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An anatomical study of additional radial wrist extensors including a unique extensor carpi radialis accessorius
Affiliations- University of Cambridge
- Brighton and Sussex University Hospitals NHS Trust
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Abstract
Background: In this study, 82 forearms from 41 cadavers were dissected to establish the incidence of variant additional radial wrist extensors. Three variants have been described in the literature: extensor carpi radialis intermedius (ECRI), extensor carpi radialis accessorius (ECRA) and extensor carpi radialis tertius (ECRT).
Materials and methods: Of the 41 cadavers studied, 5/41 (12%) had an additional radial wrist extensor. Of these 5 individuals, 2 had bilateral additional muscles and 3 were unilateral. Of the 82 forearms, 7/82 (9%) had additional radial wrist extensors.
Results: We found 4 examples of ECRI and 3 examples of ECRA. We did not find any examples of ECRT. One specimen of ECRA had an atypical, previously undescribed, course.
Conclusions: These accessory muscles are of clinical relevance, as they may be a contributing factor in tennis elbow and nerve entrapment, or cause diagnostic confusion, especially in ultrasound scans. However, they may also be used for tendon transfer. Of the 7 muscles found in the current study, 3 would have been suitable for such procedures.
Abstract
Background: In this study, 82 forearms from 41 cadavers were dissected to establish the incidence of variant additional radial wrist extensors. Three variants have been described in the literature: extensor carpi radialis intermedius (ECRI), extensor carpi radialis accessorius (ECRA) and extensor carpi radialis tertius (ECRT).
Materials and methods: Of the 41 cadavers studied, 5/41 (12%) had an additional radial wrist extensor. Of these 5 individuals, 2 had bilateral additional muscles and 3 were unilateral. Of the 82 forearms, 7/82 (9%) had additional radial wrist extensors.
Results: We found 4 examples of ECRI and 3 examples of ECRA. We did not find any examples of ECRT. One specimen of ECRA had an atypical, previously undescribed, course.
Conclusions: These accessory muscles are of clinical relevance, as they may be a contributing factor in tennis elbow and nerve entrapment, or cause diagnostic confusion, especially in ultrasound scans. However, they may also be used for tendon transfer. Of the 7 muscles found in the current study, 3 would have been suitable for such procedures.
Keywords
extensor carpi radialis brevis, extensor carpi radialis longus, extensor carpi radialis accessorius, extensor carpi radialis intermedius
About this articleTitle
An anatomical study of additional radial wrist extensors including a unique extensor carpi radialis accessorius
Journal
Issue
Article type
Original article
Pages
742-747
Published online
2017-05-25
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2684
Article views/downloads
2274
DOI
Pubmed
Bibliographic record
Folia Morphol 2017;76(4):742-747.
Keywords
extensor carpi radialis brevis
extensor carpi radialis longus
extensor carpi radialis accessorius
extensor carpi radialis intermedius
Authors
C. T. West
D. Ricketts
C. Brassett
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