Neonatal brachial plexus palsy caused by obstetric trauma.
Applying to both: Brachial Plexus Injury from Birth Trauma; Obstetric Brachial Plexus
For Erb Palsy: Duchenne Erb Palsy.
For Klumpke Palsy: Dejerine-Klumpke Palsy/Paralysis/Syndrome.
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.
No genetic component (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 (no genetic background).
Clinical findings and history of difficult vaginal delivery (shoulder dystocia or breech
presentation). MRI or CT-myelography are 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, but not torn nerve.
The brachial plexus is made up of the nerves exiting the spinal cord from root
C5-T1. They form the three trunks: upper (formed by C5 and C6), middle (formed by C7), and
lower trunk (formed by C8-T1). Each trunk then divides further to form the cords and finally
subdivide further to form radial, median, and ulnar nerve. The injury to the brachial plexus may
range from mild palsy to flaccid paralysis.
Four different types of brachial plexus palsy have been defined:
Erb (-Duchenne) palsy is caused by nerves arising from C5 and C6.
(Dejerine-) Klumpke palsy results from injury to the nerve fibers at the levels C8 and T1
(although it is controversial if pure C8/T1 lesions are possible). This lesion is rare.
Lesions affecting C5, C6, and C7 result ...