DIFFERENTIAL
■ Plexopathies: On detailed examination these can be mapped to the brachial
or lumbosacral plexus.
■ Symptoms will involve distal and proximal extremity.
■ May be due to trauma, radiation, malignancy, viral infection (lumbosacral)
SYMPTOMS/EXAM
■ Pain and weakness in multiple peripheral nerves (eg,. sciatic, common
peroneal, radial, femoral)
■ Asymmetric
DIAGNOSIS
■ Electrodiagnostic studies
■ Sural nerve biopsy if diagnosis in question
TREATMENT
■ Treat underlying disorder (eg, steroids for vasculitis).
■ Treat associated neuropathic pain (eg, amitriptyline, carbamazepine,
gabapentin).
Amyotrophic Lateral Sclerosis
ALS is a disorder characterized by upper motor neuron disease in addition to
lower motor neuron pathology.
PATHOPHYSIOLOGY
■ Anterior horn cell neuronopathy →peripheral nerve findings.
■ Loss of Betz cells in the CNS motor cortex →upper motor neuron findings.
SYMPTOMS/EXAM
■ Lower motor neuron involvement
■ Muscle fasciculations and atrophy
■ Muscle cramps
■ Asymmetric distal weakness
■ Upper motor neuron involvement
■ Hyperreflexia and clonus
■ Spasticity
■ Positive Babinksi
■ Serious complications and or death result from progressive respiratory
muscle weakness (→respiratory failure) or dysphagia (→ aspiration).
DIAGNOSIS
■ Electrodiagnostic testing
TREATMENT
■ Supportive therapy
■ Disease-modifying agent (rizulon)
NEUROLOGYThe hallmark of ALS is the
presence of both upper motor
neuron and lower motor
neuron signs and symptoms.