The pincers effect on cervical spinal cord in the development of traumatic cervical spinal cord injury without major fracture or dislocation.

ABSTRACT

STUDY DESIGN: Retrospective radiographic study. OBJECTIVE: To investigate the pincers effect on cervical spinal cord in the development of traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation. SETTING: The Japan LHWO Spinal Injuries Center. METHODS: Two hundred and twenty cases of traumatic CSCI without major fracture or dislocation were examined. The pinched diameters of the cervical spinal cord for 70 patients who complained of neck pain without neurological deficits were measured using sagittal-plane neutral and extension radiographs at 5 segments. These 70 patients were divided into 2 groups group A patients were less than 40 years old and group B patients were 41 or more. We defined the pinched ratio of the cervical spinal cord during extension as ((sagittal diameter in the neutral image)-(sagittal diameter in the extension image))/(sagittal diameter in the neutral image)*100. RESULTS: The incidence of traumatic CSCI without major fracture or dislocation at the C3-4, C4-5, C5-6 and C6-7 was 59.5, 25, 11.4 and 4.1%, respectively. Further, the pinched ratio of the cervical spinal cord at the C3-4 segment was significantly higher than that at the other segments. CONCLUSION: We concluded that the cervical spinal cord at the C3-4 segment might receive the highest bony impingement load during acute hyperextension of the cervical spine. The extreme pincers load on the cervical spinal cord at the C3-4 segment may have one of the important roles in the development of traumatic CSCI at the C3-4 segment.