Chapter 23: NEUROLOGY

NEUROLOGIC TESTS, PARALYSES & PALSIES

SOMATOSENSORY EVOKED POTENTIALS (SEP)

ONLY order a somatosensory evoked potentials (SEP) test if you are concerned about a demyelinating process.

MNEMONIC: S.E.P. = SEParation = Testing for SEParation of the myelin from the nerve!

NERVE CONDUCTION VELOCITIES

ONLY order nerve conduction velocities testing when concerned about a peripheral neuropathy.

ELECTROMYOGRAM (EMG)

An electromyogram (EMG) is used to test for abnormal MUSCLE activity (may be due to a neuropathy).

PEARL: Use this in patients suspected of having a muscular dystrophy.

MAGNETIC RESONANCE IMAGING (MRI)

Magnetic resonance imaging (MRI) is great for detailed imaging of the spinal cord and brain. It will tell you pretty much everything you want to know, but it’s expensive and takes longer.

COMPUTER TOMOGRAPHY SCAN (CT SCAN)

A computer tomography scan (CT scan) is cheap and fast (good for the ER). It’s great if you’re looking for an acute hemorrhage, evidence of increased intracranial pressure, and sometimes even a brain tumor.

SPINAL ULTRASOUND

When looking for neural tube defects, a spinal ultrasound is a great option in newborns. It can actually be done up until a child is 6 months of age.

ERB’S PALSY AND KLUMPKE PALSY

Erb’s Palsy and Klumpke Palsy are both associated with birth trauma, BREECH delivery, caesarian sections, clavicle fractures and LGA births.

PEARLS: Images of the arm/hand deformities MAY look the same. The only way to discern which palsy the child has is to evaluate the patient for specific neurologic limitations. If the baby is able to grasp, it is an ERB PALSY. If you note a claw hand deformity in a patient able to flex at the elbow, it is a KLUMPKE PALSY.

• ERB PALSY (AKA ERB’S PALSY): Brachial plexus injury at C5–6 or –7, resulting in paralysis of the UPPER ARM. There is a “waiter’s tip” configuration if C7 is involved. There is UNILATERAL DIAPHRAGMATIC PARALYSIS in about 5% of cases.
  • IMAGE: www.pbrlinks.com/ERBSPALSY1
  • PEARLS: The grasp and extension of the hand are INTACT. Respiratory distress can result due to phrenic nerve injury (look for a broken clavicle) resulting in unilateral diaphragmatic paralysis. It is often associated with LGA babies, breech deliveries, and C-sections.
  • MNEMONIC: Imagine a WAITER named “ERB” subtly asking for a tip. He CAN grasp the money you give to him.
• KLUMPKE PALSY: Brachial plexus injury, but lower (C8-T1). This affects the LOWER arm and hand. It carries a worse prognosis because the nerves are typically torn. It results in a CLAW HAND deformity in which there is an INABILITY TO GRASP. Horner’s syndrome (below) is usually present. Less common than Erb’s palsy.
  • MNEMONIC: The hand is stuck in a configuration in which the hand has a KLUMP OF AIR in it.
  • IMAGE: www.pbrlinks.com/ERBKLUMPKE shows Erb’s and Klumpke’s together.