Although anterior spinal decompression and fusion (ASF) is established for cervical myelopathy, some cases undergo re-operation because of disorders in the adjacent segment for a long-term. In our institution, twenty-five cases underwent laminoplasty for disorders in the adjacent segment after ASF. We evaluated risk factors by comparing re-operation cases with a control well natching in terns of age, sex, and postoperative terms. We examined diameter of spinal canal, stenosis of the adjacent segment to fusion performed in the first operation, pre-operative Japanese Orthopaedic Association score for cervical myelopathy, and preoperative cervical spine sagital alignment. Only stenosis of the adjacent segment to fusion performed in the first operation showed significant differences between the two groups. There were no significant differences for the other itens. Although ASF poses a high risk of re-operation compared with posterior surgery in the first time operation, ASF has some merits. Posterior surgery is not always considered superior to anterior surgery, however, only in terms of lower rate of re-operation.
