• Japanese Orthopaedic Association Score for Cervical Myelopathy [ Time Frame: 3 months, 6 months, 1 year, 3 years, 5 years and 10 years ] [ Designated as safety issue: No ]
  

• Motor and sensory functions, gait and hand functions, neck pain, change in cervical alignment, spinal cord signal change on MRI, operative time, blood loss, duration of in-patient stay, post-operative complication, re-operation rate. [ Time Frame: 3 months, 6 months, 1 year, 3 years, 5 years and 10 years ] [ Designated as safety issue: No ]
  

Cervical spondylotic myelopathy (CSM) is a syndrome consisting of symptoms and signs of cervical spinal cord compression caused by chronic degenerative changes of the cervical spine. CSM is the most serious and disabling condition of cervical spondylosis. Natural history studies showed that most of the CSM patients have a progressive deterioration course and no spontaneous regression occurs. It is suggested that the patients with moderate to severe CSM should be operated as early as possible before neurological deficits are too pronounced.

Although there are many options available for the surgical treatment of cervical spondylotic myelopathy, the choice of surgical approach for CSM is still a controversial issue. Most of the surgeons select the surgical approach based on the number of levels involved and the alignment of the spine. Anterior procedure is generally recommended for patients with compression of less than 3 levels or in patients with kyphotic alignment, while posterior decompression is suggested for three or more levels of compression. Retrospective clinical study however has shown that both anterior and posterior surgeries could produce comparable results. There is no scientific data based on randomized, prospective clinical studies comparing the various surgical alternatives. The existing information does not clearly favor any one single approach or operative option. Since anterior and posterior surgeries carries different risks, it is important to identify the most appropriate surgical procedure that is supported by evidence rather than just by surgeons preference.

The objective of this study is to compare the long-term clinical outcome of anterior approach versus posterior approach in the treatment of cervical myelopathy caused by degenerative disease of the cervical spine.