Brachial Plexus Center

  • Glossary of Terms

    The Brachial Plexus Center at Cincinnati Children’s Hospital Medical Center provides this glossary to help you understand words you may hear during your child’s evaluation and treatment.

  • Show All

    + A

    Abduction
    Movement of the limbs away from the body, such as lifting the arm out to the side.

    Adduction
    Movement of the limbs toward the body, such as bringing the arm close to the body from the side.

    Anterior
    Toward the front.

    Atrophy
    A wasting away or decrease in the size of a cell, tissue, organ or body part. Atrophy occurs when muscles are not used due to lack of nerve function.

    Avulsion
    Tearing away. The nerve root being torn out of the spinal cord is the most severe type of nerve injury. An eyelid droop suggests a very severe avulsion of the lower brachial plexus, known as Horner’s syndrome.

    Axilla
    The underarm area.

    + B

    Biceps
    A muscle with two heads or origins. This muscle is used to flex the elbow.

    Bilateral
    Having two sides or pertaining to both sides.

    Brachial
    Relating to the arm.

    Brachial plexus
    A network of lower cervical and upper dorsal spinal nerves that control movement of the arm, forearm and hand.

    Brachial plexus injury
    Also known as Erb’s palsy (upper trunk injury), Klumpke’s palsy (lower trunk injury), Erb-Duchenne palsy, obstetrical brachial plexus palsy (OBPI), trauma-based brachial plexus injury (TBPI) and neonatal brachial plexus injury.

    Breech delivery
    Birth or delivery of the fetus that takes place when the infant’s buttocks or feet come out first.

    + C

    Cervical
    Pertaining to the neck or to the neck of any structure.

    Cervical plexus
    A network of nerve fibers originating in the upper four cervical spinal cord segments.

    Clavicle
    Also called the collarbone, the clavicle joins with the shoulder on one end and the sternum on the other.

    Contracture
    A permanent shortening (as of muscle tendons or scar tissue that produces deformity or distortion).

    Contusion
    A bruise or injury that does not puncture the skin.

    + D

    Deltoid
    A large triangular muscle that covers the shoulder joint. This muscle is used to raise the arm.

    Diaphragm
    The thin muscle below the lungs and heart that separates the chest from the abdomen.

    Distal
    Farthest from any point of reference. A part of the body farthest away from the center of the body.

    Dorsal
    Describing the back or upper surface of a body part.

    Dystocia
    A difficult labor or delivery.

    + E

    EMG (electromyogram)
    A test where a small needle is inserted into muscle to record electrical activity inside the muscle.

    Erb’s palsy
    A type of brachial plexus injury that often presents with the child’s arm straight and wrist fully bent (waiter’s tip). The child may have good hand function but not full movement of the arm. Nerves C5, C6 and sometimes C7 are involved.

    Extension
    The movement of two elements of any jointed body part are directed away from each other (straightened).

    Extensor
    A muscle that extends or straightens a body part, such as a finger or an arm.

    + F

    Fasciculations
    Muscle contractions that appear as uncontrollable muscle twitching or tics. They usually indicate a neurological disorder and may be common with a brachial plexus injury.

    Fibrous tissue
    Although most connective tissue has fibrillar elements, the term usually refers to tissue laid down at a wound site, forming a scar.

    Flaccid
    Weak, lacking firmness, muscle tone and resilience.

    Flexion
    Moving a joint inward to bring it closer to the body (bend).

    Flexor
    A muscle that bends or flexes any body part, such as the arm or hand.

    + G

    Gestational age
    Fetal age of a newborn, calculated from conception until birth.

    + H

    Horner’s syndrome
    A nerve condition that includes a drooping eyelid (ptosis), constricted pupil, sunken eyeball (enophthalmos) and lack of sweating on one side of the face. Horner’s syndrome is caused by a lesion in the cervical sympathetic nerve trunk in the neck.

    + I

    Innervation
    The nervous excitation necessary for the maintenance of the life and functions of the various organs including muscles.

    Intercostal
    Situated between the ribs.

    + K

    Klumpke’s palsy
    A rare injury of the lower brachial plexus (usually following breech delivery where the arm is above the baby’s head), where the child’s hand muscles and finger flexors are paralyzed.

    + L

    Luxation
    Complete dislocation of a joint. (Subluxation is partial dislocation of a joint.)

    + M

    Medial
    The side of the body or body part that is nearer to the middle or center of the body.

    Motor
    A muscle, nerve or center that effects or produces movement.

    MRI (magnetic resonance imaging) scan
    An MRI uses a powerful magnet, radio waves and a computer to acquire pictures of the inside of your child’s body. MRI can be used to take small section pictures of just about any body part. Tour the MRI at Outpatient Mason.

    Multidisciplinary team
    A team of medical professionals that work together to support the patient. A multidisciplinary team for brachial plexus injuries would include a rehabilitation physician, orthopaedic surgeon, plastic surgeon and therapists.

    Musculocutaneous
    Pertaining both to muscles and skin.

    + N

    Narakas Classification
    In 1986, A.O. Narakas (Algimantas Otonas Narakas, 1927-1993) published a classification system of neonatal brachial plexus palsy based on the clinical course of children during the first eight weeks of life.

    Neurolysis
    Surgical removal or part of a neuroma.

    Neuroma
    A benign tumor composed of nerve cells, or scar tissue that forms when there is nerve damage.

    Neuroma excision
    When a neuroma is large, it must be removed. The nerve is then reattached either with end-to-end techniques or with nerve grafts.

    Nerve grafting
    When the gap between nerve ends is so large that it is not possible to have a tension-free repair using the end-to-end techniques or with nerve grafts.

    Neurotization
    This is used generally in those cases where there is an avulsion. Donor nerves are used for the repair. The parts of the roots still attached to the spinal cord can be used as donors for avulsed nerves.

    Neurapraxia
    The nerve has been stretched and damaged but not torn.

    + O

    Occupational therapist
    A healthcare professional who provides services designed to restore self-care, work and leisure skills to patients who have specific performance incapacities or deficits that reduce their abilities to cope with the tasks of everyday living.

    Orthopaedic surgeon
    A medically qualified doctor who specializes in surgery of the bones.

    + P

    Paralyze
    To affect or strike with paralysis or palsy.

    Passive
    Neither spontaneous nor active, not produced by active efforts.

    Pectoralis muscles
    Muscular tissues attached to the front of the chest wall and extending to the upper arms. These are located under the breast.

    Peripheral nerves
    The nerves outside of the brain and spinal cord, including the automatic, cranial and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons.

    Peripheral neuropathy
    Injury to the nerves that supply sensation to the arms and legs.

    Phrenic nerves
    The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.

    Physiatrist
    A physician specializing in physical medicine and rehabilitation. Physiatrists help restore optimal function to people with injuries to the muscles, bones, tissues and nervous system.

    Physical therapist
    A trained rehabilitation professional who promotes optimal health function and independence by teaching exercises and other physical activities to aid in rehabilitation and maximize physical ability with less pain.

    Plastic and reconstructive surgeon
    A medically qualified specialist who specializes in surgery of the face, head, neck and nerve repairs.

    Plexus
    A network or tangle. Plexus is a general term for a network of lymphatic vessels, nerves or veins.

    Posterior
    Situated in back or in the back part of or affecting the back or dorsal surface of the body.

    Proximal
    Closest from any point of reference. A part of the body closet to the center of the body.

    + R

    Range of motion (ROM)
    The range through which a joint can be moved, usually its range of flexion and extension. Active range of motion (AROM) is the active movement of the muscle. Passive range of motion (PROM) is the motion range of a joint through manual assistance.

    Rupture
    Torn nerve or tissue.

    + S

    Spontaneous
    An action or process that happens by internal impulse or energy. A spontaneous action occurs without force.

    Subscapularis muscle action
    Rotates medially. Subscapularis muscle action helps in adduction, abduction, flexion and extension.

    Supine
    Lying on the back.

    + T

    Tactile
    Able to feel or sense things by touch.

    Teres minor muscle
    Upper dorsal axillary border of scapula. The teres minor muscle is used to rotate your child’s arm laterally and adduct it.

    Thoracic
    Pertaining to or affecting the chest.

    Torticollis
    A contracted state of the cervical muscles, producing twisting of the neck and an unnatural position of the head.

    Trapezius muscle action
    Rotates scapula to raise point of shoulder. It abducts the scapula: the upper part raises the scapula, the lower part lowers and pulls the scapula down. The upper part also draws the head to the same side and turns face to opposite site. The two sides together draw the head back.

    Triceps muscle action
    Extends and adducts the forearm.