bluuebunny/crossref_metadata_2025 huggingface dataset:
A pilot study of the development and implementation of a ‘best practice’ patient information booklet for patients with chronic venous insufficiency
Authors: Bobridge A , Sandison S , Paterson J , Puckridge P , Esplin M
Published: May 2011

Objective

Chronic venous insufficiency (CVI) is a chronic condition that has a significant impact on the individual. For the effective, long-term management of CVI, it is important that patients are educated on the patho-physiology of the condition and strategies that can minimize the related complications. Therefore, the aim of this study was to develop and pilot a ‘best practice’ information booklet for CVI and to assess the impact of this booklet on CVI-related knowledge and quality of life (QOL).

Method

A ‘best practice’ CVI booklet was developed based on the best available evidence from the literature. Participants with a formal diagnosis of CVI with a clinical, aetiological, anatomical and pathological elements (CEAP) classification of 3–6 were recruited from vascular outpatient clinics at a tertiary hospital. Each participant was given and explained the CVI booklet and asked to undertake the recommended activities at home over the next six-month period. Measurements were taken at baseline, one month and six months postbooklet implementation via the previously validated Health Education Impact and the CVI Questionnaires.

Results

Twenty-six participants, aged 38–90 years (mean 71.8 ± 12.9 years) initially participated in the study, with 20 participants remaining at the six-month time point (77% completion rate). At the end of one month, there had been a significant improvement in doing at least one activity to improve CVI ( P = 0.010), monitoring CVI ( P = 0.045), having effective ways to prevent CVI symptoms ( P = 0.045), knowing CVI triggers ( P = 0.005), ability to travel by car and bus ( P = 0.05), undertaking social activities ( P = 0.030) and feeling less embarrassed about the legs ( P = 0.025). At trial end (6 months), there was a significant improvement in doing at least one activity to improve CVI ( P = 0.003), knowing CVI triggers ( P = 0.016), having effective ways of preventing CVI symptoms ( P = 0.008), worrying about the CVI ( P = 0.030), feeling hopeless because of CVI problems ( P = 0.007), leg and ankle pain ( P = 0.038), ability to do domestic duties ( P = 0.017), feeling nervous and tense ( P = 0.026), and feeling less embarrassed about the legs ( P = 0.008). Although other domains improved in the study, none of these improvements were statistically significant.

Conclusion

Although a small pilot study, the outcomes demonstrate that the implementation of a ‘best practice’ CVI information booklet into a patients management routine can improve both CVI-related knowledge and QOL.
Results of endovenous ClosureFast treatment for varicose veins in an outpatient setting
Authors: Bisang U , Meier T O , Enzler M , Thalhammer C , Husmann M , Amann-Vesti B R
Published: May 2011

Objective

Endovenous methods are increasingly used to treat varicose veins. We evaluated the outcome of patients treated with the new radiofrequency ablation (RFA)-ClosureFast catheter in an outpatient setting.

Method

Retrospective analysis of postinterventional duplex ultrasound (DUS), complication rate and quality of life of patients treated for incompetent saphenous veins.

Results

Between 2007 and 2009, 155 patients had been treated with ClosureFast. DUS was available from 73 (47%) patients (102 great [GSV] and 16 small [SSV] saphenous veins). After a mean follow-up of 12.2 months (range 1–29 months), DUS showed six (5.9%) open GSV and an occlusion of all treated SSV. One pulmonary embolism had occurred. Mean patient's satisfaction was 8.7 (10 = very satisfied), pain after one week 2.0 (no pain = 0, maximal = 10) and absence of work was 0.9 day (range 0–14 days).

Conclusion

RFA for incompetent saphenous veins can safely be performed in an outpatient setting with a low complication rate, minimal pain and fast recovery.
Successful management of recalcitrant infection related to total hip replacement using pedicled rectus femoris or vastus lateralis muscle flaps
Authors: Choa R. , Gundle R. , Critchley P. , Giele H.
Published: May 2011

Deep prosthetic joint infection remains an uncommon but serious complication of total hip replacement. We reviewed 24 patients with recalcitrant hip wounds following infected total hip replacement treated with either pedicled rectus femoris or vastus lateralis muscle flaps between 1998 and 2009. The mean age of the patients was 67.4 years (42 to 86) with ten men and 14 women.

There had been a mean of four (1 to 8) previous attempts to close the wound. A total of 20 rectus femoris and five vastus lateralis flaps were used, with one of each type of flap failing and requiring further reconstruction. All patients had positive microbiology. At a mean follow-up of 47 months (9 to 128), 22 patients had a healed wound and two had a persistent sinus. The prosthesis had been retained in five patients. In the remainder it had been removed, and subsequently re-implanted in nine patients. Six patients continued to take antibiotics at final follow-up.

This series demonstrates the effectiveness of pedicled muscle flaps in healing these infected wounds. The high number of previous debridements suggests that these flaps could have been used earlier.
Primary Goals for Weight Loss Questionnaire (PGWLQ): Development and Psychometric Evaluation in Overweight and Obese Adults
Authors: Murphy Kylie , Brennan Leah , Walkley Jeff , Reece John , Little Emma
Published: May 2011

Cognitive behavioural models suggest that individuals abandon their weight loss efforts because they fail to achieve their weight loss goal, their perceived benefits of weight loss (primary goals), or both. There are currently no published tools available to adequately measure primary goals. The purpose of the current study was to explore the factor structure and to evaluate the psychometric properties of the Primary Goals for Weight Loss Questionnaire (PGWLQ). One hundred and twenty-seven overweight and obese adult females actively trying to lose weight completed the PGWLQ. A four-factor solution (Comfort & Mobility; Fitness; Health & Illness; Participation & Activity) provided the best fit for the physical items, and a five-factor solution (Body Image & Self-esteem; Clothing Options & Fashion; Work Productivity & Opportunity; Social Life & Desirability; Sexual Confidence) provided the best fit for the psychosocial items. All PGWLQ factors demonstrated good convergent and discriminant validity. The PGWLQ demonstrated excellent internal consistency and weak to moderate test–retest reliability. Results of the present study suggest that the PGWLQ may be a promising research and clinical tool and further refinement of the PGWLQ and investigation of its factor structure is warranted.
Creep Crack Growth Under Complex Loading
Authors: Ainsworth R. A. , Dean D. W. , Budden P. J.
Published: May 2011

Fitness-for-service assessments of components operating at high temperature often require estimates of creep crack growth in service. Although methods for calculating creep crack growth are given in R5 and other codes, these methods are limited in terms of their range of application and can be over-conservative. This paper extends the current methods in a number of areas. First, a general expression is derived for relaxation of a reference stress for combined primary and secondary loading and significant in-service crack growth. Second, the reference stress history is used to develop an estimate of the transient creep crack tip parameter, C(t) , for elastic-plastic-creep material behaviour for combined loading. This both extends current methods to more complex loading and reduces some known conservatism in these current methods. The general expression for C(t) then enables creep crack growth in service to be estimated using data collected from standard tests under mechanical loading. Finally, the paper presents some finite element calculations for defects in cylinders with welding residual stresses as validation for the new approaches.
Microanalysis of Recycled Coarse Aggregate and Properties of No-Fines Pervious Recycled Concrete
Authors: Li Jiusu , Liu Zhaohui
Published: May 2011

Three types of recycled coarse aggregate (RCA) produced from old cement beams with designed compressive strengths of 40, 60, and 80 MPa, respectively, were employed for measurement by X-ray diffraction (XRD), infrared absorption spectroscopy (IR), and scanning electron microscope (SEM). The XRD result indicated that the presence of Ca(OH)2 and anhydrates in the attached old cement mortar of the RCA may result in a new chemical reaction between the old cement mortar and the new cementitious binders when mixed to produce no-fines pervious recycled concrete (NPRC), which was contributable to the bonding condition. IR analysis was used to investigate the differences among the three types of RCA. The IR result indicated that RCA produced by crushing cement concrete with lower strength tended to absorb more water, which would probably weaken the strength and durability when utilized to manufacture NPRC. SEM was also employed to investigate the microstructure of RCA and the result demonstrated that RCA produced from low compressive strength cement concrete had a relatively loose old interfacial transition zone (ITZ), whereas RCA produced from high compressive strength cement concrete had a dense old ITZ. NPRC specimens were made with RCA, which was produced from old concrete beams with a designed compressive strength of 40 MPa. Factors influencing the compressive strength and flexural strength of NPRC were investigated and the results showed that a smaller size distribution of recycled aggregate, the appropriate thickness of freshly coated cement paste layer, and the water-cement ratio preferred to enhance both compressive strength and flexural strength. Moreover, the compressive and flexural strength of NPRC could achieve 26.37 and 3.37 MPa, respectively, by being blended with 4 % silica fume. The Cantabro test was extended to evaluate the abrasion and shock resistance of NPRC in this study. The Cantabro result suggested that RCA graded with a particle size distribution of 4.75–9.5 mm was favorable in terms of abrasion and shock resistance.
Retention Requirements for Alpine Ski Bindings
Authors: Ettlinger Carl F. , Dodge David , Johnson Robert J. , Shealy Jasper E. , Sargent Michael
Published: May 2011

Releasable ski bindings have helped to reduce the risk of lower leg injury but have not been effective in abating the risk of injury to the knee's anterior cruciate ligament (ACL). The authors theorized that if binding retention requirements were better understood, bindings could be developed that would eliminate excess retention under conditions associated with known mechanisms of injury, while providing an appropriate margin of retention during controlled skiing maneuvers. Currently, release/retention requirements for Alpine bindings are defined simply by a moment (couple). But the moment sensed by a skier's leg at release is dependent on not only the release moment to which the binding has been adjusted also but by where on the ski the load is applied. During the Winter of 2006–2007, the authors developed the instrumentation, protocols, and methods of data reduction and analysis necessary to express retention requirements of Alpine skiers in terms of load and load position on a virtual ski of infinite length. During the Winter of 2007–2008, 15 experienced skiers were fitted with a pair of skis in which one ski was equipped with a platform for measuring forces transverse to the long axis of the ski boot in a plane parallel to the bottom of the sole. Each subject in the study performed a series of skiing, recovery, and climbing maneuvers. Video and audio records of those maneuvers were synchronized with the 90 min of recorded data, allowing the data to be classified by skiing activity and reduced to a force and moment resolved about an axis approximating the skier's tibia. The force was then divided into the moment resulting in the position (lever arm) of the force necessary to produce the moment. Using current standards, the moment was scaled as a percentage of the recommended release moment. Loads applied to the inside edge of the rear body of the ski, an area commonly associated with ACL injuries, were rarely found to be both more than 45 cm from the tibia and more than 40 % of the recommended. The few events in this “zone of ACL vulnerability” were associated with loss of control while skiing backward at low speed. From these observations, a release simulating platform was developed, which isolated the binding from the ski. The platform sounded an alarm if the moment sensed by the simulator exceeded 50 % of the recommended release moment and the load was applied in the “zone of vulnerability.” In more than 120 min of skiing, the alarm never sounded, indicating that no inadvertent release would have taken place if the simulator had been an active release binding. However, subjects were able to initiate the alarm, thus simulating a release, by attempting to twist out of the binding with only the tail end of the ski engaged with the snow surface. The authors believe that the database and analytical techniques developed in this study may help to optimize the overall release/retention capabilities of future bindings.
Helmet Use and Self-Reported Risk Taking in Skiing and Snowboarding
Authors: Bianchi Giannina , Brügger Othmar , Niemann Steffen , Cavegn Mario
Published: May 2011

The aim of this study is to examine the correlation between helmet use and on-slope ski conduct. During the months of February and March 2009, eight trained interviewers asked 1550 skiers and snowboarders at 20 ski resorts in the German and French speaking parts of Switzerland a series of questions. The skiers and snowboarders were asked about their reasons for wearing or not wearing a helmet and about their behavior and conduct on the slopes. Three categories of people were identified: (1) Helmet wearers, (2) those who do not wear a helmet but intend to buy one, and (3) those who do not wear a helmet and have no intention of buying one. After assessing the outcome of the survey by performing a variance analysis, significant differences were found between the self-reported on-slope conduct of the helmet wearers and those who choose not to wear a helmet. No difference in self-rated ski conduct was found between the two categories of people not wearing a helmet. A stepwise multivariate logistic regression was used to compare the different control factors on self-reported risk behavior. To summarize, by becoming a helmet wearer, skiers and snowboarders tend to demonstrate a greater degree of willingness to take risks on the slopes. For this reason, the theory of risk compensation cannot be entirely ruled out. More importantly, however, independent variables such as age, gender, number of falls per day, or years of experience were found to make a far greater contribution toward helping us understand a person's willingness to take risks while skiing or snowboarding.
Evaluating the Performance of Helmet Linings Incorporating Fluid Channels
Authors: Stewart D. , Young L. R. , Goel R. , Christou G. , Gilchrist M. D.
Published: May 2011

Performance advantages of incorporating fluid channels into a foam made of DERTEX VN600 (vinyl nitrile) are evaluated. This foam has the potential to replace the traditional foam material of helmet liners, like expanded polystyrene (EPS). The experiments involved dropping a certified size E headform vertically onto a flat, solid anvil. Elastically deformable and resilient VN foam outperformed EPS during all impacts. Incorporating a viscous aqueous solution of 30 % by weight glycerin into 3/8 in. (0.95 cm) diameter channels machined through VN foam, reduced the peak headform acceleration by 12 % on first impact compared to VN foam samples without fluid channels. The reduction was 17 % when compared to EPS foam samples. The duration of the first impact increased by 27 % over EPS, significantly lowering the associated head injury criterion values. Repeated impact testing demonstrated an increasing performance advantage of incorporating fluid channels. Samples incorporating 30 % glycerin solution reduced the peak headform acceleration after six impacts by 50 % as compared to EPS.
Polarizing Filters in Ski Sports
Authors: Lingelbach Bernd , Jendrusch Gernot
Published: May 2011

Polarizing filters are suitable, e.g., for driving/motoring. They also have great advantages for sailing or angling. But are they useful in alpine skiing? A natural source for at least partly polarized light is not only the scattered light in the sky but also the reflected light on special materials. The reflected light on snow might be partly polarized, especially for compressed snow (traces in the snow) or ice patches. Depending on the direction of the polarization of a filter, the amount of information might be reduced in a skiing area because these polarized icy patches might become invisible.
Emergency Release for Winter Sports Equipment
Authors: Schott Wolfgang , Senner Veit
Published: May 2011

Using a pyrotechnical pill, Wintersports equipment can be electrically released and removed, where mechanical opening is impossible because of missing torque between binding and equipment, e.g., at avalanche and tree-well situations or at ski base jumping with a wingsuit. Since the pill driven binding opening is very fast (∼1 ms), it may also be advantageous at a ski downhill racer accident.
Analyzing the Riding Behavior of Recreational Skiers and Snowboarders
Authors: Schmitt Kai-Uwe , Niemetz Peter , Muser Markus
Published: May 2011

Video recordings of a ski slope were used in combination with a video-based tracking software to analyze the riding behavior of skiers and snowboarders. It was shown that the methodology is a powerful tool to measure biomechanical parameters such as the speed and curve radii of individual skiers and snowboarders. A total of 6821 observations was recorded and evaluated. Average riding speeds ranged from 16 to 32 km/h (on the different parts of the slope that were analyzed) with maximum speeds of up to 113 km/h. Average curve radii between 6.2 and 9.3 m were measured.
Reaction Times of Skiers and Snowboarders
Authors: Harley Erin M. , Scher Irving S. , Stepan Lenka , Young Douglas E. , Shealy Jasper
Published: May 2011

Collisions with obstacles, such as trees, rocks, and other people, are a common occurrence in the sports of skiing and snowboarding. Once an obstacle becomes visible, whether or not the skier has time to avoid it is largely determined by that skier's reaction time (RT)—the time it takes to detect and identify the obstacle, make a decision about how to respond, and initiate that response. Stopping and turning RTs were measured in ten expert skiers and four expert snowboarders at Mammoth Mountain, California. Participants were told to search for a sign along a closed intermediate course and to execute the instruction on the sign as quickly as possible. The sign was positioned such that it was not visible until participants crested a berm. Two high-speed video cameras captured the movements of each participant. RT was defined as the time between when the sign first came into view and when the skier or snowboarder initiated a response (the time of initial ski, snowboard, or body movement away from the original path or arc of the participant). The average RT for skiers and snowboarders was 856 and 1056 ms, respectively. No difference in RT was observed between stopping and turning responses. These data can be used to estimate the limits of performance for an attentive, experienced skier or snowboarder under good environmental conditions.
Gender-Specific Effects of Smoking and Alcohol Consumption on the Risk of Falling in Downhill Skiers
Authors: Burtscher M. , Pühringer R. , Werner I. , Ruedl G. , Sommersacher R. , Woldrich T. , Nachbauer W.
Published: May 2011

More than 90 % of all accidents on ski slopes are caused by falls without other skiers involved. Only little information is available about causes of falling. Recently, we identified several risk factors and triggers, including alcohol consumption and smoking, associated with an increased fall risk. The main goal of the present study was to focus on gender-specific effects of smoking and alcohol consumption on the risk of falling in downhill skiers. Randomized inquiries were performed on five occasions in five ski areas where 1607 downhill skiers, 928 males and 679 females, were interviewed by a standardized questionnaire. Data were collected on demographic characteristics, smoking habits, regular physical activity, skiing skills, preferred slopes, alcohol consumption, snow and weather conditions, and the number of preceding falls on the day of the inquiry. Conditional logistic-regression analysis was used to estimate adjusted odds ratios for fall outcome. Logistic-regression analysis revealed that the fall risk during skiing was increased only in males that are 30 years of age or older: 1.6-fold when they were non-smokers but drank alcohol and 2.2-fold when they were smokers and drank alcohol on the skiing day. In female skiers, this risk was increased in the age groups below 30 and those 30 years and older: 1.9- and 2.2-fold for smokers who did not drink alcohol, 2.2- and 2.8-fold when they were non-smokers but consumed alcohol, and 3.4- and 5.1-fold when they were smokers and drank alcohol on the skiing day. These findings demonstrate that being a smoker or drinking alcohol on the skiing day increases the risk of falling especially in female downhill skiers. The combination of both factors results in an additive risk increase. The avoidance of these risk factors could help to reduce the frequency of falls and probably also that of injuries particularly in female skiers.
Hydration Packs Modify Professional Skiers Hydration Levels in All Day Skiing: A Randomized Controlled Trial
Authors: Waddington Gordon Stuart , Dickson Tracey J. , Trathen Stephen Douglas , Adams Roger David
Published: May 2011

The effect of a backpack hydration system on hydration levels of professional snowsport employees was explored by an interdisciplinary research team. On two consecutive days, a total of 33 subjects was involved in a study where on one day they would wear a backpack hydration pack, while on the other day they would hydrate as per their normal work practice. When the two days were compared, wearing a hydration pack resulted in significantly higher levels of hydration, 0.4 % (95 % CI 0.017–0.765, range of −1.40–3.00 %) significant at a 0.05 two-tailed level, at the end of the day. It is not clear as to whether this level of hydration change is important in terms of impacting on the skills required for safe snowsports participation. However, if the effects are continuous, any negative hydration change may be associated with some level of performance loss. This research raises important questions related to access to water by all users of snowsport resorts. If hydration levels may be impacted upon by the use of hydration packs, there may be other aspects of the design “equation” that may facilitate optimal hydration levels for snowsport participants.
Are ACL Injuries Related to Perceived Fatigue in Female Skiers?
Authors: Ruedl G. , Schranz A. , Fink C. , Pocecco E. , Nachbauer W. , Burtscher M.
Published: May 2011

In alpine skiing, knee injuries show marked sex differences, as female recreational skiers have a twofold greater incidence of knee injuries and a threefold higher anterior cruciate ligament (ACL) injury risk than male skiers. General preventive recommendations to reduce the incidence of ski injuries include avoiding fatigue. However, no study has yet examined to which extent ACL injuries in female recreational skiers are related to perceived fatigue. Therefore, 68 ACL injured female skiers and 136 matched controls were interviewed about skiing time and perception of fatigue in legs and the whole body at the time point of accident and questioning, respectively. In addition, skiing ability, self estimated fitness level, quantity and quality of breaks per run, sleeping quality, and group skiing and skill level of group members have been recorded. Patients and controls differ significantly regarding the duration of skiing as about 81 % of ACL injuries occurred within the first 3 h (odds ratio=4.4; P<0.001). In patients about 71 % and in controls about 27 % felt no fatigue or a trace of fatigue in their legs at the time of injury and questioning, respectively (P<0.001). No other factors showed a significant difference. Therefore, fatigue seems no major risk factor for an ACL injury in female recreational skiing.
Aging Trends in Alpine Skiing
Authors: Shealy J. E. , Ettlinger C. F. , Johnson R. J.
Published: May 2011

As the skiing population in the United States ages, what are the concerns with regard to age-related injuries and possible injury prevention strategies? Between December 1972 and April 2006 the authors evaluated prospectively 18 692 injuries sustained by 17 197 skiers that were reported to the injury clinic which operated in the base lodge of a moderate size northern Vermont ski area. Data from a total of 3966 uninjured randomly selected controls were also collected. During that time approximately 6 830 200 skier-visits were accrued by the area. The overall injury rate averaged 365 mean days between injuries over the 34 years of the study and decreased by approximately 50 % over the period. The regressed mean age of the injured population during that time increased from 22.8 to 32.4 years-of-age. The control population increased from 22.9 to 35.8 years-of-age. The increase in the age of the skiing public roughly matches the age increases in the U.S. population. This analysis divides the 34 years of the study into two equal sized periods: An early and a later one. The population is then divided into two age cohorts (55 and under, and over 55 years of age) to see what trends can be identified that are age-related as opposed to time-related. The various injuries have been grouped into 13 major injury groups for the purpose of analysis. Seven of the 13 injury groups show a lower risk of injury for skiers over 55 than the general skiing public; ranging from 11 % to as much as 42 % lower. Five injury groups show no difference. The only increased major injury group found to be age-related is tibial plateau fractures, at 5.7 times higher than the general skiing population. Overall the over 55 age group is at a lower risk of injury than the general skiing public.
Skiing and Boarding Injuries on Norwegian Slopes during Two Winter Seasons
Authors: Ekeland Arne , Rødven Andreas
Published: May 2011

A central ski patrol-based registration of skiing and boarding injuries was performed by the Norwegian Ski Lift Association during the winter seasons of 2006/2007 and 2007/2008. A total of 8149 injured skiers/boarders and 6.024 million skier/boarder days were recorded during the two seasons, giving an injury rate of 1.35 injured per 1000 skier/boarder days. Most of the injuries occurred during alpine skiing (64 %) and snowboarding (31 %), compared to telemark skiing (2 %) and skiboarding (3 %). Wrist injuries were common among injured snowboarders (25 %) compared to 4–6 % for the others (P<0.001). The knee was the main injury location in alpine skiers (25 %) compared to 21 % among skiboarders, 19 % among telemarkers, and only 8 % among snowboarders (P<0.001). The percentage of knee injuries in females (30 %) was almost twice as high as for males (16 %) (P<0.001), whereas shoulder injuries was twice as high in males (16 %) as in females (7 %) (P<0.001). As percent of all injuries injured snowboarders suffered more fractures (30 %) than skiboarders (27 %), alpine (22 %), and telemark skiers (18 %) (P<0.001), but fracture of the lower leg was uncommon among snowboarders (0.5 %) and telemarkers (0.6 %) compared to alpine skiers (6 %) and skiboarders (9 %) (P<0.001). Lower leg fractures accounted for 5 % of the injured alpine skiers 20 years and older, 3 % for adolescents aged 13–19 years compared to 12 % for children 12 years and younger (P<0.001). Nineteen percent of the skiers/boarders were injured in terrain parks. They suffered more fractures and back injuries than those injured at other locations (P<0.001). Fifty-seven percent of injured skiers/boarders used helmet, and they had a lower prevalence of head injuries (15.9 %) than those without helmet (18.2 %) (P<0.01). In conclusion, injured alpine skiers were most prone to knee injuries, and skiboarders to lower leg fractures. This fracture was still a common injury for children in these two disciplines. Injured snowboarders were most prone to suffer wrist injuries. The prevalence of knee injuries among females was almost twice that of males, whereas the reverse was observed for shoulder injuries. Injured skiers/boarders wearing a helmet had a lower prevalence of head injuries than those without helmet.
Skiing and Snowboarding Injuries in the Czech Republic in Winter Seasons 2003–2008
Authors: Rokyta Jan , Chlad Rudolf
Published: May 2011

The goal of our observation was to evaluate the trends in the number and anatomic location of injuries sustained during downhill skiing, snowboarding, and cross-country skiing during the six seasons between 2003 and 2008 in the major skiing areas in the Czech Republic. There is a total of 33 skiing areas in the Czech Republic with a total ski slope length of 350 km and an hourly capacity of 300,000 people. The total number of injuries per season is around 5500, with the majority of the injured being men. An increase in the prevalence of upper extremity and snowboarding injuries was observed, as well as a decrease in the prevalence of head injuries and all sustained during cross-country and downhill skiing. A surprising discovery was that the overall injury rate was ∼1.0 injury/1000 skier or snowboarder days and 0.1 injury/1000 cross-country skier days.
Relative Motion of ACL Insertion Points In Vivo: A Case Study, Including Skiing Maneuvers
Authors: Freudiger Stefan , Vogt Wolfgang , Wirz Dieter
Published: May 2011

FASTRAK receivers were mounted on Kirschner-wires inserted in the distal femur and proximal tibia, respectively. Relative motions of the anterior cruciate ligament (ACL) insertion points were calculated for a hypothesised ACL while diagnostic and skiing load cases were applied to the knee. The highest strains, in descending order were: (i) Lachman test (13.5 %), (ii) 20 N•m internal rotation load (10.6 %) and (iii) latero-medial knee movement (6.4 %). The Lachman-procedure not only produces anterior tibial translation (5.5 mm) but as well internal rotation (10.0°). The medial knee movement produces valgus (2.3°) and external rotation (15.6°), but induces flexion (9.7°) as well, which therefore increases ACL load due to a non physiological instantaneous centre of rotation.
Jumper Kinematics on Terrain Park Jumps: Relationship between Takeoff Speed and Distance Traveled
Authors: Shealy Jasper , Scher Irving , Stepan Lenka , Harley Erin
Published: May 2011

The performance of individuals jumping tabletop features in terrain parks has not been widely studied. A field study was conducted to measure the takeoff speed and horizontal distance achieved by jumpers at two tabletop style jump features: A smaller jump at Snow Summit, CA and a larger jump at Mammoth Mountain, CA, USA. Analyses were also conducted to determine the effects of equipment type (skis versus snowboard) on jumper kinematics. Before each data collection session, the physical dimensions of the jump were measured and recorded. For consecutive jumpers, the speed parallel to the ramp was measured at the end of the takeoff by using a laser speed trap accurate to 0.11 m/s. The landing zone was marked at 3.0 m intervals with colored dye, beginning just past the flat deck portion of the jump. A high-definition video camera was used to record the landing of each jumper, and the landing point of the projected center of mass was determined by using photogrammetry, accurate to within 5 cm. The actual landing distances measured in the field were compared to predicted landing distances by using ordinary ballistic equations. A total of 280 jumps was observed on the two features: 105 on skis and 175 on snowboards. The correlation coefficients between the square of the takeoff speed and the landing distance for the smaller and larger jumps were 0.75 (R2=0.56) and 0.41 (R2=0.16), respectively. The measured landing distances differed significantly from those predicted by models using the ballistic equations of motion. The average landing distance beyond the knuckle was 2.4 m on the smaller jump and 2.1 m on the larger jump. For both features, skier and snowboarder jumpers did not differ in average landing distance.
Reaction Forces and Moments in Carved Turns
Authors: Oberegger Ulrich Filippi , Kaps Peter , Kerber Walter , Mössner Martin , Schindelwig Kurt , Nachbauer Werner
Published: May 2011

We computed reaction forces and moments acting on a skier during a carved turn. We performed an inverse and a forward dynamic analysis. For a run of an elite skier, marker positions on skier and skis were obtained as functions of time from a video analysis and smoothed by splines. Linear velocities and accelerations were computed by differentiating the splines, angular velocities, and accelerations via rotation matrices. The forces acting at the right ski were measured with two Kistler force plates. For the inverse dynamics, we used an adapted Hanavan model for a skier consisting of upper body, left and right thighs, shanks, and skis. Applied forces considered were weight and ski-snow friction. Drag was neglected. By prescribing a lateral weight distribution from the outer to the inner ski during the turn, reaction forces and moments at the left and right ankle, knee and hip joints were computed from the Newton-Euler equations of motion for constrained rigid multibody systems. The forward dynamics was performed with a three-segment model of a mono-skier consisting of trunk, thigh, and shank. Rotational joints were assumed in knee and hip. The track and the joint angles were prescribed. The inward lean angle was determined by a balance condition that led to nonholonomic constraints. After formulating the equations of motion in descriptor form, the resulting differential-algebraic system was solved with the numerical code RADAU5. Computed and measured reaction forces and moments agreed well within the accuracy of the measurements. The calculated joint loads are consistent with results from the literature. The forward dynamics model can be used to simulate consecutive ski turns. With parameter studies, the effects of slope, tracks, segment properties, ski-snow friction, and velocity of the skier on joint loads and performance of a run can be investigated. Further, injury mechanisms can be analyzed.
Mutations of calcium-sensing receptor gene: two novel mutations and overview of impact on calcium homeostasis
Authors: Livadariu Elena , Auriemma Renata S , Rydlewski Catherine , Vandeva Silvia , Hamoir Etienne , Burlacu Maria C , Maweja Sylvie , Thonnard Anne S , Betea Daniela , Vassart Gilbert , Daly Adrian F , Beckers Albert
Published: May 2011

Objective

Genetic disorders of calcium metabolism arise in a familial or sporadic setting. The calcium-sensing receptor (CASR) plays a key role in maintaining calcium homeostasis and study of theCASRgene can be clinically useful in determining etiology and appropriate therapeutic approaches. We report two cases of novelCASRgene mutations that illustrate the varying clinical presentations and discuss these in terms of the current understanding of CASR function.

Patients and methods

A 16-year-old patient had mild hypercalcemia associated with low-normal urinary calcium excretion and normal-to-high parathyroid hormone (PTH) levels. Because of negative family history, familial hypocalciuric hypercalcemia was originally excluded. The second patient was a 54-year-old man with symptomatic hypocalcemia, hyperphosphatemia, low PTH, and mild hypercalciuria. Familial investigation revealed the same phenotype in the patient's sister. The coding region of theCASRgene was sequenced in both probands and their available first-degree relatives.

Results

The first patient had a novel heterozygous inactivatingCASRmutation in exon 4, which predicted a p.A423K change; genetic analysis was negative in the parents. The second patient had a novel heterozygous activatingCASRmutation in exon 6, which predicted a p.E556K change; the affected sister of the proband was also positive.

Conclusions

We reported two novel heterozygous mutations of theCASRgene, an inactivating mutation in exon 4 and the first activating mutation reported to date in exon 6. These cases illustrate the importance of genetic testing ofCASRgene to aid correct diagnosis and to assist in clinical management.
Analysis of the efficacy and toxicity of sorafenib in thyroid cancer: a phase II study in a UK based population
Authors: Ahmed Merina , Barbachano Yolanda , Riddell Angela , Hickey Jen , Newbold Katie L , Viros Amaya , Harrington Kevin J , Marais Richard , Nutting Christopher M
Published: May 2011

Aim

To evaluate the tolerability and efficacy of sorafenib in patients with thyroid carcinoma.

Methods

Patients with progressive locally advanced/metastatic medullary thyroid carcinoma (MTC), or differentiated thyroid carcinoma (DTC) with non-radioiodine-avid disease, were treated with sorafenib 400 mg twice daily until disease progression. The primary endpoint was the radiological response rate (RR) at 6 months. Secondary endpoints were RR at 3, 9 and 12 months, biochemical responses, toxicity, biomarker analyses and progression free and overall survival (OS).

Results

A total of 34 patients were recruited to the study (15 medullary and 19 differentiated). After 6 months, the RR rate was 15% and a further 74% of patients achieved stable disease in the first 6 months. After 12 months of treatment, the RR was 21%. In the MTC patients, the RR at 12 months was 25% and OS was 100%. In DTC patients corresponding rates were 18 and 79% respectively. Median overall and progression-free survival points were not reached at 19 months. Commonest adverse events included hand–foot syndrome, other skin toxicities, diarrhoea and alopecia. Dose reduction was required in 79% patients. Median time on treatment was 16.5 months.

Conclusion

This study demonstrates that sorafenib is tolerable at reduced doses over prolonged periods of time in patients with thyroid cancer. Sorafenib leads to radiological and biochemical stabilisation of disease in the majority of these patients despite dose reductions.
A novel mutation in the calcium-sensing receptor in a French family with familial hypocalciuric hypercalcaemia
Authors: Al-Salameh Abdallah , Cetani Filomena , Pardi Elena , Vulpoi Carmen , Pierre Peggy , de Calan Loïc , Guyetant Serge , Jeunemaitre Xavier , Lecomte Pierre
Published: May 2011

Objective

The calcium-sensing receptor (CASR) has an important role in calcium homoeostasis by controlling PTH secretion and renal calcium handling. Inactivating mutations in the CASR gene (HGNC ID: 1514) cause familial hypocalciuric hypercalcaemia (FHH). We present a case of FHH patient to describe a novel mutation in the CASR.

Subjects and methods

A 34-year-old patient was referred because of recurrent hypercalcaemia after resection of two hyperplastic parathyroids. Extensive evaluation found elevated PTH and low calcium/creatinine clearance ratio. One of her three children had high serum calcium concentrations. Genetic studies were performed by PCR amplification of CASR coding exons and direct sequencing of PCR products. Transient transfection of the wild-type (WT) CASR and the mutant CASR into COS-7 was performed to assess functional impact of the mutation and the capacity of either protein to mediate increases in cellular levels of inositol phosphates (IPs).

Results

CASR sequencing found a previously undescribed heterozygous base substitution, determining a change of threonine to isoleucine at codon 550 (p.T550I) in the sixth exon. In contrast to those transfected with WT CASR, which showed a five- to eightfold increase in total IPs at high levels of calcium, COS-7 cells transfected with the (p.T550I) mutant showed no increase confirming to the inactivating nature of the mutation. COS-7 cells co-transfected with the WT and the (p.T550I) mutant showed an intermediate response suggesting a possible dominant negative effect.

Conclusion

This case report presents a not-yet-described mutation in the cysteine-rich region of the CASR extracellular domain, a mutation with a possible dominant negative effect.
Diabetes caused by insulin gene (INS) deletion: clinical characteristics of homozygous and heterozygous individuals
Authors: Raile Klemens , O'Connell Michele , Galler Angela , Werther George , Kühnen Peter , Krude Heiko , Blankenstein Oliver
Published: May 2011

Background

Mutations of the preproinsulin gene (INS) account for both permanent neonatal diabetes (PND) and adult-onset diabetes. The molecular mechanism of complete INS deletion has recently been published and we now add clinical data of homozygous and heterozygous subjects as well as the detailed mapping of the 646 bp deletion of the INS gene.

Methods

Location and size of the INS deletion was mapped in one case with PND and INS genotype of the whole family was further characterized by breakpoint-spanning PCR. The phenotype of monoallelic loss of INS was studied in 33 adult family members of a large consanguineous kindred with INS deletion.

Results

The 646 bp deletion was found in two individuals with PND that included exons 1 and 2 of the INS gene (chr11: g.2138434_2139080del646) and results in loss of approximately half of the preproinsulin protein. The two boys with homozygous INS deletion (D/D) presented with reduced birth weight, PND within the first 24 h of life and complete absence of C-peptide. Adult family members with the N/D had diabetes onset with earliest 25 years, while the oldest subject without diabetes was 45 years. INS-deletion-diabetes was initially treated with oral antidiabetic drugs but then transferred to insulin within 5–16 years. Overall, N/D-subjects (n=11) had a higher risk to develop insulin-dependent diabetes up to the fifth decade, if compared with normal subjects (n=22).

Conclusion

Complete loss of the human INS gene results in neonatal diabetes, while heterozygous INS deletion is a strong risk factor for developing insulin-dependent diabetes at adult age.
GATA transcription factors regulate LHβ gene expression
Authors: Lo Ann , Zheng Weiming , Gong Yimei , Crochet John R , Halvorson Lisa M
Published: May 2011

The GATA family of transcription factors are critical determinants of cell differentiation as well as regulation of adult gene expression throughout the reproductive axis. Within the anterior pituitary gland, GATA factors have been shown to increase glycoprotein α-subunit gene promoter activity; however, nothing has been known about the impact of these factors on expression of the gonadotropin β-subunits. In this study, we demonstrate expression of both GATA2 and GATA4 in primary mouse gonadotropes and the gonadotrope cell line, LβT2. Based on the transient transfection in fibroblast cells, GATA factors increase LH β-subunit gene (LHβ) promoter activity alone and in synergy with the orphan nuclear receptors steroidogenic factor-1 (SF-1) and liver receptor homologue-1 (LRH-1). The GATA response was localized to a DNA regulatory region at position −101 in the ratLHβgene promoter which overlaps with a previously described cis-element for pituitary homeobox-1 (Pitx1) and is flanked by two SF-1/LRH-1 regulatory sites. As determined by gel shift, GATA and Pitx1 can compete for binding to this element. Furthermore, mutation analysis revealed a requirement for both the GATA/Pitx1 and the SF-1/LRH-1 cis-elements in order to achieve synergy. These studies identify a novel role for GATA transcription factors in the pituitary and reveal additional molecular mechanisms by which precise modulation ofLHβgene expression can be achieved.
Upregulation of β-cell genes and improved function in rodent islets following chronic glucokinase activation
Authors: Gill D , Brocklehurst K J , Brown H W G , Smith D M
Published: May 2011

Glucokinase (GK) plays a critical role in controlling blood glucose; GK activators have been shown to stimulate insulin secretion acutely bothin vitroandin vivo. Sustained stimulation of insulin secretion could potentially lead to β-cell exhaustion; this study examines the effect of chronic GK activation on β-cells. Gene expression and insulin secretion were measured in rodent islets treatedin vitrowith GKA71 for 72 h. Key β-cell gene expression was measured in rat, mouse and global GK heterozygous knockout mouse islets (gkdel/wt). Insulin secretion, after chronic exposure to GKA71, was measured in perifused rat islets. GKA71 acutely increased insulin secretion in rat islets in a glucose-dependent manner. Chronic culture of mouse islets with GKA71 in 5 mmol/l glucose significantly increased the expression of insulin, IAPP, GLUT2, PDX1 and PC1 and decreased the expression of C/EBPβ compared with 5 mmol/l glucose alone. Similar increases were shown for insulin, GLUT2, IAPP and PC1 in chronically treated rat islets. Insulin mRNA was also increased in GKA71-treatedgkdel/wtislets. No changes inGKmRNA were observed. Glucose-stimulated insulin secretion was improved in perifused rat islets following chronic treatment with GKA71. This was associated with a greater insulin content and GK protein level. Chronic treatment of rodent islets with GKA71 showed an upregulation of key β-cell genes including insulin and an increase in insulin content and GK protein compared with glucose alone.
Effects of Different Abutment Connection Designs on the Stress Distribution Around Five Different Implants: A 3-Dimensional Finite Element Analysis
Authors: Balik Ali , Karatas Meltem Ozdemir , Keskin Haluk
Published: May 2011

The stability of the bone-implant interface is required for the long-term favorable clinical outcome of implant-supported prosthetic rehabilitation. The implant failures that occur after the functional loading are mainly related to biomechanical factors. Micro movements and vibrations due to occlusal forces can lead to mechanical complications such as loosening of the screw and fractures of the abutment or implants. The aim of this study was to investigate the strain distributions in the connection areas of different implant-abutment connection systems under similar loading conditions. Five different implant-abutment connection designs from 5 different manufacturers were evaluated in this study. The investigation was performed with software using the finite element method. The geometrical modeling of the implant systems was done with CATIA virtual design software. The MSC NASTRAN solver and PATRAN postprocessing program were used to perform the linear static solution. According to the analysis, the implant-abutment connection system with external hexagonal connection showed the highest strain values, and the internal hexagonal implant-abutment connection system showed the lowest strain values. Conical + internal hexagonal and screw-in implant abutment connection interface is more successful than other systems in cases with increased vertical dimension, particularly in the posterior region.
Planning for Immediate Loading of Implant-Supported Prostheses: Literature Review
Authors: Delben Juliana Aparecida , Goiato Marcelo Coelho , Pellizzer Eduardo Piza , Filho Osvaldo Magro
Published: May 2011

The aim of this study was to present the factors that influence planning for immediate loading of implants through a literature review for treatment success. Research was conducted in the PubMed database including the key words immediate implant loading, implant-supported prostheses, and implant planning for studies published from 2000 to 2011. Forty-eight articles were used in this review to describe the indications and counterindications, presurgical planning, and technologies available for planning of this treatment alternative.