Neck Length Research Articles

Electrospun Fiber as a Facile Means of Studying Silver Nanowires under Mechanical Stretching

It is a great challenge to study the mechanical property of nanomaterials because it is difficult to get a hold of them and apply force. A convenient alternative method via electrospun fibers is shown, where silica‐coated fivefold twinned silver nanowires are well aligned in the fiber and the fibers are aligned in the membrane to a similar direction of macroscopic stretching. The product silver nanowires show necks whereas the fractured silica shell acts as the internal marker for the extent of stretching. Surprisingly, the stretched neck length depends on the nanowire diameter but is independent of the degree of stretching, indicating that the necks have arrived at a limiting intermediate state, which is otherwise hard to achieve for nanomaterials. The necks are studied by transmission electron aberration‐corrected microscopy and steered molecular dynamics simulation, revealing that the build‐up of dislocations and stacking faults (the Lomer–Cottrell (LC) locks) are responsible for trapping the necks at similar limiting states.

Conical Aortic Neck as a Predictor of Outcome after Endovascular Aneurysm Exclusion: Midterm Results

Conical neck may affect endovascular aneurysm repair (EVAR) outcomes. The aim of this study was to present EVAR neck adverse events [endoleak type Ia (ET Ia) and graft migration], in patients with conical neck morphology compared to patients with non-conical necks. An additional analysis of the factors that may affect neck adverse events in patients with conical necks, during the first postoperative year, was executed. A retrospective analysis of prospective data was conducted, including patients that underwent elective EVAR, between 2017 and 2019. All patients completed the clinical and imaging follow-up of the initial 12months. Regarding imaging, all cases underwent computed tomography angiography (CTA), preoperatively, at the 1st and 12th month of follow-up. Preoperative and postoperative aneurysm anatomic characteristics (supra-renal and infra-renal aortic diameters, aneurysm diameter, neck angle, thrombus, and calcification) were recorded. Proximal neck was defined as the infrarenal aortic segment, with a diameter less than 30mm. Conical neck was any neck with a diameter increase ≥2mm per cm of length (from outer-to-outer aortic wall). The proximal 15mm of the neck length were considered the zone of endograft sealing. Migration was any ≥10mm caudal movement of the endograft, relative to its position detected at the CTA of the first month. Neck adverse events were defined as the composite event of ET Ia and migration. The cohort included 150 patients; 66 (44%) presented conical neck morphology. No significant difference was detected regarding the preoperative anatomic characteristics between the conical and non-conical groups. Only distal (15mm) neck diameter was wider in the conical group (P<0.001). Supra-renal active fixation was used in 63.3% of the total cohort; 59.5% in patients with non-conical necks and 68.2% in patients with conical morphology (P=0.275). Graft oversizing was 18.2% and 18.7% in the non-conical and conical group, respectively (P=0.248). Oversizing >20% was equal between groups [37.8% vs. 33.3%% (P=0.608) while oversizing ≥30% was more common among patients with conical necks (3.5% vs. 10.6%, P<0.001, 3.2 odds ratio, 95% confidence interval: 0.79, 12.91). Regarding ET Ia and migration, no difference was recorded between the groups. In a subanalysis among patients with conical necks, a lower graft migration rate was detected among patients with higher oversizing rate (P=0.037). EVAR may offer similarly good midterm outcomes in patients with conical and non-conical neck anatomy. An oversizing to the higher suggested rate may be preventive of graft migration during the first postoperative year in necks with conical morphology. Aggressive oversizing (>20%) do not offer any benefit regarding the prevention of adverse events among patients with conical necks.

Aligning Orifice of the Renal Artery with Fish-Mouth FIXation Technique During Endovascular Aortic Aneurysm Repair for Hostile Neck Anatomy.

Background: As the success of endovascular aortic aneurysm repair (EVAR) depends on sufficient proximal fixation of the endograft to the aortic wall, the proximal hostile neck anatomy (HNA) is the major potential treatment-limiting factor in EVAR. The Aorfix endovascular stent graft was designed to operate on highly angulated aortic necks. The Aligning Orifice of the Renal artery with fish-mouth FIXation (AORFIX) technique uniquely and accurately aligns the trough part of the proximal stent end with the orifice of the lower renal artery and is used to optimize the proximal fish-mouth design for maximum proximal seal use. Herein, we aimed to evaluate the usefulness of the AORFIX technique for EVAR in patients with HNA. Methods: Eighty-one consecutive patients who underwent EVAR with the AORFIX technique (+AORFIX technique group, n = 16) and without (standard group, n = 65) were evaluated. The HNA was defined as any of the following: neck angulation ≥60°, neck length ≤15mm, or neck thrombus or calcification ≥50% of the circumference and conical neck. Results: Each HNA criterion was similar between the two groups. However, the average number of HNA criteria was significantly higher in the +AORFIX technique group (1.9 ± .2 vs. 1.3 ± .1; P < .01). The two groups showed 100% procedural success. The concurrent renal angioplasty and stenting rates (88% vs. 4.6%; P < .01) were significantly higher in the +AORFIX technique group. There were no 30-day deaths in either group and no in-hospital device-related events in the +AORFIX technique group. The median follow-up period was 39months, and there was no significant between-group difference in freedom from reintervention rate (+AORFIX group vs. standard group, 100% vs. 91.0%; P = .327). Conclusion: EVAR using the AORFIX technique might be useful even in patients with more complex HNA.

Clinical analysis of extended PFNA combined with MIPPO plate for reconstruction of lateral wall in treatment of AO-A3.3 intertrochanteric fracture

To compare the clinical efficacy of lengthened proximal femoral nail anti-rotation(PFNA) combined with minimally invasive percutaneous plate osteosynthesis(MIPPO) and common PFNA in the treatment of AO-A3.3 intertrochanteric fracture. The clinical data of 58 patients with AO-A3.3 intertrochanteric fracture treated from January 2015 to April 2020 were retrospectively analyzed. Among them, 27 patients were treated with extended PFNA + MIPPO plate to reconstruct the lateral wall (group A), and 31 patients were treated with closed reduction and PFNA fixation (group B). The bleeding volume, operation time, femoral neck length and tip apex distance(TAD), fracture healing time and postoperative complications were observed and compared between two groups. Harris score was used to evaluate hip joint function 10 months after operation. All patients were followed up for 12 to 28 months. The incision healed well after operation. The bleeding volume and operation time of group A were significantly more than that of group B (P<0.05), and the fracture healing time of group A was significantly less than that of group B(P<0.05). There was no significant difference in the length of femoral neck between two groups at 2 days after operation(P>0.05). The length of femoral neck at 6 months after operation in each group was shorter than that at 2 days after operation(P<0.05), and the shortening of femoral neck at 6 months after operation in group B was significantly shorter than that in group A(P<0.05). There was no significant difference in TAD values between two groups at the same time point(P>0.05) at 2 days and 6 months after operation. There was no significant difference in TAD values between 2 days and 6 months after operation(P>0.05). The incidence of complications in group B was significantly higher than that in group A(P<0.05). The Harris scores of hip joint function in group A were higher than those in group B 10 months after operation (P<0.05). Compared with the treatment of AO-A3 femoral intertrochanteric fracture with closed reduction and PFNA fixation, the lengthened PFNA combined with MIPPO small plate for reconstruction and fixation of the lateral wall can promote the fracture healing, improve the patient's functional recovery, and significantly reduce the complications.

The influence of urbanization on the morphology of the Barak River floodplain in Cachar District, Assam

AbstractIn the present study, the meandering behavior of the Barak River (Cachar), Assam was traced. Flow path length, meander neck length, sinuosity index, and river migration were determined segment-by-segment to demonstrate morphological changes. Decadal land-use land cover (LULC) maps were also prepared at the section scale using Landsat data (1990–2020) validated with the Kappa coefficient to characterize changes along alluvial floodplains. Urban growth and agricultural activities affect river morphology, especially where intensive agriculture was recorded, according to LULC studies. Due to urbanization, forestation constantly decreased, causing river variability. According to the results of the present study, river migration is very slow between Sec 1 and Sec 3. In terms of river stability, the parts are more stable, particularly Sec 1, which features less urbanization and agricultural activity than the other sections. The most vulnerable segments within the study area were considered to be Sec 2 and 4. There is a rather large amount of migration within sections, especially segments CC and GG. The river segments became more vulnerable as a new oxbow lake was formed and LULC changed over a decade. This stretch of Barak is characterized by a broad alluvial floodplain and is shifting since this study applies to various meandering types.

Digital Templating of THA Using PACS and an iPhone or iPad is as Accurate as Commercial Digital Templating Software.

Digital templating is a standard preoperative planning method in THA. Unfortunately, many hospitals cannot afford the software or have accessibility barriers owing to a limited number of installed computer workstations. We created a templating method using a picture archiving and communication system and the Keynote program on a mobile phone. The method's accuracy and reliability have not been compared with those of commercial digital templating software. (1) How accurate is this novel method on iPhone and iPad mobile devices compared with a commercially available digital templating software program? (2) Is the method reproducible among users with different levels of experience? (3) Are the results similar for different types of femoral prostheses? Between January 2017 and May 2020, we treated 209 patients for hip disease or trauma with primary cementless THA. We considered patients with a normal contralateral hip as potentially eligible for this retrospective study. Thus, 91% (191 of 209 hips) were eligible; a further 13% (27 hips) were excluded because of postoperative leg length discrepancy > 5 mm, femoral offset discrepancy > 5 mm (9% [18 hips]), intraoperative periprosthetic fracture (4% [eight hips]), and proximal femoral deformity (0.5% [one hip]), leaving 78% (164 hips) for analysis here. Their preoperative radiographs were evaluated by three independent assessors, including one senior orthopaedic surgeon, one senior resident, and one junior resident, using three methods. The first was digital templating using OrthoView software, which is a commercially available digital templating software program used worldwide and known to possess high accuracy. The other two methods were technically similar to one another, with the only difference being the interface: iPhone versus iPad. In both of those approaches, using the picture archiving and communication system measurement tool, we drew a circle on an acetabular radiograph to depict the cup. We took a photograph of the computer display and imported the photograph into slides of the Keynote program, a presentation software application for Mac computers, on both devices. It was then underlaid on transparent digital templates of the femoral stem, which were scanned from plastic templates and positioned at the center of each slide. We scaled the image to the template by adjusting the image size until a 15-cm straight line on the hip photograph was equal to the 15-cm scale markers of the template. All templating results were compared with the actual implanted cementless THA components to assess accuracy. All assessors were blinded to the information about the actual implants, and they were not involved in performing the surgical procedures. The intrarater and interrater reliabilities were analyzed using intraclass correlation coefficients and kappa values. The accuracy for predicting stem size for each type of the four stem designs was compared among the three methods. We were able to predict the acetabular cup size within one size in 92% of hips (151 of 164) using OrthoView and in 92% (150 of 164) using the novel method (p > 0.99). The accuracies of the three methods were comparable for predicting a femoral stem size within one size (OrthoView: 90% [148 hips], iPhone: 93% [152 hips], and iPad: 91% [149 hips]; p = 0.78), and neck length (OrthoView: 96% [157 hips], iPhone: 96% [158 hips], and iPad: 97% [159 hips]; p = 0.95). Using OrthoView, the neck offset was correctly predicted in 80% (132 hips), compared to 85% (139 hips) when using the iPhone and 82% (134 hips) when using the iPad (p = 0.57). All methods showed substantial or excellent agreement regarding intrarater and interrater reliability. There was no difference in accuracy regarding any of the four femoral stem designs we evaluated (Avenir, Excia, ML taper, and Metha). The digital templating technique for THA using an iPhone or iPad combined with a picture archiving and communication system demonstrated high accuracy, comparable to that of commercial digital templating software. This technique is reliable and reproducible for predicting a cementless prosthesis size, neck length, and offset in different types of femoral stems. It may be useful as an alternative in resource-constrained centers where commercial software programs are too expensive to be used in practice. Level IV, diagnostic study.

Morphological and molecular characterisation of Talanema ibericum sp. n. (Dorylaimida, Qudsianematidae) from southern Iberian Peninsula

Summary A new species of the genus Talanema, T. ibericum sp. n., collected in natural areas of southeastern Iberian Peninsula, is characterised, including morphological description, line, LM and SEM illustrations, and molecular (18S, D2-D3 28S rDNA sequences) study. The new species is distinguished by its 1.27-1.59 mm long body, lip region offset by constriction and 14-16.5 μm wide with perioral liplets, odontostyle 16.5-19.5 μm long, neck 285-359 μm long, pharyngeal expansion occupying 42-48% of the total neck length, uterus tripartite and 147-228 μm long or 2.6-4.0 body diam., vulva transverse (V = 53-59), presence of cuticular irregularities at both sides of vulva, female tail conical with a dorsal concavity (27-40 μm, c = 36-54, c′ = 1.0-1.3), male tail short and rounded conoid (24 μm, c = 66, c′ = 0.8), spicules 58 μm long, and 17 almost contiguous ventromedian supplements with hiatus. Morphological and molecular data reveal that the new species is similar to (but easily separable from) T. baqrii, with which it is compared. Present results support the monophyly of the genus Talanema.

Phenotypic Characterization of Sheep Population in Aures, Hodna and Ziban Zones, Algeria

This study aims to characterize the sheep population phenotypically in three zones in northeastern Algeria: Aures, Hodna and Ziban. A total of 160 female animals of 2 to 4 years of age were subject to 4 quantitative linear body measurements (body length BL, withers height WH, tail length TL and wool weight WW) and 9 qualitative physical traits (head length HL, ear orientation EO, horn presence H, neck length NL, wool extent WE, tail texture TT, eyes shape ES, head color HC and wool color WC). The results indicate that the sheep population in these areas belonged to the Ouled Djellel sheep breed with some abnormal phenotypes, which refers to uncontrolled crossbreeding. Body measurements show moderate variation coefficient values, with the highest value reported for WW (7.37%). However, despite the weak correlations found in this study, clear ones were revealed between WH and TL (0.30) and BL and WW (0.26). The Hierarchical Agglomerative Clustering analysis sub-divided the sheep population into three classes, in which an overlap, according to body measurements, was remarked between Hodna and Ziban and between Aures and Ziban but not between Aures and Hodna.

Spatiotemporal Characterization and Analysis of River Morphology Using Long-Term Landsat Imagery and Stream Power

Meandering rivers are among the most dynamic Earth-surface systems, which generally appear in fertile valleys, the most valuable lands for agriculture and human settlement. Landsat time series and morphological parameters are complementary tools for exploring river dynamics. Karun River is the most effluent and largest meandering river in Iran, which keeps the Karun’s basin economy, agriculture, and industrial sections alive; hence, investigating morphological changes in this river is essential. The morphological characteristics of Karun have undergone considerable changes over time due to several tectonic, hydrological, hydraulic, and anthropogenic factors. This study has identified and analyzed morphological changes in Karun River using a time series of Landsat imagery from 1985–2015. On that basis, morphological dynamics, including the river’s active channel width, meander’s neck length, water flow length, sinuosity index, and Cornice central angle, were quantitatively investigated. Additionally, the correlation between the stream power and morphological factors was explored using the data adopted from the hydrometric stations. The results show that the dominant pattern of the Karun River, due to the sinuosity coefficient, is meandering, and the majority of the river falls in the category of developed meander rivers. Moreover, the number of arteries reduced in an anabranch pattern, and the river has been migrating towards the downstream and eastern sides since 1985. This phenomenon disposes a change in the future that can be hazardous to the croplands and demands specific considerations for catchment management.

Modeling of the respiratory system of the long-necked Triassic reptile Tanystropheus (Archosauromorpha).

All known species of the Triassic archosauromorph genus Tanystropheus are known to have had the longest neck in proportion to their torso. This feature is related to a series of ventilatory challenges since an increase in neck length also increases airway length and, therefore, the volume of stagnant air that does not reach the lungs, the dead space volume. Based on this challenge, the objective of the present study was to model the type of respiratory system of Tanystropheus able to meet its metabolic demands during the early Triassic period. The modeling was based on allometric relations for morphological and physiological ventilatory and metabolic variables, and to do so, the mean body mass of Tanystropheus was estimated based on three different methods. In addition, the tracheal airflow was also estimated based on the proportions of Tanystropheus elongated neck, the results of allometric modeling, and fundamental equations of fluid mechanics. The estimation of the body mass indicated that an animal of 3.6m would possess a body mass of 50.6 ± 21.6kg. Allometric modeling suggested that the respiratory system best suited to Tanystropheus' oxygen demands, especially during activity, would be a generic reptilian-like respiratory system composed of multicameral lungs. The best respiratory pattern to maintain adequate tracheal flow rates and effective pulmonary ventilation would be one ventilating the relatively narrower trachea at lower frequencies to deal with tracheal dead space volume.

Guided Growth Improves Coxa Valga and Hip Subluxation in Children With Hereditary Multiple Exostoses.

In children with severe hereditary multiple exostoses (HME), coxa valga, and hip subluxation are common deformities. The literatures related to surgical management and prevention of hip joint subluxation in HME are scarce. In this study, we aimed to investigate the efficacy of guided growth procedure to correct coxa valga and hip subluxation in HME patients. We retrospectively retrieved 12 patients who received guided growth procedures for coxa valga and hip subluxation in HME patients with proximal femur exostoses with a minimum follow-up time of 2 years between 2012 and 2019. Radiographic parameters include head-shaft angle, Hilgenreiner-epiphyseal angle, acetabular index, Reimer migration percentage, center-edged angle, articulo-trochanteric distance, and femoral neck length for comparison between preoperative and latest follow-up results. It was conducted statistically by paired t test and Wilcoxon signed rank test. In this study, the mean difference between preoperative and latest follow-up was significant in head-shaft angle (12±5 degrees; CI, 10-14; P<0.001), Hilgenreiner-epiphyseal angle (12±5 degrees; CI, 10-15; P<0.001), and MP (7%±8%; CI, 3-11; P=0.001). There was a low revision rate (4 of 21, 19%) and no complication in our study. Compared with previous studies on guided growth in children with cerebral palsy and developmental dysplasia of the hip, our study showed good comparable outcomes. The results indicated that guided growth improves the hip radiographic parameters of children with HME and may prevent coxa valga and hip subluxations. It is a safe procedure and provides predictable results. Level IV; therapeutic, case series.

Comparative clinical study of short-term outcomes between table fenestrated and chimney endovascular aneurysm repair for hostile neck aneurysms.

Hostile neck abdominal aortic aneurysm (AAA) is challenging for standard endovascular aneurysm repair (EVAR). We sought to compare fenestrated endovascular aneurysm repair (fEVAR) and chimney endovascular aneurysm repair (chEVAR) for hostile neck AAA. Patients were identified retrospectively. Hostile neck anatomy was defined as a proximal neck length of <15mm or angulation >60°. The choice of fEVAR or chEVAR was based on neck anatomy and physician preference. Type I endoleak (T1EL) was the primary outcome. Other outcomes included type III endoleak (T3EL), visceral stent occlusion, renal insufficiency, reintervention, and mortality. A total of 84 patients were included from April 2012 to December 2021. fEVAR and chEVAR patients were 48 and 36 cases, respectively. Both groups showed similar rate of T1EL, T3EL, visceral stent occlusion, renal insufficiency, reintervention, and mortality. However, chEVAR patients had a more tortuous neck (61.1% vs. 16.7%, p < 0.001), while fEVAR patients had a greater neck size (29.5 ± 6.3mm vs. 24.5 ± 4.8mm, p < 0.001) and more reconstructing target arteries (2.2 ± 1.1 vs 1.3 ± 0.6, p < 0.001). fEVAR and chEVAR show similar safe and effective outcomes in well-selected hostile neck. fEVAR might be able to reconstruct multiple visceral arteries, and chEVAR seems justified in patients with poor anatomical suitability for fEVAR.

Shape modelling of the oropharynx distinguishes associations with body morphology but not whiplash-associated disorder.

Characterization of the oropharynx, a subdivision of the pharynx between the soft palate and the epiglottis, is limited to simple measurements. Structural changes in the oropharynx in whiplash-associated disorder (WAD) cohorts have been quantified using two-dimensional (2D) and three-dimensional (3D) measures but the results are inconsistent. Statistical shape modelling (SSM) may be a more useful tool for systematically comparing morphometric features between cohorts. This technique has been used to quantify the variability in boney and soft tissue structures, but has not been used to examine a hollow cavity such as the oropharynx. The primary aim of this project was to examine the utility of SSM for comparing the oropharynx between WAD cohorts and control; and WAD severity cohorts. The secondary aim was to determine whether shape is associated with sex, height, weight and neck length. Magnetic resonance (MR) T1-weighted images were obtained from healthy control (n= 20), acute WAD (n= 14) and chronic WAD (n= 14) participants aged 18-39 years. Demographic, WAD severity (neck disability index) and body morphometry data were collected from each participant. Manual segmentation of the oropharynx was undertaken by blinded researchers between the top of the soft palate and tip of the epiglottis. Digital 3D oropharynx models were constructed from the segmented images and principal component (PC) analysis was performed with the PC weights normalized to z-scores for consistency. Statistical analyses were undertaken using multivariate linear models. In the first statistical model the independent variable was group (acute WAD, chronic WAD, control); and in the second model the independent variable was WAD severity (recovered/mild, moderate/severe). The covariates for both models included height, weight, average neck length and sex. Shape models were constructed to visualize the effect of perturbing these covariates for each relevant mode. The shape model revealed five modes which explained 90% of the variance: mode 1 explained 59% of the variance and primarily described differences in isometric size of the oropharynx, including elongation; mode 2 (13%) primarily described lateral (width) and AP (depth) dimensions; mode 3 (8%) described retroglossal AP dimension; mode 4 (6%) described lateral dimensions at the retropalatal-retroglossal junction and mode 5 (4%) described the lateral dimension at the inferior retroglossal region. There was no difference in shape (mode 1 p= 0.52; mode 2 p= 0.96; mode 3 p= 0.07; mode 4 p= 0.54; mode 5 p= 0.74) between control, acute WAD and chronic WAD groups. There were no statistical differences for any mode (mode 1 p= 0.12; mode 2 p= 0.29; mode 3 p= 0.56; mode 4 p= 0.99; mode 5 p= 0.96) between recovered/mild and moderate/severe WAD. Sex was not significant in any of the models but for mode 1 there was a significant association with height (p= 0.007), mode 2 neck length (p= 0.044) and in mode 3 weight (p= 0.027). Although SSM did not detect differences between WAD cohorts, it did detect associations with body morphology indicating that it may be a useful tool for examining differences in the oropharynx.

Potential Metastatic Distance of Lymph Nodes in Different Metastatic Patterns for Nasopharyngeal Carcinoma: Implications for Caudal Border of Elective Nodal Target Volume Delineation

<h3>Purpose/Objective(s)</h3> To investigate the potential metastatic distance of involved lymph nodes (LNs) which can reveal possible pathways of microscopic spread and determine the delineation of caudal border of clinical target volume (CTV) for elective nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). <h3>Materials/Methods</h3> A total of 1412 patients with pathologically-proven NPC between January 2010 and December 2020 were enrolled. The center points of caudal edge of the most caudally involved LN, lateral process of C1, hyoid bone, cricoid cartilage and cranial edge of sternal manubrium were marked on treatment planning CT scans of each patient. The metastatic distance of the most caudally involved LN, lengths of entire neck, level II, III and IV were determined. Metastatic patterns and their respective metastatic distances covering 95% of patients were analyzed. The metastatic distance covering 95% of patients with LN involvement in lower level is recommended as the caudal border of CTV for patients with involved LN in the upper level. Recommendations in this study were compared with consensus guidelines to propose modifications to caudal border of CTV. <h3>Results</h3> In 1412 patients, lengths of level II, III, IV and II + III ranged widely from 2.9-8.4, 1.6-5.5, 1.2-9.6 and 5.5-12.6 cm, accounting for 21%-62%, 9%-41%, 9%-59% and 41%-91% of the entire neck, respectively. A total of 1933 LNs were delineated, LN metastasis was step by step with 1% skipping rate. Six main metastatic patterns were Level II (498, 25.8%), RPLN + II (801, 41.4%), Level II + III/Va (111, 5.7%), RPLN + Level II + III/Va (327, 16.9%), Level II + III/Va + IV/Vb (58, 3.0%) and RPLN + Level II + III/Va + IV/Vb (119, 6.2%), with significantly different mean metastatic distances. Their maximum distance covering 95% patients were 6.0, 6.3, 8.8, 9.8, 12.8, and 13.7 cm, respectively, based on which, caudal borders for metastatic patterns N0, RPLN, Level II, RPLN + Level II, RPLN + Level II, Level II + III/Va, RPLN + Level II + III/Va were recommended. Compared with current recommendations based on anatomic landmarks, the caudal borders of CTV shifted upward in 175 (99.4%) N0 patients, 88 (98.9%) with metastatic RPLN only and all patients with Level II and RPLN + Level II node involvement by 3.2, 2.9, 6.1, and 5.1 cm. However, 9(15.5%) and 6(5.0%) of patients with level III node involvement had lower recommended caudal borders of ENI than cranial edge of sternal manubrium (Table 1). <h3>Conclusion</h3> Delineation of the caudal border of CTV based on anatomical markers is highly heterogeneous and unstable. This study suggests using the potential metastatic distance (representing the metastatic capacity) of LNs in the lower level as the caudal border of CTV when with involved LN in the upper level. It could reduce the CTV volume in most patients, leading to an expected significant reduction in acute and late toxicity. However, potential metastatic distance in some patients suggests a lower CTV caudal border, indicating the anatomical marker-cased recommendation are insufficient.

Flask-like Janus Colloidal Motors with Explicit Direction and Tunable Speed.

Nanoparticles with an anisotropic morphology and composition are flourishing in various scientific fields. Their morphology has a great impact on their functions, but the precise regulation of their growth and final morphology is still challenging. Here, flask-like Janus particles (FJPs) with different compositions segmented on the inner and outer surfaces were fabricated via a sol-gel process using different silane precursors. The neck length of the flask-like particles can be controllably regulated by employing different silane precursors. The Pt catalyst was selectively loaded in their cavities, and as-formed FJPs@Pt are employed as colloidal motors. Due to the adjustable neck length, the Janus colloidal motors have explicit directionality and tunable speeds (max diffusion coefficient is 18.2 μm2 s-1).

Proximal femur geometry: a major predictor of proximal femur fracture subtypes.

Proximal femur geometry (PFG) represents an important risk factor for the occurrence of hip fractures. There are currently few studies regarding the correlation between PFG and the occurrence of a specific fracture subtype, and those that exist have small cohorts and present with different methodologies and contradictory results. Therefore, there is no consensus in the literature regarding this topic. The present study aimed to establish the contribution of the PFG in the occurrence of different subtypes of proximal femur fractures (PFF): intertrochanteric, neck and subtrochanteric. Analysis of 1022 plain anteroposterior pelvic radiographs of patients consecutively admitted to the emergency room of a Level 1 Trauma Centre between 2013 and 2019 after low energy trauma who presented with PFF and underwent surgical treatment. Patients were analysed considering age, gender and subtype of PFF (intertrochanteric, neck or subtrochanteric). Radiological parameters including cervicodiaphyseal angle (CDA), horizontal offset (HO), femoral neck width (FNW), femoral neck length (FNL), great trochanter-pubic symphysis distance (GTPSD), acetabular teardrop distance (ATD) and width of the intertrochanteric region (WIR) were measured and compared between the different subtypes of fractures (7154 measurements). Statistical analysis was conducted recurring to absolute measurements and measurements ratios. The correlation was assessed using t-test. There were statistically significant differences in proximal femur geometry between the different subtypes of fractures. Patients presenting with femoral neck fractures had greater CDA (132.5 ± 6.9 vs. 130.0 ± 7.3; p < 0.001) and lower HO (45.8 ± 7.4 vs. 49.0 ± 8.0; p < 0.001), HO/ATD (0.34 ± 0.068 vs. 0.37 ± 0.072; p < 0.001) and HO/GTPSD (0.26 ± 0.049 vs. 0.28 ± 0.039; p < 0.001) than patients with intertrochanteric/subtrochanteric fractures. PFG represents an important contributor to the occurrence of different fracture subtypes. Femoral neck fractures are associated with greater CDA and lower HO, HO/ATD and HO/GTPSD when compared to intertrochanteric or subtrochanteric fractures.

Effect of Radiocapitellar Joint Over/Under Stuffing on Elbow Joint Contact Pressure

Comminuted radial head fractures are commonly treated by surgical resection or replacement with a prosthesis. A potential problem with radial head replacement is overlengthening of the radial neck ("overstuffing" of the radial head), which has been shown to affect both ulnohumeral kinematics and radiocapitellar pressures. We hypothesized that an overstuffed radial head prosthesis increases capitellar pressure and reduces coronoid pressure. Seven human cadaveric elbows were prepared on a custom-designed apparatus simulating stabilizing muscle loads, and passively flexed from 0° to 90° under gravity valgus torque while joint contact pressures were measured. Each elbow was tested sequentially with different neck lengths, starting with the intact specimen followed by insertion of understuffed (-2 mm), standard-height (0 mm), and overstuffed (+2 mm) radial head prostheses in neutral forearm rotation, 40° pronation, and 40° supination positions, respectively. Capitellar mean contact pressures significantly increased after insertion of an overstuffed radial head prosthesis. In valgus position with neutral forearm rotation, capitellar mean contact pressure on the joint with an intact radial head averaged 227 ± 70 kPa. Insertion of understuffed, standard-height, and overstuffed radial head prostheses changed the mean contact pressures to 152 ± 76 kPa, 212 ± 68 kPa, and 491 ± 168 kPa, respectively. The overstuffed radial head group had significantly lower whole coronoid mean contact pressures (153 ± 56 kPa) compared with the intact (390 ± 138 kPa) and standard-height (376 ± 191 kPa) radial head groups. An increase in radial prosthesis height significantly increases capitellar contact pressures and reduces coronoid contact pressures. Restoration of the anatomic radial head height is critical when performing radial head arthroplasty to maintain normal joint biomechanics. Elevated capitellar contact pressures can potentially lead to pain and early degenerative changes.

The Effect of EndoAnchors on Aneurysm Sac Regression for Patients Treated With Infrarenal Endovascular Repair With Hostile Neck Anatomies: A Propensity Scored Analysis

Purpose: To analyze sac evolution patterns in matched patients with hostile neck anatomy (HNA) treated with standard endovascular aneurysm repair (sEVAR) and endosutured aneurysm repair (ESAR). Methods: Observational retrospective study using prospectively collected data between June 2010 and December 2019. ESAR group data were extracted from the primary arm of the PERU registry with an assigned identifier (NCT04100499) at 8 centers and those from the sEVAR came from 4 centers. Suitability for inclusion required: no proximal endograft adjuncts (besides EndoAnchor use), ≤15 mm neck length and minimum of 12-months follow-up imaging. Bubble-shaped neck (noncylindrical short neck with discontinuous seal) aspect was analyzed. Both groups were analyzed using propensity score matching (PSM) for aortic neck length, width, angulation, and device fixation type. Main outcome assessed was sac evolution patterns (sac expansion and regression were defined as >5mm increase or decrease, of the maximum sac diameter respectively; all AAAs within this ±5 mm range in diameter change were considered stable) and secondary outcomes were type-Ia endoleaks; other endoleaks and mortality. A power analysis calculation >80% was confirmed for sac regression evaluation. Results: After exclusions, PSM resulted in 96 ESAR and 96 sEVAR patients. Mean imaging follow-up (months) was 44.4±21.3 versus 43.0±19.6 (p=0.643), respectively. The overall number of patients achieving sac regression was higher in the ESAR group (n=57, 59.4% vs n=31, 32.3%; p<0.001) and the cumulative sac regression achieved at 5 years was 65% versus 38% (p=0.003) in favor of the ESAR group. There were no statistically significant differences in type-Ia endoleak and/or other endoleaks. Univariate analysis for sac regression patients in the sEVAR and ESAR group individually showed the bubble-shape neck as a predictor of sac regression failure. There were no statistical differences in overall and aneurysm-related mortality. Conclusion: Endosutured aneurysm repair provided improved rates of sac regression for patients with AAA and HNA when compared with sEVAR at midterm and up to 5 years, despite similar rates of type-Ia endoleaks, and the need to consider some important limitations. The presence of bubble-shaped neck was a predictor of sac regression failure for both groups equally. Clinical Impact The use of EndoAnchors aids and improves EVAR treatment in hostile neck anatomies by an increased rate of sac regression when compared to EVAR treatment alone in up to 5 year analysis. Moreover, a trend to reduced number of type Ia endoleaks is also achieved, although not significant in the present study. This data, adds to current and growing evidence on the usefulness of EndoAnchors for AAA endovascular treatment.

Are CPR (Contact Patch to Rim) distance anomalies associated with the occurrence of abnormal noises from ceramic-on-ceramic THA?

IntroductionThe ceramic-on-ceramic couple in total hip arthroplasties (THA) has the advantage of excellent wear resistance and the bioinert nature of its debris. Noise occurring from this friction torque is a common complication, the contributing factors of which are debated. The noise is caused by a lack of lubrication, due in most part to the positioning of the acetabular cup. The study of metal-on-metal couples identified that the calculation of the Contact Patch to Rim (CPR) distance provides information on lubrication defects and also that it is correlated with the wear of metal-on-metal implants. This CPR distance is not recognized to be correlated with the occurrence of noise for the ceramic-on-ceramic couple at a caliber ≤ 36mm. We therefore conducted a retrospective case-control study to assess: 1) The influence of the CPR distance on noise occurrence; 2) Whether other factors associated to noise occurrence exist? HypothesisOur hypothesis was that a low CPR distance was correlated with noise occurrence. MethodThis was a case-control study with 3 controls for each case, analyzing 21 THAs (21 patients) with noise compared to 63 THAs without noise (63 patients) matched for age, sex and body mass index. These patients were taken from a continuous retrospective series of 96 patients for 104 total hip arthroplasties (THA) with a single operator and 4th generation Biolox Delta ceramic-on-ceramic single implant, performed between 2007 and 2012. The calculation of the CPR distance was then performed for both groups using measurements of inclination angles, anteversion angles, and implant data regarding the head/insert contact angle, head/insert diameter and clearance. ResultsAt the mean follow-up of 7.1 years±1.2 [5 to 9.6], the mean CPR distance was lower in the noise group 10mm±3.3 [3.8 to 16.4] than in the control group 14.8mm±4.3 [7.3 to 24.4] (p=0.0007). The mean inclination angle was higher in the noise group 45.1°±7.8 [31 to 62] than in the control group 41.2°±7.2 [26 to 56] (p=0.04). The occurrence of noise was independent of anteversion, head caliber, cup diameter, neck length and stem size, and stem type (standard or lateralized). ConclusionA low CPR distance was correlated with the occurrence of noises, similarly a steep inclination was correlated with the occurrence of noises. Level of evidenceIII; Retrospective case-control study.

Morphometric measurements and the relationship with body weight in the Sudanese Dorcas Gazelle and Bohor Reedbuck

The objectives were to describe the morphometric measurements and determine the best model for estimating the relationship between body weight and morphometric measurements of the two Sudanese antelopes, Dorcas Gazelle (Gazella dorcas) and Bohor Reedbuck (Redunca redunca). Twenty-four animals belonging to two Sudanese antelope species, six males and six females from each species were used. Data on body weight and body measurements were recorded from each species. Averages of body weight and morphometric traits of Bohor Reedbuck were larger than the corresponding values of Dorcas Gazelle, while the opposite was true in the case of horn thickness, which was larger in the later. Stepwise regression analysis indicated that, the best model for Dorcas Gazelle had the variables neck length, belly girth and chest height, while Bohor Reedbuck had body length, head length, neck length, tail length, chest girth and pelvic height. These variables explained 82% of the total variation in body weight of Dorcas Gazelle, and 92% of the variation of Bohor Reedbuck. These results are discussed in relation to morphometric measurements reported for antelopes elsewhere.