Histopathology of the Incudomalleolar Joint in Cases of

Abstract

Age-related hearing loss (presbycusis) is a prevalent condition attributed primarily to inner ear dysfunction. Little is known about age-related changes in the ossicular joints or their contribution to presbycusis. Herein, we performed a histopathologic analysis of the incudomalleolar joint (IMJ) in specimens from the National Temporal Bone Registry with audiometrically confirmed presbycusis but without histologically observed sensory, neural, strial, or mixed features. Seventeen “indeterminate” presbycusis (IP) ears and 13 young, normal-hearing ears were examined. The age was 73.2 ± 9.5 years for the IP group and 32.1 ± 9.5 for the young group (P < .05). The joint space between the 2 ossicles was 23% wider in the IP group (139 ± 26.2 µm) compared to young ears (113 ± 49.0 µm) (P = .02). We report that IP ears have a wider IMJ than young ears. These findings have implications for understanding the etiology of presbycusis in indeterminate cases.