The nasal septum is made up of a deep, fixed and rigid part formed by the ethmoid, vomer and maxillary bones, and a partially superficial and pliable part which is the nasal septum cartilage. The osseous part plays almost no role, if any, in the nasal shape but its alignment is of great functional importance of the airway clearance; the cartilaginous part is close to irrelevant regarding breathing function but is of paramount importance as support of the nasal length and nasal tip and supratip length, rotation and alignment.
The nose is made up of a fixed and rigid part that is called nasal pyramid, although it rather has the shape of a tent or roof, and a pliable mobile part which is the nasal tip, the alae and its annexes. The nasal pyramid is formed by two types of structures or tissues; in the most cephalic or upper part the nasal pyramid is formed by the nasal bones and the ascending process of the maxilla, that is, by bone tissue; the most caudal or lower part of the nasal pyramid is formed by the triangular cartilages or also called quadrangular or lateral or upper lateral, that is, by cartilaginous tissue.
Both halves or walls of the nasal pyramid join and fuse horizontally with each other in the center of the nose to form the dorsum, hump or nasal bridge (misnamed by many people as the septum, which is not part of the nasal dorsum), creating what is called pyramid or bony or osseous or hard dorsum (cephalic or upper), formed by synostosis or fusion between bones, and the cartilaginous middle vault or soft pyramid or dorsum (caudal or lower), formed by synchondrosis or fusion between cartilages. In turn, the nasal dorsum is joined and merged by its lower or posterior face with the nasal septum, nasal septum which also, in turn, consists of a cephalic or upper bony part and a caudal or lower cartilaginous part, corresponding the bony septum to the fusion with the cephalic or upper or bony dorsum and the cartilaginous septum to the fusion with the caudal or lower or cartilaginous dorsum, forming a tripod in which the lateral legs are the nasal wall and the central leg the nasal septum.
A septum misaligned at its deep bony part will likely produce breathing turbulences, difficulties or frank obstruction, but no nasal deformities; a misaligned cartilaginous septum is unlikely to impair the nasal function but will doubtless distort the shape and position of the nasal tip and its annexes.
The nasal septum is treated by means of a group of surgical maneuvers named in general as septoplasty, intervention indicated for either functional or aesthetic reasons depending on each particular situation.