Type of Article:  Original Research

Volume 10; Issue 1 (March 2022)

Page No.: 8262-8268

DOI: https://dx.doi.org/10.16965/ijar.2021.198

A Cadaveric Study on the Anomalous Extensors of the Hand

N. Esakkiammal 1, Archana Rajasundram *2, Rakhee Sharma 3, WMS.Johnson 4.

1  Ph.D Scholar, BIHER Chennai, Tamilnadu, India. https://orcid.org/0000-0002-7024-7223

*2 Associate Professor, Department of Anatomy, Sree Balaji Medical College and Hospital, Chennai, Tamilnadu, India. https://orcid.org/0000-0003-3960-8390

3 Assistant Professor, Department of Anatomy, University College of Medical Sciences, Delhi, India. https://orcid.org/0000-0003-1414-2723

4 Professor and Dean, Sree Balaji Medical College and Hospital, Chennai, Tamilnadu, India.                       https://orcid.org/0000-0002-2522-3783

Corresponding Author: Dr. Archana Rajasundaram, Associate Professor of Anatomy, # 7 Works road, Sree Balaji Medical College and Hospital, Chennai 600044, Tamilnadu, India. E-Mail: archana09@yahoo.com. 9884471721


Background: The hands play a pivotal role in skilled movements. Anomalous muscles of the extensors of the hand are seen usually in anatomical dissections and during surgeries. Variations of the muscles in the dorsum of hand may be asymptomatic or may cause dorsal wrist pain, particularly if a muscle belly encroaches on and obstruct the wrist’s small extensor compartments deep to extensor retinaculum.

Methods: A total of 54 upper limb specimens were used for the current study from the Anatomy Department of an undergraduate & postgraduate teaching Medical College in India. Incidence of additional muscle belly and its tendon in the posterior compartment of the forearm and dorsum of the hand were noted and photographed.

Results: The anomalous muscle bellies and tendons in extensor compartment of forearm and dorsum of hand were observed in 10 limbs (18.5%) of 54 limbs. Of which, the extensor medii proprius (EMP) was 9.3%, extensor digitorum brevis manus (EDBM) was 3.7%. The numbers of the tendon of the extensor digitorum (ED) were varied in 3 limbs (5.6%).

Conclusion: Knowledge of anatomical data of such variant muscles and additional belly or tendon in the extensor compartment of forearm and dorsum of hand is essential for surgeons to modify treatment plan, so as to avoid reporting error and of surgical procedures while operating on hand.

Key words: Hand extensors, Anomalous muscles, Extensor mediiproprius, Extensor digitorum brevis manus, Extensor digitorum.


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Cite this article: N. Esakkiammal, Archana Rajasundram, Rakhee Sharma, WMS. Johnson. A Cadaveric Study on the Anomalous Extensors of the Hand. Int J Anat Res 2022;10(1):8262-8268. DOI: 10.16965/ijar.2021.198