Figure 1

Crossing patterns of the depressor septi nasi (DSN) and orbicularis oris (OOr) muscles attached to the footplates of the medial crura (fMCs). (A) Type I: Both DSNs (arrowheads) were predominantly attached to the corresponding fMCs, and some of their fibers (arrows) crossed to attach to the fMCs on the contralateral sides as bilateral crossing fibers. (B) Type II: Both DSNs (arrowheads) were predominantly attached to the corresponding fMCs. Some DSN fibers (white arrow) on one side and some OOr fibers (black arrow) on the contralateral side crossed each other to attach to the fMCs as bilateral crossing fibers. (C) Type III: Both DSNs (arrowheads) were predominantly attached to the corresponding fMCs, and some DSN fibers (arrow) on one side crossed to attach to the fMC on the contralateral side as unilateral crossing fibers. Connecting fibers between both DSNs beneath the fMCs were often found in an arched shape in this type. (D) Type IV: The DSNs (arrowheads) were present bilaterally and there were no crossing fibers of the DSN or OOr attached to the fMCs. (E) Type V: The DSN (white arrowheads) on one side and some OOr fibers (black arrowheads) on the contralateral side were predominantly attached to the corresponding fMCs. Some of the DSN (arrows) on one side crossed to attach to the fMC on the contralateral side as unilateral crossing fibers. (F) Type VI: When the DSN was not present, some OOr fibers (arrowheads) ascended to attach to the fMCs instead of the DSNs. DAN depressor alae nasi, SC septal nasal cartilage.