Functional and morphological evaluation of the trapezius muscle after spinal accessory nerve transfer to brachial plexus nerves.

INTRODUCTION: The main innervation of the trapezius muscle is provided by the spinal accessory nerve. Several studies describe the contributions of cervical plexus roots to the trapezius muscle innervation, either directly or through connections with the spinal accessory nerve. There is no adequate understanding of how the trapezius muscle is affected after using the spinal accessory nerve in nerve transfer procedures with the usual technique, preserving at least 1 branch for the upper trapezius. METHODS: We evaluated 20 patients with sequelae of traumatic brachial plexus injury who underwent surgical procedures for brachial plexus repair or free muscle transfer, which included the spinal accessory nerve transfer technique and were followed for a minimum of 1 year. The three portions trapezius muscle were evaluated by physical examination, magnetic resonance imaging (analysis of fatty degeneration) and electromyography. RESULTS: In all evaluation methods, the middle and lower portions of the trapezius muscle showed more significant morphological and/or functional impairment than the upper portion, in most cases. There was a statistically significant difference in all the complementary exams results, between the affected side (with sacrifice of the nerve) versus the normal side, in the middle and lower portions of the trapezius muscle. CONCLUSIONS: Physical examination alone is not sufficient to determine the residual functionality of the trapezius muscle. Magnetic resonance imaging and electromyography are useful tools to assess both morphological involvement of the trapezius muscle and nerve conduction impairment of the trapezius muscle, respectively. The results suggest that the middle and lower portions of the trapezius muscle are affected by previous SAN transfer and should be considered with caution for further muscle transfer procedures.

Congenital myasthenic syndrome: Correlation between clinical features and molecular diagnosis.

OBJECTIVES: To present phenotype features of a large cohort of congenital myasthenic syndromes (CMS) and correlate them with their molecular diagnosis. METHODS: Suspected CMS patients were divided into three groups: group A (limb, bulbar or axial weakness, with or without ocular impairment, and all the following: clinical fatigability, electrophysiology compatible with neuromuscular junction involvement and anticholinesterase agents response), group B (limb, bulbar or axial weakness, with or without ocular impairment, and at least one of additional characteristics noted in group A) and group C (pure ocular syndrome). Individual clinical findings and the clinical groups were compared between the group with a confirmed molecular diagnosis of CMS and the group without molecular diagnosis or with a non-CMS molecular diagnosis. RESULTS: Seventy-nine patients (68 families) were included in the cohort: 48 in group A, 23 in group B and 8 in group C. Fifty-one were considered confirmed CMS (30 CHRNE, 5 RAPSN, 4 COL13A1, 3 DOK7, 3 COLQ, 2 GFPT1, 1 CHAT, 1 SCN4A, 1 GMPPB, 1 CHRNA1), 7 probable CMS, 5 non-CMS and 16 unsolved. The chance of a confirmed molecular diagnosis of CMS was significantly higher for group A and lower for group C. Some individual clinical features, alterations on biopsy and electrophysiology enhanced specificity for CMS. Muscle imaging showed at least mild alterations in the majority of confirmed cases, with preferential involvement of soleus, especially in CHRNE CMS. CONCLUSIONS: Stricter clinical criteria increase the chance of confirming a CMS diagnosis, but may lose sensitivity, especially for some specific genes.

Restoration of shoulder external rotation by means of the infraspinatus muscle reinnervation with a radial nerve branch transfer.

Background: Although reinnervation of the suprascapular nerve is frequently obtained through brachial plexus surgery, reestablishment of infraspinatus muscle function is rarely achieved.Methods: The viability of transfer of the radial nerve to the nerve branch to the infraspinatus muscle was determined anatomically, including histomorphometrical analysis on 30 adult cadavers. Eleven adult patients were then treated using the proposed nerve transfer.Results: The branch to the medial head was more suitable for the nerve transfer. In one cadaver, nerve transfer was impossible because there was no donor of sufficient length. According to axon counts, the branches to the lateral and medial heads had sufficient numbers of axons (means = 994.2 ± 447.6 and 1030.8 ± 258.5, respectively) for reinnervation of the branch to the infraspinatus (means = 830.2 ± 241.2 axons). In the surgical series, one patient was lost in the follow-up and only two patients achieved a good result from the transfer. Recovery of external shoulder rotation started 14 months after surgery in one patient and 8 months in the other. The first patient reached 90° of external rotation 6 months later and the second, achieved 120°of shoulder external rotation 6 months after surgery . Four other patients recovered small amounts of movement: 20, 35, 40 and 45°.Conclusions: Although anatomically feasible, the proposed nerve transfer resulted in a small number of good clinical outcomes.

Functional outcome of spinal accessory nerve transfer to the suprascapular nerve to restore shoulder function: Results in upper and complete traumatic brachial plexus palsy in adults.

BACKGROUND: Shoulder stability, abduction and external rotation are vital for the performance of usual daily tasks. AIMS: To compare the functional outcomes in the shoulder following spinal accessory to suprascapular nerve transfer (SASNT). PATIENTS AND METHODS: Comparison of the outcome of adult patients with upper traumatic brachial plexus palsy undergoing SASNT with patients with complete palsy submitted to the same procedure. STATISTICAL ANALYSIS: Ranges of motion were compared via the Mann-Whitney U test. The percentages of patients with a favorable outcome were compared by the chi-square test. All tests were two-tailed and P values <0.05 were considered statistically significant. RESULTS: SASNT was performed in 76 patients: 23 cases (30.2%) of upper-plexus injuries and 53 cases (69.7%) of complete brachial plexus palsy. Good shoulder abduction was achieved in 15 patients (65.2%) with upper plexus palsy and a good external rotation in 5 (21.7%). In those patients with a good recovery, the average range of motion (ROM) was 53° for shoulder abduction and 71.2° for external rotation. Thirty-six patients (67.9%) with complete palsy had a good shoulder abduction recovery with 30.7° of average ROM, but only 3 patients (5.6%) recovered a good shoulder external rotation with 68.3° of average ROM. There was no statistical difference for the abduction outcome, but the external rotation outcome was superior in the upper plexus palsy group. CONCLUSION: SASNT is a consistent procedure to achieve functional recovery of shoulder abduction after a partial or complete plexus injury, but the outcomes of external rotation were quite disappointing in both the groups.

Distal nerve transfer versus supraclavicular nerve grafting: comparison of elbow flexion outcome in neonatal brachial plexus palsy with C5-C7 involvement.

PURPOSE: Ulnar and median nerve transfers to arm muscles have been used to recover elbow flexion in infants with neonatal brachial plexus palsy, but there is no direct outcome comparison with the classical supraclavicular nerve grafting approach. METHODS: We retrospectively analyzed patients with C5-C7 neonatal brachial plexus palsy submitted to nerve surgery and recorded elbow flexion recovery using the active movement scale (0-7) at 12 and 24 months after surgery. We compared 13 patients submitted to supraclavicular nerve grafting with 21 patients submitted to distal ulnar or median nerve transfer to biceps motor branch. We considered elbow flexion scores of 6 or 7 as good results. RESULTS: The mean elbow flexion score and the proportion of good results were better using distal nerve transfers than supraclavicular grafting at 12 months (p < 0.01), but not at 24 months. Two patients with failed supraclavicular nerve grafting at 12 months showed good elbow flexion recovery after ulnar nerve transfers. CONCLUSION: Distal nerve transfers provided faster elbow flexion recovery than supraclavicular nerve grafting, but there was no significant difference in the outcome after 24 months of surgery. Patients with failed supraclavicular grafting operated early can still benefit from late distal nerve transfers. Supraclavicular nerve grafting should remain as the first line surgical treatment for children with neonatal brachial plexus palsy.

Prognostic value of thumb pain sensation in birth brachial plexopathy.

OBJECTIVE: To evaluate the prognostic value of absent thumb pain sensation in newborns and young infants with birth brachial plexopathy. METHODS: We evaluated 131 patients with birth brachial plexopathy with less than two months of age. Pain sensation was evoked by thumb nail bed compression to evaluate sensory fibers of the upper trunk (C6). The patients were followed-up monthly. Patients with less than antigravity elbow flexion at six months of age were considered to have a poor outcome. RESULTS: Thirty patients had absent thumb pain sensation, from which 26 showed a poor outcome. Sensitivity of the test was 65% and specificity was 96%. CONCLUSION: Evaluation of thumb pain sensation should be included in the clinical assessment of infants with birth brachial plexopathy.

Prognostic value of thumb pain sensation in birth brachial plexopathy / Valor prognóstico da sensibilidade dolorosa do polegar na plexopatia braquial relacionada ao parto

OBJECTIVE: To evaluate the prognostic value of absent thumb pain sensation in newborns and young infants with birth brachial plexopathy. METHODS: We evaluated 131 patients with birth brachial plexopathy with less than two months of age. Pain sensation was evoked by thumb nail bed compression to evaluate sensory fibers of the upper trunk (C6). The patients were followed-up monthly. Patients with less than antigravity elbow flexion at six months of age were considered to have a poor outcome. RESULTS: Thirty patients had absent thumb pain sensation, from which 26 showed a poor outcome. Sensitivity of the test was 65% and specificity was 96%. CONCLUSION: Evaluation of thumb pain sensation should be included in the clinical assessment of infants with birth brachial plexopathy.

OBJETIVO: Avaliar o valor prognóstico da hipoestesia dolorosa no polegar em recém-nascidos e lactentes jovens com plexopatia braquial obstétrica. MÉTODOS: Avaliamos 131 pacientes com plexopatia braquial obstétrica com menos de dois meses de idade. A sensação dolorosa foi provocada pela compressão do leito ungueal do polegar para avaliar fibras sensitivas do tronco superior (C6). Os pacientes foram seguidos mensalmente. Prognóstico desfavorável foi atribuído aos pacientes sem força antigravitacional para flexão do cotovelo aos seis meses de idade. RESULTADOS: Trinta pacientes apresentaram hipoestesia dolorosa do polegar, dos quais 26 tiveram prognóstico desfavorável. A sensibilidade do teste foi de 65% e a especificidade 96%. CONCLUSÃO: A avaliação da sensibilidade dolorosa do polegar deve ser incluída na avaliação clínica de pacientes com plexopatia braquial obstétrica.

Management of desmoid-type fibromatosis involving peripheral nerves.

Desmoid-type fibromatosis is an uncommon and aggressive neoplasia, associated with a high rate of recurrence. It is characterized by an infiltrative but benign fibroblastic proliferation occurring within the deep soft tissues. There is no consensus about the treatment of those tumors. We present a surgical series of four cases, involving the brachial plexus (two cases), the median nerve and the medial brachial cutaneous nerve. Except for the last case, they were submitted to multiple surgical procedures and showed repeated recurrences. The diagnosis, the different ways of treatment and the prognosis of these tumoral lesions are discussed. Our results support the indication of radical surgery followed by radiotherapy as probably one of the best ways to treat those controversial lesions.

Management of desmoid-type fibromatosis involving peripheral nerves / Tratamento da fibromatose tipo desmoide envolvendo nervos periféricos

Desmoid-type fibromatosis is an uncommon and aggressive neoplasia, associated with a high rate of recurrence. It is characterized by an infiltrative but benign fibroblastic proliferation occurring within the deep soft tissues. There is no consensus about the treatment of those tumors. We present a surgical series of four cases, involving the brachial plexus (two cases), the median nerve and the medial brachial cutaneous nerve. Except for the last case, they were submitted to multiple surgical procedures and showed repeated recurrences. The diagnosis, the different ways of treatment and the prognosis of these tumoral lesions are discussed. Our results support the indication of radical surgery followed by radiotherapy as probably one of the best ways to treat those controversial lesions.

A fibromatose do tipo desmoide é uma lesão tumoral agressiva e rara, associada a alto índice de recorrência. É caracterizada pela fibroblástica infiltrativa, porém benigna, que ocorre no interior de tecidos moles profundos. Não existe consenso com relação ao tratamento desses tumores. Apresentamos uma série cirúrgica de quatro casos comprometendo o plexo braquial (dois casos), o nervo mediano e o nervo cutâneo medial do braço. Com exceção do último caso, todos foram submetidos a múltiplos procedimentos cirúrgicos e apresentaram recorrências repetidas. São discutidos o diagnóstico, as diferentes formas de tratamento e o prognóstico dessas lesões tumorais. Nossos resultados apoiam o conceito de que cirurgia radical seguida por radioterapia é uma das melhores formas de se tratar essas controvertidas lesões.

Motor nerve-conduction studies in obstetric brachial plexopathy for a selection of patients with a poor outcome.

BACKGROUND: The criteria and timing for nerve surgery in infants with obstetric brachial plexopathy remain controversial. Our aim was to develop a new method for early prognostic assessment to assist this decision process. METHODS: Fifty-four patients with unilateral obstetric brachial plexopathy who were ten to sixty days old underwent bilateral motor-nerve-conduction studies of the axillary, musculocutaneous, proximal radial, distal radial, median, and ulnar nerves. The ratio between the amplitude of the compound muscle action potential of the affected limb and that of the healthy side was called the axonal viability index. The patients were followed and classified in three groups according to the clinical outcome. We analyzed the receiver operating characteristic curve of each index to define the best cutoff point to detect patients with a poor recovery. RESULTS: The best cutoff points on the axonal viability index for each nerve (and its sensitivity and specificity) were <10% (88% and 89%, respectively) for the axillary nerve, 0% (88% and 73%) for the musculocutaneous nerve, <20% (82% and 97%) for the proximal radial nerve, <50% (82% and 97%) for the distal radial nerve, and <50% (59% and 97%) for the ulnar nerve. The indices from the proximal radial, distal radial, and ulnar nerves had better specificities compared with the most frequently used clinical criterion: absence of biceps function at three months of age. CONCLUSIONS: The axonal viability index yields an earlier and more specific prognostic estimation of obstetric brachial plexopathy than does the clinical criterion of biceps function, and we believe it may be useful in determining surgical indications in these patients.

Clinical-electromyography correlation in infants with obstetric brachial plexopathy.

PURPOSE: The real utility of needle electromyography (EMG) for evaluation of infants with obstetric brachial plexopathy remains controversial. The objective of this paper is to evaluate how EMG correlates with clinical evaluation of these patients. METHODS: We performed EMG in 41 infants (42 arms) with severe obstetric brachial plexopathy who were from 3 to 12 months of age. We correlated the EMG interference pattern with the clinical assessment of infraspinatus, deltoid, biceps, triceps, and extensor digitorum communis muscles. RESULTS: Motor unit potentials were always present, and abnormal spontaneous activity was not common in proximal muscles. The correlation between EMG interference pattern and clinical assessment was not good, except for extensor digitorum communis. EMG showed higher scores than clinical evaluation for infraspinatus, deltoid, and biceps muscles. Respiratory synkinesis was present in 19 patients, or 45% of the affected arms, and it could involve any muscle innervated from C5 to T1. CONCLUSIONS: Needle EMG fails to estimate or overestimates clinical recovery in proximal muscles in this age group.

Prognostic relevance of risk factors for obstetrical brachial plexopathy.

We did a case-control study to verify if the birthweight, forceps delivery or perinatal asphyxia have any significant effect on the prognosis of obstetrical brachial plexopathy. Group A was composed of 25 infants who completely recovered at the age of 6 months. Group B was composed of 21 infants who were still not able to remove a blindfold from the face with the affected limb in the sitting position at the age of 12 months. There was no statistical difference of the median birthweight or median first minute Apgar score between the groups. There was also no relation between birthweight higher than 4000 g, first minute Apgar score lower than 6 or forceps delivery with a poor prognosis.

Prognostic relevance of risk factors for obstetrical brachial plexopathy

Realizamos um estudo caso-controle para verificar se o peso ao nascimento, parto forceps ou asfixia perinatal apresentam efeito significativo no prognóstico da plexopatia braquial obstétrica. O grupo A foi composto por 25 lactentes que apresentavam recuperação completa aos 6 meses de idade. O grupo B foi composto por 21 lactentes incapazes de remover uma venda do rosto com o membro acometido na posição sentada aos 12 meses de idade. Não houve diferença significativa entre as medianas de peso ao nascimento ou do boletim Apgar do primeiro minuto entre os grupos. Também não foi observada relação entre peso ao nascimento maior que 4000g, boletim Apgar do primeiro minuto menor do que 6 ou parto forceps com um prognóstico desfavorável.

Mixed latency difference for diagnosis of ulnar neuropathy at the elbow.

OBJECTIVE: To provide reference values and to compare this technique with the standard motor conduction velocity (MCV) of the ulnar nerve. DESIGN: Retrospective unmasked study. SETTING: Private and institutional practice. PARTICIPANTS: The reference group included 57 healthy volunteers. Patients included 100 subjects with suspected ulnar neuropathy at the elbow (UNE) referred for neurophysiologic evaluation. This group was subdivided into 2 groups: group A was composed of 45 patients with UNE confirmed by MCV of the ulnar nerve, and group B included 55 patients with suspected UNE in whom the diagnosis could not be established by MCV of the ulnar nerve. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Differences between peak latencies of ulnar and median mixed nerve action potentials at the arm, after stimulating these nerves at the wrist. This was called mixed latency difference. RESULTS: The upper normative limit of the mixed latency difference was 1.1 ms, and there was a significant correlation with height. In group A, the mixed latency difference was abnormal in 80% of the cases and could not be calculated in 18%. In group B, the mixed latency difference was abnormal in 8 (15%) patients. All of these had abnormal "inching" of the ulnar nerve across the elbow. CONCLUSIONS: The mixed latency difference was particularly useful in cases of mild UNE.

Botulinum toxin for treatment of cocontractions related to obstetrical brachial plexopathy.

Botulinum toxin type A was recently introduced for treatment of biceps-triceps muscle cocontraction, which compromises elbow function in children with obstetrical brachial plexopathy. This is our preliminary experience with this new approach. Eight children were treated with 2-3 U/kg of botulinum toxin injected in the triceps (4 patients) and biceps (4 patients) muscle, divided in 2 or 3 sites. All patients submitted to triceps injections showed a long-lasting improvement of active elbow flexion and none required new injections, after a follow-up of 3 to 18 months. Three of the patients submitted to biceps injections showed some improvement of elbow extension, but none developed anti-gravitational strength for elbow extension and the effect lasted only three to five months. One patient showed no response to triceps injections. Our data suggest that botulinum toxin can be useful in some children that have persistent disability secondary to obstetrical brachial plexopathy.

Botulinum toxin for treatment of cocontractions related to obstetrical brachial plexopathy

A toxina botulínica do tipo A foi introduzida recentemente para o tratamento das co-contrações entre os músculos biceps e triceps, que comprometem a função do cotovelo nas crianças com plexopatia braquial obstétrica. Apresentamos nossa experiência preliminar com esta abordagem. Oito crianças foram tratadas com 2 - 3 U/kg de toxina botulínica injetada nos músculos triceps (4 pacientes) e biceps (4 pacientes), divididas em 2 ou 3 sítios. Todos os pacientes submetidos a injeções no triceps apresentaram melhora persistente da flexão do cotovelo e nenhum precisou de novas aplicações após seguimento de 3 a 18 meses. Três pacientes submetidos a aplicações no biceps apresentaram melhora na extensão do cotovelo, mas nenhum adquiriu força antigravitacional e o efeito durou apenas 3 a 5 meses. Um paciente não respondeu às injeções. Nossos dados sugerem que a toxina botulínica pode ser útil no tratamento de algumas crianças com seqüelas de plexopatia braquial obstétrica.

Motor conduction studies for prognostic assessment of obstetrical plexopathy.

Early prognostic assessment of obstetrical brachial plexopathies (OBP) would facilitate rational selection of infants for brachial plexus surgery. We performed bilateral motor nerve conduction studies (MNCS) of axillary, musculocutaneous, radial, median, and ulnar nerves in 33 babies (age 10-60 days) with OBP in order to compare the amplitude of compound muscle action potentials (CMAPs). All babies were followed up until 6 months of age and the outcome was classified according to muscle strength and arm function. A CMAP amplitude reduction of more than 90%, compared to the unaffected side, predicted severe weakness of the corresponding root level (p < 0.01). Our results indicate that MNCS are a useful tool for very early prognostic assessment of OBP.

Treatment of febrile seizures with intermittent clobazam

Fifty children, 24 female and 26 male, with ages varying from 6 to 72 months (mean=23.7 m.) that experienced at least one febrile seizure (FS) entered a prospective study of intermittent therapy with clobazam. Cases with severe neurological abnormalities, progressive neurological disease, afebrile seizures, sympromatic seizures of other nature, or seizures during a central nervous system infection were excluded. Seizures were of the simple type in 25 patients, complex in 20 and unclassified in 5. The mean follow-up period was 7.9 months (range=1 to 23 m.), and the age at the first seizure varied from 5 to 42 months (mean=16.8 m.). Clobazam was administered orally during the febrile episode according to the child's weight: up to 5 kg, 5 mg/day; from 5 to 10 kg, 10 mg/day; from 11 to 15 kg, 15 mg/day, and over 15 kg, 20 mg/day. There were 219 febrile episodes, with temperature above 37.8 degrees Celsius, in 40 children during the study period. Twelve children never received clobazam and 28 received the drug at least once. Drug efficacy was measured by comparing FS recurrence in the febrile episodes that were treated with clobazam with those in which only antipyretic measures were taken. Ten children (20 percent) experienced a FS during the study period. Of the 171 febrile episodes treated with clobazam there were only 3 recurrences (1.7 percent), while of the 48 episodes treated only with antipyretic measures there were 11 recurrences (22.9 percent), a difference highly significant (p<0.0001). Adverse effects occurred in 10/28 patients (35.7 percent), consisting maily in vomiting, somnolene and hyperactivity. Only one patient had recurrent vomiting which lead to drug interruption. These effects did not necessarily ocurred in every instance the drug was administered, being present in one febrile episode and not in the others. We conclude that clonazepam is safe and efficacious in preventing FS recurrence. It may be an alternative to deazepam in the intermittent treatment of FS recurrence.