peripheral nerve lesions

Last reviewed 01/2018

Peripheral nerve mononeuropathies are usually due to a single local lesion. The motor distribution is constant so that the level of the lesion can be ascertained from the muscles affected. The cutaneous distribution is fairly specific but often shows some variability and overlap.

An entrapment neuropathy occurs when a peripheral nerve is damaged by passage through a tight space. It may be precipitated by swelling of the soft tissue as in acromegaly, myxoedema, and pregnancy; for example, entrapment of the median nerve in carpal tunnel syndrome. Occasionally, such conditions show a familial tendency.

A compression neuropathy occurs when sustained pressure is applied to a peripheral nerve which lies between skin and bone, relatively unprotected by soft tissue; for example, "saturday night palsy" due to compression of the radial nerve against the humerus.