Abstract: Objective To evaluate the value and efficacy of self-anchored lateral lumbar interbody fusion (SA-LLIF), avoid posterior internal fixation and simplify the surgical procedure. Methods Eleven patients with lumbar degenerative disease treated in our hospital from March to June 2019 were enrolled in this study, including 3 males and 8 females (aged 55-76 years). All patients had low back pain and leg pain, which aggravated when standing and moving and alleviated or disappeared when staying in bed. The imaging results revealed that there were 7 cases of lumbar instability, 4 cases of spondylolisthesis (grade Ⅰin 3 cases, grade Ⅱ in 1 case), 2 of them with scoliosis and 2 with osteoporosis. The fusion level included L 2-3 in 1 case, L3-4 in 4 cases, L4-5 in 4 cases, L2-4 in 1 case and L3-5 in 1 case. Zero-profile self-anchored cage was used for lateral lumbar interbody fusion to avoid posterior internal fixation. After general anesthesia, the patient was in right decubitus position. The anterior edge of psoas major muscle was exposed through left small incision and extraperitoneal approach, the left side of the responsible intervertebral space was exposed by properly retracted psoas major muscle. After the intervertebral space was prepared, a suitable size of fusion cage filled with allograft was implanted. Two anchoring plates were inserted into the cage and the caudal and cephalic vertebral body, and the fusion cage was locked. The clinical efficacy was evaluated by visual analogue scale (VAS) and Oswestry dysfunction index (ODI). The lumbar lordosis (LL), disc height (DH), slippage rate (S) and sinking were evaluated by X-ray. Results The operation was performed successfully in all the 11 patients. The operation time was 65-110 minutes, with an average of (78.0±21.5) minutes. The intraoperative blood loss was 15-60 mL, with an average of (35.0 ± 23.2) mL. No severe complication such as nerve or blood vessel injury was occurred. The patients were encouraged to ambulated next day after operation with soft brace. The VAS score was significantly decreased from preoperative (6.2±0.8) to (1.70±0.5) after surgery, and ODI score was significantly decreased from (47.8%±14.9%) to (11.2%±3.2%). Postoperative X-ray showed that the spine alignment recovered satisfactorily, the LL recovered from (36.4°±10.2°) to (48.0°±10.7°), DH recovered from (8.3±2.5) mm to (13.3±3.3) mm, and the S recovered from (26.7%±4.4%) to (10.3%±5.3%). No cage displacement was found during follow-up, and sinking of cage was found in only one obesity woman. Conclusion SA-LLIF can provide immediate stability with good results, avoid posterior internal fixation.

Key words: lumbar vertebrae, intervertebral disc degeneration, spinal fusion, surgical procedure, minimally invasive, lateral approach