Objective: To investigate the surgical method and preliminary clinical result of managing the patient with lumbar burst fracture but not suitable for single-level fixation and fusion surgery with the reservation of the fractured vertebral body and the anterior decompression.
Methods: From September 2007 to December 2008, 11 patients with lumbar burst fracture underwent the removal of the posterior superior corner of the injured vertebral body, the removal of the inferior intervertebral disc adjacent to the injured vertebral body, bone graft fusion, and internal fixation. There were 8 males and 3 females aged 21-48 years old (average 29.4 years old). All the fractures caused by falling from high places. Imaging exams confirmed all the fractures were Denis type B burst fracture. The fracture level was at the L1 in 4 cases, the L2 in 4 cases, the L3 in 2 cases, and the L4 in 1 case. Before operation, the nerve function was graded as grade B in 4 cases, grade C in 3 cases, and grade D in 4 cases according to Frankel scales; the visual analogue scale (VAS) was (7.30 +/- 0.98) points; lateral X-ray films displayed the kyphosis Cobb angel was (24.94 +/- 12.21) degrees; the adjacent superior and inferior intervertebral disc height was (12.78 +/- 1.52) mm and (11.68 +/- 1.04) mm, respectively; CT scan showed the vertebral canal sagittal diameter was (9.56 +/- 2.27) mm; CT three-dimensional reconstruction revealed that the intact part of the injured vertebra was less than 50% vertebra body height and the fracture line crossed the pedicle. The time from injury to operation was 3-11 days (average 4.8 days). The neurological and radiological evaluations were carried out immediately and 3 months after operation, respectively, and compared with the condition before operation.
Results: All the patients successfully underwent the surgery. The wound all healed by first intention. All the patients were followed up for 6-18 months (average 14 months). All the patients had a certain degree of nerve function recovery. The Frankel scales in all the patients were increased by 1-2 grade immediately and 3 months after operation. The VAS score was (2.80 +/- 1.49) points immediately after operation and (1.54 +/- 0.48) points 3 months after operation, suggesting there were significant differences among three time points (P < 0.05). The vertebral canal sagittal diameter was significantly enlarged to (18.98 +/- 4.82) mm immediately after operation and was (19.07 +/- 4.37) mm 3 months after operation. The Cobb angle was (7.78 +/- 4.52) degrees immediately after operation and (8.23 +/- 3.57) degrees 3 months after operation. There were significant differences between before and after operation (P < 0.05). For the adjacent superior and inferior intervertebral disc height, there was no significant difference when the value immediately or 3 months after operation was compared with that of before operation (P > 0.05). X-ray films and CT scan 3 months after operation showed good internal fixation without the occurrence of loosing and displacement.
Conclusion: For the treatment of lumbar burst fracture, the method of reserving the injured vertebral body and anterior decompression can decompress the vertebral canal and shorten the duration for bony fusion.