Isolated Fracture of the Malleus: An Overlooked Cause of Conductive Hearing Loss?

Abstract

To report the largest case series of isolated malleus fractures with systematic review to characterize the disease's presentation and natural history, and provide suggestions for management. PubMed, Embase, Cochrane Library. Retrospective cohort study was performed on 12 patients with isolated malleus fractures. History, physical exam, pre- and post-treatment audiograms, and imaging were obtained. Systematic review of the literature was performed. Including the cases herein, 58 isolated malleus fractures were identified, the majority of which were published in the 21st century. Mean time to presentation after injury was 34.4 months. Most common etiology was external auditory canal (EAC) manipulation. Physical exam and imaging did not identify any abnormality at presentation in 16% and 21% of cases, respectively. The majority of fractures involved the manubrium. Air-bone gap (ABG) at initial presentation ranged from 16 to 26 dB, and was greater at higher frequencies. Thirty-six cases underwent surgery. ABG improvement was greater at all frequencies for those who underwent surgery. Final ABG was significantly less than initial ABG at nearly every frequency for those who underwent surgery (p < 0.05), while not at any frequency for those who were observed. Isolated malleus fractures may occur more often than historical data suggests, and are perhaps underdiagnosed. Abrupt removal of a finger from the EAC with pain and hearing loss is nearly pathognomonic. Conductive hearing loss with ABG greater at higher frequencies is most often observed. Observation is unlikely to produce spontaneous improvements in hearing, while surgery demonstrates reliable decreases in ABG. Laryngoscope, 134:1032-1041, 2024.