Fig. 5.

Change in fibre curvature is linked to tissue morphology and fibre orientation. (ai) Magnitude of anterior fibre curvature change increases with AF depth with little change displayed in outer AF. (aii) Fibre curvature change for inner AF. A group of fibres show an increase in curvature (red) whereas others straighten (blue) suggesting tissue morphology changes. (bi) Overall a higher change in curvature was found throughout the posterior-lateral region. (bii) Displaying two consecutive lamellae shows an alternating pattern of higher increase in curvature and lower increase in curvature or straightening. Changes in curvature were higher for more vertically orientated fibres i.e. curvature changes were more dominant in vertical direction (bulging of the disc). (biii) Change in curvature plotted for individual lamellae showing alternating pattern (c) Regional comparison of change in fibre curvature. Anterior fibre curvature change has a gradual increase with depth. Variation in anterior region is due to localised tissue morphology changes, mostly found in inner lamellae. Variation in the posterior-lateral region is due to whole AF deformation and fibre orientation. Inner-middle posterior-lateral fibres had the most prominent pattern in alternating high and lower increase in curvature as indicated by a bimodal distribution. Notably, higher curvature changes were present in all posterior-lateral groups when compared to anterior groups. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)