Anatomical study of the brachial plexus in human fetuses and its relation with neonatal upper limb paralysis / Estudo anatômico do plexo braquial de fetos humanos e sua relação com paralisias neonatais do membro superior

ABSTRACT Objective To study the anatomy of the brachial plexus in fetuses and to evaluate differences in morphology during evolution, or to find anatomical situations that can be identified as the cause of obstetric paralysis. Methods Nine fetuses (12 to 30 weeks of gestation) stored in formalin were used. The supraclavicular and infraclavicular parts of the brachial plexus were dissected. Results In its early course, the brachial plexus had a cord-like shape when it passed through the scalene hiatus. Origin of the phrenic nerve in the brachial plexus was observed in only one fetus. In the deep infraclavicular and retropectoralis minor spaces, the nerve fibers of the brachial plexus were distributed in the axilla and medial bicipital groove, where they formed the nerve endings. Conclusion The brachial plexus of human fetuses presents variations and relations with anatomical structures that must be considered during clinical and surgical procedures for neonatal paralysis of the upper limbs.

RESUMO Objetivo Estudar a anatomia do plexo braquial em fetos e avaliar diferenças de morfologia durante a evolução, ou encontrar situações anatômicas que possam ser apontadas como causa de paralisias obstétricas. Métodos Foram utilizados nove fetos formolizados entre 12 a 30 semanas de gestação e submetidos à dissecação supra e infraclavicular do plexo braquial. Resultados O plexo braquial inicialmente tem formato de cordão durante sua passagem pelo hiato dos escalenos e em apenas um feto foi observada a origem do nervo frênico por meio do plexo braquial. Na região infraclavicular profunda e retropeitoral menor, os fascículos do plexo braquial se distribuíam na axila e sulco bicipital medial para a formação dos nervos terminais. Conclusão O plexo braquial de fetos humanos apresenta variações e relações com estruturas anatômicas que devem ser consideradas durante os procedimentos clínicos e cirúrgicos das paralisias neonatais do membro superior.

Does primary brachial plexus surgery alter palliative tendon transfer surgery outcomes in children with obstetric paralysis?

BACKGROUND: The surgical management of obstetrical brachial plexus palsy can generally be divided into two groups; early reconstructions in which the plexus or affected nerves are addressed and late or palliative reconstructions in which the residual deformities are addressed. Tendon transfers are the mainstay of palliative surgery. Occasionally, surgeons are required to utilise already denervated and subsequently reinnervated muscles as motors. This study aimed to compare the outcomes of tendon transfers for residual shoulder dysfunction in patients who had undergone early nerve surgery to the outcomes in patients who had not. METHODS: A total of 91 patients with obstetric paralysis-related shoulder abduction and external rotation deficits who underwent a modified Hoffer transfer of the latissimus dorsi/teres major to the greater tubercle of the humerus tendon between 2002 and 2009 were retrospectively analysed. The patients who had undergone neural surgery during infancy were compared to those who had not in terms of their preoperative and postoperative shoulder abduction and external rotation active ranges of motion. RESULTS: In the early surgery groups, only the postoperative external rotation angles showed statistically significant differences (25 degrees and 75 degrees for total and upper type palsies, respectively). Within the palliative surgery-only groups, there were no significant differences between the preoperative and postoperative abduction and external rotation angles. The significant differences between the early surgery groups and the palliative surgery groups with total palsy during the preoperative period diminished postoperatively (p < 0.05 and p > 0.05, respectively) for abduction but not for external rotation. Within the upper type palsy groups, there were no significant differences between the preoperative and postoperative abduction and external rotation angles. CONCLUSIONS: In this study, it was found that in patients with total paralysis, satisfactory shoulder abduction values can be achieved with tendon transfers regardless of a previous history of neural surgery even if the preoperative values differ.

Classification of impairment of shoulder abduction in obstetric brachial plexus palsy and its clinical significance.

Shoulder abduction was studied in 25 cases of obstetric brachial plexus palsy (OBPP). According to muscle function, electromyographic features and X-ray examination, impairment of shoulder abduction could be classified into dynamic, resistant or combined types. Five cases were the dynamic type, which was characterized by paralysis of the shoulder abductors. Fifteen cases were categorized as the resistant type, with contracture of the subscapularis muscle, co-contraction of latissimus dorsi and teres major muscles and secondary disorders of the shoulder joint. Five cases were classified as the combined type in which there were both dynamic and resistant factors. Appropriate management and surgical procedures in the shoulder affected by OBPP depend on the pathological classification.

Imaging the brachial plexus and peripheral nerves in infants and children.

Imaging of the brachial plexus and peripheral nerves is challenging in the pediatric patient. Magnetic resonance imaging is the modality of choice as it is not invasive and demonstrates proximal and distal lesions. This may be used to detect nerve root avulsions, nerve ruptures, pseudo-meningoceles, brachial plexus scarring, post-traumatic neuromas, brachial plexus edema, spinal cord damage, abnormalities of the shoulder joint, trauma, neoplasms, and infection. Imaging allows diagnosis and careful preoperative evaluation of children suffering from brachial plexus injuries and peripheral nerve disorders.

[Congenital paralysis due to compression. Apropos of 4 cases]. / Paralysies congénitales par compression. A propos de quatre observations.

Four cases of congenital dysfunction of major peripheral nerves are reported and discussed. The first patient was a girl born by spontaneous delivery with an area of skin and muscle necrosis on the dorsal aspect of the forearm and a palsy of the three major nerves of the upper limb. The second patient was a boy born by caesarean section with the same necrotic lesions and a palsy of the ulnar and median nerve. The third patient was a boy born uneventfully with a truncal lesion of the sciatic nerve at the thigh. The fourth who was delivered by caesarean section for alteration of the monitoring presented a severe strangulation of the arm by the umbilical cord with palsy of the radial and ulnar nerve. The palsies recovered spontaneously and the sequelae are mostly due to the muscle necrosis. Congenital dysfunction of major peripheral nerves have been described as a complication of congenital constriction band syndrome, in association with subcutaneous fat necrosis, neonatal gangrene or aplasia cutis congenita. Intrauterine compression of a limb may be favoured by decreased foetal activity, by spontaneous rupture of the amniotic sac, particularly if there is a delay in delivery and by abnormal uterine activity during labour. Our three first cases confirm that the compression may arise before the labour. The fourth demonstrates that umbilical cord strangulation may lead to anoxia of the foetus together with compression of the limb.

Indications and results of brachial plexus surgery in obstetrical palsy.

This article presents the first series with long-term results of a large number of patients. As a result, it is difficult to compare these results with anything but spontaneous recovery. In most cases, the end result after surgical treatment will be better than spontaneous recovery.

The unusual features of traumatic neurogenic muscular atrophy in the infant: an anatomic study.

A biopsy from the deltoid muscle of an 8-week old girl who had sustained a bilateral traumatic Erb's brachial plexus paresis at birth revealed the neurogenic atrophy to be different from that of adult muscle in that small, round fibers, similar to those observed in Werdnig-Hoffmann disease, were found. Detailed histochemistry of the fibers is submitted. On electron microscopy, there was focal degeneration of sarcomeres; a loss of myofibrils and myofilaments accompanied by increased autophagocytosis and increased amounts of glycogen; occasionally, preferential drop out of thick myofilaments and a peculiar displacement and deformation of the T-system, triads. In spite of the fact that the injury was sustained at one well defined point of time, the degree to which the muscle fibers were affected was quite variable from area to area. It is proposed that denervation in infantile muscle results in typical small rounded fibers and that this process, so different from that of adult neurogenic atrophy, is age-dependent.