this session by simon strauss myofascial pain. part a myofascial pain. part b pain assessment tools....

This Session by Simon Strauss

• Myofascial Pain. Part A

• Myofascial Pain. Part B

• Pain Assessment Tools. Part C

Definitions and Language of Pain

Allodynia- 1. A lower than normal pain threshold.

2. A clinical situation where pain results from a

stimulus which should normally be painless.

3. Pain upon palpation at less than 4kg/cm2 or

less at a site, which does not cause pain at the same anatomic site in normal individuals.

Dysesthesia- Unpleasant sensations ranging from numbness

to ‘pins and needles’.

Definitions and Language of Pain

Hyperalgesia: A greater than normal response to a

stimulus expected to cause pain in a

normal individual.

Fibromyalgia: Chronic widespread Allodynia.

Nociception: The neurochemical process by which pain

signals are transmitted from the periphery

to the CNS and perceived by the individual

Definitions and Language of Myofascial Pain

Myofascial Trigger Points (MTrPs) :

May be active or latent

An active Myofascial trigger point

is a focus of hyper-irritability

in a muscle or its fascia

that causes the patient pain.


An active Myofascial trigger point

causes pain and tenderness at rest or with motion that

stretches or loads the muscle.

It prevents full lengthening of the muscle, as well as

fatigue and decreased strength.

Pressure on an active MTrP induces / reproduces some

of the patient’s pain complaint and is recognised by the

patient as being some or all of his or her pain.


A Latent Myofascial Trigger Point: does not cause

pain during normal activities.

It is locally tender, but causes pain only when palpated.

It also refers pain on pressure.

It can be associated with a weakened shortened more easily

fatigued muscle.

A Palpable / Taut Band: is a group of muscle fibres that

is associated with MTrPs and is identifiable by its rope-like

consistency.


Twitch response: a transient contraction of part of the

involved muscle in response to needling or ‘snapping

palpation’

Jump Sign: A general pain response of the patient, who

may wince, vocalise or ‘jump’ in response to pressure on a

MTrP.

Involved muscle: A muscle that contains one or more

MTrPs

Myofascial Pain Syndromes

Can be thought of

as Pain Syndromes

that are caused by and are maintained by one or more active

Trigger Points and their associated reflexes

Myofascial Pain Syndromes

TheTrigger Point

is the Pain Generator

Myofascial Pain Syndromes PrevalenceUnselected and Control Groups

Danish study of 1504 people, aged 30 - 60, 37% of males

and 65% of females had localised myofascial pain.

100 male and 100 female airforce personnel (Av. Age 19)

45% of males and 54% females had focal neck muscle

tenderness ( latent trigger points).

269 female student nurses. 45% had TrPs in masseter,

35% had TrPs in trapezious.

28% had myofascial pain at the time of examination.

Myofascial Pain Syndromes Prevalence

Unselected and Control Groups Lumbogluteal muscles: Assessment of

100 asymptomatic control subjects.

Revealed latent TrPs in

45% of Quadratus Lumborum,

41% of Gluteous Medius,

11% of Gluteous Minimus,

5% of Piriformis.


Anecdotal evidence suggests that

Ballerinas, Swimmers, Runners and

indeed any group of athletes that uses a

group of muscles in a prolonged or

repeatedly forceful manner are likely to have

latent trigger points and therefore can be

“toppled” into a Myofascial pain state.

Myofascial Pain Syndromes Prevalence Patient Groups

Community pain medical center.

96 Patients studied by a neurologist:

93% had at least part of their pain

caused by myofascial TrPs

and in

74% of the patients myofascial TrPs were considered to be the primary source of Pain.


Patient Groups Comprehensive pain center

283 consecutive admissions to a comprehensive pain center:

The diagnosis made independently by a Neurosurgeon and a

Physiatrist based on physical examination as described by

Travell and Simons assigned a primary organic diagnosis of

myofascial pain in 85% of the cases.


Percentage of Patients with another diagnosis who also

had Myofascial TrPs contributing to their pain problems

Diagnosis Number MyofascialTrPs % with

Source

CervicogenicHeadache

80 100% Lin et al

ReflexsympatheticDystrophy

84 82% Lin et al

Fibromyalgia 19 100% Finestone et al

Myofascial Trigger Points Clinical Features

History of spontaneous pain associated

with acute overload or chronic overuse of

the muscle.The mildest symptoms are caused by latent TrPs which

cause no pain but cause some degree of functional

disability.

More severe involvement results in pain related to the

position or movement of the muscle.

The most severe level involves pain at rest.


Palpable Band.A cord like band of fibres is present in the involved

muscle.

This can be difficult to identify when there are overlying

muscles or thick subcutaneous tissue.

INJURY


Spot Tenderness

A very tender small spot which is found in a Taut

Band.

The sensitivity of this spot (TrPs) can be increased by

increasing the tension on the muscle fibres of the taut

band.


Jump Sign

Pressure on the tender spot causes the patient to

physically react to the precipitated pain by exclaiming or

moving.

Ah-Shi - Oh yes!

This reaction indicates the level of tenderness but is

also dependent on the pressure exerted by the examiner.


Pain Recognition

Digital pressure on or needling of the tender spot induces / reproduces some of the patient’s pain

complaint and is recognised by the patient as being

some or all of his or her pain.

Ah-Shi - Oh yes!

This finding by definition identifies an active trigger point.

This replication of the patient’s pain may require

sustained pressure (5 - 60 seconds) on the TrP.


Twitch Response

Is a transient contraction of the muscle fibres of the

taut band containing the trigger point.

The twitch response can be elicited by “snapping”

palpation of the trigger point.

Or more commonly by precise needling of the trigger

point.


Elicited referred pain and or tenderness

An active MTrP refers pain in a pattern characteristic of

that muscle -Usually to a site distant to the TrP.

85% of TrPs project distally.

[The area of the referred pain is often tender and may

contain satellite trigger points.]

Latent TrPs also refer pain on pressure but usually require

more pressure to do so.


Restricted Range of Movement.

Full stretching of the affected muscle is often involuntarily

restricted by pain.

Inactivation of the associated MTrP releases the taut band

that is (? reflexly) restricting the muscle.


Muscle Weakness

The patient is unable to demonstrate normal muscle

strength on static testing of the affected side as compared to

the contra-lateral non-affected side.

The involved muscle is also more easily fatigued.

Myofascial Trigger PointsPostulated Explanations of Clinical Features

Clinical Feature Possible Explanation

Palpable Band Continuos abnormal release of Calciumfrom sarcoplasmic reticulum

Spot Tenderness Sensitisation of nociceptors in vicinity ofmotor endplate

Jump Sign Severity of Trigger Point tenderness

Pain Recognition Aggravation of the Trigger point

Twitch Response Spinal reflex activation of motor units

Referred Pain and Tenderness Excitation of ‘sleeping nociceptors’

Restricted Range of Movement Increase release of acetylcholine inneuromuscular junctions due tomechanical stress with related increase ofsensitising substances

Muscle Weakness Reflex inhibition of involved muscle

Myofascial Trigger PointsPathogenic Factors

Acute overload

Overwork - Fatigue (Including postural stress)

Chilling

Gross Trauma

Other Trigger Points

Emotional distress

Joint or nerve damage

Visceral disturbance

Chart outlining the natural course of Myofascial pain caused by Trigger Points

Taut Band

Latent TrPs

Active TrPs

SpontaneousRecovery

Persistencewithout

progression

PerpetuatingFactors

Additional TrPs& Chronicity

STRESS

PathogenicFactors

this session by simon strauss myofascial pain. part a myofascial pain. part b pain assessment tools....

Documents

patient pain

pain results

pain generator slide

language of pain allodynia

language of pain hyperalgesia

general pain response

normal pain threshold

simon strauss myofascial