Peripheral Nerve Injuries Flashcards
What is occurring in the nerve during Neurapraxia?
The nerve is stretched/bruised
What is occurring in the nerve during Axonotmesis?
Endoneurium is intact but there is a disruption of axons - more severe injury
Occurs when the nerve is stretched or crushed/direct blow
What is Neurotmesis?
Complete nerve division.
Laceration/Avulsion.
No recovery unless repaired.
What are the 2 main classes of nerve injury?
Open and closed
What is meant by a closed nerve injury and what is an example and prognosis?
Nerve injuries that affect continuity (Neuropraxias and Axonotmesis).
Spontaneous recovery is possible - surgery indicated after 3 months if no recovery.
Examples:
- Brachial plexus injury
- Radial nerve humeral fracture.
What is meant by an open nerve injury and what is an example and prognosis?
Nerve dissection (Neurometic injuries i.e. knives/glass).
Treated with early surgery.
Define Wallerian degeneration
An active process of degeneration that results when a nerve fibre is cut or crushed - axon distal to injury degenerates.
What are some clinical features of nerve injury?
Sensory:
- Dysethesia (Disordered sensation)
Motor:
- Paresis (weakness) or paralysis
- Dry skin
Reflexes:
-Diminished reflexes/Absent
Define Tinel’s sign
A way to detect irritated/repairing nerves.
Percussing over the nerve to illicit a pins and needles sensation in the distribution of the nerve.
Strength in an upper motor neuron lesion will be increased or decreased?
Decreased
Strength in a lower motor neuron lesion will be increased or decreased?
Decreased
Tone in an upper motor neuron lesion will be increased or decreased?
Increased
Tone in a lower motor neuron lesion will be increased or decreased?
Decreased
Deep tendon reflexes will be increased or decreased in an UMN lesion?
Increased
Deep tendon reflexes will be increased or decreased in a LMN lesion?
Decreased
