The application of physiological loading using a dynamic, multi-axis spine simulator

Timothy Holsgrove, Anthony Miles, Sabina Gheduzzi

Research output: Contribution to journalArticle

1 Citation (Scopus)
65 Downloads (Pure)

Abstract

In-vitro testing protocols used for spine studies should replicate the in-vivo load environment as closely as possible. Unconstrained moments are regularly employed to test spinal specimens in-vitro, but applying such loads dynamically using an active six-axis testing system remains a challenge. The aim of this study was to assess the capability of a custom-developed spine simulator to apply dynamic unconstrained moments with an axial preload.

Flexion–extension, lateral bending, and axial rotation were applied to an L5/L6 porcine specimen at 0.1 and 0.3Hz. Non-principal moments and shear forces were minimized using load control. A 500N axial load was applied prior to tests, and held stationary during testing to assess the effect of rotational motion on axial load.

Non-principal loads were minimized to within the load cell noise-floor at 0.1Hz, and within two-times the load-cell noise-floor in all but two cases at 0.3Hz. The adoption of position control in axial compression–extension resulted in axial loads with qualitative similarities to in-vivo data.

This study successfully applied dynamic, unconstrained moments with a physiological preload using a six-axis control system. Future studies will investigate the application of dynamic load vectors, multi-segment specimens, and assess the effect of injury and degeneration.
Original languageEnglish
Pages (from-to)74-80
Number of pages7
JournalMedical Engineering & Physics
Volume41
Early online date31 Dec 2016
DOIs
Publication statusPublished - Mar 2017

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Axial loads
Noise
Spine
Simulators
Testing
Swine
Axial compression
Position control
Dynamic loads
Loads (forces)
Wounds and Injuries
Control systems
In Vitro Techniques

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The application of physiological loading using a dynamic, multi-axis spine simulator. / Holsgrove, Timothy; Miles, Anthony; Gheduzzi, Sabina.

In: Medical Engineering & Physics , Vol. 41, 03.2017, p. 74-80.

Research output: Contribution to journalArticle

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