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Published on: January 4, 2017
The lenticular process of the incus
Evan M Graboyes1, Timothy E Hullar, Richard A Chole
1Department of Otolaryngology, Washington University in St. Louis, St. Louis, Missouri, USA.
Summary
The lenticular process of the incus was historically misidentified as a separate ossicle. Anatomical studies confirmed it is an integral part of the incus, attached by a thin strut.
Area of Science:
- Anatomy
- History of Medicine
- Otolaryngology
Background:
- Seventeenth-century anatomists, including Franciscus Sylvius, described a small bony structure between the incus and stapes.
- This structure was believed to be a separate, fourth ossicle, leading to centuries of debate.
Observation:
- The existence and nature of this ossicle were controversial for approximately 200 years.
- Prominent 19th-century anatomists like Blumenbach and Soemmerring argued against its status as a separate bone.
Findings:
- Detailed historical review confirmed the structure was initially considered an independent ossicle.
- Later anatomical evidence demonstrated it is attached to the incus by a thin strut, not a separate bone.
Implications:
- The ovoid end of the incus should be termed the "lenticular process."
- Accurate nomenclature for the bony connection remains a subject of discussion.
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