Electrophysiological study of the dominant motor innervation to the extensor digitorum communis muscle and long head of triceps brachii at posterior divisions of brachial plexus

The ulnar nerve is considered the thickest terminal branch of the medial cord in the brachial plexus and most authors does not mention the possibility of this nerve emitting branches to the arm. However, some studies reported that the ulnar nerve could supply the medial head of triceps brachii muscle. The main objective in this study was identifying the presence of ulnar nerve branches in triceps brachii muscle. Sixty upper limbs of adult Brazilian corpses of both sexes were used. The estimated age was between 25 and 80 years old. Every studied piece had the nerves and their branches quantified and measured with a manual mechanic caliper. The branches were photographed and had the data registered in individual files. Were found ulnar nerve branches for all the heads of triceps brachii muscle: 1 branch (9,1%) to lateral head, 2 branches (18,1%) to long head and 8 branches (72,7%) to medial head. Thus, we can conclude that the contribution of ulnar nerve to triceps brachii muscle constitutes an important anatomical variation.Key words: Ulnar nerve; Triceps brachii muscle; Innervation.

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Spinal Nerve Origins of the Muscular Branches of the Radial Nerve

Neurosurgery ◽

10.1227/neu.0b013e3182486b35 ◽

2012 ◽

Vol 70 (6) ◽

pp. 1438-1441 ◽

Cited By ~ 5

Author(s):

Lei Zhang ◽

Cheng-Gang Zhang ◽

Zhen Dong ◽

Yu-Dong Gu

Keyword(s):

Brachial Plexus ◽

Radial Nerve ◽

Compound Muscle Action Potential ◽

Electrophysiological Study ◽

Spinal Nerve ◽

Posterior Interosseous Nerve ◽

Triceps Brachii ◽

Nerve Roots ◽

Extensor Pollicis Longus ◽

Significant Difference

Abstract BACKGROUND: In injuries of the lower brachial plexus, finger flexion can be restored by nerve or tendon transfer. However, there is no technique that can guarantee good recovery of finger and thumb extension. OBJECTIVE: To determine the spinal nerve origins of the muscular branches of the radial nerve and identify potential intraplexus donor nerves for neurotization of the posterior interosseous nerve in patients with lower brachial plexus injuries. METHODS: An intraoperative electrophysiological study was carried out during 16 contralateral C7 nerve transfers. The compound muscle action potential of each muscle innervated by the radial nerve was recorded while the C5-T1 nerves were individually stimulated. RESULTS: The triceps brachii muscle primarily received root contributions from C7. The C5 and C6 nerve roots displayed greater amplitudes for the brachioradialis and supinator muscles compared with those of the C7, C8, and T1 nerve roots (P < .05). The extensor carpi radialis branch was innervated by C5, C6, and C7, and no significant differences were detected between them (P > .05). The amplitudes obtained for the extensor digitorum communis branch were the largest from C7 and C8, without a significant difference between them (P > .05), whereas the amplitudes of the extensor carpi ulnaris and extensor pollicis longus were largest from the C8 root (P < .05). CONCLUSION: The supinator muscle branch is likely the best donor nerve for the repair of lower brachial plexus injuries affecting muscles that are innervated by the posterior interosseous nerve.

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Motor innervation, motor unit organization and afferent innervation of m. extensor digitorum communis of the baboon's forearm

The Journal of Physiology ◽

10.1113/jphysiol.1968.sp008600 ◽

1968 ◽

Vol 198 (1) ◽

pp. 179-192 ◽

Cited By ~ 21

Author(s):

Rosamond M. Eccles ◽

C. G. Phillips ◽

Wu Chien-Ping

Keyword(s):

Motor Unit ◽

Extensor Digitorum ◽

Extensor Digitorum Communis ◽

Motor Innervation ◽

Unit Organization ◽

Afferent Innervation

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Reanimation of elbow extension with medial pectoral nerve transfer in partial injuries to the brachial plexus

Journal of Neurosurgery ◽

10.3171/2012.11.jns111539 ◽

2013 ◽

Vol 118 (3) ◽

pp. 588-593 ◽

Cited By ~ 13

Author(s):

Leandro Pretto Flores

Keyword(s):

Brachial Plexus ◽

Radial Nerve ◽

Research Council ◽

Medical Research Council ◽

Nerve Transfer ◽

Elbow Extension ◽

Triceps Brachii ◽

Pectoral Nerve ◽

Medial Pectoral Nerve ◽

Long Head

Object Recent advancements in operative treatment of the brachial plexus authorized more extensive repairs and, currently, elbow extension can be included in the rank of desirable functions to be restored. This study aims to describe the author's experience in using the medial pectoral nerve for reinnervation of the triceps brachii in patients sustaining C5–7 palsies of the brachial plexus. Methods This is a retrospective study of the outcomes regarding recovery of elbow extension in 12 patients who underwent transfer of the medial pectoral nerve to the radial nerve or to the branch of the long head of the triceps. Results The radial nerve was targeted in 3 patients, and the branch to the long head of the triceps was targeted in 9. Grafts were used in 6 patients. Outcomes assessed as Medical Research Council Grades M4 and M3 for elbow extension were noted in 7 (58%) and 5 (42%) patients, respectively. Conclusions The medial pectoral nerve is a reliable donor for elbow extension recovery in patients who have sustained C5–7 nerve root injuries.

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Anatomic cadaveric study of the extensile extensor digitorum communis splitting approach for exposing the ulnar coronoid process

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2016.01.008 ◽

2016 ◽

Vol 25 (8) ◽

pp. 1268-1273 ◽

Cited By ~ 7

Author(s):

Koji Sukegawa ◽

Takane Suzuki ◽

Yasufumi Ogawa ◽

Keisuke Ueno ◽

Hitoshi Kiuchi ◽

...

Keyword(s):

Cadaveric Study ◽

Extensor Digitorum ◽

Coronoid Process ◽

Extensor Digitorum Communis

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Transfer of a Motor Fascicle From the Ulnar Nerve to the Branch of the Radial Nerve Destined to the Long Head of the Triceps for Restoration of Elbow Extension in Brachial Plexus Surgery

Neurosurgery ◽

10.1227/neu.0b013e31822ac120 ◽

2011 ◽

Vol 70 (2) ◽

pp. E516-E520 ◽

Cited By ~ 11

Author(s):

Leandro Pretto Flores

Keyword(s):

Computed Tomography ◽

Brachial Plexus ◽

Ulnar Nerve ◽

Radial Nerve ◽

Nerve Transfer ◽

Elbow Flexion ◽

Shoulder Abduction ◽

Elbow Extension ◽

Long Head ◽

Brachial Plexus Surgery

Abstract BACKGROUND AND IMPORTANCE: Restoration of elbow extension has not been considered of much importance regarding functional outcomes in brachial plexus surgery; however, the flexion of the elbow joint is only fully effective if the motion can be stabilized, what can be achieved solely if the triceps brachii is coactivated. To present a novel nerve transfer of a healthy motor fascicle from the ulnar nerve to the nerve of the long head of the triceps to restore the elbow extension function in brachial plexus injuries involving the upper and middle trunks. CLINICAL PRESENTATION: Case 1 is a 32-year-old man sustaining a right brachial extended upper plexus injury in a motorcycle accident 5 months before admission. The computed tomography myelogram demonstrated avulsion of the C5 and C6 roots. Case 2 is a 24-year-old man who sustained a C5-C7 injury to the left brachial plexus in a traffic accident 4 months before admission. Computed tomography myelogram demonstrated signs of C6 and C7 root avulsion. The technique included an incision at the medial border of the biceps, in the proximal third of the involved arm, followed by identification of the ulnar nerve, the radial nerve, and the branch to the long head of the triceps. The proximal stump of a motor fascicle from the ulnar nerve was sutured directly to the distal stump of the nerve of the long head of the triceps. Techniques to restore elbow flexion and shoulder abduction were applied in both cases. Triceps strength Medical Research Council M4 grade was obtained in both cases. CONCLUSION: The attempted nerve transfer was effective for restoration of elbow extension in primary brachial plexus surgery; however, it should be selected only for cases in which other reliable donor nerves were used to restore elbow flexion.

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