Spontaneous vaginal delivery: a risk factor for Erb's palsy?

Universal late pregnancy ultrasound screening to predict adverse outcomes in nulliparous women: a systematic review and cost-effectiveness analysis

BACKGROUND

Currently, pregnant women are screened using ultrasound to perform gestational aging, typically at around 12 weeks' gestation, and around the middle of pregnancy. Ultrasound scans thereafter are performed for clinical indications only.

OBJECTIVES

We sought to assess the case for offering universal late pregnancy ultrasound to all nulliparous women in the UK. The main questions addressed were the diagnostic effectiveness of universal late pregnancy ultrasound to predict adverse outcomes and the cost-effectiveness of either implementing universal ultrasound or conducting further research in this area.

DESIGN

We performed diagnostic test accuracy reviews of five ultrasonic measurements in late pregnancy. We conducted cost-effectiveness and value-of-information analyses of screening for fetal presentation, screening for small for gestational age fetuses and screening for large for gestational age fetuses. Finally, we conducted a survey and a focus group to determine the willingness of women to participate in a future randomised controlled trial.

DATA SOURCES

We searched MEDLINE, EMBASE and the Cochrane Library from inception to June 2019.

REVIEW METHODS

The protocol for the review was designed a priori and registered. Eligible studies were identified using keywords, with no restrictions for language or location. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. Health economic modelling employed a decision tree analysed via Monte Carlo simulation. Health outcomes were from the fetal perspective and presented as quality-adjusted life-years. Costs were from the perspective of the public sector, defined as NHS England, and the costs of special educational needs. All costs and quality-adjusted life-years were discounted by 3.5% per annum and the reference case time horizon was 20 years.

RESULTS

Umbilical artery Doppler flow velocimetry, cerebroplacental ratio, severe oligohydramnios and borderline oligohydramnios were all either non-predictive or weakly predictive of the risk of neonatal morbidity (summary positive likelihood ratios between 1 and 2) and were all weakly predictive of the risk of delivering a small for gestational age infant (summary positive likelihood ratios between 2 and 4). Suspicion of fetal macrosomia is strongly predictive of the risk of delivering a large infant, but it is only weakly, albeit statistically significantly, predictive of the risk of shoulder dystocia. Very few studies blinded the result of the ultrasound scan and most studies were rated as being at a high risk of bias as a result of treatment paradox, ascertainment bias or iatrogenic harm. Health economic analysis indicated that universal ultrasound for fetal presentation only may be both clinically and economically justified on the basis of existing evidence. Universal ultrasound including fetal biometry was of borderline cost-effectiveness and was sensitive to assumptions. Value-of-information analysis indicated that the parameter that had the largest impact on decision uncertainty was the net difference in cost between an induced delivery and expectant management.

LIMITATIONS

The primary literature on the diagnostic effectiveness of ultrasound in late pregnancy is weak. Value-of-information analysis may have underestimated the uncertainty in the literature as it was focused on the internal validity of parameters, which is quantified, whereas the greatest uncertainty may be in the external validity to the research question, which is unquantified.

CONCLUSIONS

Universal screening for presentation at term may be justified on the basis of current knowledge. The current literature does not support universal ultrasonic screening for fetal growth disorders.

FUTURE WORK

We describe proof-of-principle randomised controlled trials that could better inform the case for screening using ultrasound in late pregnancy.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42017064093.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 15. See the NIHR Journals Library website for further project information.

Brachial Plexus Birth Injury in Elective Versus Emergent Caesarean Section: A Cohort Study

OBJECTIVE

Although Caesarean section (CS) is protective for brachial plexus birth injury (BPBI), the incidence is not zero. A trial of labour with unfavourable intrauterine positioning is hypothesized to result in excessive force on the brachial plexus. The purpose of this study was to determine the risk of BPBI in emergent CS versus elective CS.

METHODS

This was a retrospective cohort study. The authors used a nationwide demographic sample of all infants born in Canada from 2004 to 2012. BPBI diagnoses, risk factors, and national incidence data were obtained from the Canadian Institute for Health Information Discharge Abstract Database and Hospital Morbidity Database. The primary outcome was risk of BPBI in emergent CS versus elective CS.

RESULTS

BPBI incidence was 1.24 per 1000 live births. Known biases may have underestimated the incidence. CS (elective and emergent) was protective for BPBI as compared with vaginal delivery (odds ratio [OR] 0.15; 95% confidence interval [CI] 0.13-0.18, P < 0.0001). Emergent CS was a moderately strong risk factor for BPBI versus elective CS (OR 3.14; 95% CI 1.79-5.10, P = 0.0001).

CONCLUSION

Emergent CS is a moderate risk factor for BPBI compared with elective CS. Intrauterine positioning with a trial of labour may provide an antenatal etiology in these distinct cases.

Birthweight thresholds for increased risk for maternal and neonatal morbidity following vaginal delivery: a retrospective study

PURPOSE

To determine neonatal birthweight (BW) thresholds for adverse maternal and neonatal outcome following vaginal delivery.

METHODS

A retrospective cohort study of all women with singleton pregnancies who underwent vaginal delivery in a university-affiliated tertiary hospital (1996-2015). The association between BW and adverse outcome in neonates with BW ≥ 3500 g (> 90th centile BW at 37 weeks' gestation) with 100 g-increment groups was explored. Pregnancies complicated by diabetes mellitus, fetal anomalies or cesarean deliveries were excluded. The composite neonatal outcome was defined as shoulder dystocia or brachial plexus injury. The composite maternal outcome was defined as postpartum hemorrhage or third- or fourth-degree perineal tears.

RESULTS

Of the 121,728 deliveries during the study period, 26,920 (22.1%) met inclusion criteria. Of these, 1024 (3.8%) had a composite adverse maternal outcome and 947 (3.5%) had a composite adverse neonatal outcome. The rates of composite maternal outcomes increased significantly only at a BW of 4800 g and above. The composite neonatal outcomes increased significantly only at a BW of 4400 g and above. In multivariate analysis, after subcategorizing our cohort into 3 BW groups [3500-3999 g (control, n = 23,030); 4000-4399 g (n = 3494); ≥ 4400 g (n = 396)], BW was associated with adverse neonatal outcomes in a dose-dependent manner. In the BW ≥ 4400 g group, to prevent one case of shoulder dystocia or Erb's palsy, 12 cesarean deliveries needed to be performed.

CONCLUSION

For non-diabetic mothers who deliver vaginally, neonatal BW ≥ 4400 g was associated with a significant increase in adverse neonatal outcomes, whereas neonatal BW ≥ 4800 g was associated with a significant increase in adverse maternal outcomes.

A multistate population-based analysis of linked maternal and neonatal discharge records to identify risk factors for neonatal brachial plexus injury

OBJECTIVE

To evaluate the interaction and contribution of maternal and fetal risk factors associated with neonatal brachial plexus injury (BPI).

METHODS

In a case-control study, matched maternal and neonatal discharge records were accessed from US State Inpatient Databases for New Jersey (2010-2012), Michigan (2010-2011), and Hawaii (2010-2011). Univariate and multivariate logistic regressions were used to evaluate associations between risk factors and BPI. Area under the receiver operating characteristic curve was used to build predictive models, including two stratified models evaluating deliveries among obese and diabetic cohorts.

RESULTS

Among 376 325 deliveries, BPI was diagnosed in 274 (0.1%). Significant BPI risk factors included maternal obesity (odds ratio [OR] 2.7, 95% confidence interval [CI] 1.7-4.4), maternal diabetes (OR 4.6, 95% CI 3.0-7.0), use of forceps (OR 4.6, 95% CI 2.3-9.0), and vacuum assistance (OR 2.3, 95% CI 1.7-3.3). After adjusting for shoulder dystocia and other predictive factors, cesarean reduced the risk of BPI by 88% (OR 0.1, 95% CI 0.07-0.2). When stratified by obesity and diabetes, the ORs for BPI increased significantly for macrosomia, forceps, and vacuum assistance.

CONCLUSION

The analysis confirms and quantifies more precisely the impact of risk factors for neonatal BPI, and provides a reliable basis for evidence-based clinical decision-making models.

Obstetrical brachial plexus injury: burden in a publicly funded, universal healthcare system

OBJECT The aim of this study was to determine the volume and timing of referrals for obstetrical brachial plexus injury (OBPI) to multidisciplinary centers in a national demographic sample. Secondarily, we aimed to measure the incidence and risk factors for OBPI in the sample. The burden of OBPI has not been investigated in a publicly funded system, and the timing and volume of referrals to multidisciplinary centers are unknown. The incidence and risk factors for OBPI have not been established in Canada. METHODS This is a retrospective cohort study. The authors used a demographic sample of all infants born in Canada, capturing all children born in a publicly funded, universal healthcare system. OBPI diagnoses and corresponding risk factors from 2004 to 2012 were identified and correlated with referrals to Canada's 10 multidisciplinary OBPI centers. Quality indicators were approved by the Canadian OBPI Working Group's guideline consensus group. The primary outcome was the timing of initial assessment at a multidisciplinary center, "good" if assessed by the time the patient was 1 month of age, "satisfactory" if by 3 months of age, and "poor" if thereafter. Joinpoint regression analysis was used to determine the OBPI incidence over the study period. Odds ratios were calculated to determine the strength of association for risk factors. RESULTS OBPI incidence was 1.24 per 1000 live births, and was consistent from 2004 to 2012. Potential biases underestimate the level of injury identification. The factors associated with a very strong risk for OBPI were humerus fracture, shoulder dystocia, and clavicle fracture. The majority (55%-60%) of OBPI patients identified at birth were not referred. Among those who were referred, the timing of assessment was "good" in 28%, "satisfactory" in 66%, and "poor" in 34%. CONCLUSIONS Shoulder dystocia was the strongest modifiable risk factor for OBPI. Most children with OBPI were not referred to multidisciplinary care. Of those who were referred, 72% were assessed later than the target quality indicator of 1 month that was established by the national guideline consensus group. A referral gap has been identified using quality indicators at clinically relevant time points; this gap should be addressed with the use of knowledge tools (e.g., a clinical practice guideline) to target variations in referral rates and clinical practice. Interventions should guide the referral process.

Traumatic peripheral neuropraxias in neonates: a case series

Traumatic peripheral nerve palsies in the newborn are uncommon but are a cause of severe anxiety in parents. Erb's palsy, brachial plexus, radial nerve and facial nerve are the common nerves affected. Perinatal injuries are the most frequent cause of traumatic peripheral neuropraxias / nerve palsies. Usually these neuropraxias are self-limited with good recovery with conservative management in majority of cases.Ten neonates with peripheral neuropraxias were included in this retrospective study based on a review of these cases over a period of three and a half years. Their clinical profile, presenting symptoms, predisposing factors and management were analyzed. We encountered five neonates with erb's palsy, three with facial palsy and two had radial nerve affection. Risk factors in our series included large babies, prolonged or difficult labour, instrumental delivery and shoulder dystocia. All cases of peripheral nerve involvement were managed conservatively with physiotherapy. Nine neonates were discharged and showed gradual improvement and one patient unfortunately succumbed due to severe birth asphyxia. Parental counseling and rehabilitation play an important part in management of these cases.

Neonatal injury at cephalic vaginal delivery: a retrospective analysis of extent of association with shoulder dystocia

Purpose

To describe the risk factors and labor characteristics of Clavicular fracture (CF) and brachial plexus injury (BPI); and compare antenatal and labor characteristics and prognosis of obstetrical BPI associated with shoulder dystocia with obstetrical BPI not associated with shoulder dystocia.

Methods

This retrospective study consisted of women who gave birth to an infant with a fractured clavicle or BPI between January 2009 and June 2013. Antenatal and neonatal data were compared between groups. The control group (1300) was composed of the four singleton vaginal deliveries that immediately followed each birth injury. A multivariable logistic regression model, with backward elimination, was constructed in order to find independent risk factors associated with BPI and CF. A subgroup analysis involved comparison of features of BPI cases with or without associated shoulder dystocia.

Results

During the study period, the total number of vaginal deliveries was 44092. The rates of CF, BPI and shoulder dystocia during the study period were 0,6%, 0,16% and 0,29%, respectively. In the logistic regression model, shoulder dystocia, GDM, multiparity, gestational age >42 weeks, protracted labor, short second stage of labor and fetal birth weight greater than 4250 grams increased the risk of CF independently. Shoulder dystocia and protracted labor were independently associated with BPI when controlled for other factors. Among neonates with BPI whose injury was not associated with shoulder dystocia, five (12.2%) sustained permanent injury, whereas one neonate (4.5%) with BPI following shoulder dystocia sustained permanent injury (p = 0.34).

Conclusion

BPI not associated with shoulder dystocia might have a higher rate of concomitant CF and permanent sequelae.

Risk factors for neonatal brachial plexus palsy

Neonatal brachial plexus palsy (NBPP) is an unpredictable complication of childbirth. Historic risk factors for the occurrence of NBPP have included shoulder dystocia, fetal macrosomia, labor abnormalities, operative vaginal delivery, and prior NBPP. However, whether studied alone or in combination, these risk factors have not been shown to be reliable predictors. The majority of NBPP cases occur in women with infants <4500 g who are not diabetic and have no other identifiable risk factors. Furthermore, cesarean section reduces but does not completely eliminate the risk for NBPP. In this section, the relationship of these historic obstetric risk factors to the occurrence of NBPP is further explored.

Neonatal brachial plexus palsy: incidence, prevalence, and temporal trends

Epidemiological knowledge of the incidence, prevalence, and temporal changes of neonatal brachial plexuses palsy (NBPP) should assist the clinician, avert unnecessary interventions, and help formulate evidence-based health policies. A summary of 63 publications in the English language with over 17 million births and 24,000 NBPPs is notable for six things. First, the rate of NBPP in the US and other countries is comparable: 1.5 vs. 1.3 per 1000 total births, respectively. Second, the rate of NBPP may be decreasing: 0.9, 1.0 and 0.5 per 1,000 births for publications before 1990, 1990-2000, and after 2000, respectively. Third, the likelihood of not having concomitant shoulder dystocia with NBPP was 76% overall, though it varied by whether the publication was from the US (78%) vs. other countries (47%). Fourth, the likelihood of NBPP being permanent (lasting at least 12 months) was 10-18% in the US-based reports and 19-23% in other countries. Fifth, in studies from the US, the rate of permanent NBPP is 1.1-2.2 per 10,000 births and 2.9-3.7 per 10,000 births in other nations. Sixth, we estimate that approximately 5000 NBPPs occur every year in the US, of which over 580-1050 are permanent, and that since birth, 63,000 adults have been afflicted with persistent paresis of their brachial plexus. The exceedingly infrequent nature of permanent NBPP necessitates a multi-center study to improve our understanding of the antecedent factors and to abate the long-term sequela.

[Management of pregnancies with a previous cesarean]

The cesarean rate in France has reached 21% in 2010. With a maintained fertility rate, management of a pregnant woman with a previous caesarean scar is becoming a daily situation for most obstetrical teams. Considering the small rate of vaginal birth after cesarean (VBAC), we will try to establish an up-to-date review of the benefits and risks of encouraging trial of VBAC. This information can help professionals provide adequate counselling women or couples.

[Prediction, prevention and management of shoulder dystocia]

Shoulder dystocia is one of the most tragic, fatal and unexpected obstetrical events, which is mostly unpredictable and unpreventable. This clinical picture is defined as a delivery that requires additional obstetric maneuvers to release the shoulders after gentle downward traction has failed. Shoulder dystocia occurs when the fetal shoulder impacts on the maternal symphysis or sacral promontory. The incidence of shoulder dystocia is 0.2-0.6%. High perinatal mortality and morbidity is associated with the condition, even when it is managed appropriately. Obstetricians should be aware of the existing risk factors, but should always be alert to the possibility of shoulder dystocia in all labors. Maternal morbidity is also increased, particularly postpartum hemorrhage, rupture of the uterus, injury of the bladder, urethra and the bowels and fourth-degree perineal tears. Complications of the newborn include asphyxia, perinatal mortality, fracture of the clavicula and the humerus. Brachial plexus injuries are one of the most important fetal complications of shoulder dystocia, complicating 4-16% of such deliveries. The purpose of this article is to review the current evidence regarding the possible prediction, prevention and management of shoulder dystocia.

Risk factors at birth for permanent obstetric brachial plexus injury and associated osseous deformities

Purpose. To examine the most prevalent risk factors found in patients with permanent obstetric brachial plexus injury (OBPI) to identify better predictors of injury. Methods. A population-based study was performed on 241 OBPI patients who underwent surgical treatment at the Texas Nerve and Paralysis Institute. Results. Shoulder dystocia (97%) was the most prevalent risk factor. We found that 80% of the patients in this study were not macrosomic, and 43% weighed less than 4000 g at birth. The rate of instrument use was 41% , which is 4-fold higher than the 10% predicted for all vaginal deliveries in the United States. Posterior subluxation and glenoid version measurements in children with no finger movement at birth indicated a less severe shoulder deformity in comparison with those with finger movement. Conclusions. The average birth weight in this study was indistinguishable from the average birth weight reported for all brachial plexus injuries. Higher birth weight does not, therefore, affect the prognosis of brachial plexus injury. We found forceps/vacuum delivery to be an independent risk factor for OBPI, regardless of birth weight. Permanently injured patients with finger movement at birth develop more severe bony deformities of the shoulder than patients without finger movement.

Reducing the risk of shoulder dystocia and associated brachial plexus injury

Despite persisting controversy over shoulder dystocia prediction, prevention, and injury causation, the authors find considerable evidence in recent research in the field to recommend additional guidelines beyond the current American College of Obstetricians and Gynecologists and Royal College of Obstetricians and Gynecologists guidelines to improve clinical practice in managing patients at risk for experiencing shoulder dystocia. In this article, the authors offer health care providers information, practical direction, and advice on how to limit shoulder dystocia risk and, more importantly, to reduce adverse outcome risk.

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.

Screening for gestational diabetes mellitus: cost-utility of different screening strategies based on a woman's individual risk of disease

AIMS/HYPOTHESIS

The cost-effectiveness of eight strategies for screening for gestational diabetes (including no screening) was estimated with respect to the level of individual patient risk.

METHODS

Cost-utility analysis using a decision analytic model populated with efficacy evidence pooled from recent randomised controlled trials, from the funding perspective of the National Health Service in England and Wales. Seven screening strategies using various combinations of screening and diagnostic tests were tested in addition to no screening. The primary outcome measure was the incremental cost per quality-adjusted life-year (QALY) over a lifetime.

RESULTS

The strategy that has the greatest likelihood of being cost-effective is dependent on the risk of gestational diabetes mellitus for each individual woman. When gestational diabetes mellitus risk is <1% then the no screening/treatment strategy is cost-effective; where risk is between 1.0% and 4.2% fasting plasma glucose followed by OGTT is most likely to be cost-effective; and where risk is >4.2%, universal OGTT is most likely to be cost-effective. However, acceptability of the test alters the most cost-effective strategy.

CONCLUSIONS/INTERPRETATION

Screening for gestational diabetes can be cost-effective. The best strategy is dependent on the underlying risk of each individual and the acceptability of the tests used. The current study suggests that if a woman's individual risk of gestational diabetes could be accurately predicted, then healthcare resource allocation could be improved by providing an individualised screening strategy.

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.

Is it possible to reduce obstetrical brachial plexus palsy by optimal management of shoulder dystocia?

Obstetrical brachial plexus palsies (OBPP) have been historically attributed to the impaction of the fetal shoulder behind the symphysis pubis and to excessive lateral traction of the fetal head during maneuvers to deliver the fetal shoulders in shoulder dystocia. Shoulder dystocia is indeed a major risk factor as it increases the risk for OBPP 100-fold. The incidence of OBPP following shoulder dystocia varies widely from 4% to 40%. However, a significant proportion of OBPPs are secondary to in utero injury. The propulsive forces of labor, intrauterine maladaptation, and compression of the posterior shoulder against the sacral promontory as well as uterine anomalies are possible intrauterine causes of OBPP. Many risk factors for OBPP may be unpredictable. Early identification of risk factors for shoulder dystocia, as well as appropriate management when it occurs, may improve our ability to prevent the occurrence of OBPP in those cases that are caused by shoulder dystocia.

Delivery after previous cesarean: long-term outcomes in the child

In subsequent pregnancies after a cesarean delivery, women must choose between attempting to deliver vaginally or undergoing another cesarean delivery. Information relevant to this choice includes the long-term benefits and harms to the baby. In this article we discuss the relationship of mode of delivery (planned trial of labor, either with or without vaginal delivery, or elective repeat cesarean delivery) and long-term outcomes, including brachial plexus palsy, neurodevelopmental impairment, and asthma. No randomized trials are available that relate directly to the choice of delivery method after previous cesarean. Observational studies suggest that cesarean delivery might be associated with a greater risk of asthma, caused perhaps by altered gut colonization, increased risk of neonatal respiratory disease, decreased gestational age at birth or decreased likelihood of breastfeeding. By contrast, vaginal delivery after a previous cesarean delivery is associated with greater risks of neurodevelopmental impairment and upper-extremity motor impairment, caused, respectively, by greater risks of perinatal hypoxic-ischemic encephalopathy and brachial plexus injury. Available information does not provide a precise estimate of the relative risks for infants delivered after a trial of labor versus elective cesarean delivery.

Permanent brachial plexus birth palsy does not impair the development and function of the spine and lower limbs

Permanent brachial plexus birth palsy (BPBP) impairs the function of the affected upper limb. Avulsion type root injuries may damage the cervical spinal cord. Whether abnormal function of an upper limb affected by BPBP has any observable effects on the development of the locomotion system and overall motor function has not been clarified in depth. A total of 111 patients who had undergone brachial plexus surgery for BPBP in infancy were examined after a mean follow-up time of 13 (5-32) years. Patients' physical activities were recorded by a questionnaire. No significant inequalities in leg length were found and the incidence of structural scoliosis (1.7%) did not differ from that of the reference population. Nearly half of the patients (43%) had asynchronous motion of the upper limbs during gait, which was associated with impaired upper limb function. Data obtained from the completed questionnaires indicated that only few patients were unable to participate in normal activities such as: bicycling, cross-country skiing or swimming. Not surprisingly, 71% of the patients reported problems related to the affected upper limb, such as muscle weakness and/or joint stiffness during the aforementioned activities.

MANAGEMENT OF ONE HUNDRED SEVENTY-ONE OPERATIVE AND NONOPERATIVE OBSTETRICAL BIRTH PALSIES AT THE LOUISIANA STATE UNIVERSITY HEALTH SCIENCES CENTER

OBJECTIVE

The management of obstetrical brachial plexus injury, often called birth palsy, remains one of the most controversial topics in pediatric neurosurgery. Most birth palsies have acceptable spontaneous recoveries, whereas only a minority require surgical intervention. A selective approach for surgery was used in this Louisiana State University Health Sciences Center (LSUHSC) series, for which the operative rate was 9%. At LSUHSC, the patient with obstetrical brachial plexus injury is followed for 6 to 9 months before surgery, which is performed if there is no satisfactory biceps and/or shoulder function.

METHODS

This is a retrospective analysis of 169 patients with 171 palsies referred to LSUHSC for possible surgery. There were 76 patients with 77 birth palsies managed operatively and nonoperatively at LSUHSC between 1975 and 1991. An additional 93 patients with 94 palsies who were managed between 1992 and 2003 were included in this analysis. The results of initial and follow-up examinations using Eng's criteria for impairment ratings (IRs) were available for 151 of 171 (88%) nonoperative and operative obstetrical brachial plexus injuries managed between 1975 and 2001.

RESULTS

Fifty-two percent of the nonoperative patients evaluated at an initial visit had an IR of 4 or 5, which represents very poor function by comparison to IR of 1 in the Eng scale, which represents almost no abnormality. The percentage of patients in this category (4–5) improved to 30% after follow-up visits. For the 16 operative cases, the initial and follow-up percentages of patients with IRs of 4 or 5 were 67% and 22%, respectively. Ultimately, 47% of the nonoperative patients achieved a grade 2 IR after follow-up compared with 17% of the operative patients.

CONCLUSION

Using this selective approach at LSUHSC, in which the operative rate was 9%, acceptable outcomes were obtained both in patients not having surgery and also in those having surgical intervention.

Etiological risk factors for brachial plexus palsy

AIM

To investigate risk factors for brachial plexus palsy in newborns. We analyzed 45 544 live-born children, born over a nine-year period from January 1, 1996 to December 31, 2004.

METHODS

The analysis was retrospective and based on the medical documentation of the Clinic for Gynecology and Obstetrics, Clinic for Neurology, and Clinic for Physical Medicine and Rehabilitation of the University Clinical Center Tuzla. We compared study and control groups of newborns. Rates among groups were compared using Chi-square, with significance at p < 0.05, and with significance at p < 0.01.

RESULTS

Examining epidemiological characteristics, 86 newborns with brachial plexus palsy had been recorded, thus, the prevalence was 1.86 per 1000 live-born children. Analyzing maternal and neonatal factors, and the labor pattern itself, it was found that the highest factors of risk for brachial plexus injury were birth weight of over 4000 g, a precipitous second stage of labor (<15 minutes), and vacuum-extractor assisted labor. Brachial plexus palsy was more frequent when the mothers were overweight, with a body mass index >or=29 kg/m2. None of the parturient women, whose newborns were diagnosed with brachial plexus palsy, had external conjugate diameter <18 cm. Newborns delivered vaginally were not diagnosed with a higher frequency of brachial plexus palsy when compared to newborns who were delivered by cesarean section, but newborns who were vaginal breech-delivered were diagnosed to have a higher incidence of brachial plexus palsy. Newborns whose mothers were older than 35 years were diagnosed to have brachial plexus palsy more frequently, but a statistically significant difference between primiparas and multiparas was not found. A total of 39 newborns (45.2%) were diagnosed with a fracture of the clavicle, which was the most frequently combined damage with brachial plexus injury. Forty-two newborns (48.8%) had an Apgar score of <or=7 in the first minute after delivery, which indicates intrapartal fetal distress and is an indication of the traumatic nature of these deliveries. The average birth weight of newborns with brachial plexus damage was 3858.1+/-587.7 g, which for an average gestational age of 38.8+/-1.8 weeks, corresponds to eutrophic newborns. Both male and female newborns were diagnosed to have brachial plexus palsy comparably frequently, and almost all deliveries (97.7%) were initiated spontaneously. The majority of newborns were born between the hours of 02:00 and 03:00 and between the hours of 14:00-15:00.

Shoulder dystocia without versus with brachial plexus injury: A case–control study

OBJECTIVE

To delineate factors that differentiate shoulder dystocia with and without brachial plexus injury (BPI).

STUDY DESIGN

A case-control study culled from an established shoulder dystocia database. Cases of shoulder dystocia-related BPI were identified and matched (1:1) with a control group of shoulder dystocia in which BPI did not result. Odds ratios (OR) and 95% confidence intervals (CI) were calculated.

RESULTS

From 1980 to 2002, there were 89 978 deliveries with 46 cases of dystocia and BPI. The rate of dystocia with BPI was 0.5 per 1000 births and of permanent BPI, 0.9/10 000 deliveries. The two groups were similar for maternal demographics, diabetes, gestational age, induction, use of epidural, the duration of labor, operative vaginal delivery, rate of macrosomia, and maneuvers used to relieve the dystocia. Fracture of the clavicle occurred significantly less often among those without (2%) vs. with BPI (17%; OR 0.10, 95% CI 0.01, 0.88).

CONCLUSIONS

Neither antepartum nor intrapartum factors can differentiate the patient who will have shoulder dystocia with vs. without BPI.

Severe chronic morbidity following childbirth

Three special, chronic morbidities of childbirth are reviewed with the most up-to-date knowledge in this article. Firstly, obstetric fistulas secondary to prolonged obstructed labour are still prevalent tragedies in underdeveloped countries. The damage is not only physical but psychosexual and social. The surgical skill and technology required to prevent and to treat obstetric fistulas are simple, but culture-social antagonism, geographic distance, political instability and financial constraint have to be overcome before effective management can take place. Congenital brachial plexus palsy is associated with shoulder dystocia and macrosomia, and both excessive exogenous traction and strong endogenous pushing forces contribute to its occurrence. As shoulder dystocia and macrosomia are not easily predictable, regular training and drill is essential to ensure proper management of shoulder dystocia. Most of the babies with brachial palsy will recover in 3 months but a minority of patients will suffer a more severe degree of damage, requiring early micro-neurosurgical intervention. Finally, although birth asphyxia is not the major cause of cerebral palsy, brain injury resulting from acute intrapartum hypoxic-ischemic insult is potentially alleviated by early neonatal hypothermic therapy. Both clinical and radiological assessments are essential in selecting suitable candidates for this innovative neuroprotective strategy.

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.

A case of congenital bilateral absence of elbow flexor muscles: review of differential diagnosis and treatment

A 1-year-old boy presented to us with congenital inability to flex his elbow. He had bilaterally absent biceps brachii and brachialis muscles, a rare condition. We performed pedicle latissimus dorsi musculocutaneous flaps to the left and right volar upper arm at 21 and 24 months of age, respectively, to create elbow flexors. By 4 years of age, he had excellent elbow flexion bilaterally with strength grade in excess of 4.5. In addition to discussing our patient's treatment options, we discuss other potential causes of weak elbow flexion when faced with this clinical dilemma.

Shoulder dystocia

Using an evidence-based, medical approach, the strengths and pitfalls of the causation- and standard-of-care-based arguments proffered by plaintiff and defense counsel in shoulder dystocia- associated birth injury litigation are reviewed based on medical plausibility. The role of the expert witness as arbiter of the relationship between medical care rendered and the untoward outcome of such care is distinguished from that of other court members. Proposed solutions to the medical malpractice litigation crisis are also examined in light of relevant differences in the pathogenetic bases for birth injuries of various types.

Labour characteristics and neonatal Erb's palsy

OBJECTIVE

To determine risk factors for Erb's palsy, with a focus on graphic labour patterns.

DESIGN

A case-control study.

SETTING

New York City.

SAMPLE

A total of 45 consecutive cases of Erb's palsy and 90 controls.

METHODS

Pregnancies and labours of neonatal Erb's palsy cases were compared with 90 controls using univariate and multiple logistic regression analysis.

MAIN OUTCOME MEASURES

Erb's palsy and shoulder dystocia.

RESULTS

Mothers of children with Erb's palsy had a higher term body mass index and more gestational diabetes than those of controls. Even cases without diabetes had higher blood glucose values after a 50-g glucose challenge than did controls. Cases had a higher birthweight and a lower ratio of head-to-thoracic circumference than controls. Shoulder dystocia occurred in 67% of cases and in 2% of controls (P = 0.001). Only 46% of labours had a completely normal dilatation pattern. In a multiple logistic regression model, variables independently associated with brachial plexus injury were long deceleration phase of labour, long second stage, high birthweight, black race, and high neonatal or maternal body mass.

CONCLUSIONS

Erb's palsy was frequently preceded by abnormal labour and shoulder dystocia; however, a substantial proportion of cases occurred after normal labour and delivery. Predictive models will be necessary to determine to what extent careful monitoring of the terminal portion of dilatation and of fetal descent and incorporation of maternal body mass and race (all independent risk factors in this study) will help identify fetuses at risk for brachial plexus palsy.

The risk of shoulder dystocia related permanent fetal injury in relation to birth weight

OBJECTIVE

To examine birth weight related risks of fetal injury in connection with shoulder dystocia.

STUDY DESIGN

The investigation was based on a retrospective analysis of 316 fetal neurological injuries associated with deliveries complicated by arrest of the shoulders that occurred across the United States.

RESULTS

The study revealed that the distribution of birthweights for the high risk shoulder dystocia population differs from the standard birthweight distribution. The relative difference per birthweight interval is used to adjust an assumed 1:1000 baseline risk of injury due to shoulder dystocia following vaginal deliveries. These adjusted risks show a need to consider new thresholds for elective cesarean delivery.

CONCLUSIONS

Current North American and British guidelines, that set 5000 g as minimum estimated fetal weight limit for elective cesarean section in non-diabetic and 4500 g for diabetic gravidas, may expose some macrosomic fetuses to a high risk of permanent neurological damage. The authors present the opinion that the mother, having been informed of the risks of vaginal versus abdominal delivery, should be allowed to play an active role in the critical management decisions.

Shoulder dystocia and injuries: prevention and management

PURPOSE OF REVIEW

Shoulder dystocia is an obstetric emergency that is often unpredictable and unanticipated. Despite the identification of various clinical risk factors, our ability to predict and prevent shoulder dystocia is very limited. Effective and timely clinical management is essential to offer the best chance of a satisfactory outcome.

RECENT FINDINGS

Upon diagnosis of the condition, a team working in tandem to resolve the problem is very effective. Use of the McRoberts maneuver, application of suprapubic pressure, with an adequate episiotomy allow resolution of over 50% of cases, with a low risk of fetal injury. Secondary maneuvers include rotation of the shoulders and delivery of the posterior shoulder. These are technically more challenging and may be associated with a higher risk of fetal injury. More drastic action may be considered in dire cases where even secondary maneuvers fail. These include the Zavanelli maneuver, symphysiotomy or iatrogenic clavicular fracture. These techniques, while seldom required, may be lifesaving in extremely severe cases.

SUMMARY

Upon resolution of the clinical event, it is essential to document the entire event, and to discuss the clinical problem and management with the parents. These actions will reduce the risk of medical litigation, and improve patient satisfaction with clinical care.

Risk factors for brachial plexus injury with and without shoulder dystocia

OBJECTIVE

To ascertain whether brachial plexus palsy (BPP) that occurs without shoulder dystocia (SD) represents a traction injury during unrecognized SD or a natural phenomenon with a different mechanism of injury, we compared risk factors and outcomes between SD-associated and non-SD-associated BPP.

STUDY DESIGN

Neonates with BPP after cephalic vaginal delivery were pooled from all deliveries at Johns Hopkins (June, 1993-December, 2004) and a dataset of litigated permanent BPP from multiple institutions (1986-2003), grouped by SD association based on clinician documentation and compared by using Fisher exact and t tests.

RESULTS

Thirty percent of 49 non-SD-BPP and 11% of 280 SD-BPP lacked all risk factors for SD (P = .002). Compared with SD-BPP infants, non-SD-BPP infants were average weight (P < .001) and had cord pH less than 7.10 (P = .01) more commonly and exhibited a trend toward posterior shoulder involvement (P = .06). Nearly all non-SD-BPP were temporary, whereas more than 90% of permanent BPP were associated with SD (odds ratio 17, 7.3-39.6).

CONCLUSION

Non-SD-BPP is uncommon and likely mechanistically distinct from SD-BPP. Risk factors, birth weight, fetal acidosis, posterior arm involvement, and injury severity distinguish between shoulder dystocia-related brachial plexus injuries and those not recorded as such.

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.

Correlation of birth injury with maternal height and birthweight

BACKGROUND

Infant or maternal injury during vaginal delivery is a constant threat to all involved, but difficult to predict.

OBJECTIVE

To estimate the risk of birth injuries in an institution favouring trial of vaginal birth when there was doubt of the best mode of delivery.

DESIGN

A retrospective cohort study.

SETTING

University Hospital.

POPULATION

Singleton 14,359 vaginal deliveries in cephalic presentation during 5(1/2) years.

METHODS

The total caesarean section rate during this period was 9%. The likelihood of injury was evaluated by logistic regression analysis with injury as the dependent variable and maternal height and child birthweight as explanatory variables in birth injury risk estimation.

MAIN OUTCOME MEASURES

Infant injury defined as one of the following: shoulder dystocia, clavicle fracture or brachial plexus injury; and maternal injury as anal sphincter rupture (ASR).

RESULTS

There were a total of 318 infant injuries in 282 infants and 423 ASRs. A strong correlation was found between injury and both fetal macrosomia and short maternal stature, but macrosomia was a stronger indicator of injury. Birth injury risk estimation curves were constructed based on maternal height and birthweight.

CONCLUSIONS

The present results confirm a strong correlation between fetal macrosomia and short maternal stature and the likelihood of injury during vaginal birth. Risk estimation curves were constructed that might be of great value for the obstetrician in choosing the mode of delivery in these cases.

Brachial plexus injury: a 23-year experience from a tertiary center

OBJECTIVE

The purpose of this study was to analyze the data on brachial plexus injury and its relationship with shoulder dystocia from a tertiary center for a 23-year period.

STUDY DESIGN

A review of the logbooks on labor and delivery and the nursery and the International Classification of Diseases codes identified all newborn infants with brachial plexus injury who were delivered at our center.

RESULTS

During the 23 years (1980-2002), there were 89,978 deliveries, of which there were 85 cases of brachial plexus injury (1/1000 births) with vaginal delivery. The injury was permanent (> or =1 year) in 12% of the cases, and only 2 cases have been litigated. Newborn infants that weighed > or =4 kg were significantly more common among those infants who had shoulder dystocia and brachial plexus injury than those infants without injury (odds ratio, 6.55; 95% CI, 2.30, 18.63). The rate of permanent brachial plexus injury was similar between the 2 groups.

CONCLUSION

A case of brachial plexus injury occurs 1 time in every 1000 births, is permanent in 1 of every 10,000 deliveries, and is litigated 1 time for every 45,000 deliveries. The infrequent nature of injury may preclude prevention.

Birth injuries of the brachial plexus

Birth injuries of the brachial plexus are fairly common, but the majority of affected newborns make quick recoveries without any specific intervention. A minority suffer more severe injuries that lead to varying degrees of life-long disability. Happily, modern microsurgical techniques permit reconstruction of certain plexus injuries and, in carefully selected patients, can restore voluntary activity to target muscle groups. To what degree reanimation of paralyzed muscles improves function and quality of life for these children is a more important matter that has not yet been addressed at the level of modern standards of evidence. Brachial plexus reconstruction is only a first step in the multidisciplinary process needed to optimize long-term functional outcomes for severely affected infants.

Patient choice cesarean: an evidence-based review

Primary elective cesarean performed on a patient's request now comprises 4% to 18% of all cesareans and 14% to 22% of elective cesareans in reported series. Patients most commonly choose cesarean because of tocophobia, or fear of childbirth. Almost two thirds of obstetricians surveyed are willing to perform cesarean on request, citing decreased risk of pelvic floor or fetal injury, maintenance of sexual functioning, and physician and patient convenience. Contrasting these beliefs are the limited available data on short- and long-term maternal and perinatal morbidity and mortality that generally favor vaginal delivery. Moreover, comprehensive economic impact assessments of cesarean on request are lacking, and professional organizations do not agree on the ethics of offering patient choice cesarean.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to list the reasons that women and obstetricians choose elective cesarean delivery, to outline the ethical aspects of cesarean delivery, and to describe the material and fetal morbidity and mortality associated with cesarean delivery compared to vaginal delivery.

Erb's palsy - Who is to blame and what will happen?

Erb's palsy is initially frightening. The infant's arm hangs limply from the shoulder with flexion of the wrist and fingers due to weakness of muscles innervated by cervical roots C5 and C6. Risk factors are macrosomia (large baby) and shoulder dystocia. However, Erb's palsy may occur following cesarian section. The experience of the delivering physician may not influence the risk of Erb's palsy (0.9 to 2.6 per 1000 live births). Differential diagnosis includes clavicular fracture, osteomyelitis and septic arthritis. Fortunately, the rate of complete recovery is 80% to 96%, especially if improvement begins in the first two weeks. Recommended treatment includes early immobilization followed by passive and active range of motion exercises (although there is no proof that any intervention is effective). For the few infants with no recovery by three to five months, surgical exploration of the brachial plexus may improve the outcome. Three infants with Erb's palsy who illustrate variations in the evolution of this disorder are presented.

Birth injuries of the brachial plexus

Birth injuries of the brachial plexus are fairly common, but most affected newborns make quick recoveries without any specific intervention. A minority suffer more severe injuries that lead to varying degrees of life-long disability. Modem microsurgical techniques permit reconstruction of certain plexus injuries and, in carefully selected patients, can restore voluntary activity to target muscle groups. The degree to which reanimation of paralyzed muscles improves function and quality of life for these children is a more important matter that has not yet been addressed using modern standards of evidence. Brachial plexus reconstruction is only a first step in the multidisciplinary process needed to optimize long-term functional outcomes for severely affected infants.

Prediction of brachial plexus stretching during shoulder dystocia using a computer simulation model

OBJECTIVE

The purpose was to study the impact of maternal endogenous and clinician-applied exogenous delivery forces on brachial plexus stretching during a shoulder dystocia event.

STUDY DESIGN

A computer software crash dummy model (MADYMO, version 5.4, TNO Automotive, Delft, The Netherlands) was modified on the basis of established maternal pelvis and fetal anatomic specifications. The brachial plexus was modeled as a spring, with mechanical properties that were based on previously reported experimental data. Increasing amounts of endogenous or exogenous loading forces were applied until delivery of the anterior fetal shoulder occurred. Brachial plexus deformation was assessed as percent stretch in the nerve (Change in length/Original length x 100).

RESULTS

With lithotomy positioning, both maternal endogenous and clinician-applied exogenous delivery forces were associated with brachial plexus stretching (15.7% vs 14.0%, respectively). McRoberts positioning reduced needed loading forces for delivery and resulted in 53% less brachial plexus stretch (6.6%). Downward lateral displacement of the fetal head was associated with a 30% increase in brachial plexus stretch (18.2%) compared with axial positioning of the head (14.0%).

CONCLUSION

Brachial plexus stretch varied as a result of the load required for delivery, the source of the applied force, pelvic orientation, and fetal head positioning. Maternally derived and clinician-applied delivery forces can both lead to brachial plexus deformation when shoulder dystocia is encountered. The McRoberts maneuver can reduce brachial plexus stretching. Management of fetal head position may also be important in reducing unnecessary brachial plexus stretch.

Intrapartum risk factors for permanent brachial plexus injury

OBJECTIVE

The purpose of this study was to compare maternal, neonatal, and second stage of labor characteristics in shoulder dystocia deliveries that result in permanent brachial plexus injury with shoulder dystocia deliveries that result in no injury.

STUDY DESIGN

Our cases were culled from a database of deliveries that resulted in permanent brachial plexus injuries and matched to control cases that were taken from a database of consecutive shoulder dystocia deliveries from one hospital. Deliveries that resulted in injury were excluded from the control cases; those cases with no recorded shoulder dystocia were excluded from the cases. Matching was for birth weight (+/-250 g), parity, and diabetic status. Rates of precipitous and prolonged second stage, operative delivery, neonatal depression, and average number of shoulder dystocia maneuvers used were compared between the two groups with chi(2) test, Fisher exact test, and the Student t test; a probability value of <.05 was considered significant.

RESULTS

There were 80 matched patients, of which 26 patients were nulliparous and 11 patients were diabetic. Mothers of the uninjured group were younger than those of the injured group (23.7+/-6.2 years vs 27.4+/-5.1 years, P<.001). The injured group had a significantly higher rate of 5-minute Apgar scores of <7 (13.9% vs 3.8%, P=.04). Differences in maternal weight, body mass index, height, race, gestational age, average number of maneuvers, head-to-body delivery interval, operative delivery rate, prolonged second stage rate, precipitous second stage rate, and sex were not significant between groups. The rates of precipitous second stage for both groups (28.0% injured and 35.0% uninjured) were more than triple the rates of prolonged second stage (9.5% injured and 11.3% uninjured).

CONCLUSION

No characteristic of second-stage of labor predicts permanent brachial plexus injury. Precipitous second stage is the most prevalent labor abnormality that is associated with shoulder dystocia.

Congenital brachial palsy: incidence, causes, and outcome in the United Kingdom and Republic of Ireland

OBJECTIVES

To determine the incidence and study the causes and outcome of congenital brachial palsy (CBP).

DESIGN

Active surveillance of newborn infants using the British Paediatric Surveillance Unit notification system and follow up study of outcome at 6 months of age.

SETTING

The United Kingdom and Republic of Ireland.

PARTICIPANTS

Newborn infants presenting with a flaccid paresis of the arm (usually one, rarely both) born between April 1998 and March 1999.

MAIN OUTCOME MEASURES

Extent of the lesion at birth and degree of recovery at 6 months of age.

FINDINGS

There were 323 confirmed cases giving an incidence of 0.42 per 1000 live births (1 in 2300). Significant associated risk factors in comparison with the normal population were shoulder dystocia (60% v 0.3%), high birth weight with 53% infants weighing more than the 90th centile, and assisted delivery (relative risk (RR) 3.4, 95% confidence interval (CI) 2.9 to 3.9, p = 0.0001). There was a considerably lower risk of CBP in infants delivered by caesarean section (RR 7, 95% CI 2 to 56, p = 0.002). At about 6 months of age, about half of the infants had recovered fully, but the remainder showed incomplete recovery including 2% with no recovery. The relative risk of partial or no recovery in infants with extensive lesions soon after birth compared with those with less extensive lesions was 11.28 (95% CI 2.38 to 63.66, p = 0.000005).

CONCLUSIONS

The incidence of CBP in the United Kingdom and Republic of Ireland is strikingly similar to that previously reported nearly 40 years ago. Most cases are due to trauma at delivery, which is not necessarily excessive or inappropriate. Given the uncertainty about the appropriate management of these infants, serious consideration should be given to a formal clinical trial of microsurgical nerve repair.