Nerve Disorders Flashcards
Types of Brachial plexus disorders
Lateral stretch
Congenital anatomical variation
Erb’s palsy (C5-6, upper plexus)
Klumpke’s palsy (C8-T1, lower plexus)
Neurapraxia
Reversible loss of nerve conduction
Will have recovery
No physical disruption
Axonomesis
Variable severity
Physical disruption of nerves but preserved endonerium around axons
Neurotmesis
Most severe
Complete physical disruption of nerves
Avulsion
Preganglionic neurotmesis
Rupture
Postganglionic neurotemesis
Brachial Plexus Palsy RF
Shoulder dystocia
Multiparous mother
Large birth wt (>4500g)
Prior infant with Birth BPP
Clinical features of Brachial Plexus palsy
Lack of AROM of arm
Lack of sensation in arm
Contractures common
Brachial plexus palsy exam
Absent reflexes/motor func/sensation in involved distribution Moro reflex asymmetry ROM/contracturs Decreased muscle bulk Torticollis
Electrodiagnosis in Brachial Plexus Palsy
H reflexes and F waves to look at proximal function
Sensory NCS in BPP
Response present in area of sensory loss indicates preganglionic lesion
Guillan-Barre Syndrome
Acute or subacute inflammatory process of the peripheral nervous system resulting in demyelination of axons
Guillan-Barre Risk Factors
Campylobacter jejuni CMV EBV VZV Mycoplasma pneumonia HIV
Guillan-Barre Clinical Features
Ascending weakness from LE Paresthesia and numbness Vibration/position sense changes Ataxia Autonomic sx Respiratory involvement Pain in extremities and back Areflexia
LP findings in GBS
Protein >45 mg/dL
MRI of lumbosacral spine in GBS
Gadolinium will show enhancement of nerve roots
EMG/NCS in GBS
Reduced conduction velocities
Conduction block or temporal dispersion
Prolonged latencies
Prolonged or absent F wave
Hereditary motor sensory neuropathy OR Charcot Marie Tooth Dz (CMT HMSN)
Group of d/o with a chronic motor and sensory polyneuropathy in the upper and lower limbs resulting progressive symmetrical distal muscle weakness, atrophy, sensory loss and depressed DTR’s
Etiology of CMT HMSN
Autosomal dominant (CMT 1, CMT2) Autosomal recessive (CMT4) X-linked (CMTX)
CMT HMSN Clinical Features
Distal muscle wasting and weakness Vibration and proprioception loss Depressed or absent DTR's Stork leg, inverted champagne bottle Pes cavus (high arch) Hammertoes Hindfoot varus Enlarged and palpable peripheral nerves Thoracic scoliosis Sensory gait ataxia
Unique features to X-linked CMT HMSN
Intellectual disability
Sensorineural hearing loss
Natural history of CMT HMSN
Onset 1st-3rd decades
Slowly progressive weakness
Normal lifespan
EMG findings in CMT HMSN
Slow conduction velocity
