A cadaveric study showing the OLIF corridor dimensions after retraction of the abdominal great arteries and psoas major.

The aim of this study is to assess the oblique lateral interbody fusion (OLIF) corridor dimensions when the abdominal great arteries (the abdominal aorta or common iliac arteries) and psoas major are retracted. Twenty embalmed cadaveric specimens were dissected. The widths of the OLIF operative corridor at L1-2, L2-3, L3-4, and L4-5 were measured with the psoas major and abdominal great arteries in static state, with psoas retraction, and with mild retraction of the abdominal great arteries. The retractable distances of the psoas major and the abdominal great arteries at each lumbar segment were compared. In the static state, the operative corridor gradually narrowed from L1-2 to L4-5, but there was no significant difference in its width between segments (p > 0.05). There was no significant difference in the corridor width between segments after retraction of the psoas major or the abdominal great arteries (p > 0.05). However, retraction of either the psoas major or the abdominal great arteries made the corridor at the L1-5 segments significantly wider than those in the static state (p < 0.05), particularly at L4-5, and the retractable distance of the psoas major was significantly greater (p < 0.05). The cadaveric model demonstrated the use of abdominal great arteries retraction in principle. The OLIF operative corridor could be widened to some extent by retracting the abdominal great arteries, and widened further by retracting the psoas major.