Musculoskeletal injuries in real tennis.

Introduction: Real tennis is a growing, unique, and well-established sport. To date, there has been no epidemiological data on real tennis injuries. The primary aim of this retrospective study is to record the incidence and document any trends in real tennis musculoskeletal injuries, so as to improve injury awareness of common and possibly preventable injuries. Methods: A surveillance questionnaire e-mailed to 2,036 Tennis & Rackets Association members to retrospectively capture injuries sustained by amateur and professional real tennis players over their playing careers. Results: A total of 485 (438 males and 47 females) questionnaires were fully completed over 4 weeks. A total of 662 musculoskeletal injuries were recorded with a mean of 1.4 injuries per player (range 0-7). The incidence of sustaining an acute real tennis musculoskeletal injury is 0.4/1000 hrs. The three main anatomical locations reported injured were elbow 15.6% (103/662), knee 11.6% (77/662), and face 10.0% (66/662). The most common structures reported injured were muscle 24% (161/661), tendon 23.4% (155/661), ligament 7.0% (46/661), soft tissue bruising 6.5% (43/661), and eye 6.2% (41/661). The majority of the upper limb injuries were gradual onset (64.7%, 143/221), and the lower limb injuries were sudden onset (72.0%, 188/261). Conclusion: This study uniquely provides valuable preliminary data on the incidence and patterns of musculoskeletal injuries in real tennis players. In addition, it highlights a number of reported eye injuries. The study is also a benchmark for future prospective studies on academy and professional real tennis players.

The epidemiology and trends in the surgical management of calcaneal fractures in England between 2000 and 2017.

AIMS: This paper documents the epidemiology of adults (aged more than 18 years) with a calcaneal fracture who have been admitted to hospital in England since 2000. Secondary aims were to document whether publication of the United Kingdom Heel Fracture Trial (UK HeFT) influenced the proportion of patients admitted to hospital with a calcaneal fracture who underwent surgical treatment, and to determine whether there has been any recent change in the surgical technique used for these injuries. PATIENTS AND METHODS: In England, the Hospital Episode Statistics (HES) data are recorded annually. Between 2000/01 and 2016/17, the number of adults admitted to an English NHS hospital with a calcaneal fracture and whether they underwent surgical treatment was determined. RESULTS: During this 17-year period, 62 858 patients were admitted to hospital with a calcaneal fracture. The male-to-female ratio was 2.66:1. The mean annual incidence was 10.5/100 000 for men and 3.8/100 000 for women. The results of the UK HeFT were published in July 2014. The percentage of patients admitted with a calcaneal fracture undergoing internal fixation was 7.31% (3792/51 859) before and 7.38% (534/7229) after its publication. This difference was not statistically significant (p = 0.94). Since 2015, there has been a significant increase in the percentage of calcaneal fractures treated by closed reduction and internal fixation, as opposed to open reduction and internal fixation, from 7.7% (292/3792) to 13.29% (71/534) (p < 0.001). CONCLUSION: This study documents the epidemiology and trends in surgical treatment of calcaneal fractures in England. We established that surgeons did not change their practice in terms of offering surgery to these patients in response to the results of the UK HeFT. There has been a significant (p < 0.001) increase in the number of calcaneal fractures being treated surgically using less invasive procedures.

Internal fixation of femoral neck stress fractures in young female athletes with a dynamic locking plate.

PURPOSE: Displaced stress fractures of the femoral neck in young female athletes are a rare but a difficult injury to treat with a favourable outcome, as there is a reported high incidence of avascular necrosis. Traditionally they are internally fixed with either cannulated screws or a sliding hip screw. Our study aims to highlight the Targon Femoral Neck (FN, B-Braun, Aesculap Inc, Germany) implant as a safe alternative for fixation of these injuries. METHODS: Three consecutive young female recreational athletes were reviewed from our institution with a displaced stress fracture of the femoral neck treated with the dynamic locking plate. RESULTS: Two patients achieved good results with full union and no complications. One patient had a poor result as she developed avascular necrosis 5 months post-operatively requiring revision to a total hip arthroplasty. CONCLUSION: Our study highlights the Targon FN implant is a safe alternative for internal fixation of displaced stress fractures of the femoral neck in young female recreational athletes.

Surgical excision of ununited hook of hamate fractures via the carpal tunnel approach.

INTRODUCTION: Direct excision of a symptomatic ununited hook of hamate fracture is the gold standard, most frequently via a Guyon space approach. The open carpal tunnel approach is another option, which has not previously been commonly considered and not reported in a peer review journal. Our study aims to highlight the carpal tunnel approach as a successful technique in a consecutive series of ununited hook of hamate fractures. PATIENTS AND METHODS: Seven patients (all male and mean age 30.7 years) were reviewed with symptomatic ununited fractures following a period of cast immobilization. All the patients operated on underwent excision of the hook of hamate fragment via the open carpal tunnel approach. RESULTS: All patients successfully returned to their pre-injury level of functioning after 8-12 weeks and there were no complications. CONCLUSIONS: Our study highlights the open carpal tunnel approach as a successful technique for open excision of symptomatic ununited hook of hamate fractures, because of its familiarity, ease of performance, excellent visualization and low morbidity. Level of Evidence IV Case Series.

Response of cricket and spider motion-sensing hairs to airflow pulsations.

Closed-form analytical solutions are presented for the angular displacement, velocity and acceleration of motion-sensing filiform hairs exposed to airflow pulsations of short time duration. The specific situations of interest correspond to a spider intentionally moving towards a cricket, or an insect unintentionally moving towards or flying past a spider. The trichobothria of the spider Cupiennius salei and the cercal hairs of the cricket Gryllus bimaculatus are explored. Guided by earlier work, the spatial characteristics of the velocity field due to a flow pulsation are approximated by the local incompressible flow field due to a moving sphere. This spatial field is everywhere modulated in time by a Gaussian function represented by the summation of an infinite Fourier series, thus allowing an exploration of the spectral dependence of hair motion. Owing to their smaller total inertia, torsional restoring constant and total damping constant, short hairs are found to be significantly more responsive than long hairs to a flow pulsation. It is also found that the spider trichobothria are underdamped, while the cercal hairs of the cricket are overdamped. As a consequence, the spider hairs are more responsive to sudden air motions. Analysis shows that while two spiders of different characteristic sizes and lunge velocities can generate pulsations with comparable energy content, the associated velocity fields display different patterns of spatial decay with distance from the pulsation source. As a consequence, a small spider lunging at a high velocity generates a smaller telltale far-field velocity signal than a larger spider lunging at a lower velocity. The results obtained are in broad agreement with several of the observations and conclusions derived from combined flow and behavioural experiments performed by Casas et al. for running spiders, and by Dangles et al. for spiders and a physical model of spiders lunging at crickets.

Thermal energy conduction in a honey bee comb due to cell-heating bees.

Theoretical analysis and numerical calculations are performed to characterize the unsteady two-dimensional conduction of thermal energy in an idealized honey bee comb. The situation explored corresponds to a comb containing a number of brood cells occupied by pupae. These cells are surrounded by other cells containing pollen which, in turn, are surrounded (above) by cells containing honey and (below) by vacant cells containing air. Up to five vacant cells in the brood region can be occupied by cell-heating bees which, through the isometrical contraction of their flight muscles, can generate sufficient energy to raise their body temperatures by a few degrees. In this way, the cell-heating bees alter the heat flux and temperature distributions in the brood region so as to maintain conditions that benefit the pupae. The calculations show that the number of cell-heating bees significantly affects the magnitude, time rate of change, and spatial distribution of temperature throughout the comb. They also reveal a vertically aligned asymmetry in the spatial distribution of temperature that is due to the large heat capacity and thermal conductivity of honey relative to air, whereby air-filled cells experience larger temperature increases than honey-filled cells. Analysis shows that convection and radiation represent negligible modes of thermal energy transfer at all levels in the problem considered. Also, because of its small thickness, the wax wall of a comb cell simultaneously presents negligible resistance to conduction heat transfer normal to it and very large resistance along it. As a consequence the walls of a cell play no thermal role, but simply serve as mechanical supports for the materials they contain.

Cholesterol accumulates in senile plaques of Alzheimer disease patients and in transgenic APP(SW) mice.

Mounting evidence suggests that cholesterol may contribute to the pathogenesis of Alzheimer disease (AD). We examined whether cholesterol might be present in senile plaques, a hallmark neuropathological feature of AD. We employed 2 different fluorometric-staining techniques (filipin staining and an enzymatic technique) for the determination of cholesterol in brains of postmortem confirmed AD patients and in nondemented, age-matched histopathologically normal controls. AD patient brains showed abnormal accumulation of cholesterol in congophilic/birefringent dense cores of senile plaques that was essentially absent in histopathologically normal controls. To determine whether increased senile plaque-associated cholesterol occurred generally in all plaques or was restricted to a specific subset, quantitative analysis was performed. Data indicate abnormal accumulation of cholesterol in cores of mature plaques but not in diffuse or immature plaques. Additionally, transgenic mice that overexpress the "Swedish" amyloid precursor protein (Tg APP(SW), line 2576) exhibited a similar pattern of abnormal cholesterol accumulation in mature, congophilic amyloid plaques at 24 months of age that was absent in their control littermates or in 8-month-old Tg APP(SW) mice (an age prior to amyloid deposition). Taken together, our results imply a link between cholesterol and AD pathogenesis and suggest that cholesterol plays an important role in the formation and/or progression of senile plaques.

Women's vulnerability to sexual assault from adolescence to young adulthood.

PURPOSE: To study the vulnerability to sexual assault among undergraduate women. METHODS: The respondents were demographically representative of undergraduate women in state-supported universities in the United States. Participants (N = 1569) were surveyed using the Sexual Experiences Survey at the beginning and end of their 1st year and at the end of each of the next 3 years of their undergraduate career. Survival analysis was used to determine the risk of initial victimization during specific time intervals from the age of 14 years through the collegiate years as a function of prior victimization. Odds analyses were used to analyze the main and interactive effects of victimization at prior time periods on the probability of victimization at subsequent time periods. RESULTS: Victimization before the age of 14 years almost doubled the risk of later adolescent victimization (1.8). Furthermore, for those with and without childhood victimization, the risk of an initial sexual assault after the age of 14 years occurred most often in late adolescence, and declined each year thereafter (aged 18-22 years). Sexual victimization among university women was highest for those who had been first assaulted in early adolescence (4.6 times nonvictims). Detailed analyses revealed that the more severe the adolescent experience the greater the risk of collegiate revictimization. Adolescent victims of rape or attempted rape, in particular, were 4.4 times more likely to be as seriously assaulted during their 1st year of college. CONCLUSION: A linear path model is suggested. Childhood victimization increased the risk of adolescent victimization, which in turn significantly affected the likelihood of revictimization among college women.

Fluid mechanic constraints on spider ballooning.

Early investigations point to ballooning as an important mechanism for the dispersal of spiders. Most studies, however, have focused on collecting and interpreting observations with the aim of establishing the statistical characteristics of the dispersed population and their relation to biotic factors. With few exceptions, important physical factors that mechanically constrain the ballooning activity have been neglected or simply ignored. Especially important are various fluid mechanics phenomena that affect the initiation and maintenance of the ballooning activity. By reference to a simple mechanical model that simulates the essential drag characteristics of the ballooning spider-filament system, a region is defined, in terms of the relevant physical parameters, within which the ballooning activity can be initiated. Extension of the model allows a numerical investigation of the influence of vertical wind oscillations on the velocities and trajectories of ballooning spider-filament systems. Results are presented and discussed to illustrate the relative importance to ballooning of drag on the spider's body and on the silk filament to which it is attached.

The onset of drinking and intoxication among university students.

To study the effect of the onset of drinking on subsequent alcohol use, self-administered questionnaires were completed by 856 unmarried undergraduate students from two universities in the southeastern region of the United States. The present study focuses on the 524 (61.2%) students who reported using alcohol at least occasionally. In this subsample, the strongest predictors of the extent of undergraduate intoxication are the frequency of intoxication at the onset of drinking and age at the onset. The more often an individual drinks to intoxication and the younger that individual begins to drink, the more frequently he or she will become intoxicated when a university student. Racial differences in the extent of undergraduate intoxication were also found. White students were markedly more prone to intoxication than were Black students. Sex differences, although not statistically significant, showed a tendency for drunkenness among male undergraduates to exceed that among female undergraduates. The implications of the findings for intervention and prevention strategies are discussed.

Antecedents of collegiate drinking.

A model designed to explain variations in the use of alcohol among undergraduates draws together three categories of variables: (1) sociocultural-race, sex, and population of student's hometown; (2) familial characteristics-father's occupation, parents' marital status, and closeness to a problem drinker; and (3) the onset of student drinking-age at first drinking and extent of drinking at its onset. A 10% random sample was drawn from the undergraduate students enrolled in two state-supported universities in the southeastern U.S. The present analysis focuses on 856 nonmarried, full-time undergraduate students. Overall, the findings show that race, degree of closeness to a problem-drinker, age at the onset of drinking, and its extent markedly influence the level of alcohol consumption among undergraduates. The strongest overall predictor of undergraduate drinking is the extent of adolescent consumption.

Race, sex, marihuana use and alcohol intoxication in college students.

In college students, alcohol intoxication was more frequent in men than in women, in Whites than in Blacks and in White women than in Black women. The difference between White and Black men was negligible. Only gender differences were noted in marihuana use.

Homicide and suicide among the Cherokee and Lumbee Indians of North Carolina.

The Cherokee and Lumbee, the two major Indian populations in North Carolina, have exhibited similarities in patterns of homicide and suicide. Both Indian populations have higher rates of homicidal than of suicidal death. Yet in 1972-73, the Lumbee homicide rates was considerably higher than that for the Cherokee, but the Cherokee's suicide rate exceeded that for the Lumbee. During 1974-1976, the Cherokee manifested excessively high rates of violent death, with suicide increasing faster than homicide. The Lumbee homicide rate declined during this period, while the suicide rate increased. Lumbee violence patterns indicate a slight dissipation of cultural traits that predispose them to aggressive behaviour and the concomitant emergence of a trend toward self-destructive behaviour. The rise in Cherokee suicide rate may be consistent with the harmony Ethic of some tribe members, but the sharp increase in homicide may reflect the erosion of the traditional non-violent ethic among the band as a whole.

Regional variations in the characteristics of victims of violence.

This paper investigates variations in the characteristics of victims of violence in the four regions of North Carolina: the mountains, piedmont, coastal plains, and tidewater. Distinct patterns of homicide and suicide are found in each of these regions. The montains are characterized by high rates of suicide and low rates of homicide, while the coastal plains are marked by an opposite pattern, high homicide and low suicide. The two remaining regions of North Carolina, the piedmont and tidewater, have similar violence patterns. The piedmont has slightly higher rates of both homicide and suicide than the tidewater; however, both exhibit positive relationships between homicide and suicide rates. Socio-cultural dimensions of each of these regions are outlined. Those variables which differentiate areas having opposite violence patterns are isolated. Also, similarities between other regions manifesting comparable rates of homicide and suicide are cited. Within the socio-cultural context of each region, an examination of the variations in the characteristics of victims of violence is made. These characteristics include:. age, sex, marital status, race, occupation, time of injury, means of death type of premise of injury and, where applicable, type of weapon used.

Offender-victim relationships in criminal homicide followed by offender's suicide, North Carolina, 1972-1977.

An analysis of 90 cases of criminal homicide followed by suicide in North Carolina, 1972 to 1977. Homicidal victim-offender relationships were investigated in regard to age, sex, race and whether victim and offender were member of the same family, friends, acquaintances, or strangers. These results were compared with victim-offender relationships in 994 criminal homicide cases in North Carolina in which offenders did not commit suicide. Married white males over 30 years were much more involved in homicide-suicide than they were in homicide alone. In these homicide-suicide cases, the victim was usually the spouse. Except for marital status, characteristics of homicide offenders who killed themselves resembled those of suicide-only individuals much more than those of homicide-only offenders. In the homicide-suicide cases, the killing of someone in close relationship to the offender, often a wife, appeared to be part of the evolving process of suicide. This clearly has implications for intervention into marital strife and also for immediate treatment of homicide offenders who kill spouses and other family members.

Role interference: an analysis of suicide victims, homicide offenders, and non-violent individuals.

The relationship between role interference and suicidal, homicidal and non-violent behavior is investigated. Interference obtains to the extent that enactment of certain roles tends to impede the enactment of others. High degrees of interference in the performance of roles is generally frustrating to individuals and is a potential generator of outwardly directed violence. Low degrees of role interference is likewise disconcerting to persons but in the absence of an external target for aggression may lead to self deprecation and ultimately suicide. Detailed life histories of 98 suicide victims, 62 homicide offenders, and 76 non-violent individuals having no history of homicidal or suicidal behavior were studied. Homicide offenders suffered a higher incidence of role interference than the suicide or non-violent samples. Suicide victims tended to experience low degrees of such interference.

A study of the etiology of sociopathic behavior.

The purpose of this study is to attempt to indicate a possible process by which a sociopathic personality emerges. It is contended that sociopathic behavior can be understood in relation to the emergence of the self and the concomitant ability to take the role of the other. For the purposes of this study the sociopath is conceptualized as one who is deficient in role-taking ability, that is, he is unable to judge his own behavior from the viewpoint of another person. The socialization process is considered crucial in the emergence of the self and the ability to take the role of the other. Adequate socialization is that which take place under conditions of primary relations between the socializing agents and the person(s) being socialized. It is assumed therefore that socialization which occurs under conditions of secondary relations is inadequate. Socialization marked by secondary relations characteristically occurs within institutions. This study specifically focuses on the relationship between childhood institutionalization and sociopathic behavior in later life. The samples consisted of 50 sociopaths and 59 non-sociopaths (32 paranoid schizophrenics and 27 psychoneurotics) randomly drawn from the resident male caucasian population of the New Hampshire Hospital. Although age was not consciously controlled, each of the samples had similar age distributions with the majority of the patients falling between the ages of 20 and 34. The major hypothesis was: the incidence of early institutionalization (before the age of 16) among the sociopaths will be significantly higher than for mental patients diagnosed other than sociopathic. The data were classified as follows: institutionalization was divided into two types; orphanages and "other residential institutions" solely responsible for the care of the child. The findings indicate that there is a statistically significant association between early institutionalization and sociopathic behavior in later life. The incidence of institutionalization was consistently higher for the sociopaths than for the total non-sociopathic sample and for each sub-set of that sample. The findings of this study seem to support the theoretical assumption that childhood socialization that takes place under conditions of secondary relations between the child and the socializing agents will be ineffective for the development of a self with adequate role-taking ability. Sociopathic behavior may be a consequence of such socialization experiences.