Clinical signs and treatment of lesion of the brachial plexus

1. Big picture

The brachial plexus is the nerve network that supplies the upper limb. A lesion of the plexus causes a combination of motor weakness, sensory loss, reflex changes, pain, and autonomic signs that does not fit one single root or one single peripheral nerve.

For the exam, the key task is to decide:

1. Is the lesion root, plexus, or peripheral nerve?
2. Is it an upper plexus, lower plexus, or whole plexus lesion?
3. Is it traumatic, compressive, inflammatory, neoplastic, radiation-induced, or iatrogenic?
4. Does it need urgent surgery, tumor workup, or conservative rehabilitation?

The classic exam syndromes are:

Upper brachial plexus lesion, C5–C6 = Erb-Duchenne palsy Lower brachial plexus lesion, C8–T1 = Klumpke palsy

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