The cause of subchondral bone cysts in osteoarthrosisA finite element analysis

2004 ◽  
Vol 75 (5) ◽  
pp. 554-558 ◽  
Author(s):  
Hans Dürr ◽  
Heiner Martin ◽  
Christoph Pellengahr ◽  
Marcus Schlemmer ◽  
Markus Maier ◽  
...  
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Subchondral Bone ◽  
Bone Cysts ◽  
Element Analysis ◽  
Subchondral Bone Cysts

Impact of Size and Shape of Equine Femoral Subchondral Bone Cysts With a Transcondylar Screw on Predicted Bone Formation Area in a Finite Element Model

2020 ◽  
Vol 142 (6) ◽  
Author(s):  
Lance L. Frazer ◽  
Elizabeth M. Santschi ◽  
Scott J. Ring ◽  
Ross E. Hewitt ◽  
Kenneth J. Fischer
Keyword(s):  
Finite Element ◽  
Bone Formation ◽  
Subchondral Bone ◽  
Femoral Condyle ◽  
Element Model ◽  
Bone Cysts ◽  
Bone Apposition ◽  
Element Analysis ◽  
Subchondral Bone Cysts ◽  
Secondary Injuries

Abstract Equine subchondral bone cysts (SBCs) develop most often in the medial femoral condyle (MFC) of yearlings intended for performance. SBCs often cause lameness and can cause secondary injuries to the meniscus and tibial cartilage. A novel surgical technique using a transcondylar lag screw (TLS) across an MFC SBC has shown success in lameness resolution and radiographic healing of MFC SBC. In a previous study using finite element analysis, our lab showed that a TLS stimulated bone formation on the inner surface of the SBC and altered third principal stress vectors to change the direction of surface compression to align with the screw axis. This work extended the previous study, which was limited by the use of only one idealized SBC. Our objective was to test SBCs of several sizes and shapes in a newly developed equine stifle FEM with a TLS to determine how cyst size affects bone formation stimulation. This study found that a transcondylar screw is most effective in stimulating bone formation in cysts of greater height (proximal-distal). The TLS increases stress stimulus in the bone around the cyst to promote bone apposition and directs compression across the cyst. If full penetration of the screw through the cyst is possible, it is recommended that the transcondylar screw be used to treat subchondral bone cysts. For the treatment of smaller cysts that are not accessible by the current screw surgical approach, future work could study the efficacy of a dual-pitch headless screw that may reach smaller cysts.

Finite element analysis on dental implant[ndash ]supported prostheses without passive fit

2002 ◽  
Vol 11 (1) ◽  
pp. 30-40 ◽  
Author(s):  
Chatchai Kunavisarut ◽  
Lisa A. Lang ◽  
Brian R. Stoner ◽  
David A. Felton
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Dental Implant ◽  
Element Analysis ◽  
Passive Fit

Performance enhancement of normal contact ratio gearing system through correction factor

2019 ◽  
Vol 13 (3) ◽  
pp. 5242-5258
Author(s):  
R. Ravivarman ◽  
K. Palaniradja ◽  
R. Prabhu Sekar
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Correction Factor ◽  
Bending Strength ◽  
Performance Enhancement ◽  
Transmission Ratio ◽  
Contact Ratio ◽  
Element Analysis ◽  
Normal Contact ◽  
Root Region

As lined, higher transmission ratio drives system will have uneven stresses in the root region of the pinion and wheel. To enrich this agility of uneven stresses in normal-contact ratio (NCR) gearing system, an enhanced system is desirable to be industrialized. To attain this objective, it is proposed to put on the idea of modifying the correction factor in such a manner that the bending strength of the gearing system is improved. In this work, the correction factor is modified in such a way that the stress in the root region is equalized between the pinion and wheel. This equalization of stresses is carried out by providing a correction factor in three circumstances: in pinion; wheel and both the pinion and the wheel. Henceforth performances of this S+, S0 and S- drives are evaluated in finite element analysis (FEA) and compared for balanced root stresses in parallel shaft spur gearing systems. It is seen that the outcomes gained from the modified drive have enhanced performance than the standard drive.

Sign in / Sign up

Export Citation Format

Share Document