Surgically-Relevant Anatomy of the External Auditory Canal Bulge and Scutum

Conclusion: Prominent anterior canal bulges are formed by posterior temporomandibular joints, not thicker bone. The scutum has asymmetric distances to various portions of the ossicles with the incus short process sometimes as close as 0.2 mm, placing it at risk of injury.
Source: Otology and Neurotology - Category: ENT & OMF Tags: BASIC SCIENCE Source Type: research