Comparison of the clinical relevance of traditional and new classification systems of temporal bone fractures

Temporal bone fractures are traditionally classified as transverse, longitudinal or mixed. Since these categories have shown little association with clinical symptoms, new classifications have been introduced, including those related to the involvement of the petrous bone and otic capsule. We have formulated a new classification based on the involvement of four parts of the temporal bone (squama, tympanic, mastoid, and petrous) and assessed which of these classification systems is the most rational using a retrospective chart review in hospital settings (KyungHee Medical Center, Seoul, Korea and Samsung Changwon Hospital, Changwon, Korea). The association between each classification and clinical symptoms was examined by analyzing temporal bone computed tomography scans of 129 patients diagnosed as temporal bone fractures over the past 7 years. Using the traditional classification, there was a significant correlation between transverse fractures and the incidence of sensorineural hearing loss. Patients with petrous bone fractures had significantly higher incidence rates of sensorineural hearing loss, vertigo, and eardrum perforation than patients without petrous bone involvement. Involvement of the otic capsule was significantly associated with sensorineural hearing loss and the severity of hearing loss. The associations of the traditional classification and the classification according to the involvement of the otic capsule, four parts of temporal bone with clinical symptoms were not high. Petrous bone fractures were significantly associated with sensorineural hearing loss, vertigo, and eardrum perforation, suggesting that this classification may be optimally associated with clinical symptoms including hearing and the results of otological examination.