Anatomical study of the brachial plexus in human fetuses and its relation with neonatal upper limb paralysis.

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.

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.

Coracoid abnormalities and their relationship with glenohumeral deformities in children with obstetric brachial plexus injury.

BACKGROUND: Patients with incomplete recovery from obstetric brachial plexus injury (OBPI) usually develop secondary muscle imbalances and bone deformities at the shoulder joint. Considerable efforts have been made to characterize and correct the glenohumeral deformities, and relatively less emphasis has been placed on the more subtle ones, such as those of the coracoid process. The purpose of this retrospective study is to determine the relationship between coracoid abnormalities and glenohumeral deformities in OBPI patients. We hypothesize that coracoscapular angles and distances, as well as coracohumeral distances, diminish with increasing glenohumeral deformity, whereas coracoid overlap will increase. METHODS: 39 patients (age range: 2-13 years, average: 4.7 years), with deformities secondary to OBPI were included in this study. Parameters for quantifying coracoid abnormalities (coracoscapular angle, coracoid overlap, coracohumeral distance, and coracoscapular distance) and shoulder deformities (posterior subluxation and glenoid retroversion) were measured on CT images from these patients before any surgical intervention. Paired Student t-tests and Pearson correlations were used to analyze different parameters. RESULTS: Significant differences between affected and contralateral shoulders were found for all coracoid and shoulder deformity parameters. Percent of humeral head anterior to scapular line (PHHA), glenoid version, coracoscapular angles, and coracoscapular and coracohumeral distances were significantly lower for affected shoulders compared to contralateral ones. Coracoid overlap was significantly higher for affected sides compared to contralateral sides. Significant and positive correlations were found between coracoscapular distances and glenohumeral parameters (PHHA and version), as well as between coracoscapular angles and glenohumeral parameters, for affected shoulders. Moderate and positive correlations existed between coracoid overlap and glenohumeral parameters for affected shoulders. On the contrary, all correlations between the coracoid and glenohumeral parameters for contralateral shoulders were only moderate or relatively low. CONCLUSIONS: These results indicate that the spatial orientation of the coracoid process differs significantly between affected and contralateral shoulders, and it is highly correlated with the glenohumeral deformity. With the progression of glenohumeral deformity, the coracoid process protrudes more caudally and follows the subluxation of the humeral head which may interfere with the success of repositioning the posteriorly subluxed humeral head anteriorly to articulate with the glenoid properly.

The analysis of the intra-surgical view of the obstetric brachial plexus palsy.

The surgical intervention is necessary in about 20% of all cases of the perinatal brachial plexus palsy. In this study the intra-surgical view and the applied microsurgical techniques were analysed. The clinical material consisted of 49 children with the obstetric brachial plexus palsy treated operatively, on which the following changes were found intra-surgically: compression of the brachial plexus in 21 cases and injuries with discontinuity of the elements of the brachial plexus in 28 cases. The following surgical procedures were performed: neurolysis - 31 cases, direct neurorrhaphy - 7 cases, 2 - 4 sural nerve grafting from 2 to 3 cm - 4 cases, extra-anatomical extra-plexual reconstruction - 6 cases, extra-anatomical intra-plexual reconstruction - 1 case. In all cases the intra-surgical view motivated the operative intervention. The most important problem in treatment of the obstetric brachial plexus palsy is a separate group of children who need a surgical intervention.

[A case-control study on the risk factors related to obstetric brachial plexus palsy].

OBJECTIVE: To identify the risk factors and related degrees associated to obstetric brachial plexus palsy(OBPP). METHODS: A case-control study was performed. Neonatal records of thirty-one cases with OBPP and their corresponding maternal records from the Department of Gynecology and Obstetrics of eight hospitals in Shanghai city from 1988 to 2002 were reviewed. Four controls, all living in Shanghai were selected to match each case and were born within the same year at the same hospital. The control group also included 124 cases without OBPP. According to the uniformed data and tables used were from medical records and from pregnant women. Epidemiological study was carried out on both case group and control group. Variables for analyses would include: (1) race, age, height, family history, pre-pregnancy weight, body mass index at the pre-pregnancy (weight/height2) on those pregnant women as well as on parity of their mothers; (2) the process of delivery which includeing clinic pelvis evaluation, height of uterus, abdomen circumference,antepartum weight,body mass index before delivery, mode of delivery,the duration of active phase and 2nd stage of labor, shoulder dystocia; (3) on neonates: sex, gestational age, birth weight,affected limb, Apgar scores of 1 and 5 minutes, other birth trauma and resuscitation of infant. Statistical tests applied to these data would include Student's T test for continuous variables and chi2 analysis for discrete data. Risk calculation of OBPP was performed by univariable and multivariable conditional logistic regression analysis. RESULTS: 12 factors related to expsure were identified for OBPP through univariable conditional logistic regression analysis. When multivariable conditional logistic regression model at P = 0.1 was applied, four factors such as cesarean (OR = 0.060), forceps (OR = 65.237), birth weight (OR = 35.468), and pre-pregnancy body mass index (OR = 23.901) were selected. CONCLUSION: Forceps delivery,macrosomia, and increase of pre-pregnancy body mass index (> or = 21) were risk factors of OBPP in the order of degrees to risk while cesarean seemed to serve as a protective factor.

Neurological recovery in obstetric brachial plexus injuries: an historical cohort study.

An historical cohort study was conducted to investigate the rate and extent of neurological recovery in obstetric brachial plexus injury (OBPI) and to identify possible prognostic factors in a cohort of children with OBPI from birth to 7 years. All children (n=56; 31 females, 25 males) with OBPI were evaluated at fixed time intervals by one examiner. They underwent a final neurological examination at a mean age of 3 years 10 months (range 1 to 7 years). Neurological outcome was not as favourable as is often reported: complete neurological recovery occurred in 37 out of 56 children (66%). In half of these there was delayed recovery, in which case complete neurological recovery was assessed from 1.5 to 16 months of age (median age 6.5 months, SD 4.2 months). External rotation and supination were the last to recover and recovered the least. Although biceps function at three months was considered to be the best indicator for operative treatment, external rotation and supination were found to be better in predicting eventual complete recovery. Initial symptoms directly post partum were not found to be prognostic. Functional outcome was mainly reported to be good.

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.

A case of neonatal spinal cord injury: magnetic resonance imaging and somatosensory evoked potentials.

This is the first case report on the diagnosis of spinal cord injury due to hemorrhage during the neonatal period using magnetic resonance imaging (MRI). Somatosensory evoked potentials are also helpful in the functional demonstration of this lesion. When discrepant signs, alert consciousness and intact cranial nerves are observed in newborn babies with flaccid extremities and respiratory disturbance, the immediate carrying out of MRI is mandatory in order to differentiate spinal cord injury from hypoxic-ischemic encephalopathy, cerebral hemorrhage, and neuromuscular disease.

[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.

Early microsurgical reconstruction in birth palsy.

Most patients with birth palsy can be expected to recover spontaneously. But in some patients the recovery is unsatisfactory and the functional results are disappointing. One possible way to improve the prognosis for such patients is early surgical nerve reconstruction. In six infants, exploration of the brachial plexus was carried out at about six months after delivery, when there were no signs of recovery in shoulder and elbow joint movements. Preoperative metrizamide myelography, computerized tomography with intrathecal metrizamide (CT myelography), and axon reflex test (histamine test) were followed by intraoperative electrophysiologic examinations of root sensory evoked potential (SEP), nerve action potential (NAP), and evoked muscle response (M-response). Microsurgical nerve repair was performed on the basis of intraoperative diagnosis. Metrizamide myelography showed 13% false-positive root avulsion. Reliability of the histamine test was 80%. The intraoperative electro-diagnosis is essential for understanding the actual condition of the brachial plexus lesion and obtaining better results from microsurgical reconstruction in birth palsy. The surgical results, with an average follow-up evaluation of two years and four months, have been encouraging enough to continue this diagnostic and therapeutic program, though its superiority to natural recovery has not yet been clarified.

Obstetric brachial plexus palsy.

This article supplies data related to 11 operated children with obstetric brachial plexus palsy. Discussion of the obstetric background, pathology, pre- and postsurgical testing and of primary and secondary surgical reconstruction also is given. The need for rehabilitation regimen is stressed.

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.