Influence of Spinal Cord Compression and Traumatic Force on the Severity of Cervical Spinal Cord Injury Associated With Ossification of the Posterior Longitudinal Ligament

Study Design. Retrospective review. Objective. To evaluate the influence of static compression factors and dynamic factors based on the various degrees of traumatic force on the cervical spinal cord injury (SCI) in patients with ossification of the posterior longitudinal ligament. Summary of Background Data. Spinal cord disorder occurs as a result of various factors, including static factors and traumatic force. Discussions about the severity of paralysis resulting from SCI must therefore focus on dynamic factors based on the traumatic force as well as on static compression factors. However, the past reports did not describe the influence of traumatic force in detail. Methods. Fifty patients presenting with cervical SCI associated with ossification of the posterior longitudinal ligament were included in this study. The American Spinal Injury Association motor score 3 days after injury, the degree of the traumatic force, and the spinal cord compression rate were investigated, and the relationships among these factors were investigated. Results. Paralysis at the time of injury was not determined by static factors alone or by traumatic force alone. The severity of paralysis at the time of injury was determined on the basis of a combination of both the static factors and the degree of traumatic force. Conclusion. Both the degree of spinal cord compression and the degree of traumatic force were found to be important factors associated with the severity of cervical SCI in patients with ossification of the posterior longitudinal ligament.