Muscle Performance Flashcards
Why might muscle strength testing be different with an infant or child than with an adult?
*Musculoskeletal system development
*Age norms?
*Ability to generate consistent force
*Cooperation, ability to follow directions, attention span
Are muscle power and endurance measurable in infants or children?
- For endurance: use functional tests
- For power: only when child large enough to use isokinetic system
Methods of muscle strength testings
- Functional Strength Testing
- Manual Muscle Testing
- Hand Held Dynamometer
- Isokinetics
Functional movement assessment for infants:
- Body, arm, leg movements against gravity
- Reflexes and postural responses (ATNR or MORO reflex in 3 mo old or lateral head righting reaction)
Functional movement assessment tasks for toddlers/preschoolers
- Tip toes
- Get up from floor
- Jump
- Stand on one foot
Standardized pediatric examination
BOT-2
Physical fitness test
- Flexed arm hang
- Push up
- Sit up/curl up
Pediatric modifications to MMT
- Observation/ movement activation/ palpation method
- Standardized MMT
- Modified MMT
Who should you use observation/ movement activation/ palpation method?
- Infants, toddlers, children under 4 yo
- 4-6 yo who have trouble following directions or staying on task
- Children with cognitive impairments
Procedure for observation/ movement activation/ palpation method
- Observe posture and active movement
- Activate movement (tickle, tap, stroke muscle, position child, facilitate movement)
- Palpate
How to grade observation
- Present/Absent
- Apparently normal/weak/absent
- Describe any associated movement characteristics (compensations, synergies, etc)
Who should you use standard MMT with?
Children over 4, who can attend to tasks and follow directions
Grading standard MMT
0-3: same as adult
4,5: subjective, no norms, how much resistance?
Is intra-rater or inter-rater reliability better in standard MMT
intra-rater
Who should you use Modified MMT with?
- Children 4 yo and older
- Children who move with substitution patterns or synergistic movement patterns
Confusion sign
idk what it is
Modified MMT procedure
Use resistance only to point of substitution or synergy
Grading for modified MMT
*Standard 0-5 grading for non synergistic/ substitution movements
* Remember 4-5 grades have decreased reliability/ validity with children
*In-synergy or with substitution
3-: Moves through entire ROM against gravity
2-: Moves through entire ROM gravity eliminated
1+: Initiates movement in gravity eliminated position
What is the most reliable and precise method of testing muscle strength in children?
Dynamometer
What is strength correlated with?
weight, age, height, etc
What are the greatest predictors of strength?
body mass and age
What has the most influence on strength in young children
height
Test/Retest reliability for dynamometry
Varies by muscle group
Sensitivity/Specificity for Dynamometry
Varies per muscle group
Reliability systematic review for dynamometry with children with CP
- Inconclusive results
- Within session reliability + for lower extremity
- Between session reliability: + for some lower extremity muscle groups, but – for others
- Interrater reliability: - for all lower extremity muscle groups
Procedure for Dynamometry
*** MAKE TEST
* Less chance for injury
* Easier to control/more comfortable
* Sustain contraction for 5 sec
* Stabilize when measuring at hip/knee
* Make sure child understands instructions
* Take two measures and report MEAN
* Mean of 2 trials versus maximum contraction
How to perform dynamometry
- Dynamometer placement,
- PT position,
- Patient position,
- Be careful not to resist child’s isometric contraction
Standard Positions for dynamometry
- Hip flexion sitting and supine
- Hip extension in supine
- Knee extension and flexion in sitting
- Dorsiflexion in sitting
Who are isokinetics systems useful for?
Children who can fit isokinetic system (at least 6 years of age)
- Norms avail based on large sample 6-13 yo
Reliability for Isokinetic Systems
- 0.96 ICC for test-retest reliability – 10-13 year olds, knee flexion/extension
- Improves with training
- Need good fit of equipment
One of the major impairments of CP
- inadequate force generation
- Impact of abnormal muscle tone, synergy, and substitution
- Poor selective control of isolated muscle groups –> leads to poor reliability with some muscle groups
- Strength of spastic muscles versus antagonist muscle
Who is the most difficult group of children to test muscle strength reliably?
Children with CP
Recommendations for measuring muscle strength in children with CP
- Use dynamometer or functional testing
- Detectable strength changes with dynamometry are large
- Functional testing – age-appropriate functional testing
- Test all muscle groups
- Spastic muscles (out of synergy, in isolated movement)
- Antagonist to spastic muscles
How to test muscle endurance for children with CP
Distance can walk, wheelchair without substitution/ compensation/ synergy
When do you test muscle strength in children with myelomeningocele
- Newborn (pre-surgical)
- Approximately 10 days post surgical closure
- At regular intervals through adolescence and into adulthood
Presurgical Newborn testing for myelomeningocele
- Procedure
- Limited positions possible
- Observe movements
- Palpate
- Muscles tested
- Head/neck
- Trunk – above and below lesion
- Use of data
- Document pre-surgical muscle activity, help determine level of lesion
10 days post surgical testing for myelomeningocele
*Procedure
* Positioning precautions
* Observe, palpate, activate (as allowed)
*Muscles tested
* Same as in newborn
*Use of data
* Help identify level of lesion
* Intervention planning
* Prediction of functional outcome
Muscle Strength Testing throughout childhood for children with myelomeningocele
*Test at regular intervals
* Helps detect any negative changes (i.e. from tethered cord)
*Include neck, upper extremities, trunk
*Test at regular intervals (often as part of
Myelomeningocele Clinic)
* Every 3-6 mo through infancy
* Every 6 mo. Through young childhood
* Annually through adolescence/adulthood
Clinical Suggestions - Muscle strength testing in myelomeningocele
- Important to test individual, specific muscles
- Standardize procedure
Recommended methods of muscle strength testing in myelomeningocele
- MMT
- Dynamometer
- Functional Testing (muscle endurance)
MMT in Myelomeningocele
- MMT – most commonly used
- May not detect until > 50% deficit
- Limited test-retest, inter-rater reliability
- Need to have > 1 grade change to reflect true change in strength
- Predictive of later muscle strength
- Consider standard training and standard recording sheets
Dynamometry in myelomeningocele
- Good reliability (0.73-0.99)
- Standardize procedure – position, command, feedback/ reinforcement, application of R, body mechanics of examiner
- Recommend 3 trials – report MEAN
- Watch for substitutions
Minimum detectable change for dynamometry in myelomeningocele
15 N
