Internal bone remodeling

Keywords— internal bone remodeling, electric loading, magnetic loading, simulation. 

Simulation of the Effects of Electric and Magnetic Loadings on Internal Bone Remodeling... 

Qin Q, Ye J (2004) Thermoelectroelastic solutions for internal bone remodeling under axial and transverse loads. INT J SQLIDS STRUCT 41 2447-2460. 

Lanyon, L.E. (1984) Functional strain as a determinant for bone remodeling. Calcified Tissue International 36 S56-S61... 

Ramtani, S. (2008). Electro-mechanics of bone remodeling. International Journal of Engineering Science 46(11), 1173-1182. 

Crosbie, O.M., Freaney, R., and McKenna, M.J. 1999. Bone density, vitamin D status, and disordered bone remodeling in end-stage chronic liver disease . Calcified Tissue International, 64 295-300. 

Frost (1964) proposed two distinct categories of bone remodeling internal and surface remodeling. Surface remodeling refers to the case in which bone mass in deposited on or removed from the external surface of bone. In the internal remodeling procedure, bone material is added to or resorbed from the existing osteons [4], [2]. 

Cortical bone, also called compact or lamellar bone, is remodelled from woven bone by means of vascular channels that invade the embryonic bone from its periosteal and endosteal surfaces. It forms the internal and external tables of flat bones and the external surfaces of long bones. The primary structural unit is an osteon, also known as a Haversian system, a cylindrical shaped lamellar bone surrounding longitudinally oriented vascular channels (the Haversian canals). Horizontally oriented canals (Volkmann canals) connect adjacent osteons. The mechanical strength of cortical bone results from the tight packing of the osteons. 

Trabecular (cancellous) bone lies between cortical bone surfaces and consists of a network of honeycombed interstices containing haematopoietic elements and bony trabeculae. The trabeculae are predominantly oriented perpendicular to external forces to provide structural support. Trabecular bone continually undergoes remodelling on the internal endosteal surfaces. 

The elbow and wrist differ from most other joints in that certain movements (pronation/supination) are inextricably linked. This is accomplished by the mobile radius rotating around the static ulna. Proxi-mally, the radial head articulates with the radial notch on the lateral aspect of the coronoid process of the ulna. Distally, the ulnar notch of the radius rotates around the head of the ulna. In addition, the shafts of the bones are linked by the interosseous membrane. Damage to any of these structures may restrict pronation or supination. In adults, angulation or malrotation of more than 10 can result in restricted rotation of the forearm. For this reason, adult fractures are usually managed by open reduction and internal fixation. In children, the potential for remodelling is good around the wrist and more deformity can be accepted. 

Jowsey, J. (1971) The internal remodeling of bones, in The Biochemistry and Physiology of Bone III Development and Growth (ed. G.H. Bourne), Academic Press, New York, pp. 201-238. 

In this study, effects of different types of electromagnetic loading such as static, pulsed and sinusoidal fields on bone internal remodeling are evaluated. 

The amplitude of static (constant) magnetic can be a cause of changing the internal remodeling of bone. In order to investigate this effect, various values of amplitude were applied to the model and the model was run under these conditions. The amplitude values were chosen to be v /= -1, -0.5, 0, 0.5, 1 Amperes (A). The result of this simulation is shown in Fig. 4. 

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