Facial fracture approaches with landmark ratios to predict the location of the infraorbital and supraorbital nerves: an anatomic study

In exposing facial fractures for reduction and fixation with coronal, subciliary, subtarsal, and upper buccal sulcus approaches, the supraorbital and infraorbital nerves are susceptible to injury. The location of the supraorbital and infraorbital nerves can be predicted by palpating for the supraorbital notch. Significant edema as seen with facial fractures can make these prominent bony landmarks difficult to palpate, however. The purpose of this study was to determine a method to predict the location of the supraorbital and infraorbital nerves in the face of frontal and periorbital edema when the supraorbital and infraorbital nerves are not palpable. The supraorbital and infraorbital nerves were identified in 14 cadaver heads. The orbital width from the medial to lateral canthus was measured. The distance of the vertical vector of the supraorbital and infraorbital nerves from the medial canthus was measured along this horizontal vector of the orbit. The distance of the infraorbital nerve from the infraorbital rim was measured. The orbital width measured 42.2 +/- 1.6 mm from the medial to lateral canthus. The vertical vector of the supraorbital nerve measured 15.9 +/- 1.1 mm from the medial canthus along the horizontal vector of the orbit. The vertical vector of the infraorbital verve measured 16.8 +/- 1.4 mm from the medial canthus along the horizontal vector of the orbit. The infraorbital nerve measured 9.8 +/- 1.0 mm inferior to the infraorbital rim. The medial one third of the orbit measured 14.1 mm. Therefore, the supraorbital and infraorbital nerves are located approximately along the medial third of the orbit, with the upper bound of 95% confidence at 3.1 mm. The location of the supraorbital and infraorbital nerves can be predicted by the previous landmark ratio to within 3 mm.