Kristie Williamson, Weber State University
Athletic Training
Context: Cranial Nerve V (CN V; Trigeminal nerve) is responsible for facial sensation. CN V has three separate branches which include ophthalmic, maxillary and mandibular. The ophthalmic nerve (V1) carries sensory information from the forehead; the maxillary nerve (V2) carries information from the cheek; and the mandibular nerve (V3) carries information from the chin. It is important to test all three areas of cranial nerve V to accurately assess full nerve function. Previous research has indicated that pressure threshold is not affected by age, however, normative values for two-point discrimination for CN V have not yet been established and may prove useful in concussion evaluation. Objective: Initial investigation aimed at determining gender-specific normative values for CN V two-point discrimination. Design: Prospective repeated-measures design. Setting: This study was performed in the athletic training facilities on the campus of a large Division I institution. Patients or Other Participants: Convenience sample of 106 healthy students enrolled at our institution (43 females, average age: 23.2; 63 males, average age: 22.1). Participants had no history of concussion within the last year, no facial scaring or plastic surgery and not a current smoker. Interventions: Measurement was taken using a two-point discriminator (Disk-Criminator) on the mid-forehead, mid-cheek, and mid-chin. Participants closed their eyes while each measurement was taken. Light pressure was applied (force equal to approximately 10-15 grams to produce blanching of the skin). Measurements were taken three times on each of three facial locations, sequentially. The smallest number in millimeters (mm) to correctly discriminate one/two points was recorded. The two pressure points were applied at exactly the same time. Main Outcome Measure: Discrimination score for each test location (mid-forehead, mid-cheek, mid-chin). Nested average was calculated within subjects for each test location; average was calculated between subjects for each test location. One-way between-subjects ANOVAs were conducted to evaluate potential differences in gender for each test location. Results: Between-subjects average for mid-forehead was 7.8mm (+/2.9), for mid-cheek was 10.4mm (+/2.6), and for mid-chin was 5.9mm (+/1.9). There was a significant effect for gender for cheek normative value (p<0.01); average discrimination score for males was 11mm, average for female was 9.7mm.