Behavior of Bridge Outrigger Knee Joint Systems

1995 ◽  
Vol 11 (3) ◽  
pp. 477-509 ◽  
Author(s):  
Christopher R. Thewalt ◽  
Božidar Stojadinović

The catastrophic collapse of the Cypress Street Viaduct during the 1989 Loma Prieta earthquake emphasized the vulnerability of older elevated freeway bridge structures. One part of a joint Caltrans/University of California at Berkeley research project is the investigation of outrigger knee joints found in elevated freeway bents. This project has two principal goals: to evaluate the behavior of the existing outrigger knee joint systems under a combined transverse and longitudinal loading, and to design and experimentally verify upgrading strategies and repair techniques suitable for application on the existing elevated freeways. The primary focus of this paper will be to present the behavior of the as-built and upgraded systems, but an overview of the design method and the analytical tools used in the upgrade will also be presented.

Author(s):  
Mallikarjunaswamy Shivagangadharaiah Matada ◽  
Mallikarjun Sayabanna Holi ◽  
Rajesh Raman ◽  
Sujana Theja Jayaramu Suvarna

Background: Osteoarthritis (OA) is a degenerative disease of joint cartilage affecting the elderly people around the world. Visualization and quantification of cartilage is very much essential for the assessment of OA and rehabilitation of the affected people. Magnetic Resonance Imaging (MRI) is the most widely used imaging modality in the treatment of knee joint diseases. But there are many challenges in proper visualization and quantification of articular cartilage using MRI. Volume rendering and 3D visualization can provide an overview of anatomy and disease condition of knee joint. In this work, cartilage is segmented from knee joint MRI, visualized in 3D using Volume of Interest (VOI) approach. Methods: Visualization of cartilage helps in the assessment of cartilage degradation in diseased knee joints. Cartilage thickness and volume were quantified using image processing techniques in OA affected knee joints. Statistical analysis is carried out on processed data set consisting of 110 of knee joints which include male (56) and female (54) of normal (22) and different stages of OA (88). The differences in thickness and volume of cartilage were observed in cartilage in groups based on age, gender and BMI in normal and progressive OA knee joints. Results: The results show that size and volume of cartilage are found to be significantly low in OA as compared to normal knee joints. The cartilage thickness and volume is significantly low for people with age 50 years and above and Body Mass Index (BMI) equal and greater than 25. Cartilage volume correlates with the progression of the disease and can be used for the evaluation of the response to therapies. Conclusion: The developed methods can be used as helping tool in the assessment of cartilage degradation in OA affected knee joint patients and treatment planning.


Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1825
Author(s):  
Caiyang Wei ◽  
Theo Hofman ◽  
Esin Ilhan Caarls

For an electric vehicle (EV) with a continuously variable transmission (CVT), a novel convex programming (CP)-based co-design method is proposed to minimize the total-cost-of-ownership (TCO). The integration of the electric machine (EM) and the CVT is the primary focus. The optimized system with co-design reduces the TCO by around 5.9% compared to a non-optimized CVT-based EV (based on off-the-shelf components) and by around 2% compared to the EV equipped with a single-speed transmission (SST). By taking advantage of the control and design freedom provided by the CVT, the optimal CVT, EM and battery sizes are found to reduce the system cost. It simultaneously finds the optimal CVT speed ratio and air-flow rate of the cooling system reducing the energy consumption. The strength of co-design is highlighted by comparing to a sequential design, and insights into the design of a low-power EV that is energy-efficient and cost-effective for urban driving are provided. A highly integrated EM-CVT system, which is efficient, low-cost and lightweight, can be expected for future EV applications.


1996 ◽  
Vol 76 (6) ◽  
pp. 3740-3749 ◽  
Author(s):  
V. Neugebauer ◽  
H. Vanegas ◽  
J. Nebe ◽  
P. Rumenapp ◽  
H. G. Schaible

1. The present study addresses the involvement of voltage-dependent calcium channels of the N and L type in the spinal processing of innocuous and noxious input from the knee joint, both under normal conditions and under inflammatory conditions in which spinal cord neurons become hyperexcitable. In 30 anesthetized rats, extracellular recordings were performed from single dorsal horn neurons in segments 1–4 of the lumbar spinal cord. All neurons had receptive fields in the ipsilateral knee joint. In 22 rats, an inflammation was induced in the ipsilateral knee joint by kaolin and carrageenan 4–16 h before the recordings. The antagonist at N-type calcium channels, omega-conotoxin GVIA (omega-CTx GVIA), was administered topically in solution to the dorsal surface of the spinal cord at the appropriate spinal segments in 6 rats with normal joints and in 12 rats with inflamed knee joints. The antagonist at L-type channels, nimodipine, was administered topically in 5 rats with normal joints and in 11 rats with inflamed knee joints. In another five rats with inflamed joints, antagonists at L-type calcium channels (diltiazem and nimodipine) and omega-CTx GVIA were administered ionophoretically with multibarrel electrodes close to the neurons recorded. 2. The topical administration of omega-CTx GVIA to the spinal cord reduced the responses to both innocuous and noxious pressure applied to the knee joint in a sample of 11 neurons with input from the normal joint and in a sample of 16 neurons with input from the inflamed joint (hyperexcitable neurons). The responses were decreased to approximately 65% of the predrug values within administration times of 30 min. A similar reduction of the responses to innocuous and noxious pressure was observed when omega-CTx GVIA was administered ionophoretically to nine hyperexcitable neurons. In neurons with input from the normal or the inflamed knee joint, the administration of omega-CTx GVIA led also to a reduction of the responses to innocuous and noxious pressure applied to the noninflamed ankle joint. 3. The topical administration of nimodipine decreased the responses to innocuous and noxious pressure applied to the knee in a sample of 9 neurons with input from the normal joint and in a sample of 16 neurons with input from the inflamed knee joint (hyperexcitable neurons). Within administration times of 30 min, the responses were reduced to approximately 70% of the predrug values. In hyperexcitable neurons, the responses to innocuous and noxious pressure applied to the knee were also decreased during ionophoretic administration of nimodipine (6 neurons) and diltiazem (9 neurons). When the noninflamed ankle was stimulated, the responses to innocuous pressure were reduced neither in neurons with input from the normal knee nor in neurons with input from the inflamed knee, but the responses of hyperexcitable neurons to noxious pressure onto the ankle were reduced. The ionophoretic administration of the agonist at the L-type calcium channel, S(-)-Bay K 8644, enhanced the responses to mechanical stimulation of the knee joint in all 14 hyperexcitable neurons tested. The effect of S(-)-Bay K 8644 was counteracted by both diltiazem (in 6 of 6 neurons) and nimodipine (in 5 of 5 neurons). 4. These data show that antagonists at both the N- and the L-type voltage-dependent calcium channels influence the spinal processing of input from the knee joint. The data suggest, therefore, that voltage-dependent calcium calcium channels of both the N and the L type are important for the sensory functions of the spinal cord. They are involved in the spinal processing of nonnociceptive as well as nociceptive mechanosensory input from the joint, both under normal and inflammatory conditions. The present results show in particular that N- and L-type channels are likely to be involved in the generation of pain evoked by noxious mechanical stimulation in normal tissue as well as in the mechanical hyperalgesia that is usually pres


2018 ◽  
Vol 5 ◽  
pp. 3-11
Author(s):  
Angela Basanets ◽  
Maria Bulavko

The paper analyzes the effectiveness of magnetic resonance imaging with cartilage diagram in diagnosing signs of professional deforming arthrosis of knee joints in miners working in conditions of significant physical loading. Aim of the research – to determine of diagnostic efficiency of indicators of magnetic resonance imaging of the knee joint and cartilage diagram in miners of the main occupations suffering from deforming arthrosis. Methods. The research is conducted in 30 miners of basic occupations: 20 mining workers of breakage face (MWBF) and 10 machinists of shearer mining machines (МSMM) have been treated in the inpatient department of occupational pathology of the Lviv Regional Clinical Hospital in 2015-2017 due to deforming arthrosis. Damages of the main anatomical elements of the knee joint with arthrosis were analyzed, visualized initially with the help of MRI, and then - cartilage diagram. Results. According to the MRI data, in miners of the main occupations with arthrosis of the knee joint the posterior cross-shaped ligament are most commonly affected (in 75.0±9.7 % MWBF and 70.0±14.5 % МSMM), damage to the medial collateral ligament are diagnosed less frequently (in 5.0±4.9 % in the MWBF and in 10.0±9.5 % in the МSMM). On average 3.8±0.4 modified elements of the knee joint are visualized in patients, whereas 4.8±0.1 affected areas are visualized on the cartilage diagram (р<0.05). In 86.7±6.2 % patients, in the analysis of cartilage diagram, changes in all five analyzed areas are diagnosed, indicating a higher efficiency of the diagnosis of changes in the structures of the joint with DA of the professional etiology of the method of cartilage diagram compared with MRI. According to the cartilage diagram the most significant changes are noted in the hypertrophy of the femur: among all miners 62.5±0.3 ms (medial) and 62.6±0.4 ms (lateral), in the MWBF group the average time of Т2-delay is the largest in the area of the medial hypertrophy of the femur is 60.9±2.3 ms, in the МSMM group – in the area of the lateral hypertrophy of the femur: 66.7±3.3 ms, which can be linked to the peculiarities of the forced working position of miners of these professions and the kinetics of joint structures. These results can be used to diagnose the initial lesions of joint structures with DA of professional genesis, as well as the creation of prognostic models for determining the the degree of risk of development of knee joint damage, which will allow to improve the system of personified approach to diagnostic and preventive measures in working persons in conditions of considerable physical activity and forced working position.


Author(s):  
Islamova K. A . ◽  
◽  
Khasanov F. Sh ◽  
Toirov E. S. ◽  
◽  
...  

The purpose of this study was to investigate the function of knee joints in patients with early osteoarthritis (OA, according to the criteria of the American rheumatology Association 2010) stage I-III using visual analogue scale (VAS) for pain intensity and treatment outcomes, Lequesne index, expert indicators, samples of 4 meter walk to assess the effectiveness of intra-articular injection Hyaluronic Chondro. 80 patients aged 28 to 55 years were examined. The treatment regimen included recommendations from the European rheumatology League (EULAR, 2016) and Russia (Nasonov E. L., 2017). The results of therapy were evaluated in two groups. The first group included 43 patients who received Hyaluronic Chondro in the form of intra-articular injections, the second-37 patients who received chondroprotectors inside or in the form of intramuscular injections. Conclusion. Intra-articular administration of the drug Chondrogard has a positive clinical effect in early stage II-III OA with moderate impairment of knee joint function. The course of treatment should last at least 2 months


2021 ◽  
pp. 6-14
Author(s):  
О. О. Bespalova ◽  
P. F. Rybalko ◽  
A. M. Sitovskyi ◽  
T. Y. Tsjupak ◽  
I. V. Savchuk

Excessive training loads during sports cause chronic functional overload of the joints and their trauma, which reduces the quality of life of athletes, limits activity and participation, termination of sports careers, and in severe cases - disability. In sports practice, one of the most common sites of osteoarthritis is the knee joints (gonarthrosis). Gonarthrosis of the knee joint is a degenerative-dystrophic disease in which the destruction of hyaline cartilage, deformation of bone tissue and the qualitative composition of synovial fluid. A key link in the development of an individual program of rehabilitation intervention is the formulation of a rehabilitation diagnosis. The aim of the research: to determine the rehabilitation diagnosis of patients with gonarthrosis of the knee joints on the basis of the International Classification of Functioning, Restriction of Life and Health (ICF). Materials and methods: theoretical (analysis and generalization of scientific-methodical and clinical literature); clinical (analysis of medical records, communication, palpation, clinical and functional testing; physical examination); scale methods for assessing the condition of patients (Leken index, pain scale, depression scale (CES-D), assessment of quality of life according to the SF-36 questionnaire); instrumental (goniometry, manual-muscular testing). The research involved 7 veteran athletes aged 45 to 49 years with primary gonarthrosis stage II. Inclusion criteria: current athletes - men of different specializations; primary gonarthrosis of the second radiological stage according to Kellgren; duration of pain not less than 4 months; the level of pain when walking on the scale of YOUR 45 and more; age of patients older than 45 years; informational consent of patients to participate in the research. Inclusion criteria: secondary gonarthrosis of the knee joint; the presence of comorbidities; severe condition of the patient; knee surgery; planning of arthroplasty of the knee joint; intra-articular injections; lack of information consent. Rehabilitation diagnosis is the most complete reflection of the patient's current problems, which affect the level of his functioning, activity and participation, and are significant for him. It is established by all members of the multidisciplinary team, and is based on the results of comprehensive rehabilitation diagnostics. The main tool for establishing a rehabilitation diagnosis are the categories and domains of IFF. Rehabilitation diagnosis of patients with gonarthrosis: moderate structural changes in the knee joints (s750.2), episodic moderate pain (b28014.2), short-term morning stiffness (b7800.2), decreased mobility of the knee joint (b710.2), his stability (b7150.2) and support function, decrease in muscle tone (b7350.2) and strength of the quadriceps femoris (b7300.2), which limits domestic activity and prolongs it over time (d450.1); difficulties in changing body position (d410.2), moving up stairs and moving long distances (d460.3), which limits participation in active forms of recreation. Patients report poor mood, depression due to health and forced restriction of participation (b152. 1), and concerns about future careers. Conclusions. Rehabilitation care is provided to patients in several stages, one of which is the formulation of a rehabilitation diagnosis. Rehabilitation diagnosis was established, in which the current problems of patients at the level of structure and function, activity and participation, as well as contextual factors that contribute, limit or prevent the achievement of the desired level of functional independence, allow individualization of rehabilitation intervention to bring this level to the maximum possible.


Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6495
Author(s):  
Bartłomiej Sawaryn ◽  
Natalia Piaseczna ◽  
Szymon Sieciński ◽  
Rafał Doniec ◽  
Konrad Duraj ◽  
...  

The knee joint, being the largest joint in the human body, is responsible for a great percentage of leg movements. The diagnosis of the state of knee joints is usually based on X-ray scan, ultrasound imaging, computerized tomography (CT), magnetic resonance imaging (MRI), or arthroscopy. In this study, we aimed to create an inexpensive, portable device for recording the sound produced by the knee joint, and a dedicated application for its analysis. During the study, we examined fourteen volunteers of different ages, including those who had a knee injury. The device effectively enables the recording of the sounds produced by the knee joint, and the spectral analysis used in the application proved its reliability in evaluating the knee joint condition.


2019 ◽  
Vol 9 (18) ◽  
pp. 3713 ◽  
Author(s):  
Yanming Fu ◽  
Xin Wang ◽  
Tianbiao Yu

The risk of knee injuries in freestyle skiing athletes that perform aerials is high. The internal stresses in the knee joints of these athletes cannot easily be directly measured. In order to ascertain the mechanical response of knee joints during the landing phase, and to explore the mechanism of damage to the cartilage and ligaments, a finite element model of the knee joint was established. Three successful landing conditions (neutral, backward, or forward landing) from a triple kicker were analyzed. The results demonstrate that the risk of cruciate ligament damage during a neutral landing was lowest. A forward landing carried medium risk, while backward landing was of highest risk. Backward and forward landing carried risk of injury to the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL), respectively. The magnitude of stress on the meniscus and cartilage varied for all three landing scenarios. Stress was largest during neutral landing and least in backward landing, while forward landing resulted in a medium level of stress. The results also provide the basis for training that is scientifically robust so as to reduce the risk of injury and assist in the development of a professional knee joint protector.


2016 ◽  
Vol 842 ◽  
pp. 435-444 ◽  
Author(s):  
Emilio O. Bachtiar ◽  
Tatacipta Dirgantara ◽  
Sandro Mihradi ◽  
Andi Isra Mahyuddin

An invalid is a person with physical or mental abnormalities which hinders their ability of doing normal human activities. One of the aforementioned abnormalities is the loss or malfunction of a body part or organ, such as the human leg. Problems brought about by this disability could be alleviated by the use of prosthetic limbs to restore normal bodily functions [1]. While there are many needs for leg prosthetics in Indonesia, the price of commercially available prosthetic is prohibitively high for most amputees. The current available affordable prosthetics are very basic and employ monocentric knee joints. Here an attempt is made towards acquiring an optimal design of an affordable prosthetic leg using previously developed four-bar knee joint [2,3]. The design is carried out by implementing a systematic design method to arrive at an affordable, yet ones with better performances. The procedure involves a rubric and analyzing various alternatives to arrive at an optimal design conclusion. The evaluation objective is to maximize the performance of the leg and knee prosthetics through an extensive analysis with considerations from various stakeholders, including the potential users, fabricator, and hospitals in Indonesia [4]. The final design of the leg consists of a composite socket, an aluminum pylon, and a solid-ankle cushioned-heel foot design. Its components are modular and compatible with prosthetic industry standards. The knee is made of a combination of polymers and stainless steel and employs a polycentric mechanism in order to satisfy design requirements while keeping costs low [4,5]. The leg and knee were then fabricated according to the analysis results. The total cost of fabrication is approximately 5.5 million IDR, significantly cheaper than commercial prosthetics. The prototype is then tested and examined using a gait analysis system previously developed at Institut Teknologi Bandung by the Biomechanics Research Team [6]. The results show satisfactory performance, albeit with a host of potential improvements.


Author(s):  
Jaw-Lin Wang ◽  
Cheng-Hsien Chung ◽  
Chung-Kai Chiang

Degenerative osteoarthritis is recognized as the consequences of mechanical injuries. The abnormal impact force applied to articular cartilage would result in bone fracture or surface fissuring, and would cause the osteoarthritis [1,2]. The relation among the injury and impact energy was well studied. However, how the external energy attenuated to the internal joint is not carefully studied yet. The porcine knee joint was used as a biomechanical model for the simulation of human knee joint during impact loading. The objective of current study was to find the variation of kinetic characteristics between human and porcine knee joint during axial impact loading. Eight fresh-frozen knee joints from 10 month-old swine and seven cadaver human knee joints were used in the experiment. The mechanical responses such as forces and bending moment of knee joint, and the accelerations of femur was quantitatively analyzed. The results showed that the axial force response between human and porcine joints was similar, however, the anteroposterior shear, flexion bening moment and accelerations of these two joints were different.


Sign in / Sign up

Export Citation Format

Share Document