Clinical anatomy of ligamentum nuchae.

In view of the disparities in the anatomical, clinical, and biomechanical literature this study was undertaken to reappraise the gross anatomy of ligamentum nuchae with the objective of providing an accurate anatomical basis for biomechanical studies and for clinical theories and practices. Ligamentum nuchae was studied by gross dissection in ten embalmed human adult cadavers and was found to be comprised of two structures: a dorsal raphe and a midline fascial septum. The dorsal raphe was formed by the interweaving of the right and left upper trapezius, splenius capitis, and rhomboid minor. It spanned the cervical spine and was firmly attached to the external occipital protuberance and to the spinous process of C7. The fascial septum consisted of dense connective tissue and ran ventrally from the midline raphe to be confluent with the interspinous ligaments and atlanto-axial and atlanto-occipital membranes. These findings agree with those anatomical descriptions that portray ligamentum nuchae as a two-part structure but not with those studies in which it is characterized as a strong ligament attaching to all cervical spinous processes. Importantly, the findings of this study emphasize the need for clinical and biomechanical literature to portray the gross anatomy of ligamentum nuchae accurately.