Extent of Disc Degeneration after Single-Level Cervical Anterior Microforaminotomy Analyzed with Long-Term Radiological Data

OBJECTIVE: To prove the extents and details of cervical degeneration after anterior microforaminotomy (AMF) with 6-years follow-up. METHODS: A retrospective study of 24 patients, underwent single-level AMF, was performed. Clinical and radiologic data were analyzed with office charts, questionaires, and picture achieving and communication system images. RESULTS: According to Odom's criteria, 91.6% achieved favorable outcome. The mean visual analog scale score was improved from 8.6 to 3, and the mean neck disability index was improved from 27.9 to 7.3 (p<0.01). Eighteen cases (75%) showed disc height (DH) decrease. The disc invasion was correlated with DH decrease (p<0.05). The disc height decrease correlated with static, dynamic changes of shell angle and spur formation (p<0.05). Any radiological parameters did not affect the clinical outcome. CONCLUSION: AMF is an effective technique for treating unilateral cervical radiculopathy. It showed excellent surgical outcomes even in long-term follow-ups. However, a decrease in DH occurred in a considerable number of patients. Disc invasion during surgery may be the trigger of sequential degeneration.