Lumbosacral plexus lesions are usually
due to obstetrical trauma. They are usually associated with breech presentation.
Evidence of trauma in other areas may be present.
Peripheral nerve damage is
usually due to local nerve trauma. Radial nerve damage has been associated
with fracture of the humerus, restricted uterine positions, difficult
delivery, or the use of blood pressure cuffs.
An area of cutaneous discoloration in the trajectory of the radial nerve
or in the posterior interosseous branch may be present.
Median nerve injury in the
antecubital fossa is usually due to brachial artery puncture. Median nerve
injury is more common in small neonates.
Sciatic nerve injury occurs
after injection to the buttocks, prolonged pressure on the buttocks, or
infusion of drugs into the umbilical artery. The mechanism of injury with
injections to the buttocks is the inflammation associated with the injected
substance and not trauma to the nerve by the needle stick as was initially
considered. Necrosis of the buttocks may be associated with thrombosis
of the inferior gluteal artery. The mechanism of sciatic nerve injury
due to infusion of drugs into the umbilical artery is probably thrombosis
of the inferior gluteal artery. This artery irrigates the sciatic nerve.
Peroneal nerve injury may be
due to compression by uterine bands (Figure 266.1), an ill-applied foot
board, or intravenous fluid infiltration.
Figure 266.1.— Amniotic band affecting the leg
above the ankle.
to the peripheral nerves do not have any specific treatment other than
discontinuing the mechanism of injury if possible. Most neonates with
peripheral nerve injuries recuperate with physical and occupational therapy.