bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Analysis of Crystalline and Double-Junction Amorphous Silicon Modules Performance in Outdoor Conditions
Authors: Cornaro Cristina , Musella Davide
Published: June 2013

The paper deals with an extensive photovoltaic (PV) modules monitoring activity carried out at the outdoor station ESTER (Solar Energy TEst and Research) of the University of Rome Tor Vergata, Italy. The purpose of the work was to evaluate and compare the performance of PV silicon modules of polycrystalline (poli-Si) and amorphous (a-Si) technologies during a medium-term outdoor exposure at optimized tilt angle, facing south. Two PV modules, one polycrystalline silicon and one double-junction amorphous silicon, have been exposed since May 2009 until Oct. 2010. A complete characterization of the weather conditions at the site during the test has been performed, and the most relevant parameters for the performance comparison of the two technologies have been derived. In order to compare different technologies and power productions, the energy yield (Y) and performance ratio (PR) for the two modules have been evaluated on a monthly and yearly basis. The typical seasonal trend of PR has been observed for the polycrystalline module, essentially due to the temperature influence on the module performance. For the a-Si module, instead, a degradation trend has been observed for the first months of operation. Subsequently, a significant recovery in the PR and energy production has been registered.
Prediction of Capillary Tube Adiabatic Flow Properties in the Absence of Precise Geometric Information
Authors: Abbasi Bahman
Published: June 2013

Capillary tubes have been used in household refrigerators and other cooling systems for several decades. Complicated geometry, inevitable manufacturing variations, and complex two-phase phenomena have been major prohibitory factors in the development of reliable and efficient modeling tools to analyze the flow properties inside capillary tubes. Friction factor correlations as are available in the open literature, and as examined by the author, unanimously fail to give an accurate analysis of the refrigerant flow. The delicate operation of a capillary tube makes experimentation cumbersome, time and cost intensive, and prone to errors. The present study introduces a method to utilize the data obtained from a standard nitrogen flow test for a given capillary tube to compensate for the geometric uncertainties and predict refrigerant flow properties through the tube at any desired spatial resolution, inlet state, and flow rate. Therefore, exploratory studies and capillary tube modifications for the purpose of system development and optimization can be greatly simplified.
Solution of Inverse Kinematics for 6R Robot Manipulators With Offset Wrist Based on Geometric Algebra
Authors: Fu Zhongtao , Yang Wenyu , Yang Zhen
Published: June 2013

In this paper, we present an efficient method based on geometric algebra for computing the solutions to the inverse kinematics problem (IKP) of the 6R robot manipulators with offset wrist. Due to the fact that there exist some difficulties to solve the inverse kinematics problem when the kinematics equations are complex, highly nonlinear, coupled and multiple solutions in terms of these robot manipulators stated mathematically, we apply the theory of Geometric Algebra to the kinematic modeling of 6R robot manipulators simply and generate closed-form kinematics equations, reformulate the problem as a generalized eigenvalue problem with symbolic elimination technique, and then yield 16 solutions. Finally, a spray painting robot, which conforms to the type of robot manipulators, is used as an example of implementation for the effectiveness and real-time of this method. The experimental results show that this method has a large advantage over the classical methods on geometric intuition, computation and real-time, and can be directly extended to all serial robot manipulators and completely automatized, which provides a new tool on the analysis and application of general robot manipulators.
A Vector Expression of the Constant-Orientation Singularity Locus of the Gough–Stewart Platform
Authors: Doyon Karine , Gosselin Clément , Cardou Philippe
Published: June 2013

This paper presents a vector expression of the constant-orientation singularity locus of the general Gough–Stewart platform. The third-degree vector expression obtained does not contain a constant term, which allows the factorization of an instance of the position vector, thereby leading to a very compact form. Additionally, an expression of the vector orthogonal to the singularity locus is obtained as a byproduct. An alternative expression that reduces the number of times that the position vector appears in the expression is also presented. It is shown that a simplified architecture such as that of the Minimal Simplified Symmetric Manipulator (MSSM) can significantly reduce the complexity of the coefficients appearing in the expression.
Residual Stress Characterization in a Dissimilar Metal Weld Nuclear Reactor Piping System Mock Up
Authors: Kerr Matthew , Prime Michael B. , Swenson Hunter , Buechler Miles A. , Steinzig Michael , Clausen Bjorn , Sisneros Thomas
Published: June 2013

Time-of-flight neutron diffraction, contour method, and surface hole drilling residual stress measurements were conducted at Los Alamos National Lab (LANL) on a lab sized plate specimen (P4) from phase 1 of the joint U.S. Nuclear Regulatory Commission and Electric Power Research Institute Weld Residual Stress (NRC/EPRI WRS) program. The specimen was fabricated from a 304L stainless steel plate containing a seven pass alloy 82 groove weld, restrained during welding and removed from the restraint for residual stress characterization. This paper presents neutron diffraction and contour method results, and compares these experimental stress measurements to a WRS finite element (FE) model. Finally, details are provided on the procedure used to calculate the residual stress distribution in the restrained or as welded condition in order to allow comparison to other residual stress data collected as part of phase 1 of the WRS program.
Thermomechanical Behavior of Pressure Tube Under Small Break Loss of Coolant Accident for PHWR
Authors: Yadav Ashwini K. , Kumar Ravi , Gupta Akhilesh , Chatterjee B. , Majumdar P. , Mukhopadhyay D.
Published: June 2013

Some postulated events for pressurized heavy water reactor (PHWR) small break loss of coolant accident (SBLOCA) may lead to flow stratification in the reactor channels. Such stratified flow causes a circumferential temperature gradient in the fuel bundle as well as in the surrounding pressure tube (PT). The present investigation has been performed to study the thermomechanical behavior of a PT under an asymmetric heat-up condition arising from flow stratification in a 19 pin fuel element simulator. A series of experiments has been carried out at various stratification levels and PT internal pressures. The asymmetrical heat-up creates a temperature difference of 400 °C across the diameter of the PT. At high temperature the internal pressure causes ballooning of the PT. With the stratification, ballooning is found to get initiated at top hot side of PT and further propagates unevenly over its periphery. Axially ballooning is found to get initiated from center and then propagates toward both the ends of the PT. This results in an axial temperature gradient on the PT in addition of circumferential gradient. For a pressure higher than 4.0 MPa, the integrity of PT is found to be lost due to the combined effect of circumferential and axial temperature gradient generated under uneven strain distribution.
Quality assurance and training procedures for computer‐aided detection and diagnosis systems in clinical usea)
Authors: Huo Zhimin , Summers Ronald M. , Paquerault Sophie , Lo Joseph , Hoffmeister Jeffrey , Armato Samuel G. , Freedman Matthew T. , Lin Jesse , Ben Lo Shih‐Chung , Petrick Nicholas , Sahiner Berkman , Fryd David , Yoshida Hiroyuki , Chan Heang‐Ping
Published: June 2013

Computer‐aided detection/diagnosis (CAD) is increasingly used for decision support by clinicians for detection and interpretation of diseases. However, there are no quality assurance (QA) requirements for CAD in clinical use at present. QA of CAD is important so that end users can be made aware of changes in CAD performance both due to intentional or unintentional causes. In addition, end‐user training is critical to prevent improper use of CAD, which could potentially result in lower overall clinical performance. Research on QA of CAD and user training are limited to date. The purpose of this paper is to bring attention to these issues, inform the readers of the opinions of the members of the American Association of Physicists in Medicine (AAPM) CAD subcommittee, and thus stimulate further discussion in the CAD community on these topics. The recommendations in this paper are intended to be work items for AAPM task groups that will be formed to address QA and user training issues on CAD in the future. The work items may serve as a framework for the discussion and eventual design of detailed QA and training procedures for physicists and users of CAD. Some of the recommendations are considered by the subcommittee to be reasonably easy and practical and can be implemented immediately by the end users; others are considered to be “best practice” approaches, which may require significant effort, additional tools, and proper training to implement. The eventual standardization of the requirements of QA procedures for CAD will have to be determined through consensus from members of the CAD community, and user training may require support of professional societies. It is expected that high‐quality CAD and proper use of CAD could allow these systems to achieve their true potential, thus benefiting both the patients and the clinicians, and may bring about more widespread clinical use of CAD for many other diseases and applications. It is hoped that the awareness of the need for appropriate CAD QA and user training will stimulate new ideas and approaches for implementing such procedures efficiently and effectively as well as funding opportunities to fulfill such critical efforts.
Gene Dosage-Dependent Negative Regulatory Role of β-Arrestin-2 in Polymicrobial Infection-Induced Inflammation
Authors: Sharma Deepika , Malik Ankit , Lee Eunhee , Britton Robert A. , Parameswaran Narayanan
Published: June 2013

β-arrestin-2 (β-arr2) is a scaffolding protein of the arrestin family with a wide variety of cellular functions. Recent studies have demonstrated differential roles for β-arr2 in inflammation following endotoxemia and cecal ligation and puncture (CLP) models of sepsis. Because CLP-induced inflammation involves response to fecal contents and necrotic cecum in addition to microbial challenge, in this study, we examined the role of β-arr2 in an exclusively polymicrobial infection (PMI) model. In addition, we examined the role of gene dosage of β-arr2 in polymicrobial sepsis. Our studies demonstrate that β-arr2 is a negative regulator of systemic inflammation in response to polymicrobial infection and that one allele is sufficient for this process. Our results further reveal that loss of β-arr2 leads to increased neutrophil sequestration and overt inflammation specifically in the lungs following polymicrobial infection. Consistent with this, specific NF-κB and mitogen-activated protein kinase (MAPK) signaling pathways were differentially activated in the β-arr2 knockout (KO) mice lungs compared to the wild type (WT) following PMI. Associated with enhanced inflammation in the KO mice, PMI-induced mortality was also significantly higher in KO mice than in WT mice. To understand the differential role of β-arr2 in different sepsis models, we used cell culture systems to evaluate inflammatory cytokine production following endotoxin and polymicrobial stimulation. Our results demonstrate cell-type- as well as stimulus-specific roles for β-arr2 in inflammation. Taken together, our results reveal a negative regulatory role for β-arr2 in polymicrobial infection-induced inflammation and further demonstrate that one allele of β-arr2 is sufficient to mediate most of these effects.
Hodgkin's lymphoma preceded by haemophagocytic lymphohistiocytosis
Authors: Morita Yoshinori , Kenzaka Tsuneaki , Yoshimoto Hideyuki , Ohno Nobuhito
Published: June 2013

A 71-year-old woman was admitted because of persistent fever for 2 weeks. A diagnosis of haemophagocytic lymphohistiocytosis (HLH) was made on the basis of persistent high fever, pancytopoenia, hyperferritinaemia, increased soluble interleukin-2 receptor (sIL-2R) levels and histiocytosis and hemophagocytosis in the bone marrow. CT showed neither infection nor lymphadenopathy. After administration of prednisolone, haematological findings improved and the fever resolved; however, the patient developed persistent fever after 6 months. In addition, levels of lactate dehydrogenase and sIL-2R increased again. CT scans revealed diffuse lymphadenopathy, and Hodgkin's lymphoma was diagnosed by lymph node biopsy. Progression of pancytopenia was observed, and bone marrow examination showed a relapse of HLH. After six courses of chemotherapy were given for Hodgkin's lymphoma, complete remission was achieved with no evidence of pancytopenia. Hodgkin's lymphoma may be the underlying cause in HLH cases of unknown aetiology. Hence, the clinical course should be carefully monitored even in the absence of lymphadenopathy.
CONSERVATIVE TREATMENT OF TOTAL PROXIMAL, NON-AVULSION, HAMSTRING MUSCLE - RUPTURE, IN HIGH LEVEL ATHLETES
Authors: Malliaropoulos Nikos , Psyllakis Panagiotis , Tsitas Kostas , Papalada Agapi
Published: June 2013

Background

Hamstring muscle injuries are notoriously found among the most common causes of abstinence and delayed return to sport, in a variety of track, field and other high level athletes. In this respect we present our experience of conservative treatment of total proximal, non-avulsed hamstring rupture in high-level track, field and other athletes and application of an integrated rehabilitation protocol.

Methods

Eleven high level athletes, nine men and two women, were diagnosed with sub/ total proximal, non-avulsed, hamstring rupture (grade III or IV strain). All of the patients were treated conservatively over a time scheme of twelve weeks.Then the athletes were ready to return to their complete sport–specific training.

Results

All the athletes were treated conservatively. All of them made a full return to their sport .Mean follow up time was from six months to two years. One male track athlete had a multiple reinjury history after his primary hamstring rupture (over 18 months of follow up).All the other athletes fully returned to their sports with no recurrent hamstring injuries during the follow up.

Conclusions

Indications that have been proposed for operative treatment of total proximal hamstring ruptures are most clear and widely acceptable when a bone avulsion is present off the ischial tuberosity.1However when it comes to total proximal, non avulsed ,hamstring rupture (grade III or IV strain) the operative indications may be relative and there still may be a place for integrated conservative treatment.2

Conservative treatment has to be based on the correct classification of the injury, the right clinical assessment at the acute phase as well as along the whole length of treatment.

Surgical treatment has an important role to play in complete proximal hamstring ruptures bearing in mind the right indications such as acute bone avulsions from the muscles’ origin.3
THYROID HORMONES RECEPTORS ARE PRESENT AND EFFECTIVE ON HEALTHY AND RUPTURED ROTATOR CUFF TENDONS. A PRELIMINARY REPORT
Authors: Oliva Francesco
Published: June 2013

Thyroid hormones (THs), T3 and T4, play an essential role in the development and metabolism of many tissues and organs, and have profound metabolic effects in adult life. Thyroid hormone receptors (TRs) seem to be ubiquitous, but, to our knowledge, their presence in tenocytes has not been investigated. We therefore evaluated the expression pattern of TRs isoforms in three groups of patients: one with rotator cuff tendons tears and with thyroid diseases, one with rotator cuff tendons tears without thyroid diseases, and one with healthy rotator cuff tendons and no thyroid disease. In addition, we evaluated the action of THs on growth and apoptosis of primary tenocyte cultures. The α/β nuclear receptor isoforms are present in healthy and pathologic rotator cuff tendons. THs enhance the growth and counteract apoptosis in primary tenocyte cultures in a dose and time dependent manner.
EFFECTS OF MAINTAINED INTENSE EXERCISE THROUGHOUT THE LIFE ON THE ADAPTIVE IMMUNE RESPONSE IN ELDERLY AND YOUNG ATHLETES
Authors: Moro-García Marco Antonio , Fernández-García Benjamin , Alonso-Arias Rebeca , Rodriguez-Alonso Manuel , Suárez García Francisco Manuel , López- Larrea Carlos
Published: June 2013

Background

Exercise induces a series of changes on the immune system depending on their intensity and duration.1 2In fact, transient states of immunosuppression are induced after intense physical activity3and yet beneficial exercise anti-inflammatory effects have been described over many diseases and longevity.1

Methods

To study the impact of intense exercise for long periods of life on adaptive immunity at different ages we compared phenotypical and functional features of T lymphocytes of young (n=27) and elderly athletes (n=15) with young (n=30) and elderly non-athletes (n=30). We characterized leukocyte and lymphocyte subpopulations by flow cytometry and measured the T cell proliferation and activation response (CD69) against anti-CD3. We also studied the percentage of recent thymic emigrants (RTEs) by quantification of TREC by real-time PCR. Specific antibody titers against CMV were determined by ELISA.

Results

Leucopenia was found in both groups of athletes, mainly explained by low levels of neutrophils and lymphocytes. Exercise induced higher frequencies of NK, B lymphocytes and CD8+ T cells, whereas CD4+ T lymphocytes showed significant lower levels in the elderly athletes. Moreover, young athletes showed significant differences in all parameters that define the immune risk profile (IRP), with characteristics of an aging immune system, but we did not find differences between elderly groups. Less differentiated subsets of T lymphocytes were more frequents in non-athletes, with the exception of CD8+ T lymphocytes in young individuals. The analysis of TREC content in the elderly groups showed no significant difference in either the CD4+ or CD8+ T lymphocytes. In the young non-athletes group we observe an increase in the content of TREC in CD8+ T cells, but not in CD4+ T cells. Moreover, functional response of CD4+ and CD8+ T lymphocytes was significantly impaired only in young but no in elderly athletes.

Conclusions

Intensive training for long periods throughout life induces important phenotypical and functional changes on the adaptive immune response. These changes are most striking in young individuals and they damped with physiologic immune aging.
DYNAMIC FOOT PRESSURE MEASUREMENTS IN ELITE TRACK AND FIELD ATHLETES
Authors: Malliaropoulos Nikolaos , Ritsioudi Magda , Finellis Vassilis , Padhiar Nat , Maffulli Nicola
Published: June 2013

Study design

Prospective Study.

Introduction

With the aim to deal with the probability of metatarsal bone stress injuries and stress fractures we detect and categorize functional alterations during forefoot loadings in plantar pressure area in athletes and explore the frequency of functional alterations.

Methods

58 elite track & field athletes (experimental group) and age/sex matched healthy volunteers (control group) conducted dynamic plantar foot pressure and leg-length measurements at the National Track and Field Center in Sports Medicine Clinic of S.E.G.A.S., Thessaloniki (Greece). Pressure, area and force during gait were measured. Measurements were performed during free walking at a speed of 5km/h. Measurements were conducted with T & T MEDILOGIC dynamic foot pressure platform with 2048 SSR-sensors. Statistical analysis and a comparison between the two groups for the metatarsal specific areas mean pressures in both foots (R: right foot, L: left foot) were made by using statistical analysis software. Clinical findings were also assessed.

Results

Anatomical alterations are descriptively presented. In functional alterations, four forefoot metatarsal print indices were categorized as follows: 1. metatarsal arch, 2. metatarsal fall, 3. metatarsal heads and 4. metatarsal varus.

Metatarsal fall and metatarsal varus mean loadings were higher in both feet for the non-athletes. Athletes presented higher percentage of metatarsal arch fall. Factor loadings indicate metatarsal arch fall as a separate factor compared with the other variables.

Conclusions

Present findings suggest that high impact sporting activities like sprinting, jumping, throwing and long distance running lead to variations in forefoot plantar pressure area. In 29 elite track and field athletes, metatarsal arch and metatarsal heads fall exist in a relatively high percentage. Control group did not have the same high percentage of metatarsal arch and metatarsal heads alteration as athletes but they had significantly higher loadings in metatarsal fall alteration.
EFFECTS OF RESISTANCE AND MULTICOMPONENT TRAINING ON BODY COMPOSITION AND PHYSICAL FITNESS OF INSTITUTIONALIZED ELDERLY WOMEN
Authors: Sousa Nelson , Mendes Romeu , Silva Sandro , Garrido Nuno , Abrantes Catarina , Reis Victor
Published: June 2013

Background

Physical fitness is an important indicator of health and quality of life in all population groups, and particularly in institutionalized elderly. In contrast, increased fat mass is associated with poor physical fitness and an increase in cardiovascular risk. The purpose of this study was to compare the effects of two short-term training programs on body composition and physical fitness in institutionalized elderly women.

Methods

Thirty-two women (aged 72.9±6.6 years) from three institutions of the north of Portugal, were randomly assigned into a resistance training group (n=12), a multicomponent training group (n=10), and a control group (n=10). Before and after training, body mass index, waist circumference, body fat mass, fat-free mass, and six independent physical fitness tests (back scratch, chair sit-and-reach, 30-s chair stand, arm curl, 8-foot up-and-go and 6-min walk) were assessed. Both training programs consisted of two weekly sessions during 12 weeks and were planned for moderate intensity (perceived exertion of 12–13 points on Borg scale, and a range on 50–69% of one repetition maximum). The resistance training protocol included leg press, leg extensions and curls, chest press, lateral pull-down, overhead press, arm curls and abdominal exercises. The multicomponent training protocol included aerobic exercise (walking and dancing), muscular endurance exercises (using elastic bands and free weights), balance and flexibility exercises. Two-way ANOVA with repeated measures was used to examine the effects of training programs.

Results

ANOVA indicated a significant main effect of group (p=0.000) for all physical fitness tests, with significant differences between both training groups and control. There were no differences between resistance training and multicomponent training. ANOVA also identified a significant main effect of time for 30-s chair (p=0.000), arm curl (p=0.002) and 6-min walk (p=0.000) in both training groups (baseline vs post-test). No significant changes were observed in body mass index, waist circumference, body fat mass and fat-free mass.

Conclusions

The data suggest that 12 weeks of multicomponent training were so effective in increasing physical fitness in institutionalized elderly, as resistance training. Further, multicomponent training demonstrated a wide practical applicability, and low cost development, unlike resistance training resources that need more expensive and complex logistics in such institutions. In contrast, 12 weeks of either resistance or multicomponent moderate training were not enough to induce changes in body composition.
MID-TERM RESULTS OF AUTOLOGOUS MATRIX INDUCED CHONDROGENESIS (AMIC) IN CARTILAGE KNEE SURGERY
Authors: Oheim Ralf , Behrens Peter , Volpi Piero , Girolamo Laura de , Reiss Eric Edgar , Zoch Werner , Anders Sven , Gille Justus
Published: June 2013

Introduction

The regeneration capacity of articular cartilage is very limited. Therefore, cartilage defects heal poorly and are known as prearthrotic lesions. Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment concept for localized full-thickness cartilage defects. This technique combines the well-established microfracturing with a collagen I/III scaffold fixated by fibrin glue.

Methods

Presented are medium-term results of two different prospective studies of patients treated with AMIC. Symptomatic full-thickness cartilage lesions (Outerbridge grade III or IV) were treated using AMIC (Chondro-Gide, Geistlich Pharma, Switzerland). Patients were initially evaluated by established knee scores (e.g. Lysholm score, IKDC score) and in selected cases by magnetic resonance imaging (MRI). Patients were re-evaluated up to 5 years after the initial procedure.

Results

In total 84 patients could be followed up. The average age of patients was in both groups 37 years (16–61 years). The mean defect size was 3.4 cm2respectively 4.2 cm2. The majority of patients were satisfied with the postoperative outcome, reporting a significant decrease of pain level. Significant improvement of the mean Lysholm score was observed as early as 1 year after AMIC and further increased values were noted up to two years postoperatively. MRI analysis showed moderate to complete filling with a normal to incidentally hyperintense signal in most cases.

Conclusion

AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. However, further studies with long-term follow-up are needed to determine whether the grafted area will maintain structural and functional integrity over time. Level of evidence: Prognostic study, Level IV.
EVALUATION OF PREMOTOR REACTION TIME, SENSATION OF POSITION AND JUMP PERFORMANCE ABILITY FOLLOWING RECONSTRUCTIVE ACL OPERATION
Authors: Hoseong Lee
Published: June 2013

Background

Although surgical reconstruction of the anterior cruciate ligament (ACL) is commonly performed to increase stability of the knee, persistent changes in neuromuscular function has frequently been cited as contributing to disability.1 2

Objective

This study investigated neuromuscular function (premotor reaction time, reproductive angle inaccuracy and jump ability) in a sample of patients 12 to 28 months following reconstructive ACL operation. In addition, the effect of leg dominance on neuromuscular function was analyzed in a sample of subjects without knee injury.

Methods

Ten healthy woman without knee injury and 10 patients following ACL operation participated in the study after they had been screened for neuromuscular function disorders. Premotor reaction time (PRT) of vastus medialis (VM), vastus lateralis (VL), hamstring medialis (HM), and hamstring lateralis (HL) were recorded by electromyography through the examination sudden knee eversion stress. Sensation of position were evaluated as a reproductive angle inaccuracy (RAI) in the difference between a specified angle (15°, 30°, 45°, 60°, and 75°) and the reproduction angle. Two physical therapists evaluated each subject's performance ability using a talent diagnose system (TDS Jump and TDS Flash Jump).

Results

The patients showed a significant increase in reaction time of hamstring operated legs (p<.05), systemic reaction time (TDS Flash Jump) (p<.05), and significant decrease in grounding time (TDS Jump) of operated legs (p<.05). For correlation coefficient, no statistically significant changes were found.

Conclusions

It was confirmed that a multi function of neuromuscular had decreased though one year or more passed after ACL reconstructive operation, therefore, should be provide information that recovers a multi function of neuromuscular in rehabilitation after ACL operation.
WHAT IS THE EVIDENCE OF TROCHLEOPLASTY IN TREATMENT OF PATELLOFEMORAL INSTABILITY? A SYSTEMATIC REVIEW AND COMPARISON WITH MPFL RECONSTRUCTION OUTCOMES
Authors: Testa Enrique Adrian , Amsler Felix , Camathias Carlo , Henle Philipp , Friederich Niklaus , Hirschmann Michael Tobias
Published: June 2013

Introduction

Trochleoplasty and reconstruction of the medial patellofemoral ligament (MPFL) are the most commonly used surgical treatment in patients with patellofemoral instability. Although there is an increasing number of publications dealing with treatment of patellofemoral instability, the clinical evidence about outcomes and in particular the question when to use which method is still scarce. It was our purpose to perform a systematic review on trochleoplasty in the treatment of patients with patellofemoral instability and compare the outcomes with those seen in patients treated by reconstruction of the MPFL.

Methods

Two independent orthopaedic surgeons performed a standardized search on Pubmed and other literature search engines and reviewed the obtained abstracts. All observational and experimental studies (case reports excluded) were then obtained in fulltext and again reviewed in a consensus meeting. 15 articles were included and analysed using the PEDro appraisal scoring system to assess its methodological quality. As comparison group the same process was done for MPFL reconstruction. 25 studies on MPFL reconstruction were obtained for comparison. The clinical and radiological outcomes of all papers was reviewed and compared. The studies investigated use a great variety of different outcome scoring instruments. Seven outcome variables were found consistently in most of the studies. Descriptive statistics was used for comparison of Kujala score, Lysholm score, patella tilt angle (PTA), sulcus angle (SA), apprehension test, redislocation and instability rates.

Results

There was no statistical significant difference in outcomes between both groups investigated. The MPFL reconstruction group showed a trend to better clinical outcomes. Mean postoperative Kujala score and Lysholm score increased significantly in both groups when compared to preoperatively (Kujala:61.4 to 80.8 and 46.9 to 88.8; Lysholm:55.5 to 78.5 and 59.9 to 91.1). Postoperatively a positive apprehension test was found in 8% of the MPFL group and in 20% of Trochleoplasty group. No difference in redislocation (2%) and instability (5–6%) rates between both groups. Mean PTA and SA showed a decrease in the trochleoplasty group (PTA: 30° to 15.9° and 12.6° to 8.1°, SA: 145.5° to 135.7° and 149° to 145.6°).

Conclusion

Considering all limitations this systematic review showed that trochleoplasty and MPFL reconstruction are able to deliver good clinical outcomes with stable patellofemoral joints. The minor differences in outcomes seem to be related to different patient populations and surgical techniques.
ACTIVE ANKLE RANGE OF MOTION ASSESSMENT IN ELITE TRACK AND FIELD ATHLETES: NORMATIVE VALUES
Authors: Malliaropoulos Nikolaos , Mertyri Dimitra , Tsitas Konstantinos , Papalada Agapi , Maffuli Nicola
Published: June 2013

Lateral ankle sprains account for 15% to 45% of all sports related injuries. Although often considered minor, they can lead to persistent disability in athletes and long term complications. Over the last decade, several studies have provided the opportunity to develop novel therapeutic strategies. Range of Motion is an important physical characteristic in athletes in terms of performance and injury prevention. Goniometry is an easy and cheap method to assess active ankle range of motion (AROM) to establish normative values. We assessed AROM in elite track and field athletes.

During 1999–2011, we measured bilaterally the Ankle AROM with the knee extended during an in-season period with a plastic double-arm goniometer in 137 Elite Greek Track and Field Athletes.

Male runners (dominant leg=70.90, non dominant leg=70.60) and jumpers(dominant leg=70.90, non dominant=70.90) had a higher mean AROM than throwers(dominant leg=69.20, non dominant=68.60).Female jumpers had a higher mean AROM(dominant leg=73.20, non dominant=72.30 than both runners(dominant leg=69.60, non dominant=69.50) and throwers (dominant leg=69.1, non dominant=69.50)
THE EFFECT OF EARLY SYSTEMATIC GYMNASTICS TRAINING ON POSTURAL CONTROL
Authors: Hernández Suárez María , Guimeraes Ribeiro Daniel , Hernández Rodriguez José Enerique , Rodríguez Ruíz David , García Manso Juan Manuel
Published: June 2013

Background

It's well established that by the age of 13, children are capable of applying a postural strategy looking very similar to that adopted by the adults. It's also widely acknowledgment that several years of sport training and competition implies to master stability, particularly in those sports requiring fine postural control, such as rhythmic gymnastics (Viullerme,et al, 2001). The aim of this study was to analyze the effect of early systematic gymnastic training on postural performance and control, by comparing young rhythmic gymnastics with their normally active counterparts (non-athletes).

Methods

Twenty-two gymnastics girls of national level (RG: 9.59±1.1 years old; 29.9±5.5kg; 1.37±0.08 m) and nineteen non-athletes girls (non-AT: 9.74±1.0 years old; 38.7±7.3kg; 1.40±0.07 m) participated in the investigation. All Subjects performed a battery of static balance tests under three different conditions: bipedal posture as immobile as possible for 20 seconds with Eyes Open (EO), Eyes Closed (EC) and Unipedal “en-dehors” Posture (UEP). All test were performed while standing on a platform force (MuscleLab® TM system, type PFMA 4000, collection rate of 100Hz). Based on the displacement of the center of pressure variables analyzed were: Ellipse Area of 95 (A95), Mean Velocity (MV). Data were tested (SPSS-v19) for normal distribution using the Shapiro-Wilk test and the U of Mann-Whitney adjustment for non-parametric data (significance level p≤0.05).

Results

Both investigated groups were similar as regards their anthropometric data. Neither the body mass (p=0.18) nor the body height (p=0.39) differentiated between the RG and non-AT. Moreover, significant differences were observed when comparing groups for MV, but not for A95, in all conditions. Interestingly, RG showed greater values of MV than non-AT in all conditions, although both groups had comparable values of surface A95. In absence of vision (EO vs EC), both groups significantly increased theirs MV, but there was a trend to be weaker this effect in gymnasts.

Conclusions

Expertise in RG did not seem to improve postural strategies compared with non-AT young females. This result is in accordance with other authors that supported the idea that improvement of performance due to learning is specific to the task and not directly transferred or generalized to more usual upright stance in young females. The level of a given athlete in his activity does not implicate a corresponding level in performing usual postures (Asseman, et al., 2004).
WHIPLASH INJURIES IN SPORTS ACTIVITIES. CLINICAL OUTCOME AND BIOMECHANICS
Authors: Tsoumpos Pantelis , Kafchitsas Kostas , Wilke Hans-Joachim , Evaνgelou Kostas , Kallivokas Alkis , Habermann Bjoern , Tsepis Elias , Bilis Evdokia , Matzaroglou Charalampos
Published: June 2013

Background

Cervical whiplash syndrome, or hyperextension-hyperflexion injury, is a common traumatic injury in sports activities. The mechanisms of injury that cause cervical whiplash syndrome vary, but they may be sufficient enough to cause chronic whiplash syndrome.

Methods and Patients

Over 150 injuries were recorded in sports in our Orthopaedic Departments between the years of 2008 and 2011. Whiplash spine injuries have been reported in most contact sports, including indoor soccer, basketball, and wrestling, and in several non contact sports, such as diving. Whiplash spine injuries are estimated to occur in high percentage of indoor soccer players, and most commonly on defensive players. Injury usually is secondary to high-velocity collisions between players, causing acceleration or deceleration of the head on the neck. Acceleration usually causes a whiplash type of extension force on the neck, while deceleration usually results in flexion forces.

Results

Serious injuries with neurologic sequelae remain infrequent in our series, and most of these injuries are self-limited. Quality of life assessment with Euro Quol and Sleep quality tools, in our series, suggest that there is no practical difference with healthy control group normalized regarding to sex, age, socioeconomic status and marital status after six months from initial trauma.

Discussion/Conclusions

Our study shows that there is a significant risk of whiplash type injuries in sports, especially indoor soccer. But serious injuries with neurologic sequelae and Chronic Whiplash Associated Disorders (WAD) remain very infrequent.
CHANGES IN RESPONSE OF VASTUS LATERALIS AND BICEPS FEMORIS AFTER A PHYSICAL ACTIVITY PROGRAM IN SUBJECTS DIAGNOSED WITH ALZHEIMER'S DISEASE
Authors: Rodríguez-Ruiz David , Sarmiento Sarmiento , Rodríguez-Matoso Darío , Henríquez del Pino Yessenia , Álvarez-Piñera Lorena , García-Manso Juan Manuel
Published: June 2013

Objetive

The aim of this study was to evaluate the effects of a physical activity (PA) program and subsequent detraining on the contractile capacity of the Vastus Lateralis (VL) and Biceps Femoris (BF) in patients diagnosed with Alzheimer's Disease (AD).

Methods

A total of 37 subjects were divided in: the intervention group (IG) consisted of 19 subjects (75.58 years ±6.18) and the control group (CG) for 18 subjects (79.92 years ±7.03). The PA intervention program was 4 month length, 60 training sessions and 5 days/week. The Tensiomyography (TMG) was used to assess the maximum radial displacement of the muscle belly (Dm) and the normalized response velocity (Vrn) in VL and BF of both legs. The assessment was performed before intervention (Pre), at the end of four months of intervention (Post) and two months after finishing the intervention (Post 2).

Results

Vrn for VL in IG increased in both legs after the intervention program (p≤0.05) while later decreased in the post2 (p≤0.05). Although we observe an increase of Vrn in CG (p≤0.05) it was not significantly higher than baseline levels (pre). The BF shows the same trend than VL for Vrn in IG, whereas in CG there is a tendency to maintain values. Dm for VL shows a decrease in post and an increased in post 2 assessment in IG. Dm values for left BF show significant differences in IG whereas in CG there is a tendency to maintain values. Dm for VL in IG decrease in both legs in post assessment (p≤0.05), and increases in post2 (p≤0.05). However, Dm showed only significant increases in right VL post assessment compared to baseline.

Conclusions

A PA program adapted to elderly diagnosed with AD, produces changes in morphology and muscle responses. Further, it enhances balance and motor skills, which results in a reduction in the risk of falls, improves the quality of life, and return to baseline values.
EXPERTISE AND STRATEGIES ON POSTURAL CONTROL OF YOUNG SURFERS AT DIFFERENT LEVEL OF COMPETITION
Authors: Guimaraes Ribeiro Daniel , Rodríguez Ruiz David , Hernández Suárez Maria , Rodríguez Matoso Dario , García Manso Juan Manuel
Published: June 2013

Background

Investigation of postural control in sports which require excellent postural performance, like surfing, gives insight into development of specific control strategies. The aim of the current study was to compare postural performance and strategy between young surfers of different levels of competition (international and national).

Methods

Twenty surfers were separated in two groups in accordance with their competition level: Ten international level surfers (INT) (17.7±1.7 years; 172.6±8.42 cm; 65.0±10.3 kg; 7.75±3.6 surfing years) and 10 national level surfers (NAT) (15.80±1.75 years; 168.60±12.02 cm; 59.25±12.12 kg; 6.6±3.6 surfing years). Subjects performed a battery of static balance tests under three different conditions: eyes open (EO), eyes closed (EC) and while performing a concurrent cognitive task (modified stroop test -MST). All tests were performed while standing on a platform force (MuscleLab® TM system, type PFMA 4000, collection rate of 100Hz), in bipedal posture, staying as immobile as possible for 30 seconds. Based on the displacement of the center of pressure, variables analyzed were: Ellipse Area of 95% (A95), Mean Velocity (MV) and frequency analysis (fast Fourier transform). Data was tested (SPSS-v17) for normal distribution using the Shapiro-Wilk test and the U of Mann-Whitney adjustment for non-parametric data (significance level p≤0.05).

Results

Both groups showed significantly greater values for MV when comparing the effect of the condition to the control test, EO vs. EC (p=0.007), and EO vs. MST (p=0.027). However, no differences were found in either of the variables when level of competition was analyzed. Although, INT showed smaller values of MV and A95 in all tests, except for A95 in the MST condition, evidencing better postural control (Palliardet al., 2006). Mean Velocity values for INT were: 17.1±3.9; 19.6±3.9; 19.5±7.2 mm/s2, and for NAT were: 18.7±3.3; 21.6±4.4; 21.2±7.2 mm/s2, for EO, EC, and MST condition, respectively. Values of A95 for INT were: 137.9 ±100.9; 148.1±58.7; 158.2 ±117.9 mm2and for NAT were: 141.9±44.9; 260.2±209.20; 138.6±55.9 mm2, again for EO,EC and MST. In respect to the spectral analysis, INT showed a trend to use a greater portion of energy in the low frequency band in all conditions.

Conclusions

Our results could indicate that experience in the surfing environment may result in specific strategy adaptation, by means of a more efficient visio-vestibular input (Chapmanet al., 2008). A better understanding of these strategies can help athletic trainers and clinicians to develop exercises in an attempt to enhance performance, reduce risk of musculoskeletal injuries or for rehabilitation therapies purposes.
TRUNK AND GLUTEUS-MEDIUS MUSCLES' FATIGABILITY DURING OCCUPATIONAL STANDING IN CLINICAL INSTRUCTORS WITH LOW BACK PAIN
Authors: Embaby Eman , Abdallah Amira
Published: June 2013

Background

Occupational standing is associated with low back pain (LBP) development. Yet, trunk and gluteus-medius muscles' fatigability has not been extensively studied during occupational standing. This study examined and correlated the rectus abdominus (RA), erector-spinae (ES), external oblique (EO), and gluteus-medius (GM) muscles' fatigability on both sides while standing in a confined area for 30 min.

Methods

Median frequency EMG data were collected from 15 female clinical instructors with chronic LBP (group A) and 15 asymptomatic controls (group B) (mean age 29.53±2.4 vs 29.07±2.4 years, weight 63.6±7 vs 60±7.8kg, and height 162.73±4 vs 162.8±6 cm respectively) using a spectrum analysis program. Data were collected in the first and last 5 min of the standing task.

Results

Using Mixed three-way ANOVA, groupA showed significantly (p<0.05) lower frequencies for the right and left ES, and right GM in the last 5min and significantly higher frequencies for the left RA in the first and last 5min than group B. In addition, the left ES and right EO, ES and GM in group B showed significantly higher frequencies and the left ES in groupA showed significantly lower frequencies in the last 5 min compared with the first. Moreover, the right RA showed significantly higher frequencies than the left in the last 5 min in groupB. Finally, there were significant (p<0.05) correlations among the median frequencies of the tested four muscles on the same side and between both sides in both groups.

Discussion/Conclusions

Clinical instructors with LBP are more liable to have higher trunk and gluteus-medius muscle fatigue than asymptomatic individuals. Thus, endurance training for these muscles should be included in the rehabilitation of such patients.Key words: Fatigability, Trunk, Gluteus-medius, EMG, Standing, LBP
OSGOOD SCHLATTER'S SYNDROME AND FUNCTIONAL IMPAIRMENT OF THE KNEE IN YOUNG FOOTBALL PLAYERS
Authors: Domingues Marcio
Published: June 2013

Football, like any contact sport it is susceptible to various kinds of injuries. Long-term planning is a characteristic and requirement of modern training as it can greatly increase training efficiency for future competitions (Bompa, 1999). Epidemiological findings suggest that little is known about the injury risk among the youngest players between six and twelve years and also the injury risk is low (Froholdt, Olsen and Bahr, 2009). This article focus on the understanding of microtraumatology in youth sports and examines one specific injury Osgood Schlatter disease, and the main mechanisms whereby such injury occur. It is referred the link between methodology of training and the prevention of overuse injuries in youth as it relates to maladaptive sport programs. There is an increasing awareness to growth related conditions and the relation of musculoskeletal development and the onset of youth related conditions. The aethology is complex and the risk factors underpinning injury occurrence are considered, along with injury avoidance tactics. Functional treatment is justified even if there is an increased formation of ossicles on non-immobilization of the joint, since such ossification occurs with only 20–25% of all cases of Osgood-Schlatter disease and the duration of the complaints is markedly less enhanced than with immobilization measures (Engel & Windhager, 1987). Treatment and recovery should attend to athletes specific conditions and involves activity modification and pain relief.