Thank you for the opportunity to respond to the comments by Sussman regarding our paper.

Sussman commented that the reason for re-aggravation of the symptoms in this patient was inadequate decompression, and at least C2 should also have been decompressed. However, we do not agree with this comment for two reasons.

First, the spinal canal and space available for the cord in the region cranial to C2 are wider than the region caudal to C3, so that it is very rare to include C2 in the decompression area in patients with cervical spondylotic myelopathy like this patient, although in some patients with ossification of the posterior longitudinal ligament, C2 may be included. On preoperative MRI, there was adequate subarachnoid space in C2, showing that it was not necessary to include C2 in the decompression area. Furthermore, C2 to which the muscles maintaining the cervical lordosis are attached should not be readily decompressed.

Secondly, on MRI performed 2 months after surgery, at which time symptoms were progressing, there was still adequate subarachnoid space in C2, and the intensity change in the spinal cord and cord enlargement were observed mainly in C3/4–C4/5. In addition, the cord was compressed from the anterior direction in C3/4 in spite of a wide posterior subarachnoid space. Therefore, the causative level of the intramedullary lesion may have been located in C3/4, and not at least in C2 or C2/3.

Based on the above, in this case, the focus that aggravated 2 weeks after improvement of the symptoms observed immediately after expansive laminoplasty may have been located in C3/4, and thus, the cause was not exclusion of C2 from the decompression area.