Traumatic ossicular disruption with isolated fracture of the stapes suprastructure: comparison with incudostapedial...

More severe high frequency hearing loss, especially at 8 kHz, occurs with fracture of the stapes suprastructure (SSF) compared with isolated incudostapedial joint dislocation (ISD). Successful hearing gain can be achieved in the speech range with appropriate ossicular reconstruction.

Traumatic SSF is a rare consequence of head trauma. This study aimed to demonstrate the characteristic features of SSF compared with traumatic ISD.

Eighteen patients who suffered from conductive hearing loss after head trauma and were operated from 2000 to 2012 were enrolled. Eight and 10 patients were confirmed to have a traumatic SSF (SSF group) and ISD (ISD group), respectively. The etiology of ossicular disruption, preoperative CT scan of the temporal bone, and intraoperative findings were retrospectively reviewed. Pre- and postoperative hearing was analyzed by both pure tone averages and thresholds at each frequency (0.5-8 kHz).

The most common etiologies in the SSF group were fall (n = 3) and direct ear trauma (n = 3), and for those in the ISD group, the most common etiology was traffic accident (n = 6). CT scan showed no evidence of fracture in the SSF group, whereas findings of ossicular dislocation were found in 70% of patients in the ISD group. Hearing outcomes according to the frequencies demonstrated that pre- and postoperative hearing loss at 8 kHz was more severe in the SSF group than in the ISD group. In a comparison of hearing outcomes at each frequency, the postoperative hearing threshold at 8 kHz was higher than for other frequencies. Postoperatively, 63% of the SSF group and 70% of the ISD group obtained an air-bone gap of within 15 dB.