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A brachial plexus injury (BPI), also known as brachial plexus lesion, is an injury to the
brachial plexus The brachial plexus is a network () of nerves formed by the anterior rami of the lower four cervical nerves and first thoracic nerve ( C5, C6, C7, C8, and T1). This plexus extends from the spinal cord, through the cervicoaxillary canal in t ...
, the network of nerves that conducts signals from the
spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...
to the
shoulder The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder mak ...
, arm and hand. These nerves originate in the fifth, sixth, seventh and eighth cervical (C5–C8), and first thoracic (T1) spinal nerves, and innervate the muscles and skin of the chest, shoulder, arm and hand. Brachial plexus injuries can occur as a result of shoulder trauma, tumours, or inflammation, or
obstetric Obstetrics is the field of study concentrated on pregnancy, childbirth and the postpartum period. As a medical specialty, obstetrics is combined with gynecology under the discipline known as obstetrics and gynecology (OB/GYN), which is a surg ...
. Obstetric injuries may occur from mechanical injury involving
shoulder dystocia Shoulder dystocia is when, after vaginal delivery of the head, the baby's anterior shoulder gets caught above the mother's pubic bone. Signs include retraction of the baby's head back into the vagina, known as "turtle sign". Complications for th ...
during difficult
childbirth Childbirth, also known as labour and delivery, is the ending of pregnancy where one or more babies exits the internal environment of the mother via vaginal delivery or caesarean section. In 2019, there were about 140.11 million births glob ...
, with a prevalence of 1 in 1000 births. "The brachial plexus may be injured by falls from a height on to the side of the head and shoulder, whereby the nerves of the plexus are violently stretched. 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 rare Parsonage–Turner syndrome causes brachial plexus inflammation without obvious injury, but with nevertheless disabling symptoms.


Signs and symptoms

Signs and symptoms may include a limp or paralyzed arm, lack of muscle control in the arm, hand, or wrist, and lack of feeling or sensation in the arm or hand. Although several mechanisms account for brachial plexus injuries, the most common is nerve compression or stretch. Infants, in particular, may experience 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.


Disabilities

Based on the location of the nerve damage, brachial plexus injuries can affect part of or the entire arm. For example, musculocutaneous nerve damage weakens elbow flexors, median nerve damage causes proximal
forearm The forearm is the region of the upper limb between the elbow and the wrist. The term forearm is used in anatomy to distinguish it from the arm, a word which is most often used to describe the entire appendage of the upper limb, but which in ...
pain, and paralysis of the ulnar nerve causes weak grip and finger numbness. In some cases, these injuries can cause total and irreversible paralysis. In less severe cases, these injuries limit use of these limbs and cause pain. The cardinal signs of brachial plexus injury then, are
weakness Weakness is a symptom of a number of different conditions. The causes are many and can be divided into conditions that have true or perceived muscle weakness. True muscle weakness is a primary symptom of a variety of skeletal muscle diseases, i ...
in the arm, diminished reflexes, and corresponding sensory deficits. #
Erb's palsy Erb's palsy is a paralysis of the arm caused by injury to the upper group of the arm's main nerves, specifically the severing of the upper trunk C5–C6 nerves. These form part of the brachial plexus, comprising the ventral rami of spinal ner ...
. "The position of the limb, under such conditions, is characteristic: the arm hangs by the side and is rotated medially; the forearm is extended and pronated. The arm cannot be raised from the side; all power of flexion of the elbow is lost, as is also supination of the forearm". # In
Klumpke's paralysis Klumpke's paralysis is a variety of partial palsy of the lower roots of the brachial plexus. p.1046 The brachial plexus is a network of spinal nerves that originates in the back of the neck, extends through the axilla (armpit), and gives rise to ne ...
, a form of paralysis involving the muscles of the forearm and hand,Glanze et al. (1990) p.667 a characteristic sign is the ''clawed hand'', due to loss of function of the ulnar nerve and the intrinsic muscles of the hand it supplies.


Causes

In most cases, the nerve roots are stretched or torn from their origin, since the meningeal covering of a nerve root is thinner than the sheath enclosing the nerve. The
epineurium The epineurium is the outermost layer of dense irregular connective tissue surrounding a peripheral nerve. It usually surrounds multiple nerve fascicles as well as blood vessels which supply the nerve. Smaller branches of these blood vessels pe ...
of the nerve is contiguous with the
dura mater In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. ...
, 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 In medicine, an avulsion is an injury in which a body structure is torn off by either trauma or surgery (from the Latin ''avellere'', meaning "to tear off"). The term most commonly refers to a surface trauma where all layers of the skin have been ...
, where the nerve is torn from its attachment at the spinal cord. A bony fragment, pseudoaneurysm, hematoma, or
callus A callus is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on the feet and hands, but they may o ...
formation of fractured clavicle 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. Although injuries can occur at any time, many brachial plexus injuries happen during birth: the baby's shoulders may become impacted during the birth process causing the brachial plexus nerves to stretch or tear. Obstetric injuries may occur from mechanical injury involving
shoulder dystocia Shoulder dystocia is when, after vaginal delivery of the head, the baby's anterior shoulder gets caught above the mother's pubic bone. Signs include retraction of the baby's head back into the vagina, known as "turtle sign". Complications for th ...
during difficult childbirth, the most common of which result from injurious stretching of the child's brachial plexus during birth, most often during vaginal birth, but occasionally Caesarean section. The excessive stretch results in incomplete sensory and/or motor function of the injured nerve. Injuries to the brachial plexus result from excessive stretching or tearing of the C5-T1
nerve fibers A nerve is an enclosed, cable-like bundle of nerve fibers (called axons) in the peripheral nervous system. A nerve transmits electrical impulses. It is the basic unit of the peripheral nervous system. A nerve provides a common pathway for the e ...
. These injuries can be located in front of or behind the
clavicle The clavicle, or collarbone, is a slender, S-shaped long bone approximately 6 inches (15 cm) long that serves as a strut between the shoulder blade and the sternum (breastbone). There are two clavicles, one on the left and one on the r ...
, nerve disruptions, or root avulsions from the
spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the sp ...
. These injuries are diagnosed based on clinical exams,
axon reflex The axon reflex (or the flare response) is the response stimulated by peripheral nerves of the body that travels away from the nerve cell body and branches to stimulate target organs. Reflexes are single reactions that respond to a stimulus makin ...
testing, and electrophysiological testing. Brachial plexus injuries require quick treatment in order for the patient to make a full functional recovery (Tung, 2003). These types of injuries are most common in young adult males.
Trauma Trauma most often refers to: * Major trauma, in physical medicine, severe physical injury caused by an external source * Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event *Traumatic i ...
tic brachial plexus injuries may arise from several causes, including sports, high-velocity motor vehicle accidents, especially in
motorcyclists Motorcycling is the act of riding a motorcycle. For some people, motorcycling may be the only affordable form of individual motorized transportation, and small- displacement motorcycles are the most common motor vehicle in the most populous c ...
, but also all-terrain-vehicle (ATV) and other accidents. Injury from a direct blow to the lateral side of the
scapula The scapula (plural scapulae or scapulas), also known as the shoulder blade, is the bone that connects the humerus (upper arm bone) with the clavicle (collar bone). Like their connected bones, the scapulae are paired, with each scapula on eith ...
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 brachial plexus may be injured by falls from a height on to the side of the head and shoulder, whereby the nerves of the plexus are violently stretched… 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". Brachial plexus lesions can be divided into three types: # An upper brachial plexus lesion, which occurs from excessive lateral neck flexion away from the shoulder. Most commonly, improper use of forceps during delivery or falling on the neck at an angle causes upper plexus lesions leading to
Erb's palsy Erb's palsy is a paralysis of the arm caused by injury to the upper group of the arm's main nerves, specifically the severing of the upper trunk C5–C6 nerves. These form part of the brachial plexus, comprising the ventral rami of spinal ner ...
. This type of injury produces a very characteristic sign called ''Waiter's tip deformity'' due to loss of the lateral rotators of the shoulder, arm flexors, and hand extensor muscles. # Less frequently, the whole brachial plexus lesion occurs; # most infrequently, sudden upward pulling on an abducted arm (as when someone breaks a fall by grasping a tree branch) produces a lower brachial plexus lesion, in which the eighth cervical ( C8) and first thoracic (T1) nerves are injured "either before or after they have joined to form the lower trunk. The subsequent paralysis affects, principally, the intrinsic muscles of the hand and the flexors of the wrist and fingers". This results in a form of paralysis known as
Klumpke's paralysis Klumpke's paralysis is a variety of partial palsy of the lower roots of the brachial plexus. p.1046 The brachial plexus is a network of spinal nerves that originates in the back of the neck, extends through the axilla (armpit), and gives rise to ne ...
. Backpack palsy is caused by much use of a heavy backpack whose pack-straps chronically press on the brachial plexus.


Mechanism

Injury to the brachial plexus can happen in numerous environments. These may include contact sports, motor vehicle accidents, and birth. Although these are but a common few events, there is one of two mechanisms of injury that remain constant during the point of injury. The two mechanisms that can occur are traction and heavy
impact Impact may refer to: * Impact (mechanics), a high force or shock (mechanics) over a short time period * Impact, Texas, a town in Taylor County, Texas, US Science and technology * Impact crater, a meteor crater caused by an impact event * Impac ...
.


Anatomy

The
brachial plexus The brachial plexus is a network () of nerves formed by the anterior rami of the lower four cervical nerves and first thoracic nerve ( C5, C6, C7, C8, and T1). This plexus extends from the spinal cord, through the cervicoaxillary canal in t ...
is made up of spinal nerves that are part of the
peripheral nervous system The peripheral nervous system (PNS) is one of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system (CNS). The PNS consists of nerves and ganglia, which lie outside the brain ...
. It includes sensory and motor nerves that innervate the upper limbs. The brachial plexus includes the last four
cervical nerves A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into the ...
(C5-C8) and the 1st
thoracic nerve A spinal nerve is a mixed nerve, which carries motor, sensory, and autonomic signals between the spinal cord and the body. In the human body there are 31 pairs of spinal nerves, one on each side of the vertebral column. These are grouped into th ...
(T1). Each of those nerves splits into smaller trunks, divisions, and cords. The lateral cord includes the
musculocutaneous nerve The musculocutaneous nerve arises from the lateral cord of the brachial plexus, opposite the lower border of the pectoralis major, its fibers being derived from C5, C6 and C7. Structure The musculocutaneous nerve arises from the lateral cor ...
and lateral branch of the
median nerve The median nerve is a nerve in humans and other animals in the upper limb. It is one of the five main nerves originating from the brachial plexus. The median nerve originates from the lateral and medial cords of the brachial plexus, and has cont ...
. The medial cord includes the medial branch of the median nerve and the ulnar nerve. The posterior cord includes the
axillary nerve The axillary nerve or the circumflex nerve is a nerve of the human body, that originates from the brachial plexus ( upper trunk, posterior division, posterior cord) at the level of the axilla (armpit) and carries nerve fibers from C5 and C6. Th ...
and radial nerve.


Traction

Traction occurs from severe movement and causes a pull or
tension Tension may refer to: Science * Psychological stress * Tension (physics), a force related to the stretching of an object (the opposite of compression) * Tension (geology), a stress which stretches rocks in two opposite directions * Voltage or el ...
among the nerves. 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 The human shoulder is made up of three bones: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (upper arm bone) as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder mak ...
to become broader. This tension is forced and can cause
lesions A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classifi ...
of the upper roots and trunk of the nerves of the brachial plexus. Motorcycle accidents and sports injuries usually cause this type of injury to brachial plexus. Upward traction also results in the broadening of the scapulo-humoral angle but this time the nerves of T1 and C8 are torn away. Humeral fractures and shoulder dislocations can also cause this type of injury with high energy injuries. Root avulsion or nerve rupture may occur during severe trauma, inappropriate surgical positioning, or inappropriate use of surgical retractors. There are two mechanisms for root avulsion injury: peripheral and central mechanism. In peripheral mechanism, traction is transmitted to the rootlet, however
dura mater In neuroanatomy, dura mater is a thick membrane made of dense irregular connective tissue that surrounds the brain and spinal cord. It is the outermost of the three layers of membrane called the meninges that protect the central nervous system. ...
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 Myelography is a type of radiographic examination that uses a contrast medium to detect pathology of the spinal cord, including the location of a spinal cord injury, cysts, and tumors. Historically the procedure involved the injection of a radioc ...
. 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 In the autonomic nervous system, fibers from the CNS to the ganglion are known as preganglionic fibers. All preganglionic fibers, whether they are in the sympathetic division or in the parasympathetic division, are cholinergic (that is, these ...
lesion, the sensory fibre remain attached to the cell body of the sensory ganglion, thus there is no
wallerian degeneration Wallerian degeneration is an active process of degeneration that results when a nerve fiber is cut or crushed and the part of the axon distal to the injury (i.e. farther from the neuron's cell body) degenerates. A related process of dying back o ...
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 have 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 In the autonomic nervous system, fibers from the ganglion to the effector organ are called postganglionic fibers. Neurotransmitters The neurotransmitters of postganglionic fibers differ: * In the parasympathetic division, neurons are ''chol ...
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.


Impact

Heavy impact to the shoulder is the second common mechanism to causing injury to the brachial plexus. Depending on the severity of the impact,
lesions A lesion is any damage or abnormal change in the tissue of an organism, usually caused by disease or trauma. ''Lesion'' is derived from the Latin "injury". Lesions may occur in plants as well as animals. Types There is no designated classifi ...
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 may be 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 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. During the delivery of a baby, the shoulder of the baby may graze against the
pelvic bone The hip bone (os coxae, innominate bone, pelvic bone or coxal bone) is a large flat bone, constricted in the center and expanded above and below. In some vertebrates (including humans before puberty) it is composed of three parts: the ilium, isch ...
of the mother. During this process, the brachial plexus can receive damage resulting in injury. The incidence of this happening at birth is 1 in 1000. This is very low compared to the other identified brachial plexus injuries.


Diagnosis

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. Operative evaluation of the rootlets within the spinal canal and intraforaminal portion of the spinal roots proximal to the dorsal root ganglia (e.g. via hemilamiinectomy or otherwise) is difficult and rarely clinically justifiable, so in the context of an apparently in-continuity root, preoperative imaging studies are the only method of evaluating this section of nerve. The best non-invasive test for BPI is magnetic resonance imaging (MRI). 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.) may be appreciated. Although superior to nerve conduction studies, ultrasound and other tests, conventional MRI has a poor specificity (72%) meaning that the false-positive rate is high and surgeons can't rely upon the test to guide treatment. Consequently, the future of peripheral nerve MR imaging (including imaging brachial plexus injuries) is likely to be based on diffusion-weighted imaging, such as diffusion tensor techniques, which are of significant potential clinical utility and can enable the production of easily interpreted 3D reconstructions of the spinal cord and brachial plexus such a
this
Several weeks/months after BPI, EMG examination can provide additional information about whether the muscle is denervated. These examinations are painful, highly user-dependent and lack normal values so cannot be relied upon.


Classification

The severity of brachial plexus injury is determined by the type of nerve damage. There are several different classification systems for grading the severity of nerve and brachial plexus injuries. Most systems attempt to correlate the degree of injury with symptoms, pathology and prognosis.
Seddon's classification Classification of peripheral nerve injury assists in prognosis and determination of treatment strategy. Classification of nerve injury was described by Seddon in 1943 and by Sunderland in 1951. The lowest degree of nerve injury in which the nerve r ...
, devised in 1943, continues to be used, and is based on three main types of nerve fiber injury, and whether there is continuity of the nerve. #
Neurapraxia Neurapraxia is a disorder of the peripheral nervous system in which there is a temporary loss of motor and sensory function due to blockage of nerve conduction, usually lasting an average of six to eight weeks before full recovery. Neurapraxia is ...
: The mildest form of nerve injury. It involves an interruption of the nerve conduction without loss of continuity of the
axon An axon (from Greek ἄξων ''áxōn'', axis), or nerve fiber (or nerve fibre: see spelling differences), is a long, slender projection of a nerve cell, or neuron, in vertebrates, that typically conducts electrical impulses known as action p ...
. Recovery takes place without
wallerian degeneration Wallerian degeneration is an active process of degeneration that results when a nerve fiber is cut or crushed and the part of the axon distal to the injury (i.e. farther from the neuron's cell body) degenerates. A related process of dying back o ...
.Glanze, W.D., Anderson, K.N., & Anderson, L.E (1990), p.805 #
Axonotmesis Axonotmesis is an injury to the peripheral nerve of one of the extremities of the body. The axons and their myelin sheath are damaged in this kind of injury, but the endoneurium, perineurium and epineurium remain intact. Motor and sensory functions ...
: Involves axonal degeneration, with loss of the relative continuity of the axon and its covering of myelin, but preservation of the connective tissue framework of the nerve (the encapsulating tissue, the
epineurium The epineurium is the outermost layer of dense irregular connective tissue surrounding a peripheral nerve. It usually surrounds multiple nerve fascicles as well as blood vessels which supply the nerve. Smaller branches of these blood vessels pe ...
and
perineurium The perineurium is a protective sheath that surrounds a nerve fascicle. This bundles together axons targeting the same anatomical location. The perineurium is composed from fibroblasts. In the peripheral nervous system, the myelin sheath of each ...
, are preserved).Glanze, W.D., Anderson, K.N., & Anderson, L.E (1990), p.117 #
Neurotmesis Neurotmesis (in Greek tmesis signifies "to cut") is part of Seddon's classification scheme used to classify nerve damage. It is the most serious nerve injury in the scheme. In this type of injury, both the nerve and the nerve sheath are disrupted. ...
: The most severe form of nerve injury, in which the nerve is completely disrupted by contusion, traction or laceration. 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 The endoneurium (also called endoneurial channel, endoneurial sheath, endoneurial tube, or Henle's sheath) is a layer of delicate connective tissue around the myelin sheath of each myelinated nerve fiber in the peripheral nervous system. Its com ...
as well as axons and their covering. It requires surgery, with unpredictable recovery.Glanze, W.D., Anderson, K.N., & Anderson, L.E (1990), p.810 A more recent and commonly used system described by the late Sir Sydney Sunderland, divides nerve injuries into five degrees: first degree or neurapraxia, following on from Seddon, in which the insulation around the nerve called myelin is damaged but the nerve itself is spared, and second through fifth degree, which denotes increasing severity of injury. With fifth degree injuries, the nerve is completely divided.


Treatment

Treatment for brachial plexus injuries includes orthosis/splinting, occupational or physical therapy and, in some cases, surgery. 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. The ability to bend the elbow (biceps function) by the third month of life is considered an indicator of probable recovery, with additional upward movement of the wrist, as well as straightening of thumb and fingers an even stronger indicator of excellent spontaneous improvement. 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. The exercises mentioned above can be done to help rehabilitate from mild cases of the injury. 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 A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
causing the injury. 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. This is due to the possibility of depression or complications with head injuries.


Rehabilitation

There are many treatments to facilitate the process of recovery in people who have brachial plexus 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.Rirch R. Greenwood R, Barnes M, McMillan T, Ward C: Management of brachial plexus injuries. Handbook of neurological rehabilitation. Second ed. New York, NY: Psychology Press; 2003. p663-94 Some forms of treatment include nerve grafts, medication, surgical decompression, nerve transfer, physical therapy, and occupational therapy.


Therapy

Physical and occupational therapy is important when dealing with a brachial plexus injuries. One of the main goals of rehabilitation is to prevent muscle atrophy until the nerves regain function.
Electrical stimulation Functional electrical stimulation (FES) is a technique that uses low-energy electrical pulses to artificially generate body movements in individuals who have been paralyzed due to injury to the central nervous system. More specifically, FES can ...
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 Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately flexed or stretched in order to improve the muscle's felt elasticity and achieve comfortable muscle tone. The result is a feeling ...
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. 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 The Berg Balance Scale (or BBS) is a widely used clinical test of a person's static and dynamic balance abilities, named after Katherine Berg, one of the developers. For functional balance tests, the BBS is generally considered to be the gold sta ...
, 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.


Epidemiology

Brachial plexus injury is found in both children and adults, but there is a difference between children and adults with BPI.


Adults

The prevalence of brachial plexus injuries in North American adults in the 1900s was about 1.2%. BPI is most commonly found in young healthy adults, from ages 14 to 63 years old, with 50% of patients between 19 and 34 years old. 89% of BPI patients are male. The rate of brachial plexus injury has been increasing.


Children

OBPP, also known as obstetrical brachial plexus palsy, occurs primarily in young children at a rate of 0.38 to 1.56 per 1000 live births depending on the type of care and the average birth weight of infants in different regions of the world. For example, a study in the United States showed and incidence of OBPP of about 1.51 cases per 1000 live births, in a
Canadian Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of ...
study, the incidence was between 0.5 and 3 injuries per 1000 live births, a Dutch study reported an incidence of 4.6 per 1000 live births. The risk of BPI at birth is highest for infants weighing more than 4.5 kg at birth born to
diabetic Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...
women. Type of delivery also affects the risk of BPI. Brachial plexus injury risks for newborns are increased with gained birth weight, birth delivery where a vacuum is assisted, and not being able to handle
glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...
.


Traumatic injuries

BPI has shown to occur in 44% to 70% of traumatic
injuries An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or o ...
, such as motorcycle
accidents An accident is an unintended, normally unwanted event that was not directly caused by humans. The term ''accident'' implies that nobody should be blamed, but the event may have been caused by unrecognized or unaddressed risks. Most researche ...
, sporting activities, or workplace accidents. With 22% being motorcycle
injuries An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or o ...
and about 4.2% having plexus damage. People who have
accidents An accident is an unintended, normally unwanted event that was not directly caused by humans. The term ''accident'' implies that nobody should be blamed, but the event may have been caused by unrecognized or unaddressed risks. Most researche ...
with riding motorcycles and snowmobiles have higher risks of getting a BPI 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) which requires surgery to reanimate the arm.


Prognosis

The site and type of brachial plexus injury determine the prognosis. Avulsion and rupture injuries require timely surgical intervention for any chance of recovery. 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.


References


External links

{{Neurotrauma Neurotrauma Injuries of neck