04/06/2019
OBSTETRIC BRACHIAL PLEXUS INJURIES
Obstetric brachial plexus palsy is defined as a flaccid paresis of an arm at birth, with the passive range of motion being greater than the active range of motion. The incidence rate of obstetric brachial plexus injury is approximately 0.15% in the United States, but can vary between 0.04-0.6 percent according to other reports. Almost 80% of these injuries involve the cervical spine C5-C6 nerve roots (Erb-Duchenne palsy). Other common injuries are Klumpke paralysis, facial nerve injuries etc. During delivery, maneuvers involving twisting and extension of the head can result in stretching of the neck and may be responsible for the obstetric brachial plexus injuries. Lithotomy positioning during the delivery can greatly increase the brachial plexus stretch, whereas McRobert’s maneuver resulted in 53% less stretch.
The obstetric brachial plexus injuries can be prevented and managed with multidisciplinary approach involving obstetricians (by applying McRobert’s maneouver timely in case of shoulder dystocia), neonatologist (timely recognising the magnitude of the problem and referring to the pediatric neurologist), pediatric neurologist (assessment of the level and type of injuries with help of nerve conduction studies and electromyography & treatment accordingly) and pediatric neurosurgeon (for treatment of complete root avulsions). With the help of multidisciplinary approach these injuries tend to be transient with 70-95% of the cases resolving within a year. However, approximately 5-8% of the cases result in the persistent and permanent injuries. The injuries that involve cervical spine- thoracic vertebrae C8-T1 nerve roots (Klumpke palsy) are more likely to persist with only 40% resolving within a year.
