0
TECHNICAL PAPERS

Spatial Micromovements of Uncemented Femoral Components After Torsional Loads

[+] Author and Article Information
W. Görtz

Biomechanical Research Laboratory, Orthopaedic Surgery Hospital, University of Heidelberg, Schlierbacher Landstr. 200a, 69118 Heidelberg, Germany

U. V. Nägerl

Max-Planck Institute of Neurobiology, Am Klopferspitz 18A, 82152 München-Martinsried, Germany

H. Nägerl

IV. Physical Institute, University of Göttingen, Bunsenstr. 13-15, 37073 Göttingen, Germany

M. Thomsen

Biomechanical Research Laboratory, Orthopaedic Surgery Hospital, University of Heidelberg, Schlierbacher Landstr. 200a, 69118 Heidelberg, Germanye-mail: Marc.Thomsen@ok.uni-heidelberg.de

J Biomech Eng 124(6), 706-713 (Dec 27, 2002) (8 pages) doi:10.1115/1.1517565 History: Received September 01, 2001; Revised July 01, 2002; Online December 27, 2002
Copyright © 2002 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
The axial torque was produced by weights w1 (30 N) and w2 (30 N) whose horizontal distance was adjusted by two computer-controlled steppermotors. The weights w3 and w4 produced the axial preload of 80 N.
Grahic Jump Location
A-D. Survey of the 4 prostheses: (A) ABG, (B) CLS, (C) S-ROM, (D) Alloclassic
Grahic Jump Location
Survey of the levels of the measured sites with respect to the lesser trochanter
Grahic Jump Location
Insert from Fig. 1 showing the six dimensional measuring system. Six linear variable differential transducers in a three (S1, S2, S3)-two (S4, S5)-one (S6) setting to measure the spatial position of the movable cube shown here rigidly tied to the site #3 (8 cm below the lesser trochanter).
Grahic Jump Location
Rotational angle α as a function of torque Tz: typical characteristics. The dashed line represents the linear fit.
Grahic Jump Location
A-D. Examples of the 4 typical patterns of torque transfer. The micromotions between stem twist and bone twist are graphically indicated. The ordinate shows rotational displacement in millidegrees/Nm. The abscissa reveals these measurements dependent on site of measurement. Graph A (ABG) is typical for a proximal fixation. Graph B (CLS) represents proximal torque transfer with more distal fixation then A (distally shifted). The S-ROM (C) has proximal and distal torque transfer (overall fixation). Note that there is movement between sleeve and stem. The Alloclassic (D) is a representative for distal fixation with significant rotational displacement in the proximal part.
Grahic Jump Location
Distal limit of the area of maximum torque transfer to the composite femur for the 4 prostheses

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In