Oblique fissure

In the lung, the oblique fissure (or major fissure) separates the inferior lobe of either lung from the remainder of the lung. (In the right lung, it separates it from the middle and superior lobe; in the left lung it separates it from the superior lobe, as there is no middle lobe in the left lung.)

The oblique fissure extends from the spinous process of T2 (posteriorly) to 6th costal cartilage (anteriorly)