Understanding the Effects of Thermal Elevations Associated With Orthopedic Intervention: An Experimental and Computational Investigation

Author(s):  
E. B. Dolan ◽  
T. J. Vaughan ◽  
G. L. Niebur ◽  
D. Tallon ◽  
L. M. McNamara

Specialized surgical cutting instruments are required to provide orthopedic surgeons with access to joints of the body, without causing extensive harm to native tissue, thus enhancing post-operative outcome. Orthopaedic intervention inevitably exposes bone tissue to elevated temperatures due to mechanical abrasion. Elevated temperatures lead to thermal necrosis and apoptosis of bone cells, surrounding soft tissue, bone marrow and stem cells crucial for postoperative healing (1–4). Thermally damaged bone tissue is subsequently resorbed and in severe cases replaced by connective tissue (2, 5) Bone thermal damage occurs when the local temperature exceeds a thermal threshold, largely recognised as ≥47°C (4, 6). Furthermore, it has been proposed that the area of bone to experience thermal damage is directly proportional to the duration of exposure to the heat source (7, 8). However, precise thermal elevations occurring throughout bone during surgical cutting are not well defined. It is also unclear whether temperatures generated in osteocytes in vivo are sufficient to induce cellular responses. Experimental analysis of temperature generation throughout bone is challenging due to its complex heterogeneous composition. There is a specific need for advanced 3D computational models that incorporate multi-scale variability in both bone tissue composition and thermal properties to predict how organ level thermal elevations are distributed throughout bone cells and tissue during orthopaedic cutting procedures.

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 905 ◽  
Author(s):  
Francesca Donnaloja ◽  
Emanuela Jacchetti ◽  
Monica Soncini ◽  
Manuela T. Raimondi

Bone tissue is the structural component of the body, which allows locomotion, protects vital internal organs, and provides the maintenance of mineral homeostasis. Several bone-related pathologies generate critical-size bone defects that our organism is not able to heal spontaneously and require a therapeutic action. Conventional therapies span from pharmacological to interventional methodologies, all of them characterized by several drawbacks. To circumvent these effects, tissue engineering and regenerative medicine are innovative and promising approaches that exploit the capability of bone progenitors, especially mesenchymal stem cells, to differentiate into functional bone cells. So far, several materials have been tested in order to guarantee the specific requirements for bone tissue regeneration, ranging from the material biocompatibility to the ideal 3D bone-like architectural structure. In this review, we analyse the state-of-the-art of the most widespread polymeric scaffold materials and their application in in vitro and in vivo models, in order to evaluate their usability in the field of bone tissue engineering. Here, we will present several adopted strategies in scaffold production, from the different combination of materials, to chemical factor inclusion, embedding of cells, and manufacturing technology improvement.


2014 ◽  
Vol 136 (2) ◽  
Author(s):  
Eimear B. Dolan ◽  
Ted J. Vaughan ◽  
Glen L. Niebur ◽  
Conor Casey ◽  
David Tallon ◽  
...  

During orthopaedic surgery elevated temperatures due to cutting can result in bone injury, contributing to implant failure or delayed healing. However, how resulting temperatures are experienced throughout bone tissue and cells is unknown. This study uses a combination of experiments (forward-looking infrared (FLIR)) and multiscale computational models to predict thermal elevations in bone tissue and cells. Using multiple regression analysis, analytical expressions are derived allowing a priori prediction of temperature distribution throughout bone with respect to blade geometry, feed-rate, distance from surface, and cooling time. This study offers an insight into bone thermal behavior, informing innovative cutting techniques that reduce cellular thermal damage.


2020 ◽  
Vol 27 (6) ◽  
pp. 838-853 ◽  
Author(s):  
Madalina Icriverzi ◽  
Valentina Dinca ◽  
Magdalena Moisei ◽  
Robert W. Evans ◽  
Mihaela Trif ◽  
...  

: Among the multiple properties exhibited by lactoferrin (Lf), its involvement in bone regeneration processes is of great interest at the present time. A series of in vitro and in vivo studies have revealed the ability of Lf to promote survival, proliferation and differentiation of osteoblast cells and to inhibit bone resorption mediated by osteoclasts. Although the mechanism underlying the action of Lf in bone cells is still not fully elucidated, it has been shown that its mode of action leading to the survival of osteoblasts is complemented by its mitogenic effect. Activation of several signalling pathways and gene expression, in an LRPdependent or independent manner, has been identified. Unlike the effects on osteoblasts, the action on osteoclasts is different, with Lf leading to a total arrest of osteoclastogenesis. : Due to the positive effect of Lf on osteoblasts, the potential use of Lf alone or in combination with different biologically active compounds in bone tissue regeneration and the treatment of bone diseases is of great interest. Since the bioavailability of Lf in vivo is poor, a nanotechnology- based strategy to improve the biological properties of Lf was developed. The investigated formulations include incorporation of Lf into collagen membranes, gelatin hydrogel, liposomes, loading onto nanofibers, porous microspheres, or coating onto silica/titan based implants. Lf has also been coupled with other biologically active compounds such as biomimetic hydroxyapatite, in order to improve the efficacy of biomaterials used in the regulation of bone homeostasis. : This review aims to provide an up-to-date review of research on the involvement of Lf in bone growth and healing and on its use as a potential therapeutic factor in bone tissue regeneration.


2022 ◽  
Vol 5 (1) ◽  
pp. 8
Author(s):  
Giorgia Borciani ◽  
Giorgia Montalbano ◽  
Nicola Baldini ◽  
Chiara Vitale-Brovarone ◽  
Gabriela Ciapetti

New biomaterials and scaffolds for bone tissue engineering (BTE) applications require to be tested in a bone microenvironment reliable model. On this assumption, the in vitro laboratory protocols with bone cells represent worthy experimental systems improving our knowledge about bone homeostasis, reducing the costs of experimentation. To this day, several models of the bone microenvironment are reported in the literature, but few delineate a protocol for testing new biomaterials using bone cells. Herein we propose a clear protocol to set up an indirect co-culture system of human-derived osteoblasts and osteoclast precursors, providing well-defined criteria such as the cell seeding density, cell:cell ratio, the culture medium, and the proofs of differentiation. The material to be tested may be easily introduced in the system and the cell response analyzed. The physical separation of osteoblasts and osteoclasts allows distinguishing the effects of the material onto the two cell types and to evaluate the correlation between material and cell behavior, cell morphology, and adhesion. The whole protocol requires about 4 to 6 weeks with an intermediate level of expertise. The system is an in vitro model of the bone remodeling system useful in testing innovative materials for bone regeneration, and potentially exploitable in different application fields. The use of human primary cells represents a close replica of the bone cell cooperation in vivo and may be employed as a feasible system to test materials and scaffolds for bone substitution and regeneration.


Author(s):  
Pia Schneeweiss ◽  
Dorin Panescu ◽  
Dominik Stunder ◽  
Mark W. Kroll ◽  
Christopher J. Andrews ◽  
...  

AbstractElectric contact currents (CC) can cause muscle contractions, burns, or ventricular fibrillation which may result in life-threatening situations. In vivo studies with CC are rare due to potentially hazardous effects for participants. Cadaver studies are limited to the range of tissue’s electrical properties and the utilized probes’ size, relative position, and sensitivity. Thus, the general safety standards for protection against CC depend on a limited scientific basis. The aim of this study was therefore to develop an extendable and adaptable validated numerical body model for computational CC dosimetry for frequencies between DC and 1 MHz. Applying the developed model for calculations of the IEC heart current factors (HCF) revealed that in the case of transversal CCs, HCFs are frequency dependent, while for longitudinal CCs, the HCFs seem to be unaffected by frequency. HCFs for current paths from chest or back to hand appear to be underestimated by the International Electrotechnical Commission (IEC 60479-1). Unlike the HCFs provided in IEC 60479-1 for longitudinal current paths, our work predicts the HCFs equal 1.0, possibly due to a previously unappreciated current flow through the blood vessels. However, our results must be investigated by further research in order to make a definitive statement. Contact currents of frequencies from DC up to 100 kHz were conducted through the numerical body model Duke by seven contact electrodes on longitudinal and transversal paths. The resulting induced electric field and current enable the evaluation of the body impedance and the heart current factors for each frequency and current path.


2014 ◽  
Vol 783-786 ◽  
pp. 72-77 ◽  
Author(s):  
Takayoshi Nakano ◽  
Aira Matsugaki ◽  
Takuya Ishimoto ◽  
Mitsuharu Todai ◽  
Ai Serizawa ◽  
...  

Bone microstructure is dominantly composed of anisotropic extracellular matrix (ECM) in which collagen fibers and epitaxially-oriented biological apatite (BAp) crystals are preferentially aligned depending on the bone anatomical position, resulting in exerting appropriate mechanical function. The regenerative bone in bony defects is however produced without the preferential alignment of collagen fibers and the c-axis of BAp crystals, and subsequently reproduced to recover toward intact alignment. Thus, it is necessary to produce the anisotropic bone-mimetic tissue for the quick recovery of original bone tissue and the related mechanical ability in the early stage of bone regeneration. Our group is focusing on the methodology for regulating the arrangement of bone cells, the following secretion of collagen and the self-assembled mineralization by oriented BAp crystallites. Cyclic stretching in vitro to bone cells, principal-stress loading in vivo on scaffolds, step formation by slip traces on Ti single crystal, surface modification by laser induced periodic surface structure (LIPSS), anisotropic collagen substrate with the different degree of orientation, etc. can dominate bone cell arrangement and lead to the construction of the oriented ECM similar to the bone tissue architecture. This suggests that stress/strain loading, surface topography and chemical anisotropy are useful to produce bone-like microstructure in order to promote the regeneration of anisotropic bone tissue and to understand the controlling parameters for anisotropic osteogenesis induction.


1974 ◽  
Vol 61 (2) ◽  
pp. 427-439 ◽  
Author(s):  
Itzhak Binderman ◽  
Dan Duksin ◽  
Arieh Harell ◽  
Ephraim Katzir (Katchalski) ◽  
Leo Sachs

A system is described for the formation of bone tissue in culture from isolated rat bone cells. The isolated bone cells were obtained from embryonic rat calvarium and periosteum or from traumatized, lifted periosteum of young rats. The cells were cultured for a period of up to 8 wk, during which time the morphological, biochemical, and functional properties of the cultures were studied. Formation of bone tissue by these isolated bone cells was shown, in that the cells demonstrated osteoblastic morphology in light and electron microscopy, the collagen formed was similar to bone collagen, there was mineralization specific for bone, and the cells reacted to the hormone calcitonin by increased calcium ion uptake. Calcification of the fine structure of the cells and the matrix is described. Three stages in the calcification process were observed by electron microscopy. It is concluded that these bone cells growing in vitro are able to function in a way similar to such cells in vivo. This tissue culture system starting from isolated bone cells is therefore suitable for studies on the structure and function of bone.


2016 ◽  
Vol 13 (119) ◽  
pp. 20160337 ◽  
Author(s):  
Eimear B. Dolan ◽  
David Tallon ◽  
Wing-Yee Cheung ◽  
Mitchell B. Schaffler ◽  
Oran D. Kennedy ◽  
...  

Bone is often subject to harsh temperatures during orthopaedic procedures resulting in thermally induced bone damage, which may affect the healing response. Postsurgical healing of bone is essential to the success of surgery, therefore, an understanding of the thermally induced responses of bone cells to clinically relevant temperatures in vivo is required. Osteocytes have been shown to be integrally involved in the bone remodelling cascade, via apoptosis, in micro-damage systems. However, it is unknown whether this relationship is similar following thermal damage. Sprague–Dawley rat tibia were exposed to clinically relevant temperatures (47°C or 60°C) to investigate the role of osteocytes in modulating remodelling related factors. Immunohistochemistry was used to quantify osteocyte thermal damage (activated caspase-3). Thermally induced pro-osteoclastogenic genes ( Rankl , Opg and M-csf ), in addition to genes known to mediate osteoblast and osteoclast differentiation via prostaglandin production ( Cox2 ), vascularization ( Vegf ) and inflammatory ( Il1a ) responses, were investigated using gene expression analysis. The results demonstrate that heat-treatment induced significant bone tissue and cellular damage. Pro-osteoclastogenic genes were upregulated depending on the amount of temperature elevation compared with the control. Taken together, the results of this study demonstrate the in vivo effect of thermally induced osteocyte damage on the gene expression profile.


2012 ◽  
Vol 86 ◽  
pp. 17-21 ◽  
Author(s):  
H. Sakai ◽  
Teruo Asaoka

Due to the merits of zirconia ceramics such as high strength, toughness, abrasion resistance, and chemical stability in vivo, yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) are currently used in the femoral head of hip prostheses. However, this material has a limited applications range because it is a bioinert material that does not interact with bone tissue and thus does not easily integrate directly in the bone. Therefore, we need to add different material’s layer which enables in vivo formation of bone-like apatite layer that exhibits bioactivity , composite compound bioactive ceramics, and facilitates interactions and integration in bone tissue. In addition, by developing a surface structure that enhances mechanical bonding, this material can be expected to be used as an alternative aggregate under load bearing conditions. In the present study, various method were carried out with the objective of controlling interactions between zirconia ceramics and the body such as structural design of the material surface, addition of bioactivity using reagents treatment, confirmation of formation of the apatite layer using immersion in simulated body fluid, wettability testing and develop structure with mechanical properties equal to bone strength.


2021 ◽  
Vol 14 (3) ◽  
pp. 159-164
Author(s):  
Leonardo Leonardi ◽  
◽  
Roberto Marsili ◽  
Enrico Bellezza ◽  
Giovanni Angeli ◽  
...  

Additive manufacturing (AM) is the process of joining materials to create layer-by-layer three-dimensional objects using a 3D printer from a digital model. The great advantage of Additive Manufacturing is to allow a freer design than traditional processes. The development of additive manufacturing processes has permitted to optimize the production of the customized product through the modeling of the geometry and the knowledge of the morphometric parameters of the body structures. 3D printing has revolutionized the field of Regenerative Medicine because, starting from computerized tomography (CT) images and using traditional materials such as plastic and metals, it can provide customized prostheses for each patient, which adapt perfectly to the needs of the subject and act as structures support. 3D printing allows you to print three-dimensional porous scaffolds with a precise shape and chemical composition suitable for medical and veterinary use. Some of these scaffolds are biodegradable and appear to be ideal for bone tissue engineering. In fact, they are able to simulate extracellular matrix properties that allow mechanical support, favoring mechanical interactions and providing a model for cellular attachment and in vivo stimulation of bone tissue formation.


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