The interspinal ligaments (interspinous ligaments) are thin and membranous ligaments, that connect adjoining spinous processes of the vertebra in the spine. They extend from the root to the apex of each spinous process. They meet the ligamenta flava in front and blend with the supraspinal ligament behind.
The ligaments are narrow and elongated in the thoracic region, broader, thicker, and quadrilateral in form in the lumbar region, and only slightly developed in the neck. In the neck they are often considered part of the nuchal ligament.
The function of the interspinal ligaments is to limit flexion of the spine.
This article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)
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