The behaviour of nasal septal cartilage in response to trauma.

Hyaline "glassy" cartilage possesses an internal interlocked stress system. This system is designed like a sandwich in which the outer layers hold in the inner layers under a degree of tension. This arrangement gives the cartilage the property of elasticity, allowing the cartilage to revert to its original form following limited deformation. If, however, the outer layer is breached, the system breaks down and the cartilage bends to the opposite side. Fry (1967, 1968, 1974, 1976) demonstrated on human septal and articular cartilage that cartilage does deviate in this manner when scored down one side with a scalpel. He then extrapolates this experimental finding into the clinical sphere to account for the deviated nasal septum. He feels that multiple minor breaches of one side of the outer layer of the septum produce a deviated septum. A challenge of this assumption forms the basis of this paper. Human septal cartilage was traumatised and left to deviate spontaneously in-vitro. If the Fry theory is correct, the cartilaginous septum should deviate. This did not happen and, on the evidence presented in this paper, the Fry theory of the pathogenesis of the deviated nasal septum is refuted.