Hearing loss following temporal bone fractures- a study on classification of fractures and the prognosis

Background: Temporal bone fractures are traditionally classified as transverse, longitudinal or mixed fractures depending on their relationship to the petrous pyramid. However recent studies show that classifying temporal bone fractures as otic capsule sparing (OCS) and otic capsule violating (OCV) types has more relevance with the prognosis of hearing loss and other associated complications. To assess the predictive value of two different types of temporal bone fracture classification systems with respect to hearing loss and its type. Methods: This prospective study was done on patients attending a tertiary care hospital in the study period of one year. Temporal bone fracture patients satisfying inclusion and exclusion criteria were clinically and audiologically evaluated. All patients with temporal bone fractures were categorized into two groups - Longitudinal/ Transverse (old) and OCS / OCV (new). Hearing loss was evaluated audiologically on multiple intervals- initially following the injury once the patient is stable, later after a gap of 1 month and 3 months following the injury. Results: During the study period, 45 patients presenting with temporal bone fractures who satisfied the selection criteria were evaluated. The correlation was statistically significant for new classification system ( P - 0.000) with respect to severity and prognosis of hearing loss which was not the case with the old system ( P - 0.450). Conclusions: We found that classifying temporal bone fractures into OCV and OCS correlates well with the severity of the hearing loss, the prognosis of the patient and the residual hearing disability when compared to the traditional system.