191. A PROSPECTIVE ANALYSIS COMPARING PREOPERATIVE MRI TO DIAGNOSE DISRUPTION OF THE POSTERIOR LIGAMENTOUS COMPLEX IN CERVICAL SPINE INJURY AND INTRAOPERATIVE FINDINGS

Abstract

Purpose: The decision of whether or not an injury to the sub-axial cervical spine needs operative management often hinges on the stability of the spine. The posterior Ligamentous Complex (PLC) is one of the primary soft tissue stabilizers of the cervical spine. Fat-saturated T2-wieghted MRI sequences are able to demonstrate soft tissue injury to the cervical spine. No studies to date have assessed the ability of MRI to accurately and reliably demonstrate PLC disruption in the sub-axial cervical spine.

Method: Forty-nine consecutive patients aged 14–85 years presenting to the two participating institutions with injury between C3 and T1 who required posterior surgery as part of their management were prospectively enrolled in the study. All patients had radiographs, CT, and MRI scans preoperatively, which were reviewed by a Neuroradiologist, and the treating surgeon separately. Their posterior intraoperative findings were then recorded by the treating surgeon and his assistant. Statistical analysis included Spearman’s rank order correlation, and Cohen’s kappa score.

Results: There was a moderate level of agreement between the radiologist’s interpretation of the preopera-tive MRI and the surgeon’s intraoperative findings for the supraspinous and intraspinous ligaments, (kappa.49 & .48 respectively). A fair level of agreement was found for the ligamentum flavum, left and right facet capsules, and the cervical fascia (kappa scores.31,.30,.30,.39 respectively).

Conclusion: MRI has a high sensitivity (78.6% to 100%) for detecting cervical PLC injury but a low specificity (53.6% to 75%). On its own MRI is not a useful tool for diagnosing cervical spine PLC injury. The clinician should be aware of the relatively high rate of false positive PLC injury diagnosis with MRI.