Anatomical assessment of the risk of sympathetic nerve injury in oblique lateral lumbar interbody fusion

Objective To assess the risk of sympathetic nerve injury in oblique lumbar interbody fusion (OLIF) in different lumbar spine segments based on anatomical study. Methods Twenty-four healthy adult volunteers (12 male and female) were selected and routine lumbar spine scanning was performed with MAG MAGOMOM Verio 3.0 T. The anatomical structures of left lumbar sympathetic trunk, abdominal aorta and left psoas muscle were identified on T2 images of L2, 3, L3, 4, L4, 5 intervertebral space. And the anatomical parameters of the OLIF operation approach and the anatomical parameters of the left sympathetic trunk and adjacent structures were measured. The t-test was used to compare the parameters between the different sexes. The comparison of the data between the different segments was performed by the least significant difference (LSD) single factor analysis of variance. Results From the L2, 3 to L4, 5 segments, the anatomical parameters of the OLIF operation approach and the anatomical parameters of the left sympathetic trunk and the adjacent structures showed regular changes. The distances between the anterior margin of the left psoas muscle and the abdominal aorta from L2, 3 to L4, 5 were 13.65±4.10 mm to 9.42 ± 4.00 mm in adult healthy male individuals, and 13.89±3.18 mm to 8.38 ± 3.33 mm in female individuals, showing a significant downward trend. The distances between the left sympathetic trunk and the abdominal aorta from L2, 3 to L4, 5 were 10.76±3.89 mm to 6.68±3.39 mm in adult healthy male individuals, and 11.52±3.02 mm to 6.12±2.95 mm in female individuals, also showing a significant downward trend. There were significant differences in the operation area of OLIF surgery between different segments. The operation area of OLIF surgery was relatively large in L2, 3 segment, and the risk of sympathetic nerve injury was relatively small. The left lumbar sympathetic trunk in the L3, 4 intervertebral space was walking front and inside, and there was a greater risk of injury in the OLIF surgery. Conclusion The left lumbar sympathetic trunk located in or close to OLIF surgery operation field in L2-L5 segments. There was a certain risk of sympathetic nerve injury in OLIF surgery, and the risk of sympathetic nerve injury was different in L2, 3, L3, 4, L4, 5 segments. Key words: Lumbar vertebrae; Spinal fusion; Sympathetic Nervous System; Anatomy, regional