The Imaging Features And Prognostic Factors Of Mono-segmental Cervical Spondylotic Myelopathy With Lower Cervical Instability

Objective: To investigate the clinical effects of cervical spondylosis myelopathy which has different types of increased spinal cord signal intensity on T2-weighted images after anterior cervical decompression and fusion(ACDF)Methods: From March 1998 to September 2012,121 cases and imageologic date of CSM after ACDF were retrospectively analysed.Among them,the course of disease were 3 months to 9 years(average 24.9±0.3 months).All the patients examined cervical MRI before the operation.The surgical improvement rate were assessed according to the Japanese Orthopedic Association Sore.We adopted factorial design(two factors and two levels)to statistial analyze the date.The two factors were edge condition of increased signal intensity and the location of increased signal intensity.The two factors were divided into two levels alone.All the patienta were divided into four groups.The A1B1 group was increased signal intensity located at the center of spion and which edge was ambiguous. The A1B2 group was increased signal intensity located at the center of spion and which edge was clear.The A2B1 group was increased signal intensity located at the center of spion and the white matter of the spinal cord,with ambiguous edge.The A2B2 group was increased signal intensity located at the center of spion and the white matter of the spinal cord,with clear edge.To compare the relationship between different types of increased signal spinal intensity with the improvement rate,and the interaction among these factors.results All the patients were followed up.The JOA scores and improvement rate among these groups had significant difference(P<0.05).The post operative improvement rate of A1B1 group was the best,and the A2B2 group was the last.The post operative improvement rate of ambiguous edge was better than clear edge and central spine was better than central with the white matter of the spinal cord.conclusions Factor A and factor B were two independent influenting factors,but all of them were correlation with the prognosis of CSM patients.When the increased signal spinal intensity located at the central and the white matter of the spinal cord,with clear edge,it indicated that the prognosis of patients were relatively not better.Results: All the patients were followed up.The JOA scores and improvement rate among these groups had significant difference(P<0.05).The post operative improvement rate of A1B1 group was the best,and the A2B2 group was the last.The post operative improvement rate of ambiguous edge was better than clear edge and central spine was better than central with the white matter of the spinal cord.Conclusion: Factor A and factor B were two independent influenting factors,but all of them were correlation with the prognosis of CSM patients.When the increased signal spinal intensity located at the central and the white matter of the spinal cord,with clear edge,it indicated that the prognosis of patients were relatively not better.