Musculoskeletal Growth Injury and Repair – Peripheral Nerve Injuries Flashcards
What are the two units of a nerve…worded that weird but you know it
Motor and sensory units
What are the motor units (efferent) and where are they located?
Anterior horn cells found in grey matter of spinal cord
What are the sensory units (afferent) and where are they located?
Cell bodies in the posterior root ganglia i.e. outside of the spinal cord
Nerve fibres joint to form motor and sensory roots. Are the sensory roots anterior or posterior and ventral or dorsal?
Posterior/dorsal roots
Nerve fibres joint to form motor and sensory roots. Are the motor roots anterior or posterior and ventral or dorsal?
Anterior/ventral roots
What surrounds larger peripheral nerve fibres?
Myelin sheath which provides insulation
What are axons coated with?
Endoneurium - type of CT
What are axons grouped together to form?
A fascicle
What are fascicles grouped together to form?
Nerve
What type of CT covers nerves?
Epineurium
What cells surround neurones?
Schwann cells
RECAP- which type of fibres travel the quickest?
A alpha fibres
->these are the biggest fibres
RECAP- which type of fibres travel the slowest?
C fibres
->these are the smaller fibres
Which fibres transmit dull, aching or burning pain and temperature sensation?
C fibres
Which fibres transmit sharp pain and light touch?
A delta fibres
Which fibres transmit touch, pressure, vibration and join position sensory axons?
A beta fibres
Give some examples of direct trauma injuries.
Blow or laceration
Give some examples of indirect trauma injuries.
Avulsion or traction
List some common conditions caused by compression of a nerve.
Carpal tunnel syndrome
Sciatica
Morton’s neuroma
Which nerve gets compressed in carpal tunnel syndrome?
Median nerve
Which nerves get compressed in sciatica?
Spinal roots by IV discs
What nerve get compressed in Morton’s neuroma?
Digital nerve in 2nd or 3rd web space of forefoot
Neurapraxia?
Mild nerve injury in which nerve has been stretched or bruised
Causes conduction block and local ischaemia and demyelination
What is prognosis of neurapraxia?
Good as reversible, settles after weeks or month