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1.
Cartilage ; 12(2): 162-168, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-30674199

RESUMO

OBJECTIVE: The purpose of this study was to retrospectively assess the frequency and characteristics of acetabular cartilage delamination (CD) in femoroacetabular impingement (FAI) patients and to assess the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of magnetic resonance arthrography (MRA) in detecting CD based on the radiologist report. DESIGN: This is a single-center retrospective review of consecutive patients operated for symptomatic FAI. All of the patients had a 1.5-T MR-arthrogram within 12 months preoperatively. MRA reports of these patients were compared with operation notes and surgical videos of all patients by two trained assessors. RESULTS: At surgery, CD of the acetabulum was present in 169 patients out of a total of 229 patients (74%). Only 6.5% (11 patients) of CD was described on the MRA reports preoperatively. The mean age of the patients was 37.6 ± 13.3 years. The average extent of delamination was 3.12 ± 1.5 cm2 with a mean coronal × sagittal extent of 0.68 × 4.33 cm. There was a significant difference regarding age (P = 0.002), alpha angle from frog view (P = 0.002), and alpha angle from anteroposterior view (P = 0.012) between the patients with delamination and without delamination. The majority of labral tears and cartilage damage were located in the anterosuperior quadrant. MRA sensitivity was 6%, specificity 98%, NPV 27%, and PPV 91% based on the radiologist report. CONCLUSION: The CD in patients with FAI can be severely underdiagnosed with MRA. There is a need for better standard diagnostic criteria to detect CD in patients with FAI.


Assuntos
Acetábulo/diagnóstico por imagem , Artrografia/estatística & dados numéricos , Doenças das Cartilagens/diagnóstico por imagem , Impacto Femoroacetabular/diagnóstico por imagem , Imageamento por Ressonância Magnética/estatística & dados numéricos , Acetábulo/lesões , Adulto , Artrografia/métodos , Doenças das Cartilagens/complicações , Cartilagem Articular/diagnóstico por imagem , Cartilagem Articular/lesões , Feminino , Impacto Femoroacetabular/complicações , Seguimentos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
2.
J Neuromuscul Dis ; 7(3): 247-256, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32417790

RESUMO

BACKGROUND: Promising genetic treatments targeting the molecular defect of severe early-onset genetic conditions are expected to dramatically improve patients' quality of life and disease epidemiology. Spinal Muscular Atrophy (SMA), is one of these conditions and approved therapeutic approaches have recently become available to patients. OBJECTIVE: Analysis of genetic and clinical data from SMA patients referred to the single public-sector provider of genetic services for the disease throughout Greece followed by a retrospective assessment in the context of epidemiology and genotype-phenotype associations. METHODS: Molecular genetic analysis and retrospective evaluation of findings for 361 patients tested positive for SMA- and 862 apparently healthy subjects from the general population. Spearman rank test and generalized linear models were applied to evaluate secondary modifying factors with respect to their impact on clinical severity and age of onset. RESULTS: Causative variations- including 5 novel variants- were detected indicating a minimal incidence of about 1/12,000, and a prevalence of at least 1.5/100,000. For prognosis a minimal model pertaining disease onset before 18 months was proposed to include copy numbers of NAIP (OR = 9.9;95% CI, 4.7 to 21) and SMN2 (OR = 6.2;95% CI, 2.5-15.2) genes as well as gender (OR = 2.2;95% CI, 1.04 to 4.6). CONCLUSIONS: This long-term survey shares valuable information on the current status and practices for SMA diagnosis on a population basis and provides an important reference point for the future assessment of strategic advances towards disease prevention and health care planning.


Assuntos
Atrofia Muscular Espinal/epidemiologia , Atrofia Muscular Espinal/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Associação Genética , Grécia , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Adulto Jovem
3.
Arch Orthop Trauma Surg ; 140(9): 1181-1189, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31989246

RESUMO

INTRODUCTION: Acromion fractures are rare and difficult to treat. There is no consensus on type of fixation. Due to the rarity of the injury, it is difficult to compare different techniques of osteosynthesis. OBJECTIVES: The aim of this study was to present the long-term results of an alternative method of plating Ogawa type IIB meta-acromion fractures and to review the literature. DESIGN: Retrospective study. MATERIALS AND METHODS: We present a case series of 11 consecutive patients with displaced Ogawa type IIB meta-acromion fracture, treated with open reduction internal fixation using a 3.5-mm contoured pelvic reconstruction plate with a 90° twist. Patients' mean age was 53.3 years (23-80 years) and the mean follow-up was 48.3 months (15 months-9 years). The outcomes related to pain and shoulder function were evaluated by Modified American Shoulder and Elbow Surgeons Score (ASES) and SF-36 score. All patients were asked about their satisfaction level. RESULTS: Nine out of eleven patients were included in this study. Eight of them obtained union and all were satisfied with the final outcome. The mean ASES and SF-36 score were 69.75 (42.4-98.14) and 61.37 (41.64-94.99), respectively, with poor scores to be largely associated with comorbidities and concomitant injuries. CONCLUSIONS: The use of 3.5-mm reconstruction plate with a 90° twist for open reduction internal fixation (ORIF) of meta-acromion fractures presents satisfactory results and could be technically a more stable biomechanical construct in comparison to the existing surgical techniques.


Assuntos
Acrômio , Placas Ósseas , Fixação Interna de Fraturas , Fraturas Ósseas/cirurgia , Acrômio/lesões , Acrômio/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
Orthop J Sports Med ; 6(11): 2325967118807906, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30480021

RESUMO

BACKGROUND: Anatomic glenoid reconstruction involves the use of distal tibial allograft for bony augmentation of the glenoid surface. An all-arthroscopic approach was recently described to avoid damage to the subscapularis tendon and preserve the capsule and labrum. PURPOSE: To explore and compare change in surgical time between 2 proposed methods used for the treatment of anterior shoulder instability-arthroscopic anatomic glenoid reconstruction (AAGR) and arthroscopic Latarjet (AL)-over successive procedures. We also compared graft positioning on the anterior glenoid surface between the 2 methods. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: This was a single-surgeon retrospective review of 54 cases of surgically treated recurrent anterior shoulder instability: 27 had AAGR with distal tibial allograft, while the other 27 had AL. AAGR with the distal tibial allograft was the primary choice for the treatment of anterior shoulder instability; however, AL was performed when tibial allograft was not available from the bone bank. Thus, there was an overlapping period for those 2 procedures. Procedure start and end times were recorded, and duration was calculated. Postoperative 3-dimensional computed tomography scans were reviewed, and graft position was judged to be in the lower third (desired position), middle third, or upper third of the anterior glenoid surface. To assess learning, these data were organized in chronological order of surgery, and each surgical cohort was divided into 3 chronological clusters of 9 patients each. Learning was assessed through change in operative time over successive clusters, change in variability of operative time among clusters, and change in graft positioning among clusters. Statistical analysis comprised a 2-tailed independent-sample t test and the Levene test for equality of variance. RESULTS: Our study found that AAGR was significantly faster to perform than AL in the early (P = .001), middle (P = .001), and late (P = .05) clusters of each cohort. Duration of surgery did not significantly improve across clusters within each cohort (P = .15-.79). There were no significant changes in the variability of surgical time in the AAGR group (P = .09) or the AL group (P = .13). Desired positioning of the bone graft on the anterior glenoid surface (lower third) was identified more commonly in the AAGR cohort. CONCLUSION: AAGR is faster to learn and perform than AL for the treatment of recurrent anterior shoulder instability with significant glenoid bone loss. The current study found higher rates of desired graft positioning for AAGR clusters.

5.
Orthop J Sports Med ; 6(9): 2325967118795404, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30238013

RESUMO

BACKGROUND: An arthroscopic technique for anatomic glenoid reconstruction has been proposed for the treatment of glenohumeral bone loss in patients with recurrent shoulder instability. This technique is proposed as an alternative to open techniques as well as to the technically challenging arthroscopic Latarjet procedure. In arthroscopic anatomic glenoid reconstruction, a distal tibial allograft is inserted through a novel far medial portal, superior to the subscapularis tendon and lateral to the conjoint tendon. PURPOSE: To evaluate the safety of the far medial arthroscopic portal for anatomic glenoid reconstruction in a cadaveric study. STUDY DESIGN: Descriptive laboratory study. METHODS: Ten cadaveric shoulder specimens were dissected after inside-out medial arthroscopic portal insertion in the lateral decubitus position for arthroscopic anatomic glenoid reconstruction. A single observer performed 3 measurements on each specimen with a digital caliper (to the nearest 0.1 mm) from the medial portal to neurovascular structures, and the mean (±SD) and the range were calculated. The anthropometric data of the cadaveric specimens were also collected. RESULTS: The mean distances between the far medial arthroscopic portal and sensitive anatomic structures were as follows: 50.79 ± 13.69 mm from the musculocutaneous nerve, 46.28 ± 9.64 mm from the axillary nerve, 6.71 ± 8.52 mm from the cephalic vein, and 48.52 ± 7.22 mm from the subclavian artery and vein. The mean size of the medial arthroscopic portal was 25.60 mm. In all cases, the subscapularis muscle was intact. CONCLUSION: The far medial arthroscopic portal for anatomic glenoid reconstruction without a subscapularis split presents a minimal risk to most neurovascular structures during bony reconstruction of the glenoid surface in patients with anterior shoulder instability. The only anatomic structure at risk is the cephalic vein, while the axillary and musculocutaneous nerves are at a safe distance away from the portal, based on previous shoulder arthroscopic portal safety studies in the literature. CLINICAL RELEVANCE: Arthroscopic anatomic glenoid reconstruction using a distal tibial allograft is increasing in popularity for the treatment of anterior shoulder instability with significant bone loss. Being a relatively new technique, the safety of it has yet to be established. This study aimed to demonstrate the safety of a new portal used for arthroscopic anatomic glenoid reconstruction.

6.
Orthop J Sports Med ; 6(5): 2325967118774507, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29854863

RESUMO

BACKGROUND: The results of arthroscopic anterior labral repair have demonstrated high failure rates in patients with significant glenoid bone loss. Several reconstruction procedures using a bone graft have been developed to overcome bone loss. PURPOSE: The primary objective of this study was to generate a safety profile for arthroscopic anatomic glenoid reconstruction using a distal tibial allograft. The secondary objective was to evaluate the radiological outcomes of patients who underwent this procedure. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This retrospective review included the medical charts and diagnostic images of 42 consecutive patients who underwent arthroscopic shoulder stabilization by means of capsule-labral reattachment and bony augmentation with a distal tibial allograft. The safety profile was measured by detecting intraoperative or postoperative complications, including neurovascular (nerves and blood vessels) injuries, bleeding, infections, and dislocations. A radiological evaluation was conducted by assessing computed tomography (CT) scans obtained preoperatively and at approximately 6 months postoperatively. RESULTS: A total of 42 patients (29 male, 13 female) with a mean age of 26.73 ± 9.01 years were included. An excellent safety profile was observed, with no intraoperative complications, neurovascular injuries, adverse events, bleeding, or infections. CT bone scans were obtained for 31 patients, and the mean follow-up for CT scanning (to measure resorption and union) was 6.31 ± 1.20 months (range, 6-7.5 months). There were no cases of nonunion or partial union. Thirteen patients (42%) had no resorption, whereas 13 (42%) and 5 (16%) patents had <50% and ≥50% resorption, respectively. CONCLUSION: Arthroscopic shoulder stabilization with distal tibial allograft reconstruction is a safe operative procedure with a minimal risk to neurovascular structures. Most patients had a healed allograft, but 16% of patients had ≥50% resorption on CT at 6 months. Studies with a longer follow-up are recommended for better assessment of the safety profile.

7.
Radiol Case Rep ; 12(3): 564-570, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28828128

RESUMO

Extraskeletal chondroma is a rare benign tumor with symptoms that could mimic other common musculoskeletal pathological entities. We present a rare case of an extraskeletal para-articular chondroma of the first metatarsophalangeal joint which was initially misinterpreted as joint synovitis, based on magnetic resonance imaging findings. Histology revealed benign chondroma of the foot, which was finally treated with radical surgical excision. More than 2 years postoperatively, no recurrence of the tumor has been encountered.

8.
Clin J Sport Med ; 27(3): 278-282, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28448428

RESUMO

OBJECTIVE: To ascertain whether therapeutic ultrasound (TUS) can be used to assess the progression of conservative management in navicular stress injuries. DESIGN: This is a prospective, clinical case series. Level of evidence IV. SETTING: All participants were examined and followed up in a private Sports Injury Clinic. PARTICIPANTS: Ten elite track and field athletes with severe dorsal midfoot pain over the navicular bone participated in this study. INTERVENTIONS: All patients underwent both TUS and magnetic resonance imaging (MRI) evaluation. The painful threshold of TUS on initial evaluation was a mean of 0.707 ± 149 W/cm, and MRI detected a navicular stress injury in all patients. The athletes received conservative treatment and underwent sequential TUS evaluations at 4, 8, 12 and 16 weeks. MAIN OUTCOME MEASURES: Therapeutic ultrasound pain threshold values were recorded, and the patients were additionally asked to grade local tenderness on a Visual Analogue Scale. Time to return to play was also recorded. RESULTS: The level of pain produced by the application of TUS on a navicular stress fracture seemed to correlate well with Visual Analogue Scale scores and the grade of fracture demonstrated on MRI. The initial low TUS painful mean value increased to a normal mean value of 1.97 ± 0.067 W/cm by 16 weeks. When clinical and TUS findings had returned to normal, the patients were allowed to return to sports activities, with no recurrences experienced during the study period. CONCLUSIONS: The production of pain associated with the application of TUS on a navicular stress fracture is a safe and reproducible method of monitoring the resolution of these fractures. We have used it successfully in making return-to-play decisions for elite level track and field athletes.


Assuntos
Traumatismos em Atletas/terapia , Traumatismos do Pé/terapia , Fraturas de Estresse/terapia , Terapia por Ultrassom , Atletas , Humanos , Imageamento por Ressonância Magnética , Limiar da Dor , Estudos Prospectivos , Ossos do Tarso/lesões , Atletismo
9.
Stud Health Technol Inform ; 224: 108-13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27225563

RESUMO

The development of platforms that are able to continuously monitor and handle epileptic seizures in a non invasive manner is of great importance as they would improve the quality of life of drug resistant epileptic patients. In this work, a device and a computational platform is presented for acquiring low noise electroencephalographic signals, for the detection/prediction of epileptic seizures and the storage of ictal activity in an electronic personal health record. In order to develop this platform, a systematic clinical protocol was established including a number of drug resistant children from the University Hospital of Heraklion. Dry electrodes with innovative micro-spike design were proposed in order to increase the signal to noise ratio of the recorded EEG signals. A wearable low cost platform and its corresponding wireless communication protocol was developed focus on minimizing the interference with the patient's body. A computational subsystem with advanced algorithms provides detection/anticipation of upcoming seizure activity and aims to protect the patient from an accident due to a seizure or to improve his/her social life. Finally, the seizure activity information is stored in an electronic health record for further clinical evaluation.


Assuntos
Eletroencefalografia/instrumentação , Epilepsia/diagnóstico , Convulsões/diagnóstico , Algoritmos , Eletrodos , Eletroencefalografia/métodos , Registros Eletrônicos de Saúde , Epilepsia/patologia , Humanos , Monitorização Ambulatorial/instrumentação , Monitorização Ambulatorial/métodos , Convulsões/patologia , Dispositivos Eletrônicos Vestíveis
10.
Data Integr Life Sci ; 9162: 37-51, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26688837

RESUMO

In many scientific domains, including neuroimaging studies, there is a need to obtain increasingly larger cohorts to achieve the desired statistical power for discovery. However, the economics of imaging studies make it unlikely that any single study or consortia can achieve the desired sample sizes. What is needed is an architecture that can easily incorporate additional studies as they become available. We present such architecture based on a virtual data integration approach, where data remains at the original sources, and is retrieved and harmonized in response to user queries. This is in contrast to approaches that move the data to a central warehouse. We implemented our approach in the SchizConnect system that integrates data from three neuroimaging consortia on Schizophrenia: FBIRN's Human Imaging Database (HID), MRN's Collaborative Imaging and Neuroinformatics System (COINS), and the NUSDAST project at XNAT Central. A portal providing harmonized access to these sources is publicly deployed at schizconnect.org.

11.
Clin Exp Pharmacol Physiol ; 41(12): 1031-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25115333

RESUMO

Observational studies indicate that psychological stress may contribute to the pathogenesis of hypertension and this may be further accentuated by factors such as endothelial dysfunction. On this basis, we aimed to determine whether oxidative stress enhances pressor responses to stressful stimuli and whether augmenting endothelial function by increasing the transport of L-arginine can counter the effects of oxidative stress. Telemetry probes were used to measure mean arterial pressure (MAP) in wild-type (WT; n = 6) and endothelial cationic amino acid transporter-1 (CAT-1)-overexpressing (CAT+) mice (n = 6) before and during an aversive (restraint) and non-aversive (almond feeding) stressor. The superoxide dismutase inhibitor diethyldithiocarbamic acid (DETCA; 30 mg/kg per day; 14 days) was then administered via a minipump to induce oxidative stress. Stress responses to feeding and restraint were repeated during Days 11-12 of DETCA infusion. In WT mice, pressor responses to restraint and feeding were augmented during infusion of DETCA (35 ± 1 and 28 ± 1 mmHg, respectively) compared with respective pretreatment responses (28 ± 2 and 24 ± 1 mmHg, respectively; P ≤ 0.01). In CAT+ mice, pressor responses to feeding were blunted during DETCA (20 ± 1 mmHg) compared with the control response (23 ± 1 mmHg; P = 0.03). In these mice, pressor responses to restraint were similar before (28 ± 1 mmHg) and during (26 ± 1 mmHg) DETCA infusion (P = 0.26). We conclude that endothelial CAT-1 overexpression can counter the ability of oxidative stress to augment pressor responses to behavioural stress.


Assuntos
Pressão Sanguínea/genética , Transportador 1 de Aminoácidos Catiônicos/genética , Células Endoteliais/metabolismo , Estresse Oxidativo/genética , Animais , Arginina/genética , Pressão Sanguínea/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Hipertensão/genética , Camundongos , Camundongos Transgênicos , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/genética , Vasoconstritores/farmacologia
12.
Skeletal Radiol ; 43(1): 65-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23851584

RESUMO

McFarland fractures represent a type of oblique medial malleolar fracture in children that can be challenging to diagnose and treat. A 14-year-old junior league soccer player with a Salter Harris type IV McFarland fracture presented late, as the initial routine two views radiological assessment failed to reveal a clear fracture line. The addition of a mortise ankle view led to the correct diagnosis and subsequent MRI findings guided nonsurgical treatment with an excellent outcome. The debate between obtaining two or three views in closed pediatric ankle injuries according to the so-called Ottawa rules and the usefulness of magnetic resonance imaging (MRI) in the decision making for the choice of treatment of McFarland fractures are discussed in this case report.


Assuntos
Fraturas do Tornozelo , Diagnóstico Tardio , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Posicionamento do Paciente/métodos , Futebol/lesões , Adolescente , Humanos , Masculino
13.
Surg Radiol Anat ; 36(1): 3-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23652480

RESUMO

PURPOSE: This study aimed at summarizing the non-pathologic bony structures which are involved in the pathogenesis of snapping scapula and evaluate their incidence, morphology and correlation to gender, side and age. METHODS: The angulation in the sagittal plane between the supraspinatus and infraspinatus portion of the medial border was measured in 140 dried scapulae. In 264 dried scapulae the medial scapular border morphology was classified into three types and the presence of the Luschka's tubercle and the teres major tubercle or process was recorded. Correlation to gender, side and age was examined using SPSS. RESULTS: The mean angulation between the supraspinatus and infraspinatus portion of the medial border was 154.6° ± 8.8°. Τhe medial scapular border was straight in 99 (37.5 %), convex in 135 (51.1 %) and concave in 30 bones (11.4 %). The Luschka's tubercle was present in eight bones (3 %), while teres major tubercle was found in 114 scapulae (43.2 %). A teres major process was present in 18 bones (6.8 %). The process was curved towards the chest wall in nine bones (3.4 %), while in the other nine scapulae (3.4 %) it had no curvature. CONCLUSIONS: The non-pathologic bony structures which predispose to snapping scapula are not rare and include the concave medial scapular border, the Luschka's tubercle and the teres major process curved towards the chest wall. Orthopaedic surgeons should bear in mind these non-pathologic bony structures in order not to be overlooked during the diagnostic procedure of a snapping scapula since they usually require surgical treatment.


Assuntos
Doenças Musculoesqueléticas/etiologia , Escápula/patologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/patologia , Variação Anatômica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Musculoesqueléticas/patologia , Doenças Musculoesqueléticas/fisiopatologia , Valores de Referência , Escápula/fisiopatologia , Caracteres Sexuais
14.
Surg Radiol Anat ; 36(3): 273-80, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23900507

RESUMO

PURPOSE: To detect the variable relationship between sciatic nerve and piriformis muscle and make surgeons aware of certain anatomical features of each variation that may be useful for the surgical treatment of the piriformis syndrome. METHODS: The gluteal region of 147 Caucasian cadavers (294 limbs) was dissected. The anatomical relationship between the sciatic nerve and the piriformis muscle was recorded and classified according to the Beaton and Anson classification. The literature was reviewed to summarize the incidence of each variation. RESULTS: The sciatic nerve and piriformis muscle relationship followed the typical anatomical pattern in 275 limbs (93.6 %). In 12 limbs (4.1 %) the common peroneal nerve passed through and the tibial nerve below a double piriformis. In one limb (0.3 %) the common peroneal nerve coursed superior and the tibial nerve below the piriformis. In one limb (0.3 %) both nerves penetrated the piriformis. In one limb (0.3 %) both nerves passed above the piriformis. Four limbs (1.4 %) presented non-classified anatomical variations. When a double piriformis muscle was present, two different arrangements of the two heads were observed. CONCLUSIONS: Anatomical variations of the sciatic nerve around the piriformis muscle were present in 6.4 % of the limbs examined. When dissection of the entire piriformis is necessary for adequate sciatic nerve decompression, the surgeon should explore for the possible existence of a second tendon, which may be found either inferior or deep to the first one. Some rare, unclassified variations of the sciatic nerve should be expected during surgical intervention of the region.


Assuntos
Músculo Esquelético/anatomia & histologia , Síndrome do Músculo Piriforme/patologia , Nervo Isquiático/anatomia & histologia , Cadáver , Humanos , Nervo Fibular/anatomia & histologia , Síndrome do Músculo Piriforme/cirurgia , Nervo Tibial/anatomia & histologia
15.
Science ; 336(6082): 704-7, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22491095

RESUMO

Tunneling of electrons through a potential barrier is fundamental to chemical reactions, electronic transport in semiconductors and superconductors, magnetism, and devices such as terahertz oscillators. Whereas tunneling is typically controlled by electric fields, a completely different approach is to bind electrons into bosonic quasiparticles with a photonic component. Quasiparticles made of such light-matter microcavity polaritons have recently been demonstrated to Bose-condense into superfluids, whereas spatially separated Coulomb-bound electrons and holes possess strong dipole interactions. We use tunneling polaritons to connect these two realms, producing bosonic quasiparticles with static dipole moments. Our resulting three-state system yields dark polaritons analogous to those in atomic systems or optical waveguides, thereby offering new possibilities for electromagnetically induced transparency, room-temperature condensation, and adiabatic photon-to-electron transfer.

16.
Muscles Ligaments Tendons J ; 2(4): 267-72, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23738308

RESUMO

To present the results of arthroscopic treatment of patellar tendinopathy in high-level competition athletes. Eleven high-level athletes presented chronic patellar tendinopathy which did not respond to long term conservative treatment. Average age of the patients was 24.8 ±3.4 years old. All patients received an arthroscopic procedure with osteoplasty of the distal patellar pole, debridement of the underlying Hoffa fat pad and of the degenerated areas of the proximal posterior patella tendon and cauterization of the visible neo-vessels. Mean duration of follow-up was 17.4±4 months. Patients showed a major improvement in the Lysholm score from 49.9±5.2 to 92.5±7 and in the VISA P score from 41.2±5.2 to 86.8±14.9 on tenth post-operative week. All patients had returned to sports activities by the twelfth postoperative week. Arthroscopic treatment of chronic patellar tendinopathy found to be a minimal invasive and safe technique which produced satisfactory results.

17.
Nanoscale Res Lett ; 6(1): 88, 2011 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-21711608

RESUMO

The electrical behavior of multi-walled carbon nanotube network embedded in amorphous silicon nitride is studied by measuring the voltage and temperature dependences of the current. The microstructure of the network is investigated by cross-sectional transmission electron microscopy. The multi-walled carbon nanotube network has an uniform spatial extension in the silicon nitride matrix. The current-voltage and resistance-temperature characteristics are both linear, proving the metallic behavior of the network. The I-V curves present oscillations that are further analyzed by computing the conductance-voltage characteristics. The conductance presents minima and maxima that appear at the same voltage for both bias polarities, at both 20 and 298 K, and that are not periodic. These oscillations are interpreted as due to percolation processes. The voltage percolation thresholds are identified with the conductance minima.

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