Gait Prediction Using Concurrent Musculoskeletal Control and FE Simulations

Author(s):  
Jason P. Halloran ◽  
Marko Ackermann ◽  
Ahmet Erdemir ◽  
Antonie J. van den Bogert

Current computational methods of simulating activities of daily living (ADL) have primarily consisted of musculoskeletal simulations [1]. Due to computational expense, simulations generally include assumptions which simplify joint or soft-tissue behavior. Joints are modeled as hinge or spherical and soft-tissue effects are included as spring-dashpot systems. Incorporating detailed deformable soft-tissue models would help overcome simplifying assumptions by coupling the behavior of a muscle loaded model with the underlying structures. Important clinical applications for a multi-domain simulation framework include, but are hardly limited to, predicting modifications to ADL to compensate for osteoarthritic pain or minimizing peak plantar pressures, which are believed to be significant for diabetic foot ulceration.

Author(s):  
Mohammed Mousa Bakri ◽  
Sung Ho Lee ◽  
Jong Ho Lee

Abstract Background A compact passive oxide layer can grow on tantalum (Ta). It has been reported that this oxide layer can facilitate bone ingrowth in vivo though the development of bone-like apatite, which promotes hard and soft tissue adhesion. Thus, Ta surface treatment on facial implant materials may improve the tissue response, which could result in less fibrotic encapsulation and make the implant more stable on the bone surface. The purposes of this study were to verify whether surface treatment of facial implant materials using Ta can improve the biohistobiological response and to determine the possibility of potential clinical applications. Methods Two different and commonly used implant materials, silicone and expanded polytetrafluoroethylene (ePTFE), were treated via Ta ion implantation using a Ta sputtering gun. Ta-treated samples were compared with untreated samples using in vitro and in vivo evaluations. Osteoblast (MG-63) and fibroblast (NIH3T3) cell viability with the Ta-treated implant material was assessed, and the tissue response was observed by placing the implants over the rat calvarium (n = 48) for two different lengths of time. Foreign body and inflammatory reactions were observed, and soft tissue thickness between the calvarium and the implant as well as the bone response was measured. Results The treatment of facial implant materials using Ta showed a tendency toward increased fibroblast and osteoblast viability, although this result was not statistically significant. During the in vivo study, both Ta-treated and untreated implants showed similar foreign body reactions. However, the Ta-treated implant materials (silicone and ePTFE) showed a tendency toward better histological features: lower soft tissue thickness between the implant and the underlying calvarium as well as an increase in new bone activity. Conclusion Ta surface treatment using ion implantation on silicone and ePTFE facial implant materials showed the possibility of reducing soft tissue intervention between the calvarium and the implant to make the implant more stable on the bone surface. Although no statistically significant improvement was observed, Ta treatment revealed a tendency toward an improved biohistological response of silicone and ePTFE facial implants. Conclusively, tantalum treatment is beneficial and has the potential for clinical applications.


2018 ◽  
Vol 2018 ◽  
pp. 1-3
Author(s):  
Alexandra W. Dretler ◽  
Jesse T. Jacob ◽  
Nadine G. Rouphael

A 74-year-old man presented to the emergency department with severe right leg cellulitis following a trip to the Bahamas where he swam in both chlorinated pools and the ocean. His blood cultures grew Shewanella species, a marine pathogen known to cause disease in humans, following exposure to seawater. He was treated with cefepime for a total of two weeks without needing any surgical intervention. The patient had complete resolution of infection and was able to return to his activities of daily living.


1993 ◽  
Vol 39 (1) ◽  
pp. 113-118 ◽  
Author(s):  
A. M. Jennings ◽  
A. Robinson ◽  
R. H. Kandler ◽  
R. P. Betts ◽  
R. E. J. Ryder ◽  
...  

2017 ◽  
Author(s):  
Zbigniew Starosolski ◽  
David S. Ezon ◽  
Rajesh Krishnamurthy ◽  
Nicholas Dodd ◽  
Jeffrey Heinle ◽  
...  

Author(s):  
Shilpa Jaryal ◽  
Jageer Chhina ◽  
Gurpreet Kaur ◽  
Shilpa Jaryal

Lasers are used in implant and periodontal field practices. Laser has various periodontal applications including calculus removal, decontamination of root and implant surfaces and bio stimulation, incision and ablation, osseous surgery, excision of the soft tissue, and bacterial reduction. There is a strong evidence that laser is used for surgical and nonsurgical periodontal therapies including root bio modification, bacterial decline and decontamination of infected implant surface, and removal of the pocket epithelium.Waterlase® and Periowave™ systems are recent devices that have further revolutionized the laser technology for its favorable clinical applications; however, the procedural cost with the laser device constitutes an obstacle for its routine application. Keywords: laser, biomodulation, fluorencence, LANAP


Author(s):  
Xiaodong Zhao ◽  
Baoxiang Shan ◽  
Assimina A. Pelegri

An integrated system is built to model and simulate the dynamic response of soft tissues. The mathematical formulation employs finite element and model order reduction approaches to develop a state space model for soft tissues that allows for time-efficient numerical analysis. The stimulus device and signal processing routines are built in Matlab/Simulink and then integrated with the finite element state space model. This integrated system facilitates expeditious numerical evaluation of different soft tissue models subjected to dynamic excitation. It further elucidates the effect of different stimulus sources, as well as relative influences of different sources of uncertainty.


2017 ◽  
Vol 17 (07) ◽  
pp. 1740016
Author(s):  
MONAN WANG ◽  
ZHIYONG MAO ◽  
XIANJUN AN

This study used biomechanical models of soft tissues based on combined exponential and polynomial models. Finite element methods were used to solve material nonlinear and geometrically nonlinear problems of soft tissue models. This involved assigning a screening coefficient in the model-accelerated computing process to filter the units involved in the calculation. The screening coefficient controlled both the accuracy of the results of simulation and the computing speed through setting up a subset of finite elements. The fast computer method based on the screening coefficient was applied to the rectus femoris simulation.


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