[Treatment of thoracolumbar burst fractures by posterior laminotomy decompression and bone grafting via injured vertebrae].

Objective: To study the effectiveness of posterior laminotomy decompression and bone grafting via the injured vertebrae for treatment of thoracolumbar burst fractures.
Methods: Between November 2010 and November 2012, 58 patients with thoracolumbar burst fractures were treated by posterior fixation combined with posterior laminotomy decompression and intervertebral bone graft in the injured vertebrae. There were 40 males and 18 females with a mean age of 48 years (range, 25-58 years). According to Denis classification, 58 cases had burst fractures (Denis type B); based on neurological classification of spinal cord injury by American Spinal Injury Association (ASIA) classifications, 5 cases were rated as grade A, 18 cases as grade B, 20 cases as grade C, 14 cases as grade D, and 1 case as grade E. Based on thoracolumbar burst fractures CT classifications there were 5 cases of type A, 20 cases of type B1, 10 cases of type B2, and 23 cases of type C. The time between injury and operation was 10 hours to 9 days (mean, 7.2 days). The CT was taken to measure the space occupying of vertebral canal. The X-ray film was taken to measure the relative height of fractured vertebrae for evaluating the vertebral height restoration, Cobb angle for evaluating the correction of kyphosis, and ASIA classification was conducted to evaluate the function recovery of the spinal cord.
Results: The operations were performed successfully, and incisions healed primarily. All the patients were followed up 12-18 months (mean, 15 months). CT showed good bone graft healing except partial absorption of vertebral body grafted bone; no loosening or breakage of screws and rods occurred. The stenosis rates of fractured vertebral canale were 47.56% ± 14.61% at preoperation and 1.26% ± 0.62% at 1 year after operation, showing significant difference (t = 24.46, P = 0.00). The Cobb angles were (16.98 ± 3.67)° at preoperation, (3.42 ± 1.45)° at 1 week after operation, (3.82 ± 1.60)° at 1 year after operation, and (4.84 ± 1.70)° at 3 months after removal of internal fixation, showing significant differences between at pre- and post-operation (P < 0.05). The relative heights of fractured vertebrae were 57.10% ± 6.52% at preoperation, 96.26% ± 1.94% at 1 week after operation, 96.11% ± 1.97% at 1 year after operation, and 96.03% ± 1.96% at 3 months after removal of internal fixation, showing significant differences between at pre- and post-operation (P < 0.05). At 1 year after operation, the neural function was improved 1-3 grades in 56 cases. Based on ASIA classifications, 1 case was rated as grade A, 4 cases as grade B, 10 cases as grade C, 23 cases as grade D, and 20 cases as grade E.
Conclusion: Treatment of thoracic and lumbar vertebrae burst fractures by posterior laminotomy decompression and bone grafting via the injured vertebrae has satisfactory effectiveness, which can reconstruct vertebral body shape and height with spinal cord decompression and good vertebral healing. It is a kind of effective solution for thoracolumbar burst fracture.