

THE EXTERNAL NOSE 



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FIG. 852. Cartilages of the nose. Side view. 



It may be prolonged backward (especially in children) as a narrow process, the sphenoidal pro- 

 cess, for some distance between the vomer and perpendicular plate of the ethmoid. The septal 

 cartilage does not reach as far as the lowest part of the nasal septum. This is formed by the 

 medial crura of the greater alar cartilages and by the 

 skin; it is freely movable, and hence is termed the 

 septum mobile nasi. 



The lateral cartilage (cartilago nasi lateralis; upper 

 lateral cartilage) is situated below the inferior margin 

 of the nasal bone, and is flattened, and triangular in 

 shape. Its anterior margin is thicker than the pos- 

 terior, and is continuous above with the cartilage of 

 the septum, but separated from it below by a 

 narrow fissure; its superior margin is attached to 

 the nasal bone and the frontal process of the max- 

 illa; its inferior margin is connected by fibrous 

 tissue with the greater alar cartilage. 



The greater alar cartilage (cartilago alaris major; 

 lower lateral cartilage) is a thin, flexible plate, sit- 

 uated immediately below the preceding, and bent 

 upon itself in such a manner as to form the medial 

 and lateral walls of the naris of its own side. The 

 portion which forms the medial wall (cms mediale} 

 is loosely connected with the corresponding portion 

 of the opposite cartilage, the two forming, together 

 with the thickened integument and subjacent tis- 

 sue, the septum mobile nasi. The part which 

 forms the lateral wall (cms laterale) is curved to 

 correspond with the ala of the nose; it is oval and 



flattened, narrow behind, where it is connected with the frontal process of the maxilla by a tough 

 fibrous membrane, in which are found three or four small cartilaginous plates, the lesser alar 

 cartilages (cartilagines alares minores; sesamoid cartilages). Above, it is connected by fibrous 

 tissue to the lateral cartilage and front part of the cartilage of the septum; below, it falls short 

 of the margin of the naris, the ala being completed by fatty and fibrous tissue covered by skin. 

 In front, the greater alar cartilages are separated by a notch which corresponds with the apex 

 of the nose. 



Greater alar 

 cartilage 



Lesser alar 

 cartilages 



FIG. 853. Cartilages of the nose, seen from below. 



FIG. 854. Bones and cartilages of septum of nose. 

 Right side. 



The muscles acting on the external nose have been described in the section on Myology. 



The integument of the dorsum and sides of the nose is thin, and loosely connected with the 

 subjacent parts; but over the tip and alae it is thicker and more firmly adherent, and is furnished 

 with a large number of sebaceous follicles, the orifices of which are usually very distinct. 



The arteries of the external nose are the alar and septal branches of the external maxillary, 

 which supply the alae and septum; the dorsum and sides being supplied from the dorsal nasal 

 branch of the ophthalmic and the infraorbital branch of the internal maxillary. The veins end in 

 the anterior facial and ophthalmic veins. 



The nerves for the muscles of the nose are derived from the facial, while the skin receives 

 branches from the infratrochlear and nasociliary branches of the ophthalmic, and from the infra- 

 orbital of the maxillary. 

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