The brachial plexus corresponds to the origin of the upper limb’s nerves.
The brachial plexus runs from the spine to the axillary fossa. It originates from 5 nerve roots C5, C6, C7, C8 and D1, which form 3 primary trunks in the neck and then 3 secondary trunks (cords) in the axilla before emerging as the upper limb’s main 6 nerves: suprascapular nerve, axillary nerve, musculocutaneous nerve, radial nerve, median nerve and ulnar nerve.
The vulnerability of the brachial plexus resides mainly in its original roots, which are located in the neck. The most frequent cause of lesion is a violent fall on the shoulder tip (or top of the shoulder), often in motorbike accidents. Such cases are known as supraclavicular brachial plexus palsy.
In some direct injuries, the lesion can be located in the axilla (knife wound, bullet wound, complicated fracture of the clavicle).Such cases are called infraclavicular brachial plexus paralysis.
Wherever the injury is located (supraclavicular or infraclavicular), treatment follows three main principles:
- surgery is not always necessary, for some types of palsy, spontaneous recovery is possible in the months following the injury;
- when no recovery is made within a year of the injury, direct nerve surgery, known as nerve grafting or neurotisation, is possible;
- when no recovery is made and a year or more has elapsed since the injury, only musculotendinoustransfer and/or arthrodesis (joint fusion) surgery is possible.
Recovery depends on various factors:
It depends on the patient’s age, on the time elapsed since the injury, on whether paralysis is complete or partial and on the type of nerve lesion (nerve torn or stretched).
Recovery often spreads over an 18-month period.
The younger the patient, the better the recovery, so the treatment of plexic injuries is not the same for children and teenagers and for adults. Likewise, beyond 60 years old, palliative musculotendinous transfer and joint fusion surgery is preferred when considering direct nerve repair surgery.
The older the injury, the longer and harder post-operative recovery will be.
Besides, when the 5 roots are completely damaged, healing is not as good as when damage is partial.
When the nerve is completely severed, which is referred to as radicular avulsion, recovery is markedly poorer.