[Effectiveness of unilateral biportal endoscopy combined with percutaneous pedicle screw fixation in treatment of lumbar burst fractures with neurological symptoms].

OBJECTIVE: To evaluate the effectiveness of spinal canal decompression assisted by unilateral biportal endoscopy (UBE) and percutaneous uniplanar pedicle screw internal fixation in the treatment of lumbar burst fractures with neurological symptoms.

METHODS: Between June 2021 and December 2022, 10 patients with single level lumbar burst fracture with neurological symptoms were treated with spinal canal decompression assisted by UBE and percutaneous uniplanar pedicle screw internal fixation. There were 7 males and 3 females with an average age of 43.1 years (range, 21-57 years). The injured vertebrae located at L 1 in 2 cases, L 2 in 4 cases, L 3 in 3 cases, and L 4 in 1 case. There were 7 cases of AO type A3 fractures and 3 cases of AO type A4 fractures. The total operation time, the time of operation under endoscopy, and complications were recorded. Pre- and post-operative visual analogue scale (VAS) score and American Spinal Injury Association (ASIA) scale (grading A-E corresponding to assigning 1-5 points for statistical analysis) were used to evaluate effectiveness. X-ray film and CT were performed to observe the fracture healing, and the ratio of anterior vertebral body height, Cobb angle, and rate of spinal canal invasion were measured to evaluate the reduction of fracture.

RESULTS: All operations was successfully completed, and the spinal canal decompression and the bone fragment in spinal canal reduction completed under the endoscopy. Total operation time was 119 minutes on average (range, 95-150 minutes), and the time of operation under endoscopy was 46 minutes on average (range, 35-55 minutes). There was no complication such as dural sac, nerve root, or blood vessel injury during operation. All incisions healed by first intention. All patients were followed up 18.7 months on average (range, 10-28 months). The VAS score after operation significantly decreased when compared with that before operation ( P <0.05), and further improved at last follow-up ( P <0.05). The ASIA scale after operation significantly improved when compared with that before operation ( P <0.05), and there was no significant difference ( P >0.05) in the ASIA scale between at 1 week after operation and at last follow-up. The imaging examination showed that the screw position was good and the articular process joint was preserved. During follow-up, there was no loosening, fracture, or fixation failure of the internal fixation. The ratio of anterior vertebral body height and Cobb angle significantly improved, the rate of spinal canal invasion significantly decreased after operation ( P< 0.05), and without significant loss of correction during the follow-up ( P >0.05).

CONCLUSION: Spinal canal decompression assisted by UBE and percutaneous uniplanar pedicle screw fixation is a feasible minimally invasive treatment for lumbar burst fractures with neurological symptoms, which can effectively restore the vertebral body sequence, as well as relieve the compression of spinal canal, and improve the neurological function.