Neonatal brachial plexus palsy caused a mechanical injury at the time of birth. Erb’s palsy results from neuronal damage to the upper C5 and C6 nerves. The clinical presentation includes partial or full paralysis of the arm and often accompanied by loss of sensation. Klumpke’s palsy causes paralysis of the forearm and hand muscles as a result of mechanical damage to the lower C8 and T1 nerves. This neuronal lesion affects primarily the wrist and fingers, and often the position of the hand is “clawed.” The clinical manifestations range from mild injuries with complete resolution to severe and permanent disability. Overall, patients have a high rate of spontaneous recovery (66-92%).
Applying to both: Brachial Plexus Injury from Birth Trauma; Obstetric Brachial Plexus Palsy.
The first description of (a bilateral) obstetric brachial plexus palsy was reported by the Scottish obstetrician William Smellie (1697-1763) in 1752 in a newborn after difficult labor. In 1861, the famous French neurologist Guillaume Benjamin A. Duchenne (de Boulogne) (1806-1875) analyzed four newborns with brachial palsy and came up with the correct pathogenesis (traction injury). The German neurologist Wilhelm Heinrich Erb (1840-1921) further investigated this topic and concluded in 1875 that a radicular nerve lesion at the level C5 and C6 was responsible for the palsy. At the same time, the American-born neurologist Augusta Marie Dejerine-Klumpke (1859-1927) described lower trunk lesions of the brachial plexus associated with palsy and Horner Syndrome resulting from C8 and T1 lesions.
The incidence of obstetric brachial plexus palsy is estimated at 1-3 cases per 1000 live births in industrial countries. Males are more commonly affected than females. The right side is more often affected than the left. In countries with lower average birth weights, it is most likely less frequent.
There is no genetic component as it is a traumatic brachial plexus injury. However, a history of a previous child with brachial plexus injury carries a high-risk of repetition in the next child (although there is no genetic background for this observation).
Clinical findings and history of difficult vaginal delivery (shoulder dystocia or breech presentation). MRI or CT-myelography is used to visualize the lesions.
Four types of brachial plexus injuries are known: avulsion is the most severe form where the nerve is torn from the spinal cord. Rupture denotes the state where the nerve is torn, but not at the spinal cord level. Neuroma describes the state where the nerve has been torn and healed, but scar tissue affects proper signal conduction in the affected nerve. Neurapraxia, the most common form of brachial plexus injury, is caused by the damaged, ...