732 research outputs found
Is Femoral Neck System a Valid Alternative for the Treatment of Displaced Femoral Neck Fractures in Adolescents? A Comparative Study of Femoral Neck System versus Cannulated Compression Screw
No full textBackground and Objectives: The femoral neck system (FNS) is a new minimally invasive internal fixation system for femoral neck fractures (FNFs), but its use has not been reported in adolescents. The aim of this study was to compare the clinical and radiographic outcomes of displaced FNF in adolescents treated with FNS or a cannulated compression screw (CCS). Materials and Methods: A retrospective study of 58 consecutive patients with displaced FNF treated surgically was performed; overall, 28 patients underwent FNS and 30 CCS fixation. Sex, age at injury, type of fracture, associated lesions, duration of surgery, radiation exposure, and blood loss were collected from the hospital database. The clinical and radiographic results, as well as complications, were recorded and compared. Results: The patients were followed up for 16.4 ± 3.1 months on average after index surgery (range, 12 to 24). Consolidation time among patients treated with FNS was significantly lower than those managed by CCS (p = 0.000). The functional scores of patients treated with FNS were significantly higher than those managed by CCS (p = 0.030). Unplanned hardware removal in patients treated with FNS was significantly lower than in those managed by CCS (p = 0.024). Conclusions: FNS has a lower complication rate and better functional outcome than CCS. It may be a good alternative to treat femoral neck fractures in adolescents
Distraction osteogenesis at the proximal third of the ulna for the treatment of Masada type I/IIb deformities in children with hereditary multiple exostoses: a retrospective review of twenty cases
No full textBackgroundUlna distraction by monolateral external fixator (MEFix) is a good option for the treatment of Masada type I and IIb deformities in children with hereditary multiple exostoses (HMEs). However, there is no consensus regarding where to perform ulnar osteotomy. Our hypothesis is that osteotomy at the proximal third of the ulna and progressive distraction with MEFix can simultaneously correct elbow and wrist deformities in patients with HME.MethodsWe retrospectively reviewed patients with HME who underwent ulna distraction osteogenesis from June 2014 to March 2019. The carrying angle (CA), radial articular angle (RAA), ulnar variance (UV), radial variance (RV) and range of motion (ROM) of the affected forearm and elbow were clinically assessed before lengthening and at the last follow-up visit. The total ulna lengthening distance (LD) and radiographic outcome were also recorded.ResultsNineteen patients (20 forearms) with HME aged 9.1 ± 2.4 years at the time of surgery were retrospectively reviewed. The mean follow-up period was 26.1 ± 5.6 months. There were 11 patients (12 forearms) with Masada type I deformities and eight patients (8 forearms) with Masada type IIb deformities. Patients with type IIb deformity had higher RV, lower CA values, less elbow flexion and forearm pronosupination than those with type I deformity (p < 0.05); RV was an independent risk factor for radial head dislocation, with the cut off at RV > 15.5 mm. The mean LDs in patients with type I and type IIb deformities were 33.6 ± 6.6 mm and 41.4 ± 5.4 mm, respectively. The mean CA, UV, RV, forearm pronation and ulna deviation at the wrist improved significantly following surgery in all patients. In particular, five of eight patients (62.5%) with type IIb deformities had concentric reduction of the radiocapitellar joint, while no radial head subluxation was detected in patients with type I deformities at the last follow-up. Three complications were recorded: two pin-track infections and one delayed union.ConclusionsDistraction osteogenesis at the proximal third of the ulna provides satisfactory clinical and radiological outcomes in patients with Masada type I and IIb deformities. Early treatment of Masada type I deformities is indicated before progression to more complex type IIb deformities.Background: Ulna distraction by monolateral external fixator (MEFix) is a good option for the treatment of Masada type I and IIb deformities in children with hereditary multiple exostoses (HMEs). However, there is no consensus regarding where to perform ulnar osteotomy. Our hypothesis is that osteotomy at the proximal third of the ulna and progressive distraction with MEFix can simultaneously correct elbow and wrist deformities in patients with HME. Methods: We retrospectively reviewed patients with HME who underwent ulna distraction osteogenesis from June 2014 to March 2019. The carrying angle (CA), radial articular angle (RAA), ulnar variance (UV), radial variance (RV) and range of motion (ROM) of the affected forearm and elbow were clinically assessed before lengthening and at the last follow-up visit. The total ulna lengthening distance (LD) and radiographic outcome were also recorded. Results: Nineteen patients (20 forearms) with HME aged 9.1 ± 2.4 years at the time of surgery were retrospectively reviewed. The mean follow-up period was 26.1 ± 5.6 months. There were 11 patients (12 forearms) with Masada type I deformities and eight patients (8 forearms) with Masada type IIb deformities. Patients with type IIb deformity had higher RV, lower CA values, less elbow flexion and forearm pronosupination than those with type I deformity (p < 0.05); RV was an independent risk factor for radial head dislocation, with the cut off at RV > 15.5 mm. The mean LDs in patients with type I and type IIb deformities were 33.6 ± 6.6 mm and 41.4 ± 5.4 mm, respectively. The mean CA, UV, RV, forearm pronation and ulna deviation at the wrist improved significantly following surgery in all patients. In particular, five of eight patients (62.5%) with type IIb deformities had concentric reduction of the radiocapitellar joint, while no radial head subluxation was detected in patients with type I deformities at the last follow-up. Three complications were recorded: two pin-track infections and one delayed union. Conclusions: Distraction osteogenesis at the proximal third of the ulna provides satisfactory clinical and radiological outcomes in patients with Masada type I and IIb deformities. Early treatment of Masada type I deformities is indicated before progression to more complex type IIb deformities
Response to Jacques Caton, MD’s comments on the article “Distraction osteogenesis at the proximal third of the ulna for the treatment of Masada type I/IIb deformities in children with hereditary multiple exostoses: a retrospective review of twenty cases” by Lu et al
No full textRisk factors for unsuccessful reduction of chronic Monteggia fractures in children treated surgically a review of 209 cases
No full textAims
To investigate the risk factors for unsuccessful radial head reduction (RHR) in children with
chronic Monteggia fractures (CMFs) treated surgically.
Methods
A total of 209 children (mean age 6.84 years (SD 2.87)), who underwent surgical treatment for
CMFs between March 2015 and March 2023 at six institutions, were retrospectively reviewed.
Assessed risk factors included age, sex, laterality, dislocation direction and distance, preoperative
proximal radial metaphysis width, time from injury to surgery, reduction method, annular
ligament reconstruction, radiocapitellar joint fixation, ulnar osteotomy, site of ulnar osteotomy,
preoperative and postoperative ulnar angulation, ulnar fixation method, progressive ulnar
distraction, and postoperative cast immobilization. Independent-samples t-test, chi-squared
test, and logistic regression analysis were used to identify the risk factors associated with
unsuccessful RHR.
Results
Redislocation occurred during surgery in 48 patients (23%), and during follow-up in 44 (21.1%).
The mean follow-up of patients with successful RHR was 13.25 months (6 to 78). According to
the univariable analysis, time from injury to surgery (p = 0.002) and preoperative dislocation
distance (p = 0.042) were identified as potential risk factors for unsuccessful RHR. However, only
time from injury to surgery (p = 0.007) was confirmed as a risk factor by logistic regression
analysis. Receiver operating characteristic curve analysis and chi-squared test confirmed that
2D fin field-effect transistors integrated with epitaxial high-k gate oxide
No full textPrecise integration of two-dimensional (2D) semiconductors and high-dielectric-constant (k) gate oxides into three-dimensional (3D) vertical-architecture arrays holds promise for developing ultrascaled transistors1–5, but has proved challenging. Here we report the epitaxial synthesis of vertically aligned arrays of 2D fin-oxide heterostructures, a new class of 3D architecture in which high-mobility 2D semiconductor fin Bi2O2Se and single-crystal high-k gate oxide Bi2SeO5 are epitaxially integrated. These 2D fin-oxide epitaxial heterostructures have atomically flat interfaces and ultrathin fin thickness down to one unit cell (1.2 nm), achieving wafer-scale, site-specific and high-density growth of mono-oriented arrays. The as-fabricated 2D fin field-effect transistors (FinFETs) based on Bi2O2Se/Bi2SeO5 epitaxial heterostructures exhibit high electron mobility (μ) up to 270 cm2 V−1 s−1, ultralow off-state current (IOFF) down to about 1 pA μm−1, high on/off current ratios (ION/IOFF) up to 108 and high on-state current (ION) up to 830 μA μm−1 at 400-nm channel length, which meet the low-power specifications projected by the International Roadmap for Devices and Systems (IRDS)6. The 2D fin-oxide epitaxial heterostructures open up new avenues for the further extension of Moore’s law. © 2023, The Author(s), under exclusive licence to Springer Nature Limited.11Nsciescopu
Significados del desnudo: Pan Yuliang en Hua Hun (1994)
No full textHua Hun (1994) is a biopic about the artist Pan Yuling, directed by Huang Shuqin. The film uses art to explore female agency. This article proposes an analysis of the treatment that both authors gave to the nude and the multiplicity of meanings that they attributed to it. To achieve this, their previous works (in painting and cinema) have been examined for thematic and aesthetic coincidences. Pan Yuliang’s portraits and self-portraits were tools for the construction of the female identity, which under Huang Shuqin’s interpretation, spin a narrative that represents the transgression of the object/subject dynamic, transforming their creator into both and neither, which results in the restitution of her full artistic and personal autonomy.Hua Hun (1994) es un biopic de la artista Pan Yuliang, dirigido por Huang Shuqin. La película utiliza el arte para explorar la autonomía femenina. Este artículo plantea un análisis del tratamiento que estas autoras dieron a la desnudez y la multiplicidad de significados que le atribuyeron. Para ello se ha tratado con sus obras previas (pintura y cine) y buscado coincidencias temáticas y estéticas entre ellas. Los retratos y autorretratos de Pan Yuliang fueron herramientas de construcción de la identidad femenina, que sometidos a la interpretación de Huang Shuqin, urden una narrativa que representa la transgresión de la dinámica del objeto/sujeto, convirtiendo a su creadora en ambos y en ninguno, lo que resulta en la restitución de su plena autonomía artística y personal
Background Values of Soil Heavy Metals in the Huang-Huai-Hai Plain in Henan Province, China
No full textDue to the continuous lack of specific background values (BVs) for soil heavy metals in the Huang-Huai-Hai Plain in Henan province (HPHP), many researchers have used soil heavy BVs specific to Henan Province (HP) or Fluvisols of China (FC) as reference criteria to assess soil heavy metal pollution. However, spatial differences in the soil heavy metal BVs between HPHP, HP, and FC, as well as within the HPHP, remain uncertain, affecting the reliability of evaluation results. A total of 897 surface soil samples were collected from the HPHP, with 336 and 561 samples collected from the southern and northern parts of the Shaying River, respectively. According to the obtained results, the BVs of soil Hg, As, Cd, Cr, Pb, Cu, Zn, and Ni in the HPHP were 0.064, 6.67, 0.129, 53.24, 19.67, 22.87, 64.00, and 26.25 mg·kg−1, respectively. The BVs of soil Hg and Cd were higher than those in HP, Fluvisols in Henan Province, and FC, showing strong and extremely strong levels. The BVs of other soil heavy metals exhibited slight differences from the reference BVs. On the other hand, the BVs of soil Hg, As, Cd, Cr, Pb, Cu, Zn, and Ni were 0.066, 4.11, 0.130, 56.72, 20.97, 23.31, 59.21, and 24.03 mg·kg−1 in the southern part and 0.061, 7.45, 0.129, 51.92, 18.96, 22.72, 66.96, and 27.16 mg·kg−1 in the northern part of the Shaying River, respectively. In addition, there were no significant differences in the Hg and Cd BVs between the two parts. Cu BVs in the southern part were significantly higher than those observed in the northern part, while the As, Zn, and Ni BVs in the northern part were significantly higher than those revealed in the southern part. In contrast, the Cr and Pb BVs in the northern part were significantly lower than those observed in the southern part
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