de.mpg.escidoc.pubman.appbase.FacesBean
English
 
Help Guide Disclaimer Contact us Login
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Journal Article

Combining 3D tracking and surgical instrumentation to determine the stiffness of spinal motion segments: A validation study

MPS-Authors
http://pubman.mpdl.mpg.de/cone/persons/resource/persons84187

Gédet P, Büchler P, Kowal J, Rudolph T, Burger J, Scheffler,  K
Department High-Field Magnetic Resonance, Max Planck Institute for Biological Cybernetics, Max Planck Society;

Locator
There are no locators available
Fulltext (public)
There are no public fulltexts available
Supplementary Material (public)
There is no public supplementary material available
Citation

Reutlinger, C., Gédet P, Büchler P, Kowal J, Rudolph T, Burger J, Scheffler, K., & Hasler, C. (2011). Combining 3D tracking and surgical instrumentation to determine the stiffness of spinal motion segments: A validation study. Medical Engineering Physics, 33(3), 340-346. doi:10.1016/j.medengphy.2010.10.021.


Cite as: http://hdl.handle.net/11858/00-001M-0000-0013-BC22-7
Abstract
The spine is a complex structure that provides motion in three directions: flexion and extension, lateral bending and axial rotation. So far, the investigation of the mechanical and kinematic behavior of the basic unit of the spine, a motion segment, is predominantly a domain of in vitro experiments on spinal loading simulators. Most existing approaches to measure spinal stiffness intraoperatively in an in vivo environment use a distractor. However, these concepts usually assume a planar loading and motion. The objective of our study was to develop and validate an apparatus, that allows to perform intraoperative in vivo measurements to determine both the applied force and the resulting motion in three dimensional space. The proposed setup combines force measurement with an instrumented distractor and motion tracking with an optoelectronic system. As the orientation of the applied force and the three dimensional motion is known, not only force–displacement, but also moment-angle relations could be determined. The validation was performed using three cadaveric lumbar ovine spines. The lateral bending stiffness of two motion segments per specimen was determined with the proposed concept and compared with the stiffness acquired on a spinal loading simulator which was considered to be gold standard. The mean values of the stiffness computed with the proposed concept were within a range of ±15 compared to data obtained with the spinal loading simulator under applied loads of less than 5 Nm.