Posterior branch of the axillary nerve transfer to the lateral triceps branch for restoration of elbow extension: case report

Pre-operative electrodiagnostic planning for upper limb peripheral nerve transfers in cervical spinal cord injury: A Narrative Review

Peripheral nerve transfer (PNT) to improve upper limb function following cervical spinal cord injury (SCI) involves the transfer of supralesional donor nerves under voluntary control to intralesional or sublesional lower motor neurons not under voluntary control. Appropriate selection of donor and recipient nerves and surgical timing impact functional outcomes. While the gold standard of nerve selection is intra-operative nerve stimulation, preoperative electrodiagnostic (EDX) evaluation may help guide surgical planning. Currently there is no standardized preoperative EDX protocol. This study reviews the EDX workup preceding peripheral nerve transfer surgery in cervical SCI, and proposes an informed EDX protocol to assist with surgical planning. The PICO (Population, Intervention, Comparison, Outcome) framework was used to formulate relevant MeSH terms and identify published cases of PNT in cervical SCI in Medline, Embase, CINAHL, and Emcare databases in the last 10 years. The electrodiagnostic techniques evaluating putative donor nerves, recipient nerve branches, time-sensitivity of nerve transfer and other electrophysiological parameters were summarized to guide creation of a preoperative EDX protocol. Needle electromyography (EMG) was the most commonly used EDX technique to identify healthy donor nerves. Although needle EMG has also been used on recipient nerves, compound muscle action potential (CMAP) amplitudes may provide a more accurate determination of recipient nerve health and time-sensitivity for nerve transfer. While there has been progress in pre-surgical EDX evaluation, EMG and NCS approaches are quite variable, and each has limitations in their utility for pre-operative planning. There is need for standardization in the EDX evaluation preceding peripheral nerve transfer surgery to assist with donor and recipient nerve selection, surgical timing and to optimize outcomes. Based on results of this review, herein we propose the PreSCIse (PRotocol for Electrodiagnosis in SCI Surgery of the upper Extremity) pre-operative EDX panel to achieve said goals through an interdisciplinary and patient-centered approach. This article is protected by copyright. All rights reserved.

The Intercostal Nerves Transfer to the Radial Nerve Branch to the Long Head Triceps Muscle: Influencing Factor and Outcome of 55 Cases

PURPOSE

The objective of this study was to report the functional outcomes and factors affecting the result of intercostal nerves transfer to the radial nerve branch to the long head triceps muscle for restoration of elbow extension in patients with total brachial plexus palsy or C5 to C7 palsy with the loss of triceps muscle function.

METHODS

Fifty-five patients with total brachial plexus palsy or C5 to C7 palsy with no triceps muscle function had a reconstruction of elbow extension by transferring the third to fifth intercostal nerves to the radial nerve branch to the long head triceps muscle. The functional outcomes determined by the Medical Research Council grading were evaluated. Factors influencing the outcomes were determined using logistic regression analysis.

RESULTS

At the follow-up of at least 2 years, 36 patients (65%) had antigravity motor function (Medical Research Council grade, ≥3). Multivariable logistic regression analysis showed that the body mass index, time to surgery, and injury of the dominant limb were associated with the outcome.

CONCLUSIONS

The third to fifth intercostal nerves transfer to the radial nerve branch to the long head triceps muscle is an effective procedure to restore elbow extension. We would recommend using 3 intercostal nerves without grafts; in cases of nerve root avulsion in which there is no chance of spontaneous recovery, early surgery should be considered.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Upper-Extremity Reconstruction in Tetraplegia: A Critical Analysis Review

Management of tetraplegia should be individualized to a patient's particular deficiencies and functional goals. Surgical decision-making for upper-extremity reconstruction in patients with tetraplegia relies on a thorough physical examination to determine which nerves and muscles remain under volitional control with adequate strength for transfer. Peripheral nerve transfers, either in conjunction with or in place of traditional tendon transfers, enable providers to offer an expanded set of surgical options for patients with tetraplegia who are seeking upper-extremity reconstruction. All upper-extremity reconstructive efforts should be carefully considered with regard to their potential effects on the availability of future reconstructive efforts.

Comparative Study of Intercostal Nerve and Contralateral C7 Nerve Transfers for Elbow Extension After Global Brachial Plexus Avulsion

INTRODUCTION

Elbow extensive reconstruction was essential for the patients with brachial plexus avulsion. Nerve transfer was applied to repair elbow extension, but the ultimate recovery was quite different. The purpose of this study was to compare the effects of elbow extension in patients with global brachial plexus avulsion after repaired by intercostal nerve (ICN) and contralateral cervical 7 (cC7) nerve transfer to the long head branch of triceps and to analyze the possible influencing factors.

MATERIALS AND METHODS

A retrospective review of 24 patients treated with ICN and cC7 nerve transfer for elbow extension in posttraumatic global brachial plexus avulsion was carried out. Two ICNs were used as donors in 17 patients, and cC7 nerve was used in the other 7 patients. We evaluated the recovery of elbow extension by the British Medical Research Council grading system and electromyography. The correlation between age, preoperative interval, and prognosis was analyzed in this study.

RESULTS

Efficiency of elbow extensor strength in the ICN transfer group was 47.06%, and it was 28.57% in the cC7 nerve transfer group, but there was no significant difference (P = 0.653). The effective recovery of electromyography in ICN transfer group was 82.35%, whereas in the group cC7 nerve transfer, it was 28.57%, there was a statistical difference between the 2 groups (P = 0.021). Age and interval were negatively correlated with prognosis.

CONCLUSIONS

Intercostal nerve or cC7 nerve transfer to the long head branch of triceps could reconstruct elbow extension to some extent. Compared with cC7 nerve transfer, ICN transfer had a greater result for elbow extension, but the difference in extension power was not significant, whereas there was difference in electromyography recovery. Patient's age and interval were negatively correlated with the results.

Distal Nerve Transfers to the Triceps Brachii Muscle: Surgical Technique and Clinical Outcomes

PURPOSE

To report the clinical outcomes and describe the surgical technique of triceps muscle reinnervation using 2 different distal nerve transfers: the flexor carpi ulnaris (FCU) fascicle of the ulnar nerve and the posterior branch of the axillary nerve (PBAN) to the triceps nerve branch.

METHODS

A retrospective review of patients undergoing FCU fascicle of ulnar nerve or PBAN to triceps nerve branch transfer was performed. Outcome measures included preoperative and postoperative modified British Medical Research Council (MRC) score, EMG results, and complications.

RESULTS

Between September 2003 and April 2017, 6 patients were identified. Four patients with a traumatic upper trunk and posterior cord palsy underwent ulnar nerve fascicle to triceps nerve transfer. Two patients with a recovering upper trunk following a pan-brachial plexus palsy underwent PBAN to triceps nerve branch transfer. The median age was 30.0 years (range, 18-68 years). Surgery was performed at a median of 6.9 months (range, 5.0-8.9 months) postinjury, with a median follow-up of 18.4 months (range, 7.6-176.3) months. Before surgery, 4 patients exhibited grade M0 and 2 patients exhibited grade M1 triceps strength. Four patients had M5 donor muscle strength and 2 had grade M4. Postoperatively, 4 patients regained MRC grade M4 triceps muscle strength, 1 regained M3, and 1 regained M2. There was no noticeable donor muscle weakness.

CONCLUSIONS

Nerve fascicles to the FCU and PBAN are viable options for obtaining meaningful triceps muscle recovery in a select group of patients.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Combined flexor carpi ulnaris and flexor carpi radialis transfer for restoring elbow function after brachial plexus injury

The result of combined agonist and antagonist muscle innervation in traumatic brachial plexus injury through the intraplexal fascicle nerve transfers with the same donor function has not yet been reported. We describe a patient with a C5-C7 traumatic brachial plexus injury who had a combined transfer of the flexor carpi radialis (FCR) fascicle to the musculocutaneous nerve and the flexor carpi ulnaris (FCU) fascicle to the radial nerve of the triceps. The patient returned for his follow-up visit 2 years after his surgery. The muscle strengths of his triceps and biceps were Medical Research Council grade 2 and 0, respectively. Compared with his uninjured side, his grip strength was 9.8%, and his pinch strength was 14.2%. Our case report provides insights on result of combined agonist and antagonist muscle innervation through combining the motor fascicle of the FCR and FCU to restore the elbow flexor and extensor. The result may not be promising.

Upper Extremity Innervation Patterns and Clinical Implications for Nerve and Tendon Transfer

BACKGROUND

The authors previously studied the intramuscular innervation of 150 upper limb muscles and demonstrated that certain patterns of intramuscular innervation allowed muscles to be split into compartments with independent function. This study aims to determine the location, extramuscular course, and number of motor nerve branches of upper limb peripheral nerves. The authors want to combine this information with their previous work to create a blueprint of upper limb neuromuscular anatomy that would be useful in reconstructive surgery.

METHODS

Ten fresh frozen cadaveric upper limbs were dissected. The origin of branches from the peripheral nerve trunk, their course, and the number of motor nerves per muscle were determined. The authors reviewed all the images of the Sihler-stained muscles from their earlier study.

RESULTS

Motor nerve branches arise at the intersection of nerve trunk and muscle belly and are clustered near the origin of muscle groups. Two patterns of extramuscular innervation were noted, with one group having a single motor nerve and another group with consistently more than one motor nerve. A modified classification of muscles was proposed based on the orientation of muscle fibers to the long axis of the limb, the number of muscle compartments, and the number of heads of origin or the tendons of insertion.

CONCLUSIONS

Motor nerve clusters can be located based on fixed anatomical landmarks. Muscles with multiple motor nerves have morphology that allows them to be split into individual compartments. The authors created a muscle and nerve blueprint that helps in planning nerve and split muscle transfers.

Nerve Transfers to Restore Elbow Function

The purpose of this article is to provide an overview of the various nerve transfer options for restoration of elbow function. This article describes nerve transfer strategies for elbow flexion and extension including the indications, limitations, and expected outcomes based on current literature.

Transfer of a Terminal Motor Branch Nerve to the Flexor Carpi Ulnaris for Triceps Reinnervation: Anatomical Study and Clinical Cases

PURPOSE

To analyze the anatomical feasibility of transferring a motor branch nerve to the flexor carpi ulnaris (FCU) to the triceps upper medial head motor branch (UMHM) and to report the resultant outcome of the restoration of elbow extension in 5 patients with extensive brachial plexus injury.

METHODS

The ulnar and radial nerves were dissected in 10 cadavers. We measured the length and diameter of the branches to the FCU and the UMHM branch and counted the axons. Then, 5 male patients, mean age 30 years, underwent FCU nerve branch transfer for reconstruction of elbow extension. Elbow flexion was restored via a median nerve branch to biceps transfer.

RESULTS

Mean UMHM nerve length and diameter were 86 and 1.5 mm, respectively. Mean number of branches to the FCU muscle was 2.9. Mean FCU nerve length and diameter were 50 and 1.0 mm, respectively. Mean number of myelinated fibers was 818 and 743 for the UMHM and the longest branch to the FCU, respectively. Coaptation between nerves was possible without tension. All patients recovered functional active elbow extension at a mean follow-up of 19 months with a British Medical Research Council score of M4. After surgery, all patients retained a functional FCU with a British Medical Research Council score of M4.

CONCLUSIONS

Nonselective ulnar nerve fascicles at the root of the limb might not be adequate to restore elbow extension when combined with a median nerve branch transfer for elbow flexion. A selective distal ulnar motor fascicle such as a FCU motor branch could be harvested and connected to a triceps branch to restore elbow extension. Such a nerve transfer would also allow for later transfer of the still functional FCU tendon to the digital extensors.

CLINICAL RELEVANCE

For patients with extensive brachial plexus injury and a preserved medial cord, transferring a motor branch nerve to the FCU is an effective technique for the reconstruction of elbow extension.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Motor Nerve Transfers

Brachial plexus and peripheral nerve injuries are exceedingly common. Traditional nerve grafting reconstruction strategies and techniques have not changed significantly over the last 3 decades. Increased experience and wider adoption of nerve transfers as part of the reconstructive strategy have resulted in a marked improvement in clinical outcomes. We review the options, outcomes, and indications for nerve transfers to treat brachial plexus and upper- and lower-extremity peripheral nerve injuries, and we explore the increasing use of nerve transfers for facial nerve and spinal cord injuries. Each section provides an overview of donor and recipient options for nerve transfer and of the relevant anatomy specific to the desired function.

Thoracodorsal nerve transfer for triceps reinnervation in partial brachial plexus injuries

PURPOSE

To report the clinical outcomes of thoracodorsal nerve (TDN) transfers to the triceps motor branches for elbow extension restoration in patients with partial brachial plexus injuries (BPI).

METHODS

Eight male patients of mean age 23 years and suffering from a partial BPI underwent direct coaptation of the TDN to the nerve of the upper medial and long heads of the triceps, an average 6 months after their accident.

RESULTS

Seven patients achieved M4 elbow extension strength and one patient M3, according to the BMRC scale, after a mean follow-up of 21 months.

DISCUSSION

Direct TDN transfer might be a valid surgical procedure for the restoration of elbow extension in patients with partial BPI.

Peripheral nerve injuries: advancing the field through research, collaboration, and education

The Andrew J. Weiland Medal is presented each year by the American Society for Surgery of the Hand and the American Foundation for Surgery of the Hand for a body of work related to hand surgery research. This essay, awarded the Weiland Medal in 2013, focuses on advancing the field of peripheral nerve injuries through research, collaboration, and education.