical and experimental evidence to suggest that CSD is involved in the mechanism of migraine. This paper will, based on the experience related to the detection of CSD in humans, discuss pitfalls and possible strategies for detection of CSD in man. Development of reliable methods for detection of CSD in humans will determine the extent to which the large body of experimental findings from animal studies of CSD can be applied to the investigation and treatment of human brain disease. The paper is based on the experience that has been gained from two decades of studies of CSD in relation to clinical neurological diseases.
Management of Severe Lower Abdominal or Inguinal Pain in High-Performance Athletes
Authors: Meyers William C. , Foley David P. , Garrett William E. , Lohnes John H. , Mandlebaum Bert R.
Published: July 2017

The purpose of this study was to gain insight into the pathophysiologic processes of severe lower-abdominal or inguinal pain in high-performance athletes. We evaluated 276 patients; 175 underwent pelvic floor repairs. Of the 157 athletes who had not undergone previous surgery, 124 (79%) participated at a professional or other highly competitive level, and 138 patients (88%) had adductor pain that accompanied the lower-abdominal or inguinal pain. More patients underwent related adductor releases during the later operative period in the series. Evaluation revealed 38 other abnormalities, including severe hip problems and malignancies. There were 152 athletes (97%) who returned to previous levels of performance. The syndrome was uncommon in women and the results were less predictable in nonathletes. A distinct syndrome of lower-abdominal/adductor pain in male athletes appears correctable by a procedure designed to strengthen the anterior pelvic floor. The location and pattern of pain and the operative success suggest the cause to be a combination of abdominal hyperextension and thigh hyperabduction, with the pivot point being the pubic symphysis. Diagnosis of “athletic pubalgia” and surgery should be limited to a select group of high-performance athletes. The consideration of other causes of groin pain in the patient is critical.
Injury Risk Factors among Telemark Skiers
Authors: Tuggy Michael L. , Ong Ric
Published: July 2017

We performed a population survey of telemark skiers over two ski seasons to determine specific risk factors for injury. The survey inquired about the skier's sex, experience, equipment used, injuries, and number of days skied in each season. The respondents completed the surveys whether or not they were injured while skiing. We received 677 responses from telemark skiing clubs, with 19,962 skier-days of data. The number of self-reported injuries was 178, for an overall self-reported injury rate of 8.9 per 1000 skier-days. Knee injuries (N 48) were the most common injury (27%), followed by thumb (N 32, 18%) and shoulder (N 21, 12%) injuries. Specific risk factors for injury were identified with multivariate regression and survival analysis. The skill level of the skier had a significant injury-sparing effect, as did the use of plastic telemark boots. The protective effect of the plastic boots was likely due to the increased stability they provided compared with traditional leather boots. There were fewer knee injuries with the recently available releasable bindings for telemark skis. Sex and age had no significant impact on injury rates in this study population. As all reported deaths associated with telemark sking were due to environmental hazards, skiers must continue to pay close attention to these hazards in the backcountry.
The Effect of a Geographic Lateral Bone Bruise on Knee Inflammation after Acute Anterior Cruciate Ligament Rupture
Authors: Johnson Darren L. , Bealle David P. , Brand Jefferson C. , Nyland John , Caborn David N. M.
Published: July 2017

We prospectively evaluated 40 patients who had knee inflammation after isolated anterior cruciate ligament rupture with or without an associated “geographic” bone bruise/subchondral fracture of the lateral femoral condyle. All patients with acute ruptures documented by magnetic resonance imaging within 1 week of injury were evaluated for a geographic bone bruise/subchondral fracture of the lateral femoral condyle. Two groups of 20 patients each (bone bruise versus no bone bruise) were then enrolled. Variables measured at 1, 2, 3, and 4 weeks after injury included pain, range of motion, effusion, and number of days with an antalgic gait. Patients with a bone bruise had increased size and duration of effusion, increased number of days required to nonantalgic gait without external aids, increased days to achieve normal range of motion, and increased pain scores at measured time intervals. This study confirms results of previous clinical and histologic studies showing an associated articular cartilage lesion, otherwise known as bone bruise/subchondral fracture, is clinically significant. There appears to be an association between a geographic bone bruise and increased disability in patients with acute anterior cruciate ligament ruptures. Patients with a geographic bone bruise may require longer to reach normal homeostasis (range of motion, pain, neuromuscular control) before undergoing anterior cruciate ligament reconstruction.
Ligamentous Restraints to External Rotation of the Humerus in the Late-Cocking Phase of Throwing
Authors: Kuhn John E. , Bey Michael J. , Huston Laura J. , Blasier Ralph B. , Soslowsky Louis J.
Published: July 2017

The late-cocking phase of throwing is characterized by extreme external rotation of the abducted arm; repeated stress in this position is a potential source of glenohumeral joint laxity. To determine the ligamentous restraints for external rotation in this position, 20 cadaver shoulders (mean age, 65 16 years) were dissected, leaving the rotator cuff tendons, coracoacromial ligament, glenohumeral capsule and ligaments, and coracohumeral ligament intact. The combined superior and middle glenohumeral ligaments, anterior band of the inferior glenohumeral ligament, and the entire inferior glenohumeral ligament were marked with sutures during arthroscopy. Specimens were mounted in a testing apparatus to simulate the late-cocking position. Forces of 22 N were applied to each of the rotator cuff tendons. An external rotation torque (0.06 N m/sec to a peak of 3.4 N m) was applied to the humerus of each specimen with the capsule intact and again after a single randomly chosen ligament was cut (N 5 in each group). Cutting the entire inferior glenohumeral ligament resulted in the greatest increase in external rotation (10.2° 4.9°). This was not significantly different from sectioning the coracohumeral ligament (8.6° 7.3°). The anterior band of the inferior glenohumeral ligament (2.7° 1.5°) and the superior and middle glenohumeral ligaments (0.7° 0.3°) were significantly less important in limiting external rotation.
Association of Burners with Cervical Canal and Foraminal Stenosis
Authors: Kelly John D. , Aliquo David , Sitler Michael R. , Odgers Charles , Moyer Ray A.
Published: July 2017

The purpose of this study was to determine whether the burner phenomenon is associated with cervical canal and foraminal stenosis in a scholastic population. Lateral cervical radiographs were reviewed for 64 athletes, 15 to 18 years of age, who had sustained at least one burner. Controls consisted of age-matched athletes who had sustained head or neck trauma without evidence of the burner phenomenon (N 32). Pavlov ratios were calculated for levels C-3 through C-6; both mean minimum and mean average ratios were determined. Available oblique radiographs from both the study (N 31) and control (N 15) groups were then used to calculate the foramen/vertebral body ratio—a measure of relative foraminal height. Significant differences were found between the burner and control groups for the mean minimum and mean average Pavlov ratios and foramen/vertebral body ratios. Scholastic athletes sustaining the burner phenomenon have an increased risk of cervical canal and foraminal stenosis as measured by the Pavlov and foramen/vertebral body ratios, respectively. The foramen/vertebral body ratio is an easily reproducible and reliable means of assessing foraminal dimensions from oblique radiographs and controls for x-ray magnification and rotation. Foraminal stenosis assessment may prove useful in predicting burner risk, especially in athletes with extension-compression injuries.
Comparison of Soccer Shin Guards in Preventing Tibia Fracture
Authors: Francisco Anthony C. , Nightingale Roger W. , Guilak Farshid , Glisson Richard R. , Garrett William E.
Published: July 2017

The goal of this study was to evaluate the effectiveness of a number of shin guards in protecting against tibia fracture in soccer players. A secondary purpose was to determine the relationship between the material and structural differences in shin guard design and the protection provided. Twenty-three commercially available shin guards were tested on a model leg containing a synthetic tibia that had been calibrated against human cadaver specimens. Each guard was categorized into one of four material types: plastic (N 9), fiberglass (N 6), compressed air (N 4), and Kevlar (N 4). The maximum combined force at the ends of the tibia, the principal strain on the posterior side of the tibia, and the contact time of the impact were measured using a drop track impact simulation. Shin guards provided significant protection from tibia fracture at all drop heights. The average guard reduced force by 11% to 17% and strain by 45% to 51% compared with the unguarded leg. At the higher drop heights, material composition and structural characteristics of the shin guards showed significant differences in protective abilities. These findings indicate that all shin guards provide some measure of protection against tibia fracture, although the level of protection may vary significantly among the different guards.
Results of Anterior Cruciate Ligament Reconstruction Based on Meniscus and Articular Cartilage Status at the Time of Surgery
Authors: Shelbourne K. Donald , Gray Tinker
Published: July 2017

We sought to determine how the status of the meniscus and articular cartilage observed at the time of anterior cruciate ligament reconstruction affects results at 5 to 15 years after surgery. Objective follow-up was obtained on 482 patients at a mean of 7.6 years after surgery. Subjective follow-up was obtained on 928 patients at a mean of 8.6 years after surgery. Patients with both menisci present had significantly better KT-1000 arthrometer scores than did patients with any part of the medial or both menisci removed. Stepwise regression analyses determined that a partial or total medial or lateral meniscectomy and damaged articular cartilage significantly lowered the final subjective total score. Patients with both menisci present and normal articular cartilage had a mean subjective total score of 94, and 97% had normal or near normal radiographic ratings on a weightbearing 45° posteroanterior radiographs. The overall International Knee Documentation Committee rating was normal or nearly normal for 204 of 235 patients (87%) with both menisci present, 52 of 74 patients (70%) with partial or total lateral meniscectomies, 71 of 113 patients (63%) with partial or total medial meniscectomies, and 36 of 60 patients (60%) with both menisci removed. We concluded that the long-term subjective and objective results of a successful anterior cruciate ligament reconstruction are affected by the status of the menisci and articular surface.
Effects of Protective Knee Bracing on Speed and Agility
Authors: Greene David L. , Hamson Karl R. , Bay R. Curtis , Bryce Chris D.
Published: July 2017

We evaluated the effects of prophylactic knee braces on athlete speed and agility, as well as brace tendency to migrate. Thirty college football players in full gear ran a 40-yard dash and a four-cone agility drill wearing braces on both knees or no brace (control). Braces included the DonJoy Legend, Breg Tradition, OMNI-AKS 101W, McDavid Knee Guard, and models 1 and 2 of the Air Armor Knee and Thigh Protection System. Brace migration and subjective measures were recorded after each trial. In the 40-yard dash, times using Air Armor 1 and OMNI did not differ significantly from control. Times with other braces were significantly slower. In the four-cone drill, only the Breg times were significantly slower than control. The Air Armor 1 and McDavid braces showed significantly less superior/inferior migration in the 40-yard dash than other braces. In the four-cone drill, the Air Armor 1 and 2 showed significantly less superior/inferior migration than other braces. These findings indicate that selected knee braces do not significantly reduce speed or agility. Braces showed a variable tendency to migrate, which could affect their protective function and athlete performance. This information will help athletes and coaches decide about knee-brace use during sports; studies are needed regarding whether braces protect against knee injury. This study does not constitute an endorsement of knee-brace use or efficacy.
The Relationship of the Infrapatellar Branches of the Saphenous Nerve to Arthroscopy Portals and Incisions for Anterior Cruciate Ligament Surgery: An Anatomic Study
Authors: Tifford Craig D. , Spero Lane , Luke Timothy , Plancher Kevin D.
Published: July 2017

The purposes of this study were 1) to carefully define the anatomic distribution of the infrapatellar branches of the saphenous nerve, 2) to provide the surgeon with reliable parameters for where the nerve is most commonly encountered, and 3) to provide specific surgical recommendations to minimize the risk of nerve injury. To accomplish these goals, we dissected 20 cadaveric, fresh-frozen, matched-pair knees. Calipers were used to measure the distance from the nerve to three clinically relevant and easily reproducible landmarks: the inferior pole of the patella, the medial border of the patella at its midpoint, and a point 2 cm medial to the patellar ligament at the level of the joint line. Distances were recorded with the knees in extension and in 90° of flexion to examine the effect of dynamic knee motion on nerve position. We consistently found two main trunks of the nerve that traverse the knee primarily in a medial to lateral but somewhat proximal to distal direction. Because of this, we recommend that incisions for arthroscopy portals be made in a horizontal fashion to decrease the likelihood of nerve injury. Measured from both the inferior pole of the patella and the medial border of the patella, the nerve moved distally with knee flexion. We therefore recommend that incisions across the anterior aspect of the knee be made with the knee in flexion. In 8 of our 20 specimens, the nerve was actually found at the landmark located 2 cm medial to the patellar ligament. This is an extremely high-risk area and should be avoided if possible.
Injuries to the Shoulder in the Throwing Athlete: Part Two: Evaluation/Treatment
Authors: Meister Keith
Published: July 2017

In part one of this three-part series (March/April 2000), I concentrated on summarizing the biomechanics of the normal throwing shoulder and the pathophysiology of injury. A classification of injury was presented that was based on the principles contained in that article. Part two of this series will focus on the evaluation and treatment of injuries, expanded from an understanding of the principles learned in part one. The ability to perform a skillful examination, and thus develop an accurate diagnosis, is the foundation for treatment. Fortunately, many difficulties encountered in a thrower's shoulder can be treated with a nonoperative approach. However, in instances where conservative measures fail, an improved understanding of the pathophysiology of injury and the development of improved surgical techniques are leading to more accurate diagnoses and more successful rates of return of the athlete to a premorbid level of activity.
Cervical Spine Alignment in the Immobilized Ice Hockey Player
Authors: LaPrade Robert F. , Schnetzler Kent A. , Broxterman Robert J. , Wentorf Fred , Wendland Erik , Gilbert Thomas J.
Published: July 2017

To determine if helmet removal causes a significant increase in lordosis of the cervical spine in ice hockey players, we radiographically assessed the position of the cervical spine in subjects immobilized to a standard spine backboard wearing shoulder pads both with and without a helmet. Ten adult male volunteers (ages, 18 to 28 years) with no previous history of cervical spine injuries were fitted with an appropriately sized ice hockey helmet and shoulder pads and immobilized in a supine position to a standard spine backboard. Computerized tomographic lateral scout scans were obtained of the cervical spine for three conditions: 1) no equipment (control), 2) helmet and shoulder pads, and 3) shoulder pads only (helmet removed). With the helmet removed and the shoulder pads remaining, a significant increase in C2 to C7 lordosis was found when compared with the other two conditions. Individual segmental measurements revealed a significant increase in cervical lordosis at the C6—7 level with the helmet removed compared with the helmet and shoulder pads condition. Our results demonstrate that the removal of an ice hockey helmet from a supine player causes a significant increase in lordosis (extension) of the cervical spine. We recommend that ice hockey helmets not be removed from injured players, with rare exceptions, because doing so results in unnecessary motion of the cervical spine.
Immediate Surgical Repair of the Medial Patellar Stabilizers for Acute Patellar Dislocation
Authors: Ahmad Christopher S. , Stein Beth E. Shubin , Matuz David , Henry Jack H.
Published: July 2017

An open surgical repair of the injured medial patellar stabilizers, including the vastus medialis obliquus muscle and the medial patellofemoral ligament, after acute patellar dislocation was studied in eight patients. At initial examination, all patients had tenderness over the adductor tubercle and a positive patellar apprehension sign. Four of eight patients had obvious ecchymosis over the adductor tubercle. Magnetic resonance imaging, diagnostic arthroscopy, and open surgical exploration documented injury to both the medial patellofemoral ligament and the origin of the vastus medialis obliquus muscle. In all patients, the torn muscle was retracted in an anterior and superior direction and an arthroscopic lateral release was performed followed by open primary repair of the medial patellofemoral ligament to the adductor tubercle and repair of the vastus medialis obliquus muscle to the adductor magnus tendon. Patients were evaluated postoperatively with the Kujala scoring questionnaire. The average follow-up was 3.0 years, with a minimum of 1.5 years. No patients experienced a recurrent dislocation. The average Kujala score was 91.9. Patients rated their return to athletic activity at an average 86% of their pre-injury level. The average subjective satisfaction was 96%. In appropriate cases of acute patellar dislocation, we recommend primary repair of the medial patellofemoral ligament and the vastus medialis obliquus muscle to avoid recurrent dislocation, chronic subluxation, pain, and disability.
Anatomy and Kinematics of the Lateral Collateral Ligament of the Knee
Authors: Meister Brad R. , Michael Stanley P. , Moyer Ray A. , Kelly John D. , Schneck Carson D.
Published: July 2017

The anatomy and kinematics of the lateral collateral ligament were studied in 10 unembalmed limbs and 20 isolated femurs and fibulas. The ligament's average overall length was 66 mm (range, 59 to 74) and the average greatest dimension of its thin middle portion was the anteroposterior dimension of 3.4 mm (range, 3 to 4). The center of the femoral attachment site was 3.7 mm posterior to the ridge of the lateral epicondyle, not at it apex. A potential radiographic technique for operatively locating the femoral attachment site to within 3 mm is described. During knee flexion in neutral rotation the distance between the femoral and fibular attachment sites of the lateral collateral ligament decreased to 88% of its value in full extension. With 6.5 N m of applied external rotation force, beyond 30° of flexion the attachment sites rapidly approximated. With the same internal rotation force, beyond 15° of flexion the attachment sites separated. From 60° to 105° they were greater than 100% of the value in full extension, suggesting significant distraction between the attachment sites. These changes correlated well with the ligament's change from an 11° posterior slope in extension to a 19° anterior slope in flexion with no applied rotation.
Dynamic Function after Anterior Cruciate Ligament Reconstruction with Autologous Patellar Tendon
Authors: Bush-Joseph Charles A. , Hurwitz Debra E. , Patel Rhohita R. , Bahrani Yersin , Garretson Ralph , Bach Bernard R. , Andriacchi Thomas P.
Published: July 2017

The purpose of this study was to dynamically assess the functional outcome of patients who had undergone successful anterior cruciate ligament reconstruction using an autologous patellar tendon technique and to determine whether their dynamic knee function was related to quadriceps and hamstring muscle strength. The knee kinematics and kinetics of 22 subjects who had undergone anterior cruciate ligament reconstruction (mean age, 27 11 years) and of 22 age- and sex-matched healthy control subjects were determined during various dynamic activities using a computerized motion analysis and force plate system. The differences in the sagittal plane angles and external moments between the two groups during light (walking), moderate (climbing and descending stairs), and higher-demand (jogging, jog and cut, jog and stop) activities were related to isokinetic strength measurements. Although patients who are asymptomatic and functioning well after anterior cruciate ligament reconstruction can perform normally in light activities, higher-demand activities reveal persistent functional adaptations that require further study.
The Effects of Time Course after Anterior Cruciate Ligament Injury in Correlation with Meniscal and Cartilage Loss
Authors: Murrell George A. C. , Maddali Sirish , Horovitz Lois , Oakley Stephen P. , Warren Russell F.
Published: July 2017

In this study, 130 consecutive patients with anterior cruciate ligament insufficiency who were undergoing ligament reconstruction underwent arthroscopic examination at the time of reconstruction, and any loss of meniscal or chondral integrity was documented in a systematic fashion. In these patients, a greater proportion of the medial meniscus was lost compared with the lateral meniscus (16% versus 5%). On average, 6 cm2 of the articular cartilage was damaged (5.2 cm 2) or lost (0.8 cm2), with the area of damage and loss greatest on the medial femoral condyle. Patients whose injuries had occurred more than 2 years before the examination had more than sixfold greater cartilage loss and damage compared with those whose injuries had occurred within the past 2 months. Meniscal loss was associated with a threefold increase in cartilage damage or loss. The group of patients with meniscal loss whose initial anterior cruciate ligament injury occurred more than 2 years before examination exhibited 18 times the amount of cartilage loss or damage as did the group that had no meniscal loss and whose injury occurred less than 1 month before examination.
Instrumented Measurement of Glenohumeral Joint Laxity and its Relationship to Passive Range of Motion and Generalized Joint Laxity
Authors: Sauers Eric L. , Borsa Paul A. , Herling Derald E. , Stanley Rick D.
Published: July 2017

The purpose of this study was to objectively characterize in vivo glenohumeral joint laxity using an instrumented shoulder arthrometer. Secondary objectives were to examine the relationship of glenohumeral joint laxity with passive range of motion and generalized joint laxity. Fifty-one recreational athletes with no history of shoulder injury or long-term participation in overhead sports participated in this study. Anterior and posterior laxity data were obtained at displacement forces of 67, 89, 111, and 134 N. Bilateral passive shoulder range of motion measures were obtained, and a modified Beighton Mobility Score was used to quantify generalized joint laxity. There were no significant differences in glenohumeral joint laxity between the right and left shoulders (P values 0.14 to 0.73). No significant differences in laxity were seen between directions (F(1,400) 1.35, P 0.25). However, significant differences were observed between force levels (F(3,400) 27.17, P <0.0001). No moderate or stronger correlations between laxity, passive range of motion, and generalized joint laxity were seen. These data confirm the presence of a wide spectrum of symmetric laxity in subjects that fails to correlate strongly with passive range of motion or generalized joint laxity.
Anterior Cruciate Ligament Reconstruction
Authors: Anderson Allen F. , Snyder Robert B. , Lipscomb A. Brant
Published: July 2017

A prospective randomized study was performed to determine the differences in results between three methods of anterior cruciate ligament reconstruction: autogenous bone-patellar tendon-bone graft (group 1), semitendinosus and gracilis tendon graft reconstruction combined with an extraarticular procedure (group 2), and semitendinosus and gracilis tendon graft reconstruction alone (group 3). Preoperatively, there were no significant differences between groups. At a mean of 35.4±11.6 months postoperatively, 102 patients returned for evaluation. International Knee Documentation Committee knee evaluation revealed no significant differences in symptoms, function, return to pre-injury activity, harvest site abnormalities, or limitation of motion between groups 1 and 3. Patients in group 2 had a higher incidence of patellofemoral crepitation and loss of motion than did patients in group 3. The mean manual maximum KT-1000 arthrometer side-to-side difference was 2.1±2.0 mm in group 1, which was statistically significantly better than the difference in group 3 (3.1±2.3 mm). Final knee rating showed that 34 of 35 patients in group 1, 23 of 34 patients in group 2, and 26 of 33 patients in group 3 had a normal or nearly normal overall knee rating. Anterior cruciate ligament reconstruction with a semitendinosus and gracilis or a patellar tendon autograft may yield similar subjective results; however, the patellar tendon autograft may provide better objective stability in the long term. In addition, there appears to be no benefit to combining an intraarticular anterior cruciate ligament reconstruction with an extraarticular procedure.
The Axial View to Measure Posterior Laxity of the Knee
Authors: Assal Mathieu , Fritschy Daniel , Stern Richard , Jakob Roland P.
Published: July 2017

Posterior laxity of the knee can be assessed clinically, but interpretation of the amount of displacement is highly subjective. Mechanical methods are more efficacious for measuring anterior laxity. Radiologic techniques are available for measurement in a lateral projection, but some variables may interfere with their accuracy. We undertook a trigonometric analysis of the axial view to confirm that it can be used to reliably measure posterior displacement. The ideal radiologic conditions consist of 80° of knee flexion in both knees maintained with a knee support and a 26° x-ray beam incidence with respect to the tibia. Although such accuracy is rarely obtained in routine clinical practice, even with a variability of 10° in the x-ray beam incidence the error factor will be less than ±10%. Such a degree of error is in the same range (±2 mm) as noted by investigators using the lateral radiograph to measure anteroposterior displacement. We believe that our study validates the use of a single axial radiograph of both knees to assess the state of the posterior cruciate ligament of an injured knee as compared with a normal knee.