Introduction: Cervical Spondylotic Myelopathy (CSM) is a major cause of disability in adults. To date magnetic resonance imaging (MRI) has not been shown to be a prognostic tool in CSM. This study looks at the baseline MRI indicators as predictors of preoperative patient status and postoperative neurological recovery
Methods: A prospective observational study (n=57) enrolling patients with CSM was conducted. MRI scans, Japanese Orthopedic Association (mJOA), recovery rate (RR), Nurick Grade, SF-36, Neck Disability Index (NDI), 30m walk test (cadence (Wc)) and time (Wt), grip strength and Berg Balance Scale (BBS) were administered at baseline and 1 year after surgery.Preoperative and 1 year postoperative measures were compared with univariate and multivariate analysis.
Results: Low T1 signal change on preoperative MRI was associated with a lower mJOA (P=0.003), higher Nurick Grade (P=0.0298), decreased grip strength (P=0.0152), impaired Wt (P=0.0001) and Wc ( P=0.0001) and poor BBS (P=0.0005) at baseline. The presence of focal high T2 signal resulted in lower mJOA scores and higher Nurick Grades as compared with diffuse T2 (P=0.0035 P=0.0079) or no T2 signal (P=0.068 and P=0.0122). In patients where the preoperative MRI showed segmentation of T2 signal, there was a significant increase in Wt and Wc and BBS (P=0.0266; P= 0.0167; P= 0.0042). Preoperative T1 signal was associated with lower postoperative grip strength (P=0.026), greater Wt (P=0.036) and Wc (P=0.009). The presence of preoperative focal T2 signal had a significant association with poorer postoperative Wt (P=0.022) and Wc (P=0.022) and Nurick scores (P=0.023). Preoperative MCC was negatively correlated with the postoperative SF-36 mental sore (P=0.013).
Conclusions: MRI signal changes are predictive of baseline neurological status and extent of postoperative recovery. MRI indicators of poor preoperative baseline status include presence of low T1 signal, presence of focal T2 signal and segmentation of T2 signal.
Patient Care: MRI imaging can be used for predicting outcome and recovery post surgical decompression.
Learning Objectives: To inform clinicians of the potential benefits of MRI imaging in determining outcome after decompressive surgery to treat CSM.