Fracture depth and delayed contour deformity in frontal sinus anterior wall fracture

The choice to manage isolated frontal sinus anterior wall fractures without the involvement of nasofrontal outflow tract is mainly based on aesthetic concern and depends largely on surgeons' preferences. Minimally depressed anterior wall fractures can be monitored by observation only with little risk of long-term morbidity and contour deformity. The purposes of this study were to evaluate the course of a nonoperated depressed frontal sinus anterior wall fracture and to identify the cutoff value of anterior wall displacement requiring surgical correction.

A retrospective chart review of 51 nonoperated isolated frontal sinus anterior wall fractures was performed. The depth and area of each fracture were measured by computed tomographic scans. Medical records were carefully reviewed to identify the delayed complications or contour changes.

The mean fracture depth and size were 3.9 mm and 352 mm(2), respectively. Patients who had a fracture depth of 4 mm or less did not develop late depressive contour changes of the skin. However, 7 patients who each had a fracture depth of more than 4 mm developed mild contour changes during the months of follow-up. The delayed contour change was associated with fracture depth (P < 0.01), but the fracture area was not considered as an independent factor for delayed contour deformity (P > 0.05).

The presence of depressive contour changes on the skin is an indication for surgical correction of the frontal sinus fracture. Mildly displaced isolated frontal sinus anterior wall fractures can be observed if the fracture depression is less than 4 mm.