Development of a New Artificial Knee Joint for an Asian and Middle Eastern Population

Author(s):  
Harcharan Singh Ranu

Design of an artificial knee was developed using computer 3-D modeling, the high flexion knee was obtained by using a multi-radii design pattern, The increase of final 20 degrees in flexion was obtained by increasing the condylar radii of curvature. The model of the high flexion knee was developed and one of the models was subjected to finite element modeling and analysis. The compositions of components in the artificial knee were, femoral component and the tibial component were metal, whereas the patellar component and the meniscal insert were made using polyethylene. The metal component used for the analysis in this study was Ti6Al4V and the polyethylene used was UHMWPE. Overall biomaterials chosen were: meniscus (UHMWPE, mass = 0.0183701 kg, volume = 1.97518e-005 m3), tibial component (Ti6Al4V, mass = 0.0584655 kg, volume = 1.32013e-005 m3), femoral component (Ti6Al4V, mass = 0.153122 kg, volume = 3.45742e-005 m3), total artificial assembly (mass = 0.229958 kg, volume = 6.75e-005m3). However, in this design the load had been taken to 10 times the body weight. The weight over single knee is only half the maximum load as the load is shared between the two knee joints. Following were the loading conditions, taking average body weight to be 70Kgs and taking extreme loading conditions of up to 10 times the body weight, i.e. 700Kgs on each of the leg performed the Finite Element Analysis (FEA) over the newly designed knee. The loading was done at an increment of 100 Kgs. The loading conditions and the meshing details for the analysis of the assembly were Jacobian check: 4 points, element size: 0.40735 cm, tolerance: 0.20367 cm, quality: high, number of elements: 80909, number of nodes: 126898. A maximum load of 600 Kgs is optimum for this model. The other components observed linear elastic behavior for the applied loads. Based on these results it was determined that the load bearing capacity of the model were well within the failure levels of the materials used for the analysis. A maximum load of 600 Kgs is optimum for this model. The other components observed linear elastic behavior for the applied loads. Based on these results it was determined that the load bearing capacity of the model were well within the failure levels of the materials used for the analysis. Conclusion drawn from this is that for the first time an innovative new design of an artificial knee joint to suite a segment of some religious population has been developed. This allows them to pray, bend in different positions and squat without too much difficulty.

Metals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 397
Author(s):  
Yahya Ali Fageehi

This paper presents computational modeling of a crack growth path under mixed-mode loadings in linear elastic materials and investigates the influence of a hole on both fatigue crack propagation and fatigue life when subjected to constant amplitude loading conditions. Though the crack propagation is inevitable, the simulation specified the crack propagation path such that the critical structure domain was not exceeded. ANSYS Mechanical APDL 19.2 was introduced with the aid of a new feature in ANSYS: Smart Crack growth technology. It predicts the propagation direction and subsequent fatigue life for structural components using the extended finite element method (XFEM). The Paris law model was used to evaluate the mixed-mode fatigue life for both a modified four-point bending beam and a cracked plate with three holes under the linear elastic fracture mechanics (LEFM) assumption. Precise estimates of the stress intensity factors (SIFs), the trajectory of crack growth, and the fatigue life by an incremental crack propagation analysis were recorded. The findings of this analysis are confirmed in published works in terms of crack propagation trajectories under mixed-mode loading conditions.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1038-1038
Author(s):  
Michael Miklus ◽  
Pedro Prieto ◽  
Cynthia Barber ◽  
Robert Rhoads ◽  
Samer El-Kadi

Abstract Objectives The objectives of this study were to determine the effect of 2’fucosyllactose (2’FL) and fat blends on growth, body composition and fatty acid profile of the liver and brain using the neonatal pig as a model for the human infant. Methods Pigs (3 d old) were randomly assigned to either: 1. control, 2. Palm Olein (PO) fat blend – Low 2'-FL, 3. PO – High 2'-FL, 4. High oleic acid (HO) – Low 2'-FL, 5. HO FB – High 2'-FL, 6. PO FB – GLA, or 7. kept with their sows. Pigs in groups 1 to 6 received 250 ml·kg−1·d−1 of formula in 5 equal meals for 15 d. On day 14 of the study, groups 1–6 received intraperitoneal E. coli LPS challenge at 100 µg·kg−1 weight. Results Body weight was greater for piglets fed by sows than those in the other groups (P < 0.001). In addition, % fat and bone mineral content were higher in the sow-fed group while lean % was less sow-fed piglets (group 7) compared with those in the other groups (P < 0.05). Only longissimus weight expressed as a % of body weight, was greater for group 7 compared with all other groups (P < 0.001). Soleus, semitendinosus, brain, heart and spleen weights as a % of body weight were similar across all groups. However, liver weight as a % of body weight was greater in groups 1–6 (3.7%) compared with group 7 (2.8%; P < 0.001). The proportion of brain 16:1 fatty acid was less (0.83%) for groups 1–6 than for group 7 pigs (1.08%; P < 0.0001). The proportion of 20:3 N6 was greatest (0.66%) for group 3 compared with groups 1 and 4 (0.55%; P < 0.05). In addition, the proportion of 20:5 N3 was greatest (0.12%) for group 3 compared with groups 1 and 7 (0.07%; P < 0.05). The proportion of liver 16:1, 18:0, and 18:1 cis-11 fatty acids were greater for group 7 (2.3, 23, 2.2%) than groups 1–6 (0.2, 20, 1.2%; P < 0.0001). Conversely, the contribution of 14:0, 18:1 cis-9, 18:3 N6 cis-6,9,12, and 22:6 N3 were greater for pigs in groups 1–6 (1.3, 0.6, and 14, 7.8%) compared with those in group 7 (0.5, 8.5, 0.2 and 3.5%; P < 0.0001). Conclusions Our data suggest that feeding 2’fucosyllactose had no effect on the body weight gain and composition in neonatal pigs. Our data also suggest that dietary fatty acids have a greater effect on liver than on brain fatty acid composition. Funding Sources Funding for the work was provided by Perrigo Nutritionals, LLC.


2000 ◽  
Author(s):  
Chris L. Mullen ◽  
Prabin R. Tuladhar

Abstract Discussion of a Performance - Based Engineering evaluation procedure for an existing interstate highway bridge in north Mississippi. The bridge is in a highly trafficked location near the Memphis Metropolitan area and is reflective of modern design practices in Mississippi. Results are presented of nonlinear damage response and displacement ductility performance of the reinforced concrete bents and their foundations predicted using static finite element (FE) computations. The model considers the composite action of the concrete and the reinforcing steel materials under axial force, shear, torsion and flexure. The performance-based evaluation includes three-dimensional computational simulations of the nonlinear bridge system, including substructures and superstructure. The response spectrum dynamic analysis method will also be carried out on the linear elastic three-dimensional model to predict the linear elastic behavior. Field vibration measurements, including ambient and hammer-impact, were performed to calibrate the models. The computed transfer functions are currently being evaluated to correlate vibration measurements and the Finite element models.


2007 ◽  
Vol 23 (1-2) ◽  
pp. 13-20
Author(s):  
Andrey Kurtenkov

It is related leg problems to the realization of the necessity of doing a detailed analysis of the phenotype correlations between body weight and exterior measurements. As a result of the study, lower coefficients have been obtained of the correlation between the girth of the tarso metatarsus on one hand, and the body weight and the girth behind the wings, on the other hand (respectively 0.563 and 0.608), compared with the one between the body weight and the girth behind the wings (0.898). It is advisable in the selection of ostriches to take into consideration the necessity of a higher phenotypic correlation between the girth of the tarso metatarsus on the one hand, and the body weight and the girth behind the wings on the other hand, with a view to preventing leg problems.


2020 ◽  
Vol 129 (4) ◽  
pp. 950-974 ◽  
Author(s):  
Cyril Etienne ◽  
Christophe Mallet ◽  
Raphaël Cornette ◽  
Alexandra Houssaye

Abstract Many tetrapod lineages show extreme increases in body mass in their evolutionary history, associated with important osteological changes. The ankle joint, essential for foot movement, is assumed to be particularly affected in this regard. We investigated the morphological adaptations of the astragalus and the calcaneus in Rhinocerotidae, and analysed them in light of a comparative analysis with other Perissodactyla. We performed 3D geometric morphometrics and correlated shape with centroid size of the bone and body mass of the species. Our results show that mass has an influence on bone shape in Rhinocerotidae and in Perissodactyla, but this is not as strong as expected. In heavy animals the astragalus has a flatter trochlea, orientated more proximally, associated with a more upright posture of the limb. The calcaneus is more robust, possibly to sustain the greater tension force exerted by the muscles during plantarflexion. Both bones show wider articular facets, providing greater cohesion and better dissipation of the loading forces. The body plan of the animals also has an influence. Short-legged Teleoceratina have a flatter astragalus than the other rhinocerotids. Paraceratherium has a thinner calcaneus than expected. This study clarifies adaptations to high body weight among Rhinocerotidae and calls for similar investigations in other groups with massive forms.


1974 ◽  
Vol 83 (1) ◽  
pp. 151-160 ◽  
Author(s):  
A. C. Field ◽  
A. R. Sykes ◽  
R. G. Gunn

SUMMARYExcretion of D.M., N, Ca, P and Mg in faeces, and N, P and Mg in urine were measured at intervals over 12 months in breeding Scottish Blackface sheep grazing hill pastures. These values were used with data on reproductive performance and body compositional changes, to calculate the energy, nitrogen and mineral balances. The sheep were: 11 6½-year-old with sound mouths (SM), 16 6½-year-old with broken mouths (BM), 16 5½-year-old with all permanent incisors clipped to gum level (CM) and 16 2½-year-old (Y). An energy supplement was given at the end of gestation and during early lactation. All faeces were collected and creatinine was used as an internal marker to estimate urine volume.Faecal D.M. output ranged from 443 to 662 g/day, with highest values in November and lowest in May. Average values for the BM sheep were lower than those for the other groups but when output was expressed as a power function of body weight, the values for the Y sheep were 15% higher than those for the other groups. Faecal excretions of Ca and P in January and February were very low and the values for P were half the expected endogenous faecal loss.Urinary output ofN ranged from 6·0 g/day in February to 22·2 g/day in August and the corresponding urinary urea N: total N ratios were 0·24 and 0·69. Urinary Mg output was highest in late summer and early winter but urinary P showed no consistent trends.The estimated daily intakes of DOM (g) were 936 in November 1969, 599 in January, 414 in February, 1075 in May, 1150 in August and 946 in November 1970.The loss of energy from the body between mating (November) and mid-lactation (June) ranged from 9·5 to 16·8% of the total calculated ME requirements in the Y and BM sheep, respectively. Maintenance requirements averaged 204 kJ/kg body weight/day and the value for the Y sheep was 12% higher than the mean for the older sheep.Nitrogen and mineral balances were calculated for February, May, August and November. The sheep were protein-deficient in winter, not from a shortage of crude protein in the diet but because of its low digestibility (34%). Intakes of Ca and P in winter were low and a real possibility of a P deficiency exists. Estimates of the concentrations of N and of minerals in the herbage consumed by the sheep were made and compared with those obtained for cut herbage from the same pastures. It would appear that the sheep selected herbage of a higher protein content than that of the cut herbage. Herbage selection was greatest in November.


2007 ◽  
Vol 567-568 ◽  
pp. 225-228 ◽  
Author(s):  
Luboš Náhlík ◽  
Lucie Šestáková ◽  
Pavel Hutař

The objective of the paper is to investigate the direction of a further crack propagation from the interface between two elastic materials. The angle of crack propagation changes when the crack passes the interface. The suggested procedure makes it possible to estimate an angle of propagation under which the crack will propagate into the second material. The assumptions of linear elastic fracture mechanics and elastic behavior of the body with interfaces are considered. The finite element method was used for numerical calculations. The results obtained might contribute to a better understanding of the failure of materials with interfaces (e.g. layered composites, materials with protective coatings) and to a more reliable estimation of the service life of such structures.


1961 ◽  
Vol 12 (1) ◽  
pp. 124 ◽  
Author(s):  
RH Watson ◽  
LC Gamble

Observations were made on the occurrence of mating and lambing in Merino ewes of three groups born in the spring, summer, and winter respectively. The lambs ware weaned at 13½–14½ weeks of age, and joined with rams within the following 2 weeks, some with fertile rams, others with vasectomized rams. Thereafter they ran with rams continuously or until lambing occurred. With few exceptions the first oestrus occurred between late November and May (summer and autumn), and the first conception between November and June. Of the ewes born in the spring, summer, and winter, 78, 100, and 95% respectively exhibited oestrus, and 63, 95, and 80% respectively conceived during the first spring, summer, and autumn following birth. All of the remainder experienced oestrus and all except one conceived during the same period in the following year. Both the age and the body weight of the ewes when oestrus and when conception first occurred varied widely. Both were least in the animals born in the spring and greatest in the animals born in the summer. The sexual season was shorter in the young ewes than it was in mature ewes. Further, the first sexual season of the youngest ewes at the time (those born in the spring) was only one-third of the length of the second sexual season or of the first sexual season of the ewes of the other two groups. There was little delay between the first opportunity to conceive and conception. However, among the ewes which mated youngest the proportion which lambed was lower than that in the other young ewes, which in turn was lower than in mature ewes. In addition, the gestation period in at least half of the ewes which lambed 3 youngest was substantially longer than it was in all except a very few of the other ewes


Author(s):  
M. Ibnelbachyr ◽  
I. Boujenane ◽  
A. Chikhi

SummaryThe Moroccan goat livestock is characterized by the existence of different phenotypes distributed among diverse geographic locations. The objective of this study was to analyse the morphometric traits that differentiate the Draa breed from the other local populations raised in areas close to its cradle zone. Eight morphometric measurements were taken on 287 goats in South-eastern and Southern Morocco. The variance analysis, fitting a model that included the random effect of animal and the fixed effects of population, gender and age of animal, was used. Mahalanobis distances were calculated between identified populations and an Unweighted Pairs Group Method Analysis tree was built. Draa goats had the highest height at withers (61.5 cm), heart girth (74.4 cm), body length (64.6 cm) and live body weight (27.2 kg). These morphometric traits varied significantly among populations as well as the age and the gender of animal. The most discriminating traits between the identified populations were the body length, the heart girth, the hair length, the horn length, the ear length and the live body weight. Draa animals had the largest genetic distances from the other populations and appeared more distinguished from them. This differentiation can contribute in defining the phenotypic standard of the breed and in orienting its genetic improvement programs in the future.


1982 ◽  
Vol 98 (2) ◽  
pp. 241-245 ◽  
Author(s):  
T. W. Searle ◽  
N. McC. Graham ◽  
J. B. Donnelly

SUMMARYCorriedale and Dorset Horn castrate male (wether) lambs reared at pasture were weaned at 19 kg live weight (LW), brought indoors and fed a high protein diet such that half of each group grew at ca. 200 g/day and the other half at ca. 100 g/day. Animals were slaughtered at 25 and 30 kg LW and chemical composition (protein, fat, energy, water and ash) of the body determined. The relationship between each body component and shorn empty-body weight was examined by regression analysis.Within levels of feeding the results were similar in the two breeds. When comparisons were made between feeding levels, the slower-growing animals contained more fat, energy and ash than the faster-growing group, less water, but similar amounts of protein at any given empty-body weight.


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