[Anterior single segmental decompression and fusion to treat lumbar burst fracture]

To explore an improved surgical approach to the superior posterior partial resection of the fractured vertebral body followed by the single segmental fusion to treat lumbar burst fracture and to evaluate its preliminary clinical application.

From June to October 2006, 4 patients (2 males, 2 females; age, 17-39 years ) with Denis B type lumbar burst fracture underwent the superior posterior partial resection of the fractured vertebral body followed by the single segmental fusion. The fracture occurred in 2 patients at L1 and 2 at L2. According to the Frankel scales assessment, before operation, 2 patients were at Grade B and the other 2 at Grade C, and the visual analogue scale (VAS) was 7.00 +/- 0.82. Radiological evaluation was performed, which revealed the kyphosis Cobb angel of 22.94 +/- 11.21 degrees, the adjacent superior and the inferior intervertebal disc heights of 12.78 +/- 1.52 mm and 11.68 +/- 1.04 mm, respectively, and the vertebral canal sagittal diameter of 9.56 +/- 2.27 mm on the computer tomography (CT) scan. The neurological and the radiological evaluations were also made immediately and 3 months after operation.

The anterior single segmental decompression and fusion operations were performed successfully in all the patients. The average operating time was 166 +/- 29 min and the average amount of blood loss was 395 +/- 54 ml. The Frankel scales assessment showed that at the time immediately after operation, one of the 2 Grade B patients had an improvement to Grade C, but the other patient had no improvement. One of the 2 Grade C patients had an improvement to Grade D, but the other patient had no improvement. Three months after operation, the 2 Grade B patients had an improvement to Grade C. The 2 grade C patients had an improvement to Grade D or E. The VAS score was significantly decreased to 3.50 +/- 1.29 after operation and to 1.25 +/- 0.50 3 months later (P < 0.05). The vertebral canal sagittal diameter was significantly increased to 19.76 +/- 3.82 mm (P < 0.01), but it was maintained to 19.27 + 3.41 mm 3 months later, with no significant difference( P > 0.05). The patients' kyphosis Cobb angle was significantly improved to 8.71 +/- 5.41 degrees (P < 0.05) , but it was maintained to 9.52 +/- 5. 66 degrees 3 months later, with no significant difference (P > 0.05). The heights of the adjacent discs remained unchanged. No complication was observed during and after operation, and the radiological and the CT scanning evaluations 3 months later showed no failure of the internal fixation.

The superior and posterior partial resection of the fractured vertebral body followed by the single segmental fusion can effectively decompress the vertebral canal and maintain the spine stability in treatment of the Denis B type fracture though the long-term effectiveness requires a further follow-up.