Anatomic Study of the Innervation of Extensor Carpi Radialis Longus and Extensor Carpi Radialis Brevis. Interest in Nerve Transfers

Abstract

Objective

This study pretends to describe the innervation pattern of Extensor Carpi Radialis Longus (ECRL) and Extensor Carpi Radialis Brevis (ECRB) to use ECRL branches as a first choice in nerve transfers to restore flexion and extension of wrist and fingers due to its easier identification and its redundant innervation.

Methods

Nine cryopreserved and anonymous specimens were dissected to identify the radial nerve and describe its number of branches, the distance between its origin and a line connecting both epicondyles, the length of each branch, and the type of innervation of ECRL and ECRB according to Taylor's classification.

Results

Six out of nine specimens presented two branches from the radial nerve to innervate the ECRL (Taylor type 3). Three out of nine specimens only had one branch to innervate the ECRL, originating from the radial nerve (two of them classified as a Taylor type 1 and the other as a Taylor type 2). All the specimens had only one branch to innervate the ECRB (eight showing a Taylor type 1 pattern, and one classified as Taylor type 2); in seven out of nine, this branch emerges from the deep branch of the radial nerve, emerging in the other two specimens from the superficial branch of the radial nerve.

Conclusion

The use of the ECRL branches could be considered the first choice in nerve transfers to restore the flexion and extension of the elbow, wrist and fingers in nerve injuries, because of its constant origin after the brachioradialis branch and in most of the cases its redundant innervation.

Level of evidence: VI

Keywords

anatomy - nerve injury - brachial plexus - nerve transfers

Ethics Approval

The study was performed in accordance with the ethical standards laid down in the 1964 Declaration of Helsinki.

Author's Contributions

All authors contributed equally to this work. All authors contributed to the study conception and design, material preparation, data collection, and analysis. The first draft of the manuscript was written by Pablo Martínez Collado and Rosa Morro Martí.

Publication History

Received: 02 July 2024

Accepted: 24 March 2025

Article published online:
21 July 2025

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