[EFFECTIVENESS OF ANTERIOR CERVICAL PLATE FIXATION FOR UNSTABLE Hangman FRACTURE].

OBJECTIVE: To explore the effectiveness of anterior cervical plate internal fixation in the treatment of unstable Hangman fracture.

METHODS: Between May 2006 and May 2010, 42 patients with unstable Hangman fracture were treated by anterior cervical plate internal fixation. There were 30 males and 12 females with an average age of 36.5 years (range, 22-64 years). According to the Levine-Edwards classification, 25 cases were rated as type II, 15 cases as type II A, and 2 cases as type III. Eight patients had spinal cord injury. The average interval between injury and operation was 5 days (range, 3-14 days). The X-ray, CT, and MRI were done pre- and post-operatively to evaluate the cervical physiological curvature, the intervertebral disc height of C2, 3, the fracture-healing, and bone fusion. The effectiveness was evaluated using visual analogue scale (VAS) for occipitocervical pain, Neck Disability Index (NDI) for cervical spine function, and the Japanese Orthopaedic Association (JOA) score for neurological functional recovery.

RESULTS: All incisions healed by first intention. No neurological deterioration or internal fixation failure was observed. All of the patients were followed up 2-5 years (mean, 3.5 years). The complications were dysdipsia in 3 cases and dysphagia in 4 cases, which alleviated spontaneously after 1 week. All the patients were almost free from occipitocervical pain and the limited cervical spine motion. Neurological function was improved in 8 cases of spinal cord injury, and complete decompression was observed in 6 cases who had spinal cord compression. The bone fusion was observed at 6.5 months on average (range, 6-8 months); the mean fracture-healing time was 10.5 months (range, 9-12 months). The VAS, NDI, and JOA scores were significantly improved at 3 months after operation and last follow-up when compared with preoperative scores (P < 0.05), significant improvement scores were achieved at last follow-up when compared with the scores at 3 months (P < 0.05). The intervertebral disc height of C2, 3, the reconstructed curvature and stability of the cervical spine, and the spine movement were good.

CONCLUSION: The method of anterior cervical plate internal fixation can achieve satisfactory reduction and fusion, less complications, negligible impact on the cervical movement. So it is an ideal method to treat unstable Hangman fracture.