Brachial neuritis has two major clinical symptoms: pain and muscle weakness from atrophy. Brachial neuritis usually is characterized by the acute onset of excruciating unilateral shoulder pain, followed by flaccid paralysis of shoulder and parascapular muscles several days later. Brachial neuritis can vary greatly in presentation and nerve involvement 2. Brachial neuritis is believed to be a multifocal, immune-mediated inflammatory process that involves the peripheral nerves. Most lesions are axonal, however those caused by demyelination usually carry a better prognosis. Motor axons are mainly affected.
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Although several mechanisms account for brachial plexus injuries, the most common is nerve compression or stretch. Infants, in particular, may suffer brachial plexus injuries during delivery and these present with typical patterns of weakness, depending on which portion of the brachial plexus is involved.
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. For example, musculocutaneous nerve damage weakens elbow flexors , median nerve damage causes proximal forearm pain, and paralysis of the ulnar nerve causes weak grip and finger numbness. In less severe cases, these injuries limit use of these limbs and cause pain.
The arm cannot be raised from the side; all power of flexion of the elbow is lost, as is also supination of the forearm". The epineurium of the nerve is contiguous with the dura mater , providing extra support to the nerve. Brachial plexus lesions typically result from excessive stretching; from rupture injury where the nerve is torn but not at the spinal cord; or from avulsion injuries , where the nerve is torn from its attachment at the spinal cord.
A bony fragment, pseudoaneurysm, hematoma , or callus formation of fractured clavcile can also put pressure on the injured nerve, disrupting innervation of the muscles. A trauma directly on the shoulder and neck region can crush the brachial plexus between the clavicle and the first rib.
These injuries can be located in front of or behind the clavicle , nerve disruptions, or root avulsions from the spinal cord. These injuries are diagnosed based on clinical exams, axon reflex testing, and electrophysiological testing. These types of injuries are most common in young adult males. Injury from a direct blow to the lateral side of the scapula is also possible.
The severity of nerve injuries may vary from a mild stretch to the nerve root tearing away from the spinal cord avulsion. The subsequent paralysis affects, principally, the intrinsic muscles of the hand and the flexors of the wrist and fingers". Mechanism[ edit ] Injury to the brachial plexus can happen in numerous environments.
These may include contact sports, motor vehicle accidents, and birth. The two mechanisms that can occur are traction and heavy impact.
The nerves of the brachial plexus are damaged due to the forced pull by the widening of the shoulder and neck. This is a closer look at the traction mechanism at the cervical spine. The arrowed red line represents the stretch of the nerves. Depending on the force, lesions may occur. This image shows the anterior view of the five brachial plexus nerves on the human arm. Axillary, Median, Musculocutaneous, Radial, Ulnar.
The brachial plexus is made up of spinal nerves that are part of the peripheral nervous system. It includes sensory and motor nerves that innervate the upper limbs. The brachial plexus includes the last four cervical nerves C5-C8 and the 1st thoracic nerve T1. Each of those nerves splits into smaller trunks, divisions, and cords. The lateral cord includes the musculocutaneous nerve and lateral branch of the median nerve. The medial cord includes the medial branch of the median nerve and the ulnar nerve.
The posterior cord includes the axillary nerve and radial nerve. There are two types of traction: downward traction and upward traction. In downward traction there is tension of the arm which forces the angle of the neck and shoulder to become broader. This tension is forced and can cause lesions of the upper roots and trunk of the nerves of the brachial plexus.
Humeral fractures and shoulder dislocations can also cause this type of injury with high energy injuries. In peripheral mechanism, traction is transmitted to the rootlet, however dura mater will be torn with the rootlet intact because the dura is less elastic when compared to the rootlet.
Pseudomeningocele can be shown on cervical myelography. On the other hand, through central mechanism, the head and neck is pushed along with the spinal roots of the brachial plexus to the opposite site of the body, leading to direct nerve root injury but the dura sheath remains intact. In this case, anterior roots are more prone than posterior roots for avulsion, thus the C8 and T1 nerve roots are more prone to injury.
Root avulsion injury can be further divided based on the location of the lesion: pre- and postganglionic lesions. In a preganglionic lesion, the sensory fibre remain attached to the cell body of the sensory ganglion, thus there is no wallerian degeneration of the sensory fibre, thus sensory action potential can still be detected at the distal end of the spinal nerve. However, those who get this type of lesion has sensory loss over the affected nerve roots.
In this case, surgical repair of the lesion is not possible because the proximal nerve tissue is too short for stitching to be possible. For postganglionic lesions, the cell body of the sensory ganglion is detached from the spinal nerve, leading to wallerian degeneration of the sensory fibre. Thus, no action potential detected at the distal end of spinal nerve.
However, surgical repair is possible because proximal nerve tissue has enough length for stitching. Depending on the severity of the impact, lesions can occur at all nerves in the brachial plexus. The location of impact also affects the severity of the injury and depending on the location the nerves of the brachial plexus may be ruptured or avulsed.
When passing through between the clavicle and first rib, the brachial plexus maybe crushed in the costoclavicular space. This is usually due to direct trauma to the shoulder or neck region as a result of motorvehicular accidents, occupational injuries or sports injuries. The brachial plexus may also be compressed by surrounding damaged structures such as bone fragments or callus from the clavicular fracture, and haematoma or pseudoaneurysm from vascular injury.
Cervical rib, prominent transverse process, and congenital fibrous bands can also compress the brachial plexus and causes thoracic outlet syndrome. During this process, the brachial plexus can receive damage resulting in injury.
The incidence of this happening at birth is 1 in Nerves should be evaluated under an operative microscope, with or without intraoperative electrical studies e.
Operative evaluation of the rootlets within the spinal canal and intraforaminal portion of the spinal roots proximal to the dorsal root ganglia e. 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. These examinations are painful, highly user-dependent and lack normal values so cannot be relied upon. Classification[ edit ] The severity of brachial plexus injury is determined by the type of nerve damage.
Most systems attempt to correlate the degree of injury with symptoms, pathology and prognosis. It involves an interruption of the nerve conduction without loss of continuity of the axon. Recovery takes place without wallerian degeneration.
Not only the axon, but the encapsulating connective tissue lose their continuity. The most extreme degree of neurotmesis is transsection, although most neurotmetic injuries do not produce gross loss of continuity of the nerve but rather, internal disruption of the nerve architecture sufficient to involve perineurium and endoneurium as well as axons and their covering.
It requires surgery, with unpredictable recovery. With fifth degree injuries, the nerve is completely divided. Some brachial plexus injuries may heal without treatment. 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. However, in more serious brachial plexus injuries surgical interventions can be used.
Function can be restored by nerve repairs, nerve replacements, and surgery to remove tumors causing the injury. On top of promoting a lifetime process of physical healing, it is important to not overlook the psychological well-being of a patient. This is due to the possibility of depression or complications with head injuries. Improvements occur slowly and the rehabilitation process can take up to many years. Many factors should be considered when estimating recovery time, such as initial diagnosis of the injury, severity of the injury, and type of treatments used.
One of the main goals of rehabilitation is to prevent muscle atrophy until the nerves regain function. Electrical stimulation is an effective treatment to help patients reach this fundamental goal. 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 done on a daily basis to improve or maintain range of motion.
Stretching is important in order to rehabilitate since it increases the blood flow to the injury as well as facilitates nerves in functioning properly.
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. Patients also exhibited a greater variability in the postural oscillation, evaluated by the directional stability index.
The results alert the clinical community about the necessity to prevent and treat secondary effects of this condition. Type of delivery also affects the risk of BPI. Prognosis[ edit ] The site and type of brachial plexus injury determine the prognosis.
Avulsion and rupture injuries require timely surgical intervention for any chance of recovery.
Brachial plexus injury
Address e-mail to moc. Abstract Objective: To present the unique case of a collegiate wrestler with C7 neurologic symptoms due to T1—T2 disc herniation. Background: A year-old male collegiate wrestler injured his neck in a wrestling tournament match and experienced pain, weakness, and numbness in his left upper extremity. He completed that match and 1 additional match that day with mild symptoms.
Current concepts of the treatment of adult brachial plexus injuries. J Hand Surg Am. Guideline recommendations summarized in the body of a DynaMed topic are provided with the recommendation grading system used in the original guideline s , and allow users to quickly see where guidelines agree and where guidelines differ from each other and from the current evidence. Strong recommendations are used when, based on the available evidence, clinicians without conflicts of interest consistently have a high degree of confidence that the desirable consequences health benefits, decreased costs and burdens outweigh the undesirable consequences harms, costs, burdens.