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Collection of Skeletal Muscle Biopsies from the Superior Compartment of Human Musculus Tibialis Anterior for Mechanical Evaluation
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An Anatomical Variation of the Anconeus Epitrochlearis Muscle: A Case Report
Andrew T Casteel1, Braden R McNees1, Joe Iwanaga1
1Neurosurgery, Tulane University School of Medicine, New Orleans, USA.
Cureus
|August 27, 2025
Summary
This case report details a rare three-headed anconeus epitrochlearis muscle (AEM) variant found in a cadaver. This anatomical anomaly, potentially linked to cubital tunnel syndrome, is the first documented instance of a three-headed AEM.
Area of Science:
- Anatomy
- Human Anatomy
- Musculoskeletal System
Background:
- The anconeus epitrochlearis muscle (AEM) is an anatomical variant.
- It is thought to be evolutionarily linked to climbing behaviors.
- Typically, the AEM presents as a single-headed muscle originating from the humerus and inserting into the olecranon, innervated by the ulnar nerve.
Observation:
- A rare three-headed anconeus epitrochlearis muscle (AEM) was discovered during a routine cadaveric dissection.
- The right AEM displayed a typical single-headed structure.
- The left AEM exhibited three distinct heads, with the proximal head positioned unusually deep to the ulnar nerve.
Findings:
- This is the first reported case of a three-headed anconeus epitrochlearis muscle (AEM).
- Measurements confirmed the unique morphology of the three-headed variant.
- The deep positioning of the proximal head relative to the ulnar nerve is a novel anatomical observation.
Implications:
- Anatomical variants like the AEM can have clinical significance, particularly concerning cubital tunnel syndrome.
- Understanding AEM variations may aid in diagnosing and treating ulnar nerve compression.
- This finding contributes novel anatomical data to the literature, potentially impacting surgical approaches and understanding of nerve pathologies.
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