Inverted-V Deformity: An Anatomic Study.

[BACKGROUND] The inverted-V deformity is an unwanted aesthetic consequence of dorsal hump resection. Despite their attachment to the nasal bones, the upper lateral cartilages (ULCs) can separate from the nasal bones, creating a step-off after cartilaginous dorsal hump removal.

[OBJECTIVES] The mechanism of how the ULCs can separate from the nasal bones despite their attachment was studied to improve understanding of the inverted-V complication and its prevention.

[METHODS] A dorsal hump resection (bony and cartilaginous) was performed on 12 fresh cadavers to observe the effect on the ULCs. As a secondary study, the effect of different preventative maneuvers was investigated.

[RESULTS] Cartilaginous dorsal resection destroys the spreader mechanism of the T-frame and impacts the stabilization of the ULCs, resulting in them becoming free-floating. This causes them to migrate in a posterior, medial, and cranial direction relative to the nasal bones. The dynamic attachment of the ULCs to the nasal bones is key in this mechanism and allows actual separation of the ULCs from the nasal bones to result in the inverted-V deformity. Caudal traction to the ULCs re-tensions these attachments, pulling the ULCs against the nasal bones again.

[CONCLUSIONS] This anatomic dissection study has established that the connection between the nasal dorsum and ULCs is not a static fusion but is dynamic. This attachment can be used in primary rhinoplasty to prevent inverted-V deformity by applying caudal traction to the ULCs when reconstructing the dorsum which will tension the ULCs toward the nasal bones.