SPINE

Gregory J. Przybylski, MD, Prakash R. Patel, MD, Gregory J. Carlin, MS, Savio L-Y. Woo, PhD


Study Design. The quantitative anthropometry of the cervical longitudinal ligaments was determined in 20 human cadaveric subatlantal cervical spines at the limits of flexion and extension.

Objectives. To provide measurements of cervical anterior and posterior longitudinal ligament lengths, widths, and cross-sectional areas at segmental levels.

Summary of Background Data. Although mathematical models of the cervical spine require specific data to predict kinematics, the anthropometry of the cervical spine has not been examined in detail. The dimensional changes of ligaments in physiologic motion are not well characterized.

Methods. Segmental lenths and widths of the cervical longitudinal ligaments were measured in sagittal plane flexion and extension, using a three-dimentsional electromagnetic digitizer. The cross-sectional areas fo the ligaments at resting lengths were measured with a laser micrometer system. Comparisons between anterior and posterior location and among segmental levels were made. Several ligaments were examined histologically to determine the insertion sites and, thus, to define the segmental length.

Conclusions. The quantitative anthropometry of the cervical longitudinal ligaments is important in the development of accurate mathematical models of the cervical spine. The in situ ligaments may not be under tension. [Key words: cervical vertebrae, ligaments, quantitative anatomy].