S10L1 - Nerve Injuries Of The Lower Limb Flashcards
What is a neuron?
An electrically excitable cell that receives, processes and transmits information through chemical and electrical signals.
Describe the structure of a neurone
Cell body - contains the cell nucleus
Dendrites - thin structures arising from the cell body, usually where the neurone receives signals
Axon - specialised cellular projection, arises at the axon hillock. Transmits signal down the axon.
What is a nerve?
An enclosed bundle of axons within fascicles and their supporting cells (Schwann cells) in the peripheral nervous system
What is the endoneurium?
A connective tissue Layer that surrounds an individual axons and its supportive cells within a nerve. Consists of an inner sleeve of glycocalyx and a mesh of collagen.
The endoneurium contains endoneurial fluid.
What is the function of the endoneurium?
Functions similar to the blood-Brain barrier, prevents certain molecules from crossing from the blood into the endoneurial fluid. Contains endoneurial fluid which is similar to the cerebrospinal fluid.
How can nerve injury or irritation be detected?
During nerve irritation and injury, the amount of endoneurial fluid increases in the endoneurium. This oedema can be detected with an MRI scan.
What is a nerve fascicle?
Many Axons, each individually surrounded by endoneurium, bundled together forms a fascicle.
Fascicles are wrapped in a layer of connective tissue called a perineurium.
What is the vasa nervorum?
The nerves own blood vessels within the epineurium
