Nasal cartilages

The nasal cartilages are a group of hyaline cartilage structures that form the framework of the lower two-thirds of the nose, providing shape, support, and flexibility to the external nasal structure. They articulate superiorly with the nasal bones and contribute to the structural integrity of the nasal airway.

Components of the Nasal Cartilages

The nasal cartilages are divided into the following major structures:

• Upper lateral cartilages (lateral nasal cartilages): These are paired, triangular cartilages that attach superiorly to the undersurface of the nasal bones and medially to the dorsal septum. They form the middle vault of the nose and play a critical role in maintaining the internal nasal valve, which is the narrowest segment of the nasal airway.

• Lower lateral cartilages (alar cartilages or greater alar cartilages): These are paired cartilages that define the shape of the nasal tip and nostrils. Each lower lateral cartilage has three crura:

  • Medial crus forms the columella

  • Middle (intermediate) crus contributes to the nasal tip lobule

  • Lateral crus provides support to the alar rim and nasal sidewall

• Septal cartilage (quadrangular cartilage): A flat, roughly quadrilateral plate that forms the anterior portion of the nasal septum. It articulates posteriorly with the perpendicular plate of the ethmoid bone and inferiorly with the vomer and the maxillary crest.

• Lesser alar cartilages (sesamoid cartilages): Small, variable cartilaginous pieces found within the fibrous tissue between the upper and lower lateral cartilages and posterolateral to the lower lateral cartilages. They provide minor structural support to the alar region.

Functional Significance

The nasal cartilages are essential for maintaining nasal airway patency, particularly at the internal and external nasal valves. They also determine the aesthetic appearance of the nose and are the primary structures manipulated during rhinoplasty. The scroll area, where the cephalic margin of the lower lateral cartilage overlaps the caudal margin of the upper lateral cartilage, is a key anatomical landmark in nasal surgery.

The cartilages are connected to each other and to the surrounding bony structures by fibrous connective tissue, allowing limited mobility while maintaining structural integrity. With aging, the cartilages may weaken, contributing to nasal tip ptosis and airway compromise.