spinal myelopathycervical myelopathycervical spondylosis and myelopathycervical compressive myelopathycervical stenosis with myelopathyspinal cord myelopathysevere cervical myelopathyhoffman sign cervical myelopathycervical disc myelopathycervical spinal cord compressionspinal cord compression myelopathycervical cord myelopathy