The Caucasian Hump: Radiologic Study of the Osteocartilaginous Vault versus Surface Anatomy. Clinical Implications in Structured and Preservation Rhinoplasty

Overview

The relationship between the bone and cartilage roof of the nose and the characteristics of a nasal hump had not been fully investigated. Measurements were taken from CT scans in the mid line plane in adult Caucasian patients seeking rhinoplasty for a hump between January 2015 and December 2018, and compared against age and sex matched patients not seeking rhinoplasty. Patients with other significant nasal deformities were excluded.

Sections of note

• CT study of 134 Caucasian patients, 67 with a nasal hump; mean age 32.9 years, 69.6 percent female.
• Hump length averaged 17 plus or minus 2.7 mm; height averaged 1.8 mm, range 1.1 to 3.8 mm.
• Hump length correlated with nose length and nasal bone length.
• Hump height correlated with nose length and the angle over the kyphion.
• In 97 percent of patients the hump began below the ethmoidal point.
• In all patients the kyphion lay underneath the hump.
• The hump was not a symmetric structure, and in every patient its peak sat above the septal cartilage.
• The authors conclude the caudal part of the nasal bones contributes to the hump while the posterior ethmoidal plate rarely does.

What it means for a patient

• The bump on a nasal profile is mostly cartilage rather than bone, contrary to the common assumption.
• The authors state the septal cartilage should therefore be the cornerstone of any hump reduction plan.
• The hump was asymmetric in every patient, so lowering it evenly is not straightforward.
• The study covers Caucasian patients only and does not extend to other nasal anatomies.

Why this paper matters

Both hump removal and dorsal preservation depend on knowing which structure creates the profile bump, and that had been assumed rather than measured. This CT study locates it in the septal cartilage. How this maps to which technique gives better results is not tested here.

Terms

• Osteocartilaginous vault: the combined bone and cartilage roof of the nose.
• Nasal hump: the bump on the profile of the bridge.
• Septal cartilage: the cartilage plate forming the central partition of the nose.
• Kyphion: the highest point of the bony profile of the nose.
• Ethmoidal point: a defined landmark on the ethmoid bone at the top of the septum.
• Midsagittal plane: the vertical plane dividing the body into left and right halves.