Glossary
Use this glossary to help define text within the information provided.  The bold text is the basic definition of the term.  More detailed information is provided afterwards.

Abduction 
Movement away from the midline.  For fingers, it is movement away from the midline of the middle digit.  For the thumb, it is movement perpendicular to, and away from, the plane of the palm.  For the hand, at the wrist, it is radial deviation of the hand, which is away from the midline of the body in the anatomical position.  For the arm, at the shoulder joint, abduction moves the elbow in the frontal plane away from the midline of the body.

Active Range of Motion  
Range of motion that a person has unassisted by someone else.  The extent of movement of an anatomical segment at a joint when the movement is produced by the voluntary effort of the subject being tested.

Active Myofascial Trigger Point
A myofascial trigger point that causes a clinical pain complaint.  It is always tender, prevents full lengthening of the muscle, weakens the muscle, refers a patient-recognized pain on direct compression, mediates a local twitch response of muscle fibers when adequately stimulated, and, when compressed within the patient’s pain tolerance, produces referred motor phenomena and often autonomic phenomena, generally in its pain reference zone, and causes tenderness in the pain reference zone.   To be distinguished from a latent myofascial trigger point.

Acute
Refers to time.  Of recent onset (hours or days)

Adduction
Movement toward the midline.  For fingers, it is movement toward the midline of the middle digit.  For the thumb, it is movement perpendicular to, and toward, the plane of the palm.  For the hand, it is ulnar deviation at the wrist.  Fort he arm, at the shoulder joint, it is movement of the elbow toward the midline of the body, movement in the frontal plane from the abducted position of the arm. 

Anatomical Position
The erect position of the body with the face forward, each arm at the side of the body, forearms supinated so that the palms of the hands are facing forward, fingers in extension, feet together with the toes directed forward.  The terms posterior, anterior, lateral, medial, superior, inferior, etc. are applied with the body in this position.

Anterior
Front side of the body.

Arm
In anatomical terms the arm refers to the area between the shoulder and elbow in the upper extremity.

Attachment Trigger Point (ATrP)
A trigger point at the musculotendinous junction and/or at the osseous attachment of the muscle that identifies the enthesopathy caused by unrelieved tension characteristic of the taut band that is produced by a central trigger point.

Bruxism
Clenching of the teeth, resulting in rubbing, gritting, or grinding together of the teeth, usually during sleep.

Caudad
Away from the head, toward the tail; usually synonymous with inferior; opposite of cephalad.

Central Myofascial Trigger Point (CTrP)
A myofascial trigger point that is closely associated with dysfunctional endplates and is located near the center of muscle fibers.

Chronic
Long lasting (weeks, months or years), but NOT necessarily irreversible.  Symptoms may be mild or severe.

Composite Pain Pattern
Total referred pain pattern of two or more closely adjacent muscles.  No distinction is made among the referred pain patterns of the individual muscles.

Deep
Farther from the surface; opposite of superficial.

Distal
Father from the trunk or point of origin; opposite of proximal.

Dysesthesia
An unpleasant abnormal sensation, whether spontaneous or evoked.

Enthesopathy
A disease process at musculotendinous junctions and/or where tendons and ligaments attach into bones or joint capsules.  It is characterized by local tenderness and may, in time, develop into enthesitis.

Extension
In general, straightening of hinge joints.  In the upper limb, it is movement in the posterior direction in a sagittal plane.  In the case of the thumb, it is movement in the radial direction in the plane of the palm.

Flexion
In general, bending of hinge joints.  In the upper limb, it is movement in the anterior direction in a sagittal plane.  In the case of the thumb, it is movement in the ulnar direction in the plane of the palm.

Functional Unit
A group of agonist and antagonist muscles that function together as a unit because they share common spinal-reflex responses.  The agonist muscles may act in series or in parallel.  Previously identified as a Myotatic Unit.

Hyperesthesia
Increased sensitivity to stimulation, excluding the special senses.

Hyperpathia
A painful syndrome characterized by abnormally painful reaction to a stimulus, especially a repetitive stimulus (both threshold and response are increased).

Hyperalgesia
An increased pain response to a stimulus that is normally painful (stimulus and response are in the same mode).

Hypoalgesia
Diminished pain in response to a normally painful stimulus.

Inferior
Toward the soles of the feet; synonymous with caudal in the trunk; opposite of superior.

Ischemic Compression
Now revised and identified as Trigger Point Pressure Release.

Jump Sign
A general pain response of the patient, who winces, may cry out, and may withdraw in response to pressure applied on a trigger point.  This term has been used erroneously to describe the local twitch response of muscle fibers to trigger-point stimulation.

Key Myofascial Trigger Point
A trigger point responsible for activating one or more satellite trigger points.  Clinically, a key trigger point is identified when inactivation of that trigger point also inactivates the satellite trigger point.

Latent Myofascial Trigger Point
A myofascial trigger point that is clinically quiescent with respect to spontaneous pain; it is painful only when palpated.  A latent trigger point may have all the other clinical characteristics of an active trigger point and always has a taut band that increases muscle tension and restricts range of motion.

Lateral
Farther from the midsagittal plane of the body or from the midline of a structure; opposite of medial.

Lateral Rotation (External Rotation, Rotation Outward)
Rotation of the anterior surface of the limb away from the midline of the body.

Local Twitch Response
A transient contraction of a group of tense muscle fibers (taut band) that traverse a trigger point.  The contraction of the fibers is in response to stimulation (usually by snapping palpation or needling) of the same trigger point, or sometimes of a nearby trigger point.  Sometimes the local twitch response has been erroneously called a jump sign.

Medial
Closer to the midsagittal plane of the body or the midline of a structure; opposite of lateral.

Medial Rotation (Internal Rotation, Rotation Inward)
Rotation of the anterior surface of the limb toward the midline of the body.

Motor Endplate
Soleplate ending where a terminal branch of the axon of a motor neuron makes synaptic contact with a striated muscle fiber.

Myofascial Pain Dysfunction Syndrome
A controversial, largely outmoded term that has been considered to mean a syndrome largely of muscular origin, a complex psychophysiological phenomenon, or syndrome primarily due to disturbed occlusal mechanics.

Myofascial Pain Syndrome (MPS)
The sensory, motor, and autonomic symptoms caused by myofascial trigger points.

Myofascial Trigger Point (MTrP)
Clinical Definition – A hyperirritable spot in skeletal muscle that is associated with a hypersensitive palpable nodule in a taut band.  The spot is painful on compression and can give rise to characteristic referred pain, referred tenderness, motor dysfunction, and autonomic phenomena.

Paradoxical (Abnormal) Respiration
(Chest breathing) Simultaneous expansion of the chest and contraction of abdominal muscles that pulls the abdomen inward during inhalation.  To be distinguished from coordinated (normal) respiration.

Passive Range of Motion
The range of motion a body has when assisted by another person.  The extent of movement (usually tested in a given plane) of an anatomical segment at a joint when movement is produced by an outside force without voluntary assistance or resistance by the test subject.  The subject must relax the muscles crossing the joint.

Posterior
Toward the back of the body (dorsal); opposite of anterior.

Prone
Lying face downward; opposite of supine.

Proximal
Closer to the trunk or point of origin; opposite of distal.

Referred Autonomic Phenomena
Vasoconstriction (blanching), coldness, sweating, pilootor response, ptosis, and/or hypersecretion that occur in a region separate from the trigger point causing these phenomena.  The phenomena usually appear in the same general area to which that trigger point refers pain.

Referred (Trigger Point) Pain
Pain that arises in a trigger point, but is felt at a distance, often entirely remote from its source.  The pattern of referred pain is reproducibly related to its site of origin.  The distribution of referred trigger-point pain rarely coincides entirely with the distribution of a peripheral nerve or dermatomal segment.

Referred (Trigger Point) Phenomena
Sensory and motor phenomena such as pain, tenderness, increased motor unit activity (spasm), vasoconstriction, vasodilatation, and hypersecretion caused by a trigger point, which usually occur at a distance from the trigger point.

Scoliosis
(Curved spine) Lateral curvature of the spine such as that when the spine is viewed from the posterior (back) it resembles the shape of a “S” or a “C”.

Spasm
Increased tension with or without shortening of a muscle due to nonvoluntary motor nerve activity.  Spasm is identified by motor unit potentials that cannot be terminated by voluntary relaxation.  To be distinguished from contracture.

Spillover Pain Zone (Area)
The region where some, but not all, patients experience referred pain beyond the essential pain zone, due to greater hyperirritability of a trigger point.  The spillover zone is indicated by red stippling in the pain pattern figures.  To be distinguished from an essential referred pain zone that is solid red.

Strain
Tissue and psychological reaction to prolonged stress.

Stretch
Any procedure that elongates the muscle fibersWith trigger points, the goal of the procedure is to release the increased muscle tension by elongating the shortened sarcomeres of contraction knots.

Stress
1. A physical or psychological overload that produces a tissue or psychological reaction.  2. The resisting force set up in a body as a result of an externally applied force.  3. A force that tends to produce distortion.

Superficial
Closer to the surface; opposite of deep.

Superior
Toward the vertex (top) of the head; usually synonymous with cephalad; opposite of inferior.

Supination
A movement of the forearm that positions the palm anteriorly when the body is in the anatomical position.

Supine
Lying face upward; opposite of prone.

Synergistic Muscles
Muscles that reinforce or complement each other when they contract.

Taut Band
The group of tense muscle fibers extending from a trigger point to the muscle attachments.  The tension of the fibers is caused by contraction knots that are located in the region of the trigger point.  Reflex contraction of the fibers in this band produces the local twitch response.

Trigger Point Pressure Release
Application of slowly increasing, nonpainful pressure over a trigger point until a barrier of tissue resistance is encountered.  Contact is then maintained until a barrier of tissue resistance is encountered.  Contact is then maintained until the tissue barrier releases, and pressure is increased to reach a new barrier to eliminate the trigger point tension and tenderness.  This term replaces Ischemic Compression.

Zone of Reference
The specific region of the body at a distance from a trigger point, where phenomena (sensory, motor, and/or autonomic) caused by the trigger point are observed.


Reference :

Simons DG, Travell JG, Simons LS.  Myofascial Pain and Dysfunction : The Trigger Point Manual, vol 1, 2nd  Ed. Baltimore: Williams and Wilkins, 1999.

Glossary