scholarly journals The oblique triangle configuration of three parallel screws for femoral neck fracture fixation using computer-aided design modules

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Ru Yi Zhang ◽  
Jian Tao Li ◽  
Jing Xin Zhao ◽  
Zhe Zhao ◽  
Li Cheng Zhang ◽  
...  
Keyword(s):  
Femoral Neck ◽  
Cross Section ◽  
Computer Aided Design ◽  
Spatial Configuration ◽  
Evaluation Model ◽  
Femoral Neck Fractures ◽  
Sectional Area ◽  
Cross Sectional ◽  
Torsion Angles ◽  
Aided Design

AbstractClosed reduction and internal fixation with three cannulated compression screws is a common method for treating femoral neck fractures in young and middle-aged patients. Protocols including the inverted triangle configuration and dispersion of the screws still needed further supports. The purpose of this study was to explore a novel oblique triangle configuration (OTC) of three screws in fixing femoral neck fractures based on the morphology of the femoral neck isthmus (FNI). The computer-aided design modules were used to explore the ideal spatial configuration with largest triangle by three parallel screws. A univariate evaluation model was established based on the oval-like cross-section of the FNI. When the three screws were positioned by the OTC, Inverted Equilateral Triangle Configuration (IETC), and the Maximum Area Inverted Isosceles Triangle Configuration (MA-IITC) respectively, the proportion of area and circumference in the cross-section of FNI and the changing trend of proportion were compared under various torsion angles, eccentricity, and cross-sectional area of FNI. The area and circumference ratios of the parallel screws using the OTC method were significantly higher than in the IETC and MA-IITC groups. In the univariate evaluation model, the OTC area ratio and circumference ratio remained stable under the different femoral neck torsion angles, FNI cross-sectional area, and eccentricity. The OTC method provided an ideal spatial configuration for the FNA fixation with the largest area using three parallel screws. The position of the posterior screw was also away from the metaphyseal artery, potentially reducing the possibility of vascular injury and screw penetrating.

scholarly journals A Novel 3D-Printed Device for Precise Percutaneous Placement of Cannulated Compression Screws in Human Femoral Neck Fractures

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Cheng Long ◽  
Jin-hai Liu ◽  
Xiang-ping Chai ◽  
Xiang-feng Liu ◽  
Zhi-xi Duan
Keyword(s):  
3D Printing ◽  
Femoral Neck ◽  
Proximal Femur ◽  
Computer Aided Design ◽  
Femoral Neck Fractures ◽  
X Ray ◽  
Guide Plate ◽  
Computer Aided ◽  
3D Printed ◽  
Aided Design

Background. The aim of this study was to investigate the application of computer-aided design and 3D printing technology for percutaneous fixation of femoral neck fractures using cannulated compression screws. Methods. Using computed tomography data, an individualized proximal femur model was created with a 3D printer. The reduction of the femoral neck fracture and the placement of the cannulated compression screws were simulated on a computer. A 3D printing guide plate was designed to match the proximal femur. After demonstrating the feasibility of the 3D model before the surgical procedure, the guide needles and cannulated compression screws were inserted with the aid of the 3D-printed guide plate. Results. During the procedure, the 3D-printed guide plate for each patient matched the bone markers of the proximal femur. With the aid of the 3D-printed guide plate, three cannulated compression screws were accurately inserted into the femoral neck to treat femoral neck fractures. After screw placement, intraoperative X-ray examination showed results that were consistent with the preoperative design. The time taken to complete the procedure in the guide plate group was 35.3 ± 2.1   min , the intraoperative blood loss was 6.3 ± 2.8   mL , and X-ray fluoroscopy was only performed 9.1 ± 3.5 times. Postoperative radiographs showed adequate reduction of the femoral neck fractures. The entry point, entry direction, and length of the three cannulated compression screws were consistent with the preoperative design, and the screws did not penetrate the bone cortex. Conclusion. Using computer-aided design and 3D printing technology, personalized and accurate placement of cannulated compression screws can be realized for the treatment of femoral neck fractures. This technique can shorten the time required for the procedure and reduce damage to the femoral neck cortex, intraoperative bleeding, and the exposure of patients and healthcare staff to radiation.

scholarly journals Functional Outcome of Intracapsular Femoral Neck Fractures Treated by Bipolar Hemiarthroplasty

2021 ◽  
Vol 15 (5) ◽  
pp. 988-991
Author(s):  
Zamir Hussain Tunioi ◽  
Rizwan Ali Jhatiyal ◽  
M Azeem Akhund ◽  
M Kashif Abbasi ◽  
L Das Maheshwari ◽  
...  
Keyword(s):  
Femoral Neck ◽  
Functional Outcome ◽  
Femoral Neck Fractures ◽  
University Hospital ◽  
Harris Hip Score ◽  
Bipolar Hemiarthroplasty ◽  
Neck Of Femur ◽  
Cross Sectional ◽  
Average Hospital

Aim: To evaluate the functional outcome of bipolar hemiarthroplasty in intracapsular fracture neck of femur. Study design: Descriptive cross sectional study. Place and duration of study: Department of Orthopaedic Surgery & Traumatology, Peoples Medical University Hospital, Shaheed Benazir Abad from 1st December 2017 to 31st December 2020. Methodology: Sixty six cases of intracapsular femoral neck fractures with age ranging from 50 year to 75 year of either gender who were ambulatory before injury were included; while basicervical, younger than 50 years, with neuromuscular disorder, unfit for surgery, open fracture, bilateral injuries, osteoarthritis of hip, Rheumatoid, Gouty, pathological fractures, bedridden & who did not give consent for study, were excluded from the study. Functional outcome assessed by Harris hip score & data analyzed by SPSS version 23. Results: Twenty six (59.09%) were male and 40 (40.91%) were female with mean age of 64.3±7.77 year. Average time from injury to hospital arrival was 14.7±6.8 hours. Average time from hospitalization to surgery was 4.67±2.23 days. Average time of surgery was 55.67±9.9 minutes. Average hospital stay was 9.7±4.3 days. The average time of follow-up was 18.45±7.63 months. Conclusion: Bipolar implant is safe, effective, reliable, stable and cost effective implant for intracpsular fracture of femoral neck in elderly populace. The 66.66% of patients have satisfactory Harris hip score in follow up duration of 18.45±7.63 months. Keywords: Functional, Outcome, Femoral neck fractures, FNF, Bipolar, Hemiarthroplasty, HHS

Online Monitoring of Functional Electrical Properties in Aerosol Jet Printing Additive Manufacturing Process Using Shape-From-Shading Image Analysis

2017 ◽  
Vol 139 (10) ◽  
Author(s):  
Roozbeh (Ross) Salary ◽  
Jack P. Lombardi ◽  
Prahalad K. Rao ◽  
Mark D. Poliks
Keyword(s):  
Cross Section ◽  
Electrical Resistance ◽  
Online Monitoring ◽  
Shape From Shading ◽  
Sectional Area ◽  
Cross Sectional ◽  
Jet Printing ◽  
The Cross ◽  
Aerosol Jet Printing ◽  
Line Resistance

The goal of this research is online monitoring of functional electrical properties, e.g., resistance, of electronic devices made using aerosol jet printing (AJP) additive manufacturing (AM) process. In pursuit of this goal, the objective is to recover the cross-sectional profile of AJP-deposited electronic traces (called lines) through shape-from-shading (SfS) analysis of their online images. The aim is to use the SfS-derived cross-sectional profiles to predict the electrical resistance of the lines. An accurate characterization of the cross section is essential for monitoring the device resistance and other functional properties. For instance, as per Ohm’s law, the electrical resistance of a conductor is inversely proportional to its cross-sectional area (CSA). The central hypothesis is that the electrical resistance of an AJP-deposited line estimated online and in situ from its SfS-derived cross-sectional area is within 20% of its offline measurement. To test this hypothesis, silver nanoparticle lines were deposited using an Optomec AJ-300 printer at varying sheath gas flow rate (ShGFR) conditions. The four-point probes method, known as Kelvin sensing, was used to measure the resistance of the printed structures offline. Images of the lines were acquired online using a charge-coupled device (CCD) camera mounted coaxial to the deposition nozzle of the printer. To recover the cross-sectional profiles from the online images, three different SfS techniques were tested: Horn’s method, Pentland’s method, and Shah’s method. Optical profilometry was used to validate the SfS cross section estimates. Shah’s method was found to have the highest fidelity among the three SfS approaches tested. Line resistance was predicted as a function of ShGFR based on the SfS-estimates of line cross section using Shah’s method. The online SfS-derived line resistance was found to be within 20% of offline resistance measurements done using the Kelvin sensing technique.

Anthropometry-Based Surface Modeling of the Human Torso

1994 ◽  
Author(s):  
Peng Li ◽  
Peter R. M. Jones
Keyword(s):  
Human Body ◽  
Computer Aided Design ◽  
Three Dimensional ◽  
Human Growth ◽  
Surface Model ◽  
Cross Sectional ◽  
Practical Applications ◽  
Garment Design ◽  
Aided Design ◽  
Reference Body

Abstract There is an increasing need for computerized surface model of the human body in human growth, garment design and ergonomics. However, there is a shortage of three-dimensional (3-D) models of the human body in practical applications. This paper presents a new approach for constructing a 3-D surface model of the human torso using anthropometry. The torso is created by from a reference body of average shape which is represented by a family of cross-sectional curves. The shape and size of the reference body can be modified according to anthropometric data. This approach has been implemented on a personal computer. The resulting 3-D model is a parametric surface based on non-uniform B-splines and can easily be exported to other computer aided design applications.

Comparative Analysis of Preoperative and Postoperative Muscle Around Hip Joint by Computed Tomography Between Intertrochanteric Fracture and Femur Neck Fracture

2020 ◽  
Author(s):  
Sung Yoon Jung ◽  
Hyeon Jun Kim ◽  
Kyu Taek Oh
Keyword(s):  
Femoral Neck ◽  
Femoral Neck Fracture ◽  
Intertrochanteric Fracture ◽  
Femoral Neck Fractures ◽  
Final Visit ◽  
Cross Sectional ◽  
Fracture Group ◽  
Significant Difference ◽  
Neck Fracture

Abstract Background:This study assessed the changes in hip muscles by comparing the preoperative and postoperative CT scan results between patients with intertrochanteric versus femoral neck fractures. Methods:48 patients who received surgical treatment for intertrochanteric or femoral neck fractures from February 2013 to February 2019 and underwent pelvic computed tomography(CT) preoperative and postoperatively aged 65 and older with a minimum follow-up of 1 year were included. The subjects were divided into two groups: 26 patients with intertrochanteric fracture and 22 patients with femoral neck fracture. We measured the cross-sectional area(CSA) and attenuation of the gluteus medius(G.med), gluteus minimus(G.min), iliopsoas(IP), and rectus femoris(RF) on the contralateral side. Patient basic data were collected from medial records including sex, age, height, weight, BMI, BMD, Harris hip score (HHS), and length of follow-up until the final visit. Results: There was no significant difference in sex, age, height, weight, BMI, BMD, HHS, and length of follow-up until the final visit between two groups. The femoral neck fracture group had significantly larger CSA and cross-sectional area per weight(CSA/Wt) of the G.med and G.min(G.med CSA, CSA/wt preoperative 1995.29 vs 1713.64, 38.87 vs 32.74; postoperative 2144.98 vs 1815.56, 37.48 vs 32.78/G.min preoperative 745.22 vs 566.59, 14.32 vs 10.96; postoperative 764.39 vs 619.17, 14.78 vs 11.25). On the contrary, the intertrochanteric fracture group had significantly greater CSA and CSA/Wt of the IP and RF(IP preoperative 810.86 vs 661.88, 17.73 vs 9.42; postoperative 681.98 vs 571.32, 12.68 vs 9.88/RF preoperative 503.66 vs 386.72, 9.42 vs 7.23; postoperative 426.24 vs 349.31, 7.17 vs 5.23). HHS related with function had no significant correlation with postoperative CSA and CSA/Wt. There was no significant difference in attenuation between two groups. All subjects had a significant decrease of muscle attenuation postoperatively.Conclusions: The CSA of the hip abductor(G.med and G.min) was significantly larger in the femoral neck fracture group, while the CSA of the hip flexor(IP and RF) was significantly higher in the intertrochanteric fracture group. Based on these findings, choosing the rehabilitation program suitable for the fracture site is expected to be beneficial in hip fracture rehabilitation.

scholarly journals Optimization of Geometric Parameters of Thermal Insulation of Pre-Insulated Double Pipes

Energies ◽  
2019 ◽  
Vol 12 (6) ◽  
pp. 1012 ◽  
Author(s):  
Dorota Krawczyk ◽  
Tomasz Teleszewski
Keyword(s):  
Heat Flux ◽  
Heat Conduction ◽  
Cross Section ◽  
Thermal Insulation ◽  
Major Axis ◽  
Heat Losses ◽  
Sectional Area ◽  
Cross Sectional ◽  
Elliptical Shape ◽  
Half Axis

This paper presents the analysis of the heat conduction of pre-insulated double ducts and the optimization of the shape of thermal insulation by applying an elliptical shape. The shape of the cross-section of the thermal insulation is significantly affected by the thermal efficiency of double pre-insulated networks. The thickness of the insulation from the external side of the supply and return pipes affects the heat losses of the double pre-insulated pipes, while the distance between the supply and return pipes influences the heat flux exchanged between these ducts. An assumed elliptical shape with a ratio of the major axis to the minor half axis of an ellipse equaling 1.93 was compared to thermal circular insulation with the same cross-sectional area. All calculations were made using the boundary element method (BEM) using a proprietary computer program written in Fortran as part of the VIPSKILLS project.

Calculation of section modulus and moments of inertia of the 60E1 rail profile due to its head cross-section change

2019 ◽  
Vol 124 ◽  
pp. 99-114
Author(s):  
Jacek Makowski ◽  
Łukasz Stolarczyk ◽  
Paweł Muzolf
Keyword(s):  
Computer Aided Design ◽  
Basic Element ◽  
Railway Track ◽  
Lateral Direction ◽  
Cross Sectional ◽  
Moments Of Inertia ◽  
Section Modulus ◽  
Rail Vehicles ◽  
The Moment ◽  
Aided Design

The paper presents the theoretical foundations regarding the operational wear of rail heads. Rail, which constitute the basic element of the railway track, among others, guides the wheel in a lateral direction as well as enables a safe operation of rail vehicles. The criteria for the interaction of vehicles with the railway surface are described and the issues of interaction of the rail vehicle wheel with the rail is described. In the further part of the work an analysis of the influence of rail head wear of the 60E1 rail profile on the value of the moment of inertia Ix and sectional modulus Wx of this profile was carried out. The analysis was conducted on real, previously prepared samples of 60E1 operated rails. The methodology for calculating the geometric characteristics of cross-sectional characteristics of worn rails has been proposed using the Autodesk Autocad (Computer Aided Design software). The obtained values of moments of inertia and sectional modulus were compared with theoretical formulas described in the literature.

Modelling the Acoustical and Airflow Performance of Simple Lined Ventilation Apertures

2005 ◽  
Vol 12 (4) ◽  
pp. 277-292 ◽  
Author(s):  
D J Oldham ◽  
Jian Kang ◽  
M W Brocklesby
Keyword(s):  
Aspect Ratio ◽  
Cross Section ◽  
High Aspect Ratio ◽  
Natural Ventilation ◽  
Ventilation System ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Ventilation Performance ◽  
Acoustic Treatment

The pressure differences that can be used to drive a natural ventilation system are very small and thus large apertures are required to allow sufficient air to enter and leave a building to ensure good air quality or thermal comfort. Large apertures are potential acoustic weak points on a façade and may require some form of acoustic treatment such as absorbent linings, in which case the ventilator is similar to a short section of lined duct. In ducts, the performance of absorbent linings increases with the length of lining and the ratio of the length of lined perimeter to the cross sectional area of the duct. Thus, for a duct of a given cross sectional area, a lining is more effective for a duct with a high aspect ratio than for a duct with a square cross section. However, the high aspect ratio cross section will result in greater flow resistance and impede the airflow performance. In this paper numerical methods are employed to investigate the effect of different configurations of a lined aperture on the acoustical and ventilation performance of the aperture in order to establish the optimum configurations.

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