Strategies for the Surgical Treatment of Brachial Plexus Traumatic Injuries: A Survey among Neurosurgeons in Latin America

Abstract

Objective

Peripheral nerve surgeons still disagree on the best moment to operate and on the best surgical strategy to employ in each clinical injury type of brachial plexus lesion. This study surveyed a specific group of neurosurgeons in Latin America to determine their reconstruction strategies for different brachial plexus injury cases.

Methods

A survey was emailed to 46 neurosurgeons who operate at least 15 BPIs per year. The questionnaire was divided into ten questions based on general issues and four hypothetical clinical cases.

Results

There were 23 respondents from five countries, each one performing an average of 35.5 brachial plexus reconstructions annually. Surgery was indicated as soon as possible for Case 1 (adult with complete brachial plexus palsy), predominantly reconstruction with nerve transfers. The same was recommended for Case 2 (adult with C5-C6 lesion). In Case 3 (adult with C8-T1 lesion), most surgeons indicated that surgery should be performed as soon as possible, and nerve transfers should be used for plexus reconstruction. In Case 4 (infant with Erb́s palsy), 40% of the surgeons would operate within three months and 53.3% within six months after birth. Usually complemented by nerve transfers, grafts were chosen by 53.3% of the surgeons. Postoperative rehabilitation was inadequate in more than half of the patients (56.5%).

Conclusions

The survey respondents had many agreements. Nevertheless, there is yet to be a complete consensus on the many persisting issues, and prospective randomized studies are needed to evaluate the merits of each surgical treatment strategy for BPI.

 

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Resumo

Objetivo

Cirurgiões de nervos periféricos ainda discordam com relação ao melhor momento para operar e qual a melhor estratégia cirúrgica a ser empregada em cada tipo de lesão clínica nas lesões do plexo braquial. Este estudo pesquisou um grupo específico de neurocirurgiões na America Latina para determinar suas estratégias de reconstrução para diferentes casos de lesão do plexo braquial.

Métodos

Uma pesquisa foi enviada por correio eletrônico a 46 neurocirurgiões que operam pelo menos 15 casos de lesões do plexo braquial por ano. O questionário foi dividido em dez questões baseadas em problemas gerais e em quatro casos clínicos hipotéticos.

Resultados

Recebemos 23 respostas de cinco países, com uma média de 35,5 reconstruções do plexo braquial por ano, para cada participante. No Caso 1 (adulto com paralisia completa do plexo braquial), a cirurgia foi indicada o mais precoce possível, predominantemente sob a forma de reconstrução com transferências de nervos. Isso foi recomendado para o Caso 2 (adulto com lesão de C5-C6). No Caso 3 (adulto com lesão C8-T1), a maioria dos cirurgiões indicou cirurgia precoce e transferências de nervos para reconstrução do plexo. No Caso 4 (bebê com paralisia de Erb), 40% dos cirurgiões operariam em três meses e 53,3% dentro de seis meses após o nascimento. Nesses casos, a reconstrução com enxertos foi escolhida por 53,3% dos cirurgiões, geralmente complementada com transferências de nervos. A reabilitação pós-operatória foi inadequada em mais da metade dos pacientes (56,5%).

Conclusões

Os participantes da pesquisa concordaram em diversos aspectos do tratamento. No entanto, ainda não existe consenso em muitos pontos e continuamos necessitando de estudos prospectivos randomizados para avaliar os méritos de cada estratégia cirúrgica no tratamento das lesões do plexo braquial.

 

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Keywords

brachial plexus surgery - Latin American neurosurgeons - survey - nerve transfers - adult brachial plexus injury - neonatal brachial plexus injury

Palavras-chave

cirurgia do plexo braquial - neurocirurgiões da America Latina - pesquisa - transferências de nervos - lesão do plexo braquial em adultos - lesão neonatal do plexo braquial

Introduction

Managing brachial plexus injury (BPI) remains challenging for peripheral nerve surgeons. As it is a rare condition, no randomized protocols or standardized measures exist. Surgeons often disagree about the best approach for repairing BPIs.

To understand how Latin American neurosurgeons engage in peripheral nerve surgery for BPI treatment, a survey was undertaken. The aim was to (1) determine each surgeon's level and opportunity of training, and pre-surgical studies that allowed them to determine their approach to each case, and (2) understand how and when this community of surgeons deals with these patients.

 

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Methods

After obtaining approval from the Institutional Review Board of the University of São Paulo Medical School and of the University of Buenos Aires School of Medicine, an online questionnaire was sent to all Latin American neurosurgeons who were experienced enough in peripheral nerve surgery. Each Latin American country was carefully analyzed to determine possible candidates for the survey, and they were contacted via mail or phone. The nerve surgeon had to be a neurosurgeon who participates and executes ≥ 15 brachial plexus surgeries annually.

Based on two publications from the Johns Hopkins University School of Medicine[1] [2] we developed a 10-question survey and four hypothetical clinical cases (three adults and one pediatric) and emailed them to 46 potential participants to evaluate the strategies of Latin American neurosurgeons in treating BPI cases. In clinical cases, participants were asked about the indication for surgery, timing, and choice of different surgical strategies.

The general questions were formulated as follows:

1. How long ago did you finish your residency training?

2. Did you have any contact with brachial plexus patients during your residency training?

3. Where did you learn to operate on brachial plexus trauma cases?

4. What is the average number of brachial plexus reconstruction surgeries you perform yearly?

5. Do you operate on neonate brachial plexus trauma cases?

6. Are all your patients subjected to imaging studies (magnetic resonance imaging [MRI] or computed tomography [CT] myelography)?

7. Do you think electromyography is essential in all cases?

8. Do you apply electrophysiologic methods during surgery?

9. How long do you keep the operated arm immobilized?

10. Are you satisfied with the post-operative rehabilitation of your patients?

[Table 1] describes the clinical cases according to the way they were formulated.

Table 1 Clinical cases formulation

Case	Case description
1	An 18-year-old man was involved in a motor vehicle accident. Six weeks later, he was examined by a nerve surgeon, who found a complete loss of motility and sensibility in the entire right upper limb. A Horner syndrome was present. MRI revealed pseudomeningoceles in all nerve roots related to the brachial plexus. Associated neuropathic pain was also present.
2	A 25-year-old man was involved in a motorcycle accident. Four months post-injury, there were no contractions of the supraspinatus, infraspinatus, deltoid, or biceps muscles. Good motor function was observed distal to the elbow. MRI did not have any significant findings. Sensory nerve action potentials (SNAP) was absent from the median nerve.
3	A 28-year-old man collided his motorcycle with a wall and sustained a brachial plexus injury. Now, three months post-injury, there was good function of the muscles innervated by the superior and middle trunks, including abduction and external rotation of the shoulder, flexion and extension of the elbow, and pronation/supination of the forearm. Distal movements of the upper limb were missing. Horner syndrome was also observed. Imaging studies showed avulsion of the C-8 and T-1 nerve roots. Normal SNAP was observed in the ulnar nerve.
4	A 5-month-old infant with a neonatal brachial plexus palsy (NBPP) presented with a flail arm. The hand deficit recovered within 48 h of delivery and elbow extension within two months. Now, five months post-injury, complete paralysis of shoulder abduction/external rotation and elbow flexion was observed.

During the postoperative period, all patients had the operated limb immobilized in an arm sling. The sling use was interrupted after a certain time, and the patients were referred for rehabilitation.

 

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Results

Forty-six neurosurgeons, actively practicing peripheral nerve surgery in various Latin American countries were invited to participate in the survey. Twenty-three neurosurgeons from five countries (Brazil, Argentina, Uruguay, Mexico, and Colombia) agreed to participate, consolidating a response rate of 50% ([Table 2]).

Table 2 Neurosurgeons participants of the study

Participants	Country
Ana Lovaglio	Argentina
Carlos Rodriguez	Mexico
Dalton Senda	Brazil
Fernando Guedes	Brazil
Fernando Henrique Sousa	Brazil
Fernando Martinez	Uruguai
Flávio Leitão Filho	Brazil
Gilda Di Masi	Argentina
Gonzalo Bonilla	Argentina
Herbert Almeida	Brazil
Jules Dourado	Brazil
Kelia Santiago Dias	Brazil
Marcelo Magalhães	Brazil
Marcio Mendonça	Brazil
Mariano Socolovsky	Argentina
Mario Siqueira	Brazil
Marjeane Hockmüller	Brazil
Paulo Tavares	Brazil
Ricardo Gepp	Brazil
Ricardo Gonzalez	Colombia
Roberto Martins	Brazil
Samantha Pinazzo	Uruguai
Wilson Faglioni	Brazil

Three surgeons (13%) completed their residency training 5-9 years ago before this article was finished in November 2024, five (21%) 10-14 years before, and 15 (65.2%) ≥ 15 years before.

Only 43.4% of respondents had sufficient exposure to brachial plexus surgery during their residency training.

Five (13%) surgeons learned to operate on brachial plexus cases during the residency training. Fourteen (60.8%) participants learned it during fellowships, and four (17.3%) were instructed during residency and fellowship.

The average number of surgeries performed annually by each surgeon was 35.5 (range: 15–130).

Fifteen surgeons (65.2%) operated on neonate brachial plexus trauma cases.

The frequency of preoperative imaging depended on the type of financial support each patient had: private, social insurance, or publicly funded healthcare system. Fourteen surgeons (60.8%) would perform MRI on all patients, one (4.3%) only in the case of complete lesions, and two (8.6%) “whenever possible.” One surgeon would perform CT myelography in the absence of an MRI. Seven surgeons (30.4%) would perform MRIs only on private patients and with social insurance (20-60% of all patients). One surgeon (4.3%) would also rely on the information provided by the ultrasound of the brachial plexus, besides the MRI. Most participants who performed surgery for NBPP would ask for an MRI only when treating complete palsies.

Twenty surgeons (86.9%) would perform electromyography (EMG) in all patients. One (4.3%) indicated examination only in the case of partial lesions or when the evolution was poor, and another (4.3%) indicated it only in dubious cases. One of the surgeons did not indicate EMG for his patients. In NBPP injuries, EMG was not routinely performed in any survey respondents.

Almost all surgeons opted to use electrophysiological methods during surgery. Eighteen responders (78.2%) performed electrostimulation of the plexus. Three (13%) and two (8.6%) surgeons measured somatosensory-evoked potentials and nerve action potentials, respectively. Two participants (8.6%) did not use any intraoperative electrophysiology.

Nineteen responders (82.6%) advised immobilizing the affected limb in an arm sling for 21 days post-surgery. Three (13%) recommended 15 days, and another (4.3%) for 30 days.

Postoperative rehabilitation was considered “very good” by only two surgeons (8.6%). For eight surgeons (34.7%), it was adequate in 30% to 80% of patients. Most of these patients were either private or insured. The available rehabilitation was considered inadequate by 13 (56.5%) participants.

All surgeons agreed that Case 1 (adult complete brachial plexus palsy, probably with many root avulsions) should be operated on, and most (21, 91.3%) would perform the surgery immediately or as soon as possible. Spinal accessory to the suprascapular nerve transfer and phrenic-to-musculocutaneous nerve transfer were the most used techniques by 21 (91.3%) and 19 (82.6%) participants, respectively. On many occasions, those two techniques were combined. Many other surgical techniques were employed with or without combination with previously mentioned techniques: intercostobrachial to median nerve transfer (6 participants, 26%), intercostal to the long head of triceps branch transfer (4 participants, 17.3%), intercostal to biceps branch transfer (3 participants, 13%), scapula elevator branch to axillary nerve transfer (2 participants, 8.6%), and phrenic to posterior division of the upper trunk and medial pectoral to musculocutaneous nerve transfer (1 participant each, 4.3%). Three surgeons suggested microneurolysis might help treat these lesions (13%).

All surgeons indicated surgical treatment in Case 2 (adult C5-C6 lesion). Sixteen (69.5%) surgeons would operate as soon as possible, six (26%) would wait until six months, and one (4.3%) would perform the surgery between six and nine months. Seventeen participants (73.9%) suggested triple nerve transfer: a spinal accessory to the suprascapular nerve, a branch of the radial nerve innervating the triceps to the axillary nerve (Somsak procedure), and an ulnar nerve fascicle to the musculocutaneous branch to the biceps (Oberlin procedure). Ten (58.8%) participants suggested transferring a median nerve fascicle to the musculocutaneous branch of the brachialis to reinforce the reinnervation of the elbow flexion. Many other different nerve transfers were also indicated: four surgeons (17.3%) indicated spinal accessory to suprascapular nerve transfer, three surgeons (13%) indicated the Oberlin procedure plus spinal accessory nerve transfer, three (13%) indicated grafts from C5 to the posterior division of the upper trunk, two (8.6%) indicated simultaneous reinnervation of biceps and brachialis, and one each (4.3%) indicated medial pectoralis to axillary nerve transfer and median nerve fascicle to the musculocutaneous branch to the brachialis transfer. One surgeon also indicated microneurolysis for this type of lesion.

In Case 3 (probable avulsion of the C8 and T1 nerve roots), 19 (82.6%) of the survey participants indicated surgical treatment, while four (17.3%) considered the case to be non-surgical. Twelve surgeons (63%) showed that the operation should be performed as soon as possible, and seven (36%) indicated surgery ≥ 6 months post-injury. Transfer of the musculocutaneous branch from the brachialis to the anterior interosseous nerve was indicated by 13 (68.4%) participants. The second most indicated technique (nine participants, 47.3%) was branch transfer from the supinator to the posterior interosseous nerve, usually associated with the previously mentioned transfer. Many other different techniques were proposed; however, each one was applied by only one participant (5.2%).

Case 4 was a typical NBPP case: the so-called Erb's palsy (C5-C6/upper trunk lesion) in a five-month-old infant. Of the 23 participating surgeons, 15 (65.2%) routinely operated on neonates. Eight surgeons (53.3%) indicated surgery at six months of life, six (40%) at three months, and one (6.6%) at nine months. Most surgeons (8–53.3%) would reconstruct the upper plexus with grafts, C5 to the posterior division of the upper trunk and C6 to the anterior division of the upper trunk. Five surgeons (33.3%) indicated that spinal accessory nerve transfer should complement this approach. Triple nerve transfers were suggested by three participants (20%). Other transfer techniques were chosen by only one surgeon (6.6%).

 

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Discussion

Some physicians have a pessimistic attitude toward the surgical repair of BPI. This results in late referrals which cause patients to miss the best timing for primary nerve repair. Owing to the rarity of these lesions and their different clinical presentations, there is a lack of treatment protocols; consequently, the surgical repair of BPI differs among surgeons. This study aimed to determine the variability in strategies for the surgical repair of BPIs among Latin American neurosurgeons.

Mailed questionnaires are the most frequently used method for surveying physicians in health services; however, no gold standard exists for an acceptable response rate. Cummings et al.[3] found variations in response rates ranging from 40% to 80%, with an average of 61%. In addition, two recent studies,[1] [2] related explicitly to BPI surgery, reported response rates of 39% and 60.3% (average, 49.6%). The response rate of 50% in our survey falls within the expected rate for physician surveys, providing a representative picture of the group.

Only 43.4% of respondents reported adequate contact with brachial plexus surgery during residency training, similar to the results of Maniker and Passannante.[4] In a survey that included 1728 members of the American Association of Neurological Surgeons and the Congress of Neurological Surgeons, 48.7% of surgeons had sufficient exposure to peripheral nerve surgery during training. Considering that the community of brachial plexus surgeons is small about other surgical subspecialties,[5] the limited exposure detected in our survey reflects the few existing neurosurgical departments that routinely operate BPI in Latin American countries. Therefore, the small cohort presented in this study represents Latin American neurosurgeons performing brachial plexus surgery. The majority (78.1%) had learned to operate on BPI during fellowships.

In Case 1, all surgeons agreed that the patient should undergo surgery, and the majority (91.3%) would do so as soon as possible. In a systematic review of the timing of surgery for traumatic brachial plexus injury, Martin et al.[6] demonstrated that 65.5% of the patients underwent surgery within six months and 27.4% within three months. The results of the earlier surgery were better. Extraplexal nerve transfers were performed in all cases. Although Socolovsky et al[7] demonstrated recently that patients with a previous phrenic nerve transfer tolerated acute COVID-19 infection well, this nerve transfer was not used during the pandemic due to fear of pulmonary complications.

In Case 2, there was again a consensus on the indications for surgical treatment. Concerning surgical timing, most participants wanted to operate as soon as possible (69.5%) or after six months (26%). Triple nerve transfer was the most common surgical strategy (73.9%). Ten participants considered transferring the median nerve fascicle to the brachialis branch of the musculocutaneous nerve to reinforce elbow flexion. Nerve transfers were initially described for the treatment of peripheral nerve injuries. However, they have also been indicated for brachial plexus lesions in recent years. The advantages of nerve transfers include reducing the distance between the donor and the target and reducing surgical time, risk, and technical demand. Clinical outcomes indicate the efficacy and reliability of these procedures, especially for lesions in the upper elements of the plexus.[8] [9] [10]

Four respondents (17.3%) considered Case 3, an avulsion lesion of C8 and T1 nerve roots, nonsurgical. Twelve surgeons (63%) would operate on this injury as soon as possible, and seven (36%) preferred to wait six or more months after the trauma. The most recommended surgical approach was distal nerve transfer. Interestingly, none of the surgeons surveyed reported the necessity to expose C8-T1 lesions surgically. Concerns about the technical difficulty and unfavorable risk benefits discourage most surgeons from exploring lower trunk injuries.[5] Transfer of the brachialis nerve to the anterior interosseous nerve[11] is the most used nerve transfer method (68.4% of cases), followed by the transfer of a supinator branch to the posterior interosseous nerve[12] in 47.3% of patients with this type of lesion. In many cases, these two techniques have been combined.

Eight surgeons (34.7%) did not operate on infants (Case 4). Among those performing this type of surgery, nine (60%) preferred to operate when the infant was ≥ six months-old, and six (40%) when three months-old. Eight surgeons (53.3%) preferred reconstructing of the brachial plexus with grafts. Seven participants (46.6%) indicated nerve transfers.

Protective sensation in the upper extremity is vital for limb survival. Without sensation, the extremities are likely to be subjected to repeated trauma and eventually, infection. Even so, only six surgeons (26%) attempted to reinnervate the sensation in the hand. All surgeons applied the intercostobrachial nerve to the lateral contribution to the median nerve transfer technique.[13] [14]

It is widely accepted that postoperative rehabilitation (physical and occupational therapy) is essential for the success of brachial plexus surgery. Unfortunately, rehabilitation programs for BPI are inadequate in most Latin American countries, especially in publicly funded healthcare systems. Only two surgeons working in a famous rehabilitation hospital qualified their program as “very good.” Others could get adequate postoperative rehabilitation in only a small percentage of social security and private cases.

The most important limitation of this study was its small sample size, but attention should also be paid to possible selection bias. Most of the survey participants are independent surgeons, without the support of a multidisciplinary center for the treatment of brachial plexus injuries, who were trained by one of the well-recognized groups that participated in the survey. This fact, associated with frequent contact at scientific meetings, is probably responsible for the high degree of agreement in the survey results.

However, this should not be interpreted as a potential standardization of strategies, because broader studies involving specialists from different parts of the world demonstrated substantial disagreement in treatment strategies for brachial plexus injuries.[1] [2] [15]

Latin America requires more centers for brachial plexus surgery, more resources for preoperative evaluations in patients with publicly funded healthcare systems, and better rehabilitation programs.

 

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Conclusions

This study investigated the management of different types of BPIs by a multinational group of neurosurgeons with experience in peripheral nerve surgery. Most surgeons indicated surgery, and the majority preferred to operate early in adult cases. In neonates, most surgeons preferred waiting until six months of age.

Nerve transfer was the primary technique performed in adults. However, in neonates, there was a tendency to perform more grafts than transfers.

Disagreements about the surgical strategy in many situations reflect the need for prospective randomized studies to determine the merits of each form of treatment.

Although new options for managing BPI continue to appear, the relatively low number of cases and the complexity of each injury make it challenging to prepare guidelines for clinical practice.

 

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No conflict of interest has been declared by the author(s).

Acknowledgment

We thank all neurosurgeons who participated in this study.

Author Contributions

Conception and design of the study - MGS, MS; Acquisition of data - MGS, MS, RSM, GDM; Analysis and interpretation of data - MGS, MS, RSM, GDM; Drafting and revision the article – MGS, MS; Final approval of the version to be submitted – MGS, MS, RSM, GDM.

Declaration of Interest

The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.

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Publication History

Received: 13 November 2024

Accepted: 20 March 2025

Article published online:
16 July 2025