Permanent Erb's palsy: a lack of a relationship with obstetrical risk factors.

Our objective was to investigate the association between permanent Erb's palsy and the presence of historic obstetrical risk factors. Cases of documented permanent Erb's palsy from our national registry of children with Erb's palsy were extracted and analyzed for the purpose of this descriptive study. Maternal and neonatal records were reviewed for demographic data, prenatal care, labor characteristics, delivery outcome, and long-term follow-up. Sixty-three infants with permanent Erb's palsy were identified. Seventeen (27.0%) mothers were nulliparous. Mean +/- SD (range) gestational age at delivery and birthweight were 39.9 weeks +/- 1.3 (37-43) and 4501 g +/- 625 (3352-6905), respectively. Maternal and perinatal characteristics of these cases were (n [%]): nondiabetic-56 (89%); weight gain <40 lb-48 (76%); normal labor-57 (91%); 2nd stage <2.0 hr-54 (86%); midpelvic procedure-13 (21%); and shoulder dystocia-59 (94%). There were no statistically significant differences between patients with birthweight >4500 g (n = 26 [41%]) and those with birthweight < or =4500 g (n = 37 [59%]). These data suggest that historic risk factors for neonatal brachial plexus injury may not be associated with permanent Erb's palsy.

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

OBJECTIVE: Our purpose was to determine whether Erb's palsies occurring in the absence of shoulder dystocia differ from those occurring after shoulder dystocia. STUDY DESIGN: We compared the time course of resolution and incidence of persistent injury at 1 year of age in 17 cases of Erb's palsy without shoulder dystocia and 23 cases associated with shoulder dystocia. RESULTS: The rate of persistence at 1 year was significantly higher in those Erb's cases without identified shoulder dystocia, 7 of 17 (41.2%) versus 2 of 23 (8.7%), p = 0.04. These cases of Erb's palsies also took longer to resolve (6.4 +/- 0.9 vs 2.6 +/- 0.7 months, p = 0.002), had a higher rate of associated clavicular fracture (12 of 17 vs 5 of 23, p = 0.006), and were more likely to occur in the posterior arm (10 of 15 vs 4 of 21, p = 0.009). CONCLUSIONS: Erb's palsy occurring without shoulder dystocia may be a qualitatively different injury than that occurring with shoulder dystocia.