Muscle Tone and Manual Muscle Testing - PowerPoint Presentation

Slide1

Muscle Tone and Manual Muscle Testing

PHT 1261C Tests and Measurements

Dr. KaneSlide2

Definitions

Tone

Factors affecting tone

Postural Tone

Hypertonia

Hypotonia

Dystonia

Spasticity – velocity dependent

Clasp knife response

UMN syndrome

Clonus

Babinski Sign

Rigidity

Lead pipe

CogwheelSlide3

Definitions - continued

Hypotonia

– flaccidity

LMN syndrome

Spinal Shock/Cerebral Shock

Dystonia

Focal vs. segmental vs. posturing

Decorticate Rigidity

Decerebrate

Rigidity

OpisthotonusSlide4

Variations in Tone

Volitional Effort and movement

Stress and anxiety

Position and interaction of tonic reflexes

Medications

General Health

Environmental temperatures

State of CNS arousal or alertness

Urinary bladder status

Fever/infection

Metabolic or Electrolyte imbalancesSlide5

Examination of Tone

Initial Observation of resting posture & palpation

Common posturing – see Table 8.1 page 235

Palpation – consistency, firmness & turgor

Passive Motion Testing

Responsiveness of muscles to stretch

Vary speed for spasticity and clonus

Grading Scale

0 = no response (flaccidity)

1+ = decreased response (

hypotonia

)

2+ = Normal response

3+ = exaggerated response (mild to moderate hypertonia)

4+ = sustained response (severe hypertonia)

Active Motion Testing/Special Tests

Pendulum test

MyotonometerSlide6

Spastic Hypertonia – Modified Ashworth Scale

Gold standard subjective 5 point ordinal scale

Interrater

&

intrarater

reliability is good

Problems:

Inability to detect small changes

Limited to extremity testing only

Grades

0 = no increase in muscle tone

1 = slight increase in muscle tone; catch & release

1+ = slight increase in tome with catch & minimal resistance through rest of range

2 = marked increase in tone through most of ROM

3 – considerable increase in tone; passive motion difficult

4 = affected parts rigid in flexion or extensionSlide7

Deep Tendon Reflexes

Table 8.3 page 237 O’Sullivan

Grading Scale

0 = no response

1+ = present but depressed, low normal

2+ = Average, normal

3+ = Increased, brisker than average; possibly but not necessarily normal

4+ = very brisk, hyperactive with clonus; abnormal

Increased with UMN lesions; decreased with LMN

Reinforcement maneuversSlide8

Manual Muscle Testing

Palmer Chapter 2

Not applicable for strength testing in patients who lack voluntary or active control of muscular tension (e.g. CNS disorders)

Not appropriate for spasticity

May get inaccurate results due to gravity and activation of stretch reflex

Reliability – ½ grade

intertester

is acceptable

Follow proper procedures

Give clear instructions

Demonstrate and explain

Improved with dynamometry Slide9

Manual Muscle Testing - continued

Validity

Palpate muscle

Proper stabilization

Prevent substitution muscles or patterns

Not functionalSlide10

MMT Uses

1. Establish a basis for muscle re-

ed

and exercise;

Develop plan of care

Show progress

Shows effectiveness of treatment

Additional information before muscle transfer surgery

2. Determines how functional a patient can be.

3. Determines a pt.'s needs for supportive apparatus –

orthoses

, splints, assistive devices

4. Helps determine a diagnosis.

5. Determines pt.'s prognosisSlide11

Factors that Contribute to Effectiveness of Muscle Contraction

Length of muscle when activated

Active insufficiency

Type of contraction

Eccentric > Isometric > Concentrically

Muscle Fiber Types

Type I slow twitch – fatigue resistant

Type II fast twitch – fatigue rapidly

Must consider speed of contraction & resistance applied

Type II – require less resistance to reach “normal” grade

Speed of contraction

Increased speed = increased tension ECCENTRIC

Increased speed = decreased tension CONCENTRICSlide12

Anatomical Factors that affect Muscle Contraction

Number of motor units per muscle

Functional excursion

Cross sectional Area

Line of pull of muscle fibers

Number of joints crossed

Sensory receptors

Attachments to bone & relationship to joint axis

Age of pt.

Sex of pt.Slide13

Evaluating Skeletal Muscle Strength

Anatomical, physiological, & biomechanical knowledge of skeletal muscle positions and stabilization

Elimination of substitution motions

Skill in palpation & application of resistance

Careful direction for each movement that is easily understood by the patient

Adherence to a standard method of grading muscle strength

Experience testing many individuals with normal muscle strength & varying degrees of weaknessSlide14

Factors to Consider in MMT

Weight of limb or distal segment with minimal effect of gravity (GM)

Weight of limb plus the effects of gravity (AG)

Weight of limb plus gravity plus manual resistanceSlide15

Factors Affecting Grading of MMT

Amount of manual resistance applied (opposite torque exerted by muscle)

Ability of muscle to move through complete ROM

Evidence of presence or absence of muscle contraction by palpation & observation

Gravity and manual resistance

GM – muscle contracts parallel to gravitational force

AG – muscle contract against the downward gravitational force

Grades are dependent on: age, sex, body build, occupation, etc.Slide16

Factors affecting MMT Results

Fatigue

Joint ROM limitations

Range grade/strength grade (-20 degrees/4 (good)

Pain

Subjectivity

Positions –AG/GM

Range

Palpation

Resistance –break or make method

Stabilization

Provides support

Prevents substitution motions

Substitution

Recording measurements Slide17

Procedure For Specific MMT

Position in AG position & stabilize – see page 31

Expose body part & drape appropriately

Explain the test and demonstrate to patient

Determine available ROM

PROM or AROM; test range; possibly goniometry

Align body part to direction of muscle fibers

Stabilize proximal segment

Have patient move distal segment through test ROM or hold at end range of motion

Observe and palpate muscle belly

Apply resistance – end range or through range

Record grade & date & initial; document in SOAP