[Anterior revision surgery for the treatment of cervical spondylosis after anterior decompression and titanium mesh fusion].

Objective: To analyze the reasons why anterior decompression and titanium mesh fusion for cervical spondylosis always show poor therapeutic effects, and to investigate the clinical effects of anterior revision surgery in these patients.

Methods: From January 2004 to December 2011, 16 patients underwent anterior decompression and titanium mesh fusion for cervical myelopathy were treated with anterior revision surgery. There were 7 males and 9 females with an average age of 61 years old (ranged from 46 to 75 years), including 11 cases with cervical spondylotic myelopathy, 2 cases with nerve root cervical spondylosis and 3 cases with mixed type cervical spondylosis. Average duration from the first operation to reoperation was 7 years(ranged from 4 to 12 years). In the first operation, titanium mesh segment located in C3-C5 (2 cases), C4-C6 (8 cases), C4-C7 (2 cases), C5-C7 (4 cases), and one of them, titanium mesh implantation in C4 and C5,6 intervertebral disk removal and cage fusion. After the first operation, symptom of 13 patients recurred after improvement or disappearance, 2 patients did not show obvious improvement, and 1 patient aggravated. Cervical spine radiography, CT scan and MRI were performed in all patients before re-operation. There were 12 patients with compression of the spinal cord or nerve root caused by degenerative changes in adjacent segments of fusion segments, 4 cases in upper segments, and 8 cases in lower segments; 3 patients with compression of the spinal cord or nerve root caused by vertebral posterior osteophyte of decompressed segments; 1 patient with compression of the spinal cord caused by incomplete anterior decompression. JOA, NDI and Odom classification were used to assess the clinical effects.

Results: All anterior revision surgery were successful with a mean time of 110 min (80 to 150 min) and mean bleeding of 160 ml (30 to 200 ml). There was 30 ml clear drainage fluid in 1 patient suspected of cerebrospinal fluid leakage. But the 2nd day after operation, the tube was removed and the drainage opening was sutured, and the suture incision healed in grade A after 10 days. Other patients had no complications such as dysdipsia, hoarseness, and laryngeal edema, etc. All patients were followed up for 12 to 28 months with an average of 16 months. Two months after operation and at last follow-up, JOA scores and ODI index had obviously improved than preoperation (P < 0.01), and there was significant difference between postoperative 2 months and last follow-up (P < 0.01). At the final follow-up, improvement rate of JOA was (72.9 +/- 0.2)%. According to the standard of Odom, 12 cases got excellent results, 3 good, 1 fair.

Conclusion: After surgery of cervical decompression and bone graft fusion with titanium mesh, the patients need re-operation because of incomplete decompression, degenerative changes in adjacent segments or newly formed compression factors, and complications caused by implants. Anterior revision surgery can obtain good clinical effects.