Analysis of Radiologic Factors Affecting Longterm Surgical Results of Anterior Cervical Fusion Patients.

Choe, Il Seung; Seo, Dae Hee; Park, Sung Choon; Chae, Euy Byung; Choi, Sun Wook; Song, Kwan Young; Kang, Dong Soo

Original Article

Journal of Korean Neurosurgical Society 2001;30(2): 194-200.

Il Seung Choe, Dae Hee Seo, Sung Choon Park, Euy Byung Chae, Sun Wook Choi, Kwan Young Song, Dong Soo Kang

¹Department of Neurosurgery, College of Medicine, Kwandong University, Myongji Hospital, Kyunggi, Korea.
²Department of Neurosurgery, Kangnam General Hospital, Public Corporation, Seoul, Korea.

ABSTRACT

OBJECTIVE
Anterior cervical discectomy and fusion is accepted as appropriate surgical intervention for disease processes of the ventral cervical spine. In some cases, however, improvement of symptom following operation develop myelopathy or rhizopathy at longterm follow-up. We studied to clarify the correlation between clinical results and plain radiologic findings at long term follow-up.
METHODS
A total of 86 patients who underwent anterior cervical discectomy and fusion were grouped into deteriorated and good recovery group. These two groups were compared in lateral functional roentgenograms on the cervical kyphosis and disc height at fused level, sagittal plane rotation and dynamic sagittal canal diameter at adjacent level.
RESULTS
The presence of cervical kyphosis and disc height at fused level do not correlate with long term follow-up results. Sagittal plane rotation of more than 20 degrees were identified in 36% of the cases in deteriorated group, whereas the same findings were identified in 15% of the cases in good group. Sagittal diameter of less than 12mm were identified in 48% of the cases in deteriorated group, whereas the same finding were identified in 8% of the cases in good group. Preoperatively, sagittal plane rotation of more than 20 degrees at adjacent level were identified in 28% of the cases in deteriorated group, whereas the same findings were identified in 13% of the cases in good group. Preoperatively sagittal diameter of less than 12mm at adjacent level were identified in 40% of the cases in deteriorated group, whereas the same finding were identified in 7% of the cases in good group.
CONCLUSION
Large sagittal plane rotation and small dynamic sagittal diameter at adjacent level were factors that might be associated with later clinical deterioration after cervical anterior fusion.

Key Words: Anterior cervical fusion; Dynamic sagittal stenosis; Sagittal plane rotation