scholarly journals Quantitative CT with finite element analysis: towards a predictive tool for bone remodelling around an uncemented tapered stem

2012 ◽  
Vol 36 (7) ◽  
pp. 1363-1369 ◽  
Author(s):  
Vickie B. Shim ◽  
Rocco P. Pitto ◽  
Iain A. Anderson
2016 ◽  
Vol 2 (1) ◽  
pp. 643-647 ◽  
Author(s):  
Josephine Mauck ◽  
Jan Wieding ◽  
Daniel Kluess ◽  
Rainer Bader

AbstractThe numerical simulation of bone remodelling provides a great opportunity to improve the choice of therapy in particular for complex bone defects. Despite this fact, its use in clinical practice is not yet expedient because of several unresolved problems. In this paper a new bone remodelling algorithm based on standard computer tomography datasets and finite element analysis is introduced.


2013 ◽  
Vol 168 (3) ◽  
pp. 457-464 ◽  
Author(s):  
Elizabeth A Lawson ◽  
Kathryn E Ackerman ◽  
Nara Mendes Estella ◽  
Gabriela Guereca ◽  
Lisa Pierce ◽  
...  

ObjectivePreclinical data indicate that oxytocin, a hormone produced in the hypothalamus and secreted into the peripheral circulation, is anabolic to bone. Oxytocin knockout mice have severe osteoporosis, and administration of oxytocin improves bone microarchitecture in these mice. Data suggest that exercise may modify oxytocin secretion, but this has not been studied in athletes in relation to bone. We therefore investigated oxytocin secretion and its association with bone microarchitecture and strength in young female athletes.DesignCross-sectional study of 45 females, 14–21 years (15 amenorrheic athletes (AA), 15 eumenorrheic athletes (EA), and 15 nonathletes (NA)), of comparable bone age and BMI.MethodsWe used high-resolution peripheral quantitative CT to assess bone microarchitecture and finite element analysis to estimate bone strength at the weight-bearing distal tibia and non-weight-bearing ultradistal radius. Serum samples were obtained every 60 min, 2300–0700 h, and pooled for an integrated measure of nocturnal oxytocin secretion. Midnight and 0700 h samples were used to assess diurnal variation of oxytocin.ResultsNocturnal oxytocin levels were lower in AA and EA than in NA. After controlling for estradiol, the difference in nocturnal oxytocin between AA and NA remained significant. Midnight and 0700 h oxytocin levels did not differ between groups. At the tibia and radius, AA had impaired microarchitecture compared with NA. In AA, nocturnal oxytocin correlated strongly with trabecular and cortical microarchitecture, particularly at the non-weight-bearing radius. In regression models that include known predictors of microarchitecture in AA, oxytocin accounted for a substantial portion of the variability in microarchitectural and strength parameters.ConclusionsNocturnal oxytocin secretion is low in AA compared with NA and associated with site-dependent microarchitectural parameters. Oxytocin may contribute to hypoestrogenemic bone loss in AA.


Author(s):  
Dan Dragomir-Daescu ◽  
Asghar Rezaei ◽  
Susheil Uthamaraj ◽  
Timothy Rossman ◽  
James T. Bronk ◽  
...  

Author(s):  
Yogesh Deepak Bansod ◽  
Maeruan Kebbach ◽  
Daniel Kluess ◽  
Rainer Bader ◽  
Ursula van Rienen

AbstractBone tissue exhibits piezoelectric properties and thus is capable of transforming mechanical stress into electrical potential. Piezoelectricity has been shown to play a vital role in bone adaptation and remodelling processes. Therefore, to better understand the interplay between mechanical and electrical stimulation during these processes, strain-adaptive bone remodelling models without and with considering the piezoelectric effect were simulated using the Python-based open-source software framework. To discretise numerical attributes, the finite element method (FEM) was used for the spatial variables and an explicit Euler scheme for the temporal derivatives. The predicted bone apparent density distributions were qualitatively and quantitatively evaluated against the radiographic scan of a human proximal femur and the bone apparent density calculated using a bone mineral density (BMD) calibration phantom, respectively. Additionally, the effect of the initial bone density on the resulting predicted density distribution was investigated globally and locally. The simulation results showed that the electrically stimulated bone surface enhanced bone deposition and these are in good agreement with previous findings from the literature. Moreover, mechanical stimuli due to daily physical activities could be supported by therapeutic electrical stimulation to reduce bone loss in case of physical impairment or osteoporosis. The bone remodelling algorithm implemented using an open-source software framework facilitates easy accessibility and reproducibility of finite element analysis made.


Sign in / Sign up

Export Citation Format

Share Document