Fig. 2From: Neutral hip position for the oblique lumbar interbody fusion (OLIF) approach increases the retroperitoneal oblique corridorDemonstration of manually delineated of the left psoas cross-sectional area (line), the anterior 1/3 of the left psoas muscle (two-headed arrow) and the posterior 1/3 of the left psoas muscle (dotted two-headed arrow)Back to article page