**5. References**


<sup>\*</sup> Corresponding Author

[7] Moskalenko YuE, 1967. Dynamics of the brain blood volume under normal conditions and gravitational stresses. Nauka Press, Leningrad. (English translation: NASA-TT F-492).

78 Injury and Skeletal Biomechanics

elements.

**Author details** 

Yuri Moskalenko\*

Tamara Kravchenko

Natalia Ryabchikova

Peter Halvorson *ITAG, PA, USA* 

**5. References** 

Corresponding Author

 \*

Klagenfurt: Kartner Druckerei. 36p.

*Petersburg, Russian Federation* 

slow skull bone motions is looks definite confirmed.

as nearly united system. Intracranial liquid system is an initial movement of this slow fluctuation process. It is not yet final point of view how developing all connected with this processes and origin of this initial liquids movement is not clear yet. However, the fact of

Although the current role in skull bone movements play mechanical properties of sutures, because separate bone of skull are mechanically too strong to be deformed by arterial pressure forces or other origin forces, which occur inside cranial cavity. Thus, final result of the skull expanding of slow skull bone motions are depends on not structure and biomechanics of some particular suture, but of skull, as united complicated bio-mechanical system. Biomechanical properties single elements composed skull as united moveable system and this is a new property, which is appeared on systemic level. Mechanical properties of the united mechanical system may be different, to compare with any single

, Gustav Weinstein and Julia Andreeva

*Russian School of Osteopathic Medicine, Moscow, Russian Federation* 

*Biological Faculty Moscow State University, Moscow, Russian Federation* 

*Institute of Evolutionary Physiology and Biochemistry, Russian Academy of Sciences, Sankt* 

[1] Mednikova MB. 2004. Skull trepanation in ancient times. Aleteya: Moskow. 206p. [2] Mogle P, Zias J. 1995. Trephination as a possible treatment for scurvy in a middle bronze age (ca. 2200 B.C.) skeleton. Intern. J. of Osteoarchaeology. V.5 p.77-81. [3] Jenkner F. 1966.Prähistorische und präcolumbianische Schädeltrepanationen.

[6] Moskalenko YuE, Naumenko AI, 1957. About oscillatory movements of CSF in

[4] Cushing H, Studies in Intracranial Physiology and Surgery, London, 1926. [5] Sepp EK, Die Dynamik der Blutzirkulation im Gehirn, Springer, Berlin, 1928.

craniospinal cavity. Physiol. J. USSR. V.43. No.10. p.928-933.


[23] Sutherland WG, 1939. The Cranial Bowl. A Treatise Relating to Cranial Mobility, Cranial Articular Lesions and Cranial Techniques,. Free Press Co, Mankato, MN.

**Chapter 5** 

© 2012 Filipov, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

© 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

distribution, and reproduction in any medium, provided the original work is properly cited.

and reproduction in any medium, provided the original work is properly cited.

**Biomechanics of the Fractured Femoral Neck –** 

The femoral neck fracture is subjected to powerful shearing forces due to the angular, spirallike architecture of the proximal femur. Under the conditions of severe *osteoporosis*, the *femoral neck* consists of cortical walls, enveloping soft cancellous bone, having unimportant mechanical significance, and the neck can often be looked at as a hollow cylinder. If the condition of patient is not appropriate for total hip replacement (mental diseases or other risks), and a decision is made for a screw fixation, the implanted screws must be solidly fixed in the distal fragment in at least two points in order to provide resistance to the shearing forces in case of osteoporosis. The traditional screw fixation methods, however, do not meet the above-named requirement. Present-day popular *traditional methods* of femoral neck fixation, which are performed by three cancellous screws, placed parallel to each other and parallel to the femoral neck axis, are associated with poor results in 20 to 42% [1,2,3,4,5]. The high failure rate of traditional screw fixation methods can be explained by the presence of a number of related biomechanical imperfections. (1) *Instability of the construction regarding varus stress.* The entry points of the three screws in traditional screw fixation methods are located at the thin, fragile cortex of the greater trochanter or close to it. The screws are often placed in the soft cancellous bone near the axis of the femoral neck, with no cortical support [6]. Even if one or two of the distal screws are placed close to the distal cortex of the femoral neck, they lack any second solid point of support. A second point of support for them is the thin and fragile lateral cortex of the greater trochanter – their entry point. Such a construction can rely only on the interfragmental compression, generated by the intraoperative tightening of the screws, but the achieving of compression depends on the

**The New BDSF-Method of Positioning** 

**the Implant as a Simple Beam with** 

**an Overhanging End** 

Additional information is available at the end of the chapter

Orlin Filipov

http://dx.doi.org/10.5772/47839

**1. Introduction** 

