Collagen organisation in the interspinous ligament and its relationship to tissue function
Aspden, R.M.; Bornstein, N.H.; Hukins, D.W.
Journal of Anatomy 155: 141-151
1987
ISSN/ISBN: 0021-8782 PMID: 3332272 Document Number: 287875
X-Ray diffraction and determination of optical anistropy show that collagen fibres in pig and human lumbar interspinuous ligaments tend to be oriented parallel to the spinous processes. There is a distribution of fibre orientations about this preferred direction. Flexion of the spine does not change the direction of preferred orientation but the angular spread of fibres increases. This pattern of collagen fibre orientations is consistent with the interspinuous ligaments being able to transmit tension from the thoracolumbar fascia to the vertebrae. Since the collagen fibres tend to be aligned antero-posteriorly, they provide a high efficiency of reinforcement in this direction. The lack of fibres oriented perpendicular to the spinous processes will lead to low strength in the cranio-caudal direction so that the ligament can provide little resistance to flexion of the spine.