Bony/Cartilaginous Mismatch: A Radiologic Investigation into the Cause of Tension Nose Deformity.

Abstract

Tension nose deformity is believed to be caused by an "oversized" septal quadrangular cartilage. Prior studies have shown that quadrangular cartilage size is relatively consistent in populations. The authors hypothesize that the tension nose deformity is actually caused by an external extrusion of a normal sized septal cartilage from an undersized bony septal encasement. A retrospective case-control study of sagittal computed tomographic scans was conducted, measuring the perimeter and surface area of the quadrangular cartilage and bony septal aperture in tension nose cases and controls. Statistical analysis was performed. Of 23 patients enrolled in the study, 12 patients were sorted into the tension nose group, and 11 patients were considered controls. Both groups had similar perimeter and surface area of their quadrangular cartilage, without statistical difference between the two groups. However, the tension nose group had a statistically significant reduction in bony septal aperture perimeter compared with controls (p < 0.01) and a larger externally extruded septum compared with their internal septal size. They also had a substantially higher rate of septal deviation than controls. The results of this study suggest that a mismatch between a small bony septal aperture and a normal sized septal quadrangular cartilage may be responsible for caudal, upper lip, and dorsal fullness seen with the tension nose deformity caused by external extrusion of cartilage. Septal deviation may co-occur as a buckling phenomenon in a limited bony space. Surgical strategies to match the entire quadrangular cartilage size to the bony framework are suggested. Risk, III.