Article Text
Statistics from Altmetric.com
Focal peripheral neuropathies are not at the fashionable end of the neurological street. However they are important, as they are very common, sometimes disabling, and often treatable. They can also be a source of confusion when they occur in patients with other neurological diseases.
This article will not go over the detailed clinical features of the many focal peripheral neuropathies that occur, though these are briefly summarised in tables 1 and 2. These can be found in many neurology textbooks, though I would particularly recommend two short texts that include clear, copiously referenced descriptions of all focal neuropathies.1,2 Aids to the examination of the peripheral nervous system3 is a useful aide memoir, which you should carry in your bag.
- In this window
- In a new window
- In this window
- In a new window
This brief review will explore the general approach to focal neuropathies, including issues relating to management and clinical presentation.
GENERAL APPROACH
The management of focal peripheral neuropathies is based on certain general principles with a relatively limited backing from clinical trials. These principles relate to understanding the:
-
types of peripheral nerve injury
-
mechanisms of injury
-
ability and limitations of neurophysiology to aid diagnosis
-
peripheral nerve anatomy.
Types of peripheral nerve injury
Regardless of the cause, nerve injury can be classified according to severity. This directs management and acts as guide to rate of recovery. The types of injury are:
-
a neuropraxia, where there is focal or segmental demyelination with preservation of the axon and recovery in 2–12 weeks
-
an axonotmesis, where the axon is divided but the epineurium remains intact and regrows at 1 mm per day from the site of injury
-
a neurotmesis, where the nerve is divided and no longer in continuity with no recovery.
At the site of focal nerve injury there may …
Footnotes
-
↵* Square wrist sign present when anteroposterior dimension of wrist divided by mediolateral dimension, measured at the distal wrist crease, is greater than 0.7.