The feasibility of building the oblique lumbar interbody fusion corridor: A CT image study / 中华骨科杂志

ABSTRACT

Objective To determine the radiographic feasibility of oblique lumbar interbody fusion (OLIF) corridor to treat lumbar disease at each lumbar disc level,including the corridor's numerical value and the influence of diaphragmatic crura and aorta abdominalis.Methods A retrospective CT study was conducted on 110 patients (including 69 males and 41 females,average age 47.95 years,range 16-83 years) that continuously collected and analyzed in the PACS system.The oblique corridor was defined as the area between the left lateral border of the aorta abdominalis(or iliac artery) and the right lateral border of the left psoas.The distances and angles of L1-2,L2-3,L3-4 and L4-5 levels were measured.Whether the change of diaphragmatic crura and aorta abdominalis affected the building of the corridor was also observed.Results The mean distances of oblique corridor to the levels of L1-L5 discs wereL1-2 15.90 mm,L2-3 14.82 mm,L3-4 17.57 mm,L4-5 11.16 mm.At the levels of L1-2 and L3-4,all of the images could build the corridor.But there were only 97.27％ images allowing operation at both L2-3 and L4-5,and the other 3 cases couldn't build the corridor since the aorta abdominalis was very close to psoas,and the distance was almost 0 mm.The max mean distance was 36.79 mm at L3-4 level.The mean angles wereL1-2 36.98°;L2-3 37.76°;L3-4 40.96°;L4-5 37.85°.The significant difference was at L3-4,ranged from 13.09 to 61.93°.The level of the aortic bifurcation was from the lower third of the L3 vertebral body to the middle third of the L5 vertebral body.The levels of left diaphragmatic crura's ending point in the lumbar was divided into four groups1) Group L1 vertebral body levelthe level at L1 vertebral body and above,5 cases (4.55％);Group L1-2 disc to L2 vertebral body levelat L1-2 disc and L2 vertebral body,67 cases (60.91％);Group L2-3 disc to L3 vertebral body levelat L2-3 disc and L3 vertebral body,36 cases (32.72％);Group L3-4 disc to L4 vertebral body levelat L3-4 disc and L4 vertebral body,2 case (1.81％).Conclusion The OLIF corridor can be built successfully at L1-2 and L3-4.However,it may be difficult at L2-3 and L4-5 for some patients due to the aorta abdominalis which is too close to psoas.The angles of L1-L5 levels were similar.While the left diaphragmatic crura was mainly impact the corridor insertion at L1-2 and L2-3.And the level of the aortic bifurcation was mainly located at the upper endplate of L4 to the L4-5 disc (87％).