Peripheral Neuropathies Flashcards
Define peripheral neuropathy
damage/disease involving nerves of the PNS which may affect sensation, movement, gland, organ function
What are large myelinated axons responsible for
motor and sensory info
- light touch, movement, vibration, proprioception
What are small myelinated axons responsible for
autonomic fibers and sensory axons
- light touch, pain, temp
What are small unmyelinated axons responsible for
autonomic
- sensory and enhancement of pain and temp
Describe the inputs of the cervical, brachial, lumbar, sacral, and coccygeal plexuses
What are some of the most common causes of peripheral neuropathy
- DM
- Alcoholism
- carpal tunnel syndrome
- post herpetic neuralgia
- spinal radiculopathy
What is the most common pattern of peripheral neuropathy
generalized sensorimotor polyneuropathy with axonal degeneration - diabetes
What are the 3 types of peripheral neuropathies
- mononeuropathies: 1 nerve)
- polyneuropathies: multiple symmetric nerves
- mononeuritis multiplex: multiple non-symmetric nerves
What are the 4 causes of peripheral neuropathies
- traumatic
- systemic
- infectious/autoimmune
- hereditary
Describe some systemic causes of PN
- vitamin deficiencies
- medications
- toxins/poisons
- systemic diseases
- cancer
What are some of the major autoimmune causes of PN
- DM
- RA
- Guillan Barre
- Sjogren’s
- Celiac
- SLE
- necrotizing vasculitis
What is one of the major hereditary causes of PN
Charcot Marie Tooth Disease
- flaw in gene responsible for making neurons/myelin sheath
- extreme weakness, wasting of muscles in lower legs
- pes cavus foot deformity
Describe the pathophys of Wallerian Degeneration
- axon degenerates distal to focal
- often caused by carpal tunnel or direct trauma
- can regenerate
Describe segmental demyelination
segments of myelin coating break down but axon is spared (Charcot Marie, GBS, SLE, RA, Sjogren’s)
Describe Axonal Degeneration
- most common neuronal response to injury (DM, toxins, meds, nutritional deficiencies)