[1][2][3] Brachial plexus injuries can occur as a result of shoulder trauma (e.g. dislocation[4]), tumours, or inflammation, or obstetric.

The brachial plexus may also be injured by direct violence or gunshot wounds, by violent traction on the arm, or by efforts at reducing a dislocation of the shoulder joint".

The most severe form of injury is nerve root avulsion, which usually accompanies high-velocity impacts that commonly occur during motor-vehicle collisions or bicycle accidents.

[2] Based on the location of the nerve damage, brachial plexus injuries can affect part of or the entire arm.

[10] The cardinal signs of brachial plexus injury then, are weakness in the arm, diminished reflexes, and corresponding sensory deficits.

A bony fragment, pseudoaneurysm, hematoma, or callus formation of fractured clavicle can also put pressure on the injured nerve, disrupting innervation of the muscles.

[15][16] Brachial plexus injuries require quick treatment in order for the patient to make a full functional recovery (Tung, 2003).

The brachial plexus may also be injured by direct violence or gunshot wounds, by violent traction on the arm, or by efforts at reducing a dislocation of the shoulder joint".

This tension is forced and can cause lesions of the upper roots and trunk of the nerves of the brachial plexus.

The brachial plexus may also be compressed by surrounding damaged structures such as bone fragments or callus from the clavicular fracture, and hematoma or pseudoaneurysm from vascular injury.

Cervical rib, prominent transverse process, and congenital fibrous bands can also compress the brachial plexus and cause thoracic outlet syndrome.

[21] The most accurate test for diagnosing a brachial plexus injury is operative exploration of the potentially injured segments from the spinal roots to end-organs.

Nerves should be evaluated under an operative microscope, with or without intraoperative electrical studies (e.g. bipolar stimulation, SEPs or MEPs) to supplement.

MRI aids in the assessment of the injuries and is used to provide information on the portion of the plexus which cannot be operatively explored (the rootlets and roots).

In addition, assessment of the cervical cord, post-traumatic changes in soft tissues and associated injuries (e.g. fractures, cuff tears, etc.)

Many infants improve or recover within 6 months, but those that do not, have a very poor outlook and will need further surgery to try to compensate for the nerve deficits.

Gentle range of motion exercises performed by parents, accompanied by repeated examinations by a physician, may be all that is necessary for patients with strong indicators of recovery.

[36] Another crucial factor to note is that psychological problems can hinder the rehabilitation process due to a lack of motivation from the patient.

On top of promoting a lifetime process of physical healing, it is important to not overlook the psychological well-being of a patient.

Exercises that involve shoulder extension, flexion, elevation, depression, abduction and adduction facilitate healing by engaging the nerves in the damaged sites as well as improve muscle function.

Stretching is important in order to rehabilitate since it increases the blood flow to the injury as well as facilitates nerves in functioning properly.

[39] A study has also shown that a sensory-motor deficit in the upper limbs after a brachial plexus injury can affect the corporal balance in the vertical positioning.

Examined patients had a lower score in the Berg Balance Scale, a greater difficulty in maintaining in the unipodal stance during one minute and leaned the body weight distribution to the side affected by the lesion.

The results alert the clinical community about the necessity to prevent and treat secondary effects of this condition.

[40] In studies about the effectiveness of additional effect of modified constraint induced movement therapy (MCIMT), it was found that MCIMT helped improved the range of motion, shoulder function and it has the potential to promote functional gains for children with BPBI.

[42] People who have accidents with riding motorcycles and snowmobiles have higher risks of getting a BPI[46] and with ihg-injury injuries such as motorcycle accidents, root avulsion from the spinal cord is the most common pattern of injury (~72% prevalence of at least 1 root avulsion)[27] which requires surgery to reanimate the arm.

Equally, reconstruction of elbow flexion in patients with pan-plexus injuries should be performed as soon as possible, because delays lead to worse motor outcomes.

[4] For milder injuries involving buildup of scar tissue and for neurapraxia, the potential for improvement varies, but there is a fair prognosis for spontaneous recovery, with a 90–100% return of function.