Chapter 2. Framework: Cartilaginous Support
The cartilaginous framework of the nose is composed of paired upper and lower lateral cartilages that extend out from the end of the bony pyramid. Each pair of cartilages has a distinctly different shape (Figure 2-1).
Figure 2-1. Nasal cartilages.
The upper lateral cartilages are relatively flat and form the caudal sidewalls of the nasal pyramid. The medial border of each lies against the septum in the midline. The lateral border rests near the piriform aperture within the sidewalls of the nose. Their angle with the midline septum forms the internal nasal valve.
The lower lateral cartilages have a more intricate structure. They are curved strips that bend around the alar rims and function to maintain competence at the external nasal valve (Figure 2-2). Each is composed of three parts, or crura.