Abstract
BACKGROUND: Upper extremity radicular pain is commonly treated with a cervical transforaminal epidural steroid injection (CTFESI). Recently, a new technique, the modified approach CTFESI, has been developed with a theoretical safety advantage to avoid the neurovascular structures. This approach requires an angle measurement of the superior articular process (SAP) on MRI. The inter-rater reliability of this angle measurement among practicing physicians is yet to be investigated. OBJECTIVE: The purpose of this study was to determine the inter-rater reliability of SAP angle measurements on MRI. METHODS: Three raters independently measured the SAP angle on 50 cervical MRIs. A two-way, mixed effects, absolute agreement, single rater statistical model was used to determine the intraclass correlation coefficient (ICC) between all three raters, as well as between each pair of raters. RESULTS: Inter-rater reliability among all raters showed good reliability with an ICC = 0.837709 (95% CI 0.75-0.9, p < 0.001). Similarly, good inter-rater reliability was found between each of the pairs of raters. CONCLUSION: This study demonstrates good inter-rater reliability of MRI SAP angle measurement among clinicians for use in the modified CTFESI approach.