Objective:To compare the clinical outcomes and complications of oblique lateral interbody fusion combined with bilateral pedicle screw fixation through intermuscular approach and posterior interbody fusion combined with bilateral pedicle screw fixation through intermuscular approach by channel for lumbar spinal stenosis.Methods:A retrospective study was conducted on 73 patients who underwent surgical treatment for lumbar spinal stenosis from Jun 2015 to Jun 2017, including 33 males and 40 females. The average age was 66.8±7.94 years (from 39-85 years). These diseases occured at L 3/4 in 5 patients and L 4/5 in 68 patients. Random according to the time of admission, 38 cases were treated with oblique lateral interbody fusion combined with bilateral pedicle screw fixation through intermuscular approach (oblique lateral fusion group), and 35 cases with posterior interbody fusion combined with bilateral pedicle screw fixation through intermuscular approach by channel (posterior fusion group). The clinical results, image data and complications were compared between the two groups. Results:All patients in both groups had operation performed smoothly. The operation time was 99±8.96 min in the oblique lateral fusion group and 96.8±9.57 min in the posterior fusion group, and there was no significant difference between the two groups. The intraoperative bleeding in the oblique lateral fusion group 80±24.72 ml was significantly less than that in the posterior fusion group 261±52.87 ml ( t=9.621, P<0.05). No incision infection occurred after surgery. The VAS score of lumbar incision 72h after operation in the oblique lateral fusion group 1.21±0.55 was significantly less than that in the posterior fusion group 1.70±0.86 ( t=3.723, P=0.028). The follow-up period lasted for 12-24 months, averagely 17.5±2.58 months. There was statistically significant difference between preoperative and postoperative in the two groups, whether it was the area of the foraminal canal or the area of the spinal canal. There wboth the foraminal area and the spinal canal area were enlarged. The intervertebral space height in the two groups recovered significantly after surgery, the difference was statistically significant. But the intervertebral space height were partly lost at the last follow-up, and there was significant difference compared with postoperative. During the follow-up, no pedicle screw loosening, displacement, rupture, or anterior and lateral displacement of cage occurred. The fusion rate was 97.1% in the posterior fusion group and 100% in the oblique lateral fusion group. There was no statistical difference between the two groups.In terms of ODI index: the posterior fusion group recovered from 48.6±6.1 preoperative to 10.2±2.2 at the last follow-up, and the oblique lateral fusion group recovered from 49.0±5.7 preoperative to 9.3±1.8 at the last follow-up. There was statistically difference between last follow-up and preoperative in the two groups. The incidence of complications in the posterior fusion group was 22.86%, and the incidence in the oblique lateral fusion group was 23.68%. There was no significant difference between the two groups. Conclusion:Both the two decompression and fusion methods have achieved good clinical results in the treatment of lumbar spinal stenosis, with the advantages of less trauma, good stability, fast recovery, and high fusion rate. Compared with posterior decompression and fusion methods, the advantages of OLIF are more obvious, such as less bleeding,lower risk of nerve injury and good indirect decompression of spinal canal. Therefore, the OLIF technique can be a better choice for surgical treatment of lumbar spinal stenosis.

Objective:To investigate the characteristics and causes of endplate injury in the oblique lateral interbody fusion for the treatment of lumbar diseases, and summarize the precaution of endplate injury.Methods:Thirty-five cases of endplate injury were observed, which were originally treated with oblique lateral interbody fusion with or without pedicle screw fixation from October 2014 to December 2017. There were 7 males and 28 females, and the age ranged from 51 to 78 years old (averagely 62.8±8.13 years). There were 2 cases of lumbar disc degeneration, 10 cases of lumbar canal stenosis, 17 cases of lumbar degenerative spondylolisthesis, 2 cases of lumbar spondylolysis with or without spondylolisthesis, and 4 cases of lumbar degenerative scoliosis. Lesion sites contained L 3,4 in 2 cases, L 4,5 in 21 cases, L 2-4 in 3 cases, L 3-5 in 4 cases, L 2-5 in 3 cases and L 1-5 in 2 cases. Preoperative bone mineral density examination revealed there were 7 cases of T>-1 SD, 24 cases of -2.5 SD