Obstetrical brachial palsy: pathogenesis, risk factors, and prevention

Efficacy of Kinesio® tapes in obstetrical brachial plexus injury: a randomized controlled trial

OBJECTIVES

The purpose of this study was to investigate the effectiveness of Kinesio® tape application associated to exercise in patients with obstetric brachial plexus injury (OBPI).

MATERIALS AND METHODS

Ninety patients with Erb-Duchenne palsy secondary to OBPI participated in a 3-month study, in 2 groups; study group (n = 50) and control group (n = 40). Both followed the same physical therapy program, while the study group also received Kinesio® taping over the scapula and forearm. The patients were evaluated, pre- and post-treatment, using the Modified Mallet Classification (MMC), Active Movement Scale (AMS), and active range of motion (ROM) of the plegic side.

RESULTS

There were no statistically significant intergroup differences in age, gender, birth weight or plegic side (p > 0.05), or in pre-treatment MMC and AMS scores (p > 0.05). There were significant differences in favor of the study group for Mallet 2 (external rotation) (p = 0.012), Mallet 3 (hand on the back of the neck) (p < 0.001), Mallet 4 (hand on the back) (p = 0.001) and total Mallet score (p = 0.025), and for AMS shoulder flexion (p = 0.004) and elbow flexion (p < 0.001). ROM results before and after treatment (within groups) showed significant improvement in both groups (p < 0.001).

CONCLUSION

Since this a was a preliminary study, the results should be interpreted with caution in terms of clinical efficacy. The results suggest that associating Kinesio® taping to conventional treatment helps functional development in patients with OBPI.'

10-year Follow-up of Mod Quad and Triangle Tilt Surgeries in Obstetric Brachial Plexus Injury

Aim:

To evaluate whether obstetric brachial plexus injury (OBPI) children who had mod Quad and triangle tilt surgeries maintained their recovered upper extremity functional movements over 10 years.

Background:

The short-term outcomes of surgery in OBPI patients are well documented. However, only a few publications with results over 10-year postoperative follow-up exist. We have previously reported the outcomes of these 2 surgeries in OBPI after 1, 2, and 5 years. Here, we report the successful outcomes in 17 of these patients over 10 years.

Methods:

Seventeen OBPI patients, who had mod Quad, a modified muscle release operation and triangle tilt, a bony surgical procedure with us between 2005 and 2008, had postoperative follow-up of 10 years and met the inclusion criteria. Patients who had multiple surgeries and did not have 10-year follow-up are excluded in this study.

Results:

Fifteen of 17 children maintain their recovered upper extremity functions for extended long period (mean, 10 years; range, 9–13 years). There was statistically significant improvement in total functional Mallet score after 3 years (mean, 18.8 ± 2.1; P ≤ 0.01) from the preoperative mean total Mallet score of 14.5 ± 1.2. This improvement was not only maintained for extended period but also improved (mean total Mallet score, 20.35 ± 2.3; P ≤ 0.01) in some patients.

Conclusions:

Overall, all upper extremity functions improved greatly after mod Quad and triangle tilt surgeries in OBPI children, and they were able to maintain their recovered functional movements over extended period of 10 years.

Brachial plexus injury: treatment options and outcomes

The brachial plexus is a series of nerves formed by roots of cervical segments 5 to 8 (C5-C8) as well as the first thoracic nerve (T1). It functions to provide sensation and motor innervation to the skin and muscles of the chest and upper limb. It does so through different segments: roots, trunks, divisions, and cords. Injuries to the brachial plexus occur relatively frequently and are due mainly to traumatic accidents that lead to traction or compression of the nerve roots. When considering the etiology and treatment of such injuries, it is important to make a distinction between adult versus obstetric brachial plexus injury. Although several surgical treatment options are described and used for patients with brachial plexus injury, no perfect remedy currently exists. Prevention and safety should be the focus. At the same time, high-quality studies and new technology and techniques are needed to determine more effective treatments for this group.

Proximal subscapularis release for the treatment of adduction-internal rotation shoulder contracture in obstetric brachial plexus palsy

INTRODUCTION

The purpose of this paper was to evaluate the results on shoulder function following isolated proximal subscapularis release in children with Erb's palsy.

METHODS

A retrospective study was conducted on 64 consecutive children with Erb's palsy who underwent a Carlioz proximal subscapularis release between 2001 and 2012. Fifty children with complete records and a minimum follow-up of 2 years were included for evaluation. Age at surgery ranged from 1.3 to 4.5 years (average 2.6 years). Preoperative active shoulder abduction/anterior elevation, active external and internal rotations as well as the Mallet score were compared with those found at 6 and 24 months postoperatively using the Student paired t test, with a confidence interval of 95 %. The results were compared between children <3 years of age at surgery and those older, and between children who had an isolated C5-C6 and those with greater involvement. p < 0.05 was considered statistically significant.

RESULTS

Active abduction improved 21° at 6 months and 31° (total) at 2 years (p < 0.01) with an overall Mallet abduction score improvement of 0.58 at 6 months and 0.6 (overall) at 2 years (p < 0.01). Active external rotation improved 52° at 6 months and 35° (total) at 2 years (p < 0.01) with an overall Mallet external rotation score improvement of 1.3 at 6 months (p < 0.01) and 0.52 (overall) at 2 years (p = 0.013). There was no statistically significant change in internal rotation (p = 0.37). We found no correlation between the child's age or the severity of involvement at surgery and the end result.

CONCLUSION

Proximal subscapularis release according to Carlioz is simple and effective in improving overall shoulder function in children with obstetric brachial plexus palsy, mainly abduction and external rotation. Improvement tends to reach a plateau around 6-12 months postoperatively.

Obstetric brachial plexus palsy following routine versus difficult deliveries

Previous bio-engineering studies showed that intrapartum peak forces applied by the clinician were lower in routine deliveries than difficult deliveries. A total of 751 cases of obstetric brachial plexus palsy were included and divided into two groups: group I (248 patients) were born following routine deliveries and group II (503 patients) were born following difficult deliveries. Both groups were compared regarding the type of palsy and the rate of good/poor spontaneous motor recovery from the palsy. Group I subjects were more likely to have upper Erb palsy whereas those in group II were more likely to develop total palsy (P < .0001). The percentage of newborns with poor functional recovery was significantly higher (P < .05) in group II with regards to shoulder, wrist, and hand function. It was concluded that higher peak forces applied by the clinician in difficult deliveries affect the type of obstetric brachial plexus palsy.

Isolated lower brachial plexus (Klumpke) palsy with compound arm presentation: case report

Klumpke palsy has yet to be clearly documented in the newborn, because previous reports lack any description of the obstetrical history, clinical progression, or outcome. Based on a high incidence of breach presentation in the few clinical series that report Klumpke palsy, hyperabduction with arm overhead during delivery has been the presumed mechanism. We report a child with isolated lower brachial plexus palsy and Horner syndrome who presented at birth with a vertex compound arm presentation. Recognition of this condition and details of the clinical progression and outcome are important, because guidelines for management are currently not available.

Anterior release of elbow flexion contractures in children with obstetrical brachial plexus lesions

PURPOSE

A flexion contracture of the elbow is common in upper obstetric brachial plexus palsy. One less than 30° involves no major aesthetic or functional abnormalities, whereas for one greater than 30°, conservative treatment with serial splints produces variable results. We evaluated anterior release of the elbow with partial tenotomy of the anterior brachialis muscle and of the biceps, for their effect on elbow flexion contractures.

METHODS

We performed 10 anterior releases of the elbow with lengthening of the distal tendons of the biceps and the anterior brachialis muscle. All patients had upper obstetric brachial plexus palsies (C5-C6) and elbow flexion contractures of 35° or greater (range, 35° to 60°). The flexion strength of the elbow was 4 or higher on the British Medical Research Council scale, and the patients had no bone abnormalities in the elbow region.

RESULTS

After a mean follow-up period of 3 years, the mean gain in extension was 28° (range, 20° to 35°). All patients maintained flexion strength. Elbow extension was 2° less than obtained at surgery and was maintained during follow-up. All patients were satisfied or very satisfied, and none presented major complications, except hypertrophic scarring to a greater or lesser extent at the incision site.

CONCLUSIONS

Anterior release of the elbow is a useful method for treating elbow flexion contractures of more than 35° and can reduce the deformity to bring it within functional range without compromising flexion.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Perinatal brachial plexus palsy

BACKGROUND

Perinatal brachial plexus palsy (PBPP) is a flaccid paralysis of the arm at birth that affects different nerves of the brachial plexus supplied by C5 to T1 in 0.42 to 5.1 infants per 1000 live births.

OBJECTIVES

To identify antenatal factors associated with PBPP and possible preventive measures, and to review the natural history as compared with the outcome after primary or secondary surgical interventions.

METHODS

A literature search on randomized controlled trials, systematic reviews and meta-analyses on the prevention and treatment of PBPP was performed. EMBASE, Medline, CINAHL and the Cochrane Library were searched until June 2005. Key words for searches included 'brachial plexus', 'brachial plexus neuropathy', 'brachial plexus injury', 'birth injury' and 'paralysis, obstetric'.

RESULTS

There were no prospective studies on the cause or prevention of PBPP. Whereas birth trauma is said to be the most common cause, there is some evidence that PBPP may occur before delivery. Shoulder dystocia and PBPP are largely unpredictable, although associations of PBPP with shoulder dystocia, infants who are large for gestational age, maternal diabetes and instrumental delivery have been reported. The various forms of PBPP, clinical findings and diagnostic measures are described. Recent evidence suggests that the natural history of PBPP is not all favourable, and residual deficits are estimated at 20% to 30%, in contrast with the previous optimistic view of full recovery in greater than 90% of affected children. There were no randomized controlled trials on nonoperative management. There was no conclusive evidence that primary surgical exploration of the brachial plexus supercedes conservative management for improved outcome. However, results from nonrandomized studies indicated that children with severe injuries do better with surgical repair. Secondary surgical reconstructions were inferior to primary intervention, but could still improve arm function in children with serious impairments.

CONCLUSIONS

It is not possible to predict which infants are at risk for PBPP, and therefore amenable to preventive measures. Twenty-five per cent of affected infants will experience permanent impairment and injury. If recovery is incomplete by the end of the first month, referral to a multidisciplinary team is necessary. Further research into prediction, prevention and best mode of treatment needs to be done.

Spinal nerve root β-APP staining in infants is not a reliable indicator of trauma

This preliminary communication describes seven babies with β-amyloid precursor protein (βAPP) positive axonal swellings in nerve roots at multiple levels of the spinal cord. All seven babies died of natural causes. Two died in utero providing evidence for nerve root injury in the absence of trauma, two died within one day of birth and the possibility of birth related injury has to be considered. Three babies were over one month of age and had no history or pathological evidence of trauma. These findings show that if axonal injury is carefully sought in every infant death, not just in babies where trauma is suspected, it will be found in a proportion of babies dying from natural diseases. While spinal nerve root axonal injury in infants may suggest trauma, it is not, in itself, diagnostic of trauma.

Shoulder Dystocia: Etiology, Common Risk Factors, and Management

Shoulder dystocia and brachial plexus injury occur in 0.5% to 1.5% of all births. Risk factors for both include maternal obesity, excessive prenatal weight gain, maternal diabetes, protracted labor, and fetal macrosomia. These factors are involved in only about 50% of births complicated by shoulder dystocia or brachial plexus injury. Shoulder dystocia has a low recurrence rate (9.8%-16.7%), although history of previous shoulder dystocia is the most reliable predictor of occurrence. Brachial plexus injury is the most common morbidity associated with shoulder dystocia, but 50% of newborns who present with this injury were not subject to shoulder dystocia at birth. Most brachial plexus injuries are transient, although 5% to 22% become permanent. Shoulder dystocia followed by permanent brachial plexus injury or mental impairment is one of the leading causes of malpractice allegations. Prompt assessment and management of shoulder dystocia and preparation to maximize the efficiency of shoulder dystocia maneuvers are critical. Documentation of the appropriate use of maneuvers to relieve shoulder dystocia demonstrates standard of care practice, thereby decreasing the potential for successful malpractice allegations.

An unusual case of Erb's palsy in a neonate: a case report

Erb's palsy occurs in neonates following traumatic delivery, where excessive traction on the neck stretches these nerve roots. Nonobstetric causes of Erb's palsy are rare in neonates. The authors report the presentation of a female neonate with Erb's palsy following a postero-lateral thoracotomy. The infant underwent surgery on day 3 of life for esophageal atresia and presented with right upper limb weakness on day 21 of life. She demonstrated features of Erb's palsy with normal higher mental functions. An electromyography and nerve conduction study confirmed Erb's palsy. The surgical procedure in the index case did not involve the brachial plexus. However, her right upper limb was positioned hyperabducted during the intraoperative period, which possibly had led to the palsy. The key message of this report is that prolonged stretching of the brachial plexus roots during surgery of the neck and thorax can be an important nonobstetric cause of Erb's palsy in neonates.

Shoulder function and anatomy in complete obstetric brachial plexus palsy: long-term improvement after triangle tilt surgery

PURPOSE

Untreated complete obstetric brachial plexus injury (COBPI) usually results in limited spontaneous recovery of shoulder function. Older methods used to treat COBPI have had questionable success, with very few studies being published. The purpose of the current study was to examine the results of triangle tilt surgery on shoulder function and development in COBPI individuals.

METHODS

This study was conducted as a retrospective chart review. Inclusion criteria were COBPI patients that had undergone the triangle tilt procedure from 2005 to 2009 and were between the ages of 9 months and 12 years. COBPI was defined as permanent injury to all five nerve roots (C5-T1), with significant degradation in development and function of the hand. Twenty-five patients with a mean age of 5 (0.75-12) years were followed up clinically for more than 2 years.

RESULTS

The triangle tilt procedure resulted in demonstrable clinical enhancements with appreciable improvements in shoulder function, glenoid version, and humeral head congruity. There was a significant increase in the overall Mallet score (2.4 points, p < 0.0001) following surgical correction in patients that were followed up for more than 2 years.

CONCLUSIONS

The results of this study demonstrate that COBPI patients who develop SHEAR and medial rotation contracture deformities can benefit from the triangle tilt surgery, which improves shoulder function and anatomy across a range of pediatric ages. Despite these patients presenting late for surgery in general (5 years), significant improvements were observed in their glenohumeral (GH) dysplasia and their ability to perform shoulder and arm movements following surgery.

Shoulder dystocia related fetal neurological injuries: the role of diabetic control

The study explores the roles of routine prenatal diabetic screening and control in the occurrence of neurological birth injuries associated with shoulder dystocia. The investigation involved retrospective review of 226 medical records that contained information about the antenatal events in cases that resulted in permanent neonatal injuries following arrest of the shoulders at delivery. Close attention was paid to diabetic screening and management of mothers with evidence of glucose intolerance. Analysis of the records revealed that one-third of all women, including those with predisposing factors, received no diabetic screening during pregnancy. The majority of confirmed diabetic patients were not treated adequately. Among babies of diabetic women, birth weights exceeding 4500 g were about 30-fold more frequent than among those with normal glucose tolerance. The data suggest that universal screening and rigid diabetic control, including mothers with borderline glucose tolerance, are effective measures for the prevention of excessive fetal growth and intrapartum complications deriving from it. If ignored, impaired maternal glucose tolerance may become a major predisposing factor for neurological birth injuries. It appears therefore that with routine screening for diabetic predisposition and effective control of gestational diabetes the risk of fetal damage can be reduced substantially.

Combined intrauterine vascular insufficiency and brachial plexus palsy: A case report

A unique case of combined intrauterine vascular insufficiency and complete brachial plexus palsy is described in a newborn delivered by cesarean section. Intrauterine vascular insufficiency resulted in a right below elbow amputation at 3 weeks of age. Amputation length was preserved after a pedicled thoracoabdominal flap. Function of the C5, C6, and C7 nerve roots returned to normal by 3 months of age.

Obstetrical brachial plexus palsy

Obstetrical brachial plexus palsy, one of the most complex peripheral nerve injuries, presents as an injury during the neonatal period. The majority of the children recover with either no deficit or a minor functional deficit, but it is almost certain that some will not regain adequate limb function. These few cases must be managed in an optimal way. Considerable medical and legal debate has surrounded the etiologic factors of this traumatic lesion, and obstetricians are often considered responsible for the injury. According to recent studies, spontaneous endogenous forces may contribute substantially to this type of neonatal trauma. All obstetric circumstances that predispose to brachial plexus damage and that could be anticipated should be assessed. Correct diagnosis is necessary for the accurate estimation of prognosis and treatment. The most important aspect of therapy is timely recognition and referral, to prevent the various possible sequelae affecting the shoulder, elbow, or forearm. Since the early 1990s, research has increased the understanding of obstetrical brachial plexus palsy. Further research is needed, focused on developing strategies to predict brachial injury. This review focuses on emerging data relating to obstetrical brachial plexus palsy and discusses the present controversies regarding natural history, prognosis, and treatment in infants with brachial plexus birth palsies.

Shoulder dystocia: nursing prevention and posttrauma care

Shoulder dystocia is a birth emergency that occurs in approximately 1% of all births. Shoulder dystocia can be followed by broken clavicle or humerus, brachial plexus injury, fetal hypoxia, or death. Although risk factors for shoulder dystocia include previous birth complicated by shoulder dystocia, maternal obesity, excessive prenatal weight gain, fetal macrosomia, gestational diabetes, and instrumental delivery, shoulder dystocia is not predictable. Perinatal nurses can reduce the risk for shoulder dystocia by teaching mothers about optimal weight gain in pregnancy and assisting mothers with diabetes to prevent hyperglycemia through diet management and medication use. During childbirth preparation or early labor, nurses can educate mothers about position changes and maneuvers used for shoulder dystocia. Nurses play a vital role in obtaining assistance during a shoulder dystocia, keeping time, assisting with maneuvers such as suprapubic pressure, and documenting the dystocia management. Nurses can assist mothers and families to review the shoulder dystocia and any newborn injuries in the postpartum period, thereby reducing confusion and anxiety. Regular drills and case reviews help build nursing shoulder dystocia management skills.

Shoulder dystocia related fetal neurological injuries: the predisposing roles of forceps and ventouse extractions

On the basis of 333 documented cases of permanent perinatal neurological damage, associated with arrest of the shoulders at birth, the authors conducted a retrospective study in order to evaluate the predisposing role, if any, of the utilization of extraction instruments. The investigation revealed that 35% of all injuries occurred in neonates delivered by forceps, ventouse or sequential ventouse-forceps procedures. This frequency was several-fold higher than the prevailing instrument use in the practices of American obstetricians during the same years. A high rate of forceps and ventouse extractions was demonstrable in all birth weight categories. Average weight and moderately large for gestational age fetuses underwent instrumental extractions more often than grossly macrosomic ones. This circumstance indicates that forceps and ventouse are independent risk factors, unrelated to fetal size. Their use entailed central nervous system injuries significantly more often than did spontaneous deliveries. The findings suggest that extraction procedures may be as important as macrosomia among the factors that lead to neurological damage in the child in connection with shoulder dystocia. Because they augment the intrinsic dangers of excessive fetal size exponentially, the authors consider their use in case of > or =4,000 g estimated fetal weight inadvisable. Sequential forceps-ventouse utilization further doubles the risks and is, therefore, to be avoided in all circumstances.

The contralateral unimpaired arm as a control for upper extremity kinematic analysis in children with brachial plexus birth palsy

BACKGROUND

Kinematic studies of abnormal upper extremity (UE) motion provide the unique and valuable perspective of motion analysis during simulated functional tasks. However, they require comparison with healthy control data. Obtaining this control data usually entails testing a healthy population, which can be costly and time consuming, requiring separate subject inclusion criteria, recruitment, and institutional review board approval. The kinematics of the unimpaired UE in people with unilateral impairment have not been analyzed and documented. The purpose of this study was to compare UE motion during activities of daily living in the contralateral unimpaired arm of subjects with brachial plexus birth palsy (BPBP) with an age-matched control population.

METHODS

The contralateral arms of 40 subjects with unilateral BPBP were compared with the arms of 15 healthy subjects using an established 3-dimensional upper extremity motion analysis protocol.

RESULTS

There were no significant differences between the 2 arms on 17 of 19 motion parameters. The 2 differences that were statistically significant (P < 0.05) were not clinically meaningful.

CONCLUSIONS

The contralateral arms of children with unilateral BPBP can be used as controls for future upper extremity motion analysis studies of this population, and further recruitment of age-matched controls is not necessary for comparison with 5- to 8-year-old children with BPBP.

Part 2. Distinguishing physical characteristics and management of brachial plexus injuries

Brachial plexus injuries (BPI) are usually readily apparent at or shortly after birth. Failure of caregivers to recognize and appropriately treat BPI may contribute to the risk of life-long neuromuscular dysfunction for the infant and represents a serious medical-legal liability for the delivery provider. This article is the second in a series on BPI and provides a standard classification and a systematic guide to physical examination of the infant with suspected BPI. Conditions that mimic BPI are discussed along with diagnostic studies used to confirm this disorder. The natural history and predictors of outcome are presented along with a sample treatment protocol. Pictures and video clips are provided to enhance the reader's understanding of the consequences of this injury and the potential for improvement with surgical treatment. Useful Internet resources for parents, focused discharge planning, and guidelines for appropriate monitoring and follow-up are provided. Advantages of early referral and management by a multidisciplinary team at a brachial plexus specialty center are discussed.

High birthweight and shoulder dystocia: the strongest risk factors for obstetrical brachial plexus palsy in a Swedish population-based study

BACKGROUND

Obstetrical brachial plexus palsy (OBPP) is a serious form of neonatal morbidity.

OBJECTIVE

The aim of this work was to study the incidence of OBPP and to analyze its risk factors.

METHODS

This is a population-based retrospective case-control study. All deliveries recorded in the Swedish Medical Birth Registry between 1987 and 1997 (n = 1 213 987) were investigated. Cases (n = 2399) with OBPP were compared to all other cases.

RESULTS

The incidence of OBPP increased from 0.17 in 1987 to 0.27% in 1997 (p = 0.002). During the same time period, the mean birthweight increased from 3483 to 3525 g. Birthweight increasing from 4000 g was associated with a progressive rise in OBPP risk. Other significant risk factors associated with the injury were shoulder dystocia, breech presentation in vaginal delivery, operative vaginal delivery, diabetes mellitus, induction of labor, protracted active phase, secondary arrest of dilatation, and epidural anesthesia. Cesarean section was associated with a decreased risk of OBPP. If 5000 g is chosen as cut-off for cesarean section, 85% of the infants in this weight class are underestimated using ultrasonography. Approximately, 331 abdominal deliveries have to be performed to avoid one case of OBPP.

CONCLUSIONS

Shoulder dystocia and infant birthweight of 4500 g and more are the strongest risk factors for OBPP in a Swedish population.

Part 1. Injuries to the brachial plexus: mechanisms of injury and identification of risk factors

Upper-arm weakness (paresis) or paralysis indicates peripheral-nerve damage to the brachial plexus, a network of lower cervical and upper thoracic spinal nerves supplying the arm, forearm, and hand. Physical findings reflect muscle paralysis from spinal nerve roots. The mechanism of injury includes maternal, obstetric, and infant factors that apply traction on or compression to the anatomically vulnerable brachial plexus. Nerve regeneration can occur if nerve tissue components are preserved. Recovery is affected by multiple factors, including the type and site of injury, intervention timing, and developmental factors. The majority of injuries recover in days or months; however, residual deficits can persist. Part 1 of 2 of this article provides an overview of the neurophysiology of peripheral-nerve damage and nerve regeneration. The multifactorial etiology of brachial plexus injuries will be reviewed. Photographs and on-line video clips will enhance the description of the brachial plexus injury classifications and illustrate mechanisms of shoulder dystocia and obstetric relief maneuvers. A systematic approach to the physical examination will be explored in Part 2. Serial evaluation of motor function recovery is essential and is accomplished by appropriate referrals and follow-up. Part 2 will also describe treatment options and discuss anticipatory parent guidance.

Local administration of glial cell line-derived neurotrophic factor improves behavioral and histological deficit of neonatal Erb's palsy in rats

OBJECTIVE

We sought to evaluate from a behavioral and histological viewpoint the effect of local administration of glial cell line-derived neurotrophic factor (GDNF) on neonatal preganglionic Erb's palsy in rats.

METHODS

The Erb's palsy model was produced by transecting the anterior and posterior roots of the left C5-C7 nerves of 7-day-old rats. The rats were divided into GDNF-treated (n = 10) and vehicle-treated groups (n = 11). After we transected the roots, contact in the proximal and distal stumps of the transected nerves was maintained, and the transected point and the entire intraspinal portion of the transected roots were enclosed by Gelfoam soaked with 10 micro g GDNF or saline. The behavioral evaluation consisted of a foot-fault test and a forepaw muscle strength test, all of which were performed from the third to the seventh weeks after the operation. Seven weeks after the operation, all rats were killed, the number of anterior horn cells was counted at C5-C7, and the differences on each side were compared.

RESULTS

In the vehicle-treated group, the foot-fault test indicated an abnormality in forelimb function on the root transection side. In the GDNF-treated group, however, significant improvement in forelimb function was observed on the basis of the foot-fault test results obtained in the third to sixth weeks after the operation. In the histological evaluation, the number of anterior horn cells from the side in which the operation took place in the vehicle-treated group was significantly less than that taken from the contralateral side at each segment. In the GDNF-treated group, however, there was no difference in any of the segments, regardless of the side from which they were taken.

CONCLUSION

Local administration of GDNF in a neonatal preganglionic Erb's palsy model resulted in significant improvement in deficits on the basis of behavioral and histological evaluations.

Obstetrical brachial plexus palsy

Since the days of Hippocrates, scripts have included descriptions of infants who were unable to move their arms. However, it was not until the mid-1700s that an obstetric cause for the paralysis was considered. In 1872, the term obstetrical brachial plexus palsy was coined when a correlation was made between excessive traction on the brachial plexus during delivery and the clinical finding of arm paralysis. Surgical intervention became the norm in the beginning of the 19th century and continued until 1930. Poor outcomes and spontaneous resolution of obstetrical brachial plexus palsy prompted a 40-year span of conservative treatment. By the late 1960s, advances in technology and microsurgical techniques revived interest in surgical intervention in the management of obstetrical brachial plexus palsy. This article focuses on obstetrically caused brachial plexus injury, including risk factors, clinical presentation, and treatment options and outcomes. An understanding of current medical practices and their outcomes also provides a basis on which to develop sound support strategies to help parents who face this dilemma.