Radiology reports do not accurately portray the severity of cervical neuroforaminal stenosis

Introduction: Radiology reports of cervical spine MRI are often reviewed to assess the degree of neuroforaminal stenosis. However, research looking at the association between these reports and objective MRI findings as well as clinical symptoms is lacking. Our objectives were to (1) To compare cervical MRI radiology reports to a validated grading system for cervical foraminal stenosis and (2) to evaluate if severity of cervical neuroforaminal stenosis on MRI correlates to motor weakness or patient-reported outcomes.

Methods: We retrospectively identified all adult patients undergoing primary 1- or 2- level ACDF at a single academic center for an indication of cervical radiculopathy. Preoperative MRI was assessed for neuroforaminal stenosis severity using the grading system described by Kim et al. for each level of fusion as well as adjacent levels. Neuroforaminal stenosis severity was recorded from diagnostic radiologist MRI reports. Motor weakness was defined as exam grade < 4/5 on final preoperative encounter. Regression analysis was conducted to evaluate whether the degree of foraminal stenosis by either classification was related to PROM severity.

Results: 283 patients were included in the study and 998 total levels were assessed. There were significant differences between the MRI grading system and assessment by radiology (p < 0.001). In levels with moderate stenosis, 28.9% were classified as having no stenosis by radiology. In levels with severe stenosis, 29.7% were classified as having mild-moderate stenosis or less. Motor weakness was found similarly often in levels of moderate or severe stenosis (6.9% and 9.2%, respectively). On regression analysis, no associations were found between baseline PROMs and stenosis severity assessed by radiologist or MRI grading system.

Conclusion : Radiology reports on the severity of cervical neuroforaminal stenosis are not consistent with a validated MRI grading system and these reports may be inappropriate when used for clinical decision making.