Noguchi, MamikoGooyers, Chad EdwardHolmes, Michael W.R.Callaghan, Jack P.2017-03-212017-03-212015-02-23http://dx.doi.org/10.1080/23311916.2015.1014253http://hdl.handle.net/10012/11558Noguchi, M., Gooyers, C. E., Holmes, M. W. R., & Callaghan, J. P. (2015). The impact of compressive force magnitude on the in vitro neutral zone range and passive stiffness during a flexion-extension range of motion test. Cogent Engineering, 2(1). https://doi.org/10.1080/23311916.2015.1014253The objective of this work was to examine the influence of compressive force magnitude on a functional spinal unit’s (FSU) flexion–extension neutral zone measured during pure moment (PM) tests. Each porcine cervical FSU received four repeats of a PM test with 10, 300, 900 and 1,800 N of compressive force, in a randomized order. Increasing the magnitude of compression significantly decreased the neutral zone range (p < 0.001), while increasing passive stiffness (p < 0.001). The flexion limit at 10 N was significantly lower (p < 0.05) than the other loading conditions. Reporting the compressive force magnitude is important when posture is a standardized experimental factor considered in the design of in vitro spine biomechanics studies.enAttribution 4.0 InternationalNeutral zonePassive stiffnessCompressionFlexion–extension range of motion testIn vitroArticle