9/4c Intro to Muscle Performance Flashcards
what composes muscle perf?
strength
muscle activity
define strength
maximal force a muscle or muscle group can generate at a specified or determined velocity
define muscle activity
found using electromyography (EMG)
strength testing does NOT measure muscle activity
Why do we test muscle strength?****
using strength/muscle testing is part of every aspect of the APTA management model
-measure at IE and systematically remeasure to make sure we’re making the right decisions as clincians
Approaches to strength testing
- Isotonic: 1-RM
- Isokinetic: Dynamometer
- Isometric: MMT, Dynamometer, Hand Held Device (HHD)
MMT
Manual Muscle Testing
- a system of measurement using manually applied resistance to determine the strength of a muscle
- gravity based
- quantifies muscle strength
- reliability adequate
- ordinal measurement scale (6 points)
Normal
- N/5
- able to move through the full available range of motion
- against gravity
- able to hold against MAX resistance
Good
- G/4
- able to move through full available range of motion
- against gravity
- able to hold against MOD resistance
Fair +
- F+/3+
- able to move through full available range of motion
- against gravity
- able to hold against MIN resistance
**Fair
- F/3
- able to move through full available range of motion
- against gravity
- NO manual resistance (patient doesn’t accept ANY resistance)
Fair -
- F-/3-
- able to move through more than half available range of motion
- against gravity
- NO manual resistance
Poor +
- P+/2+
- able to move through less than half available range ofmotion
- against gravity
Poor
- P/2
- move through the full available range
- gravity minimized
Poor -
- P-/2-
- move through partial range
- gravity minimized
Trace
- T/1
- no joint motion
- gravity minimized
- muscle contraction palpable/observable
Zero
- 0
- no observable/palpable muscle contraction
***Gravity based system
gravity minimized position, side lying allows for gravity to take over
procedure for MMT
- explain purpose to patient
- position patient and expose part
- begin with fair test position (allow patient to do exercise on their own)
- stabilize
- palpate
- add resistance
- if
Testing muscles above 3 on the scale require manual resistance. What are the two possible tests?
- Break test - PT pushes as hard as they can until the patient breaks their position
- Make test - Patient has to push as hard as they can into the PT’s hand until they make a force big enough to break the PT’s position
**99% of the time which MMT test for a patient performing above 3 on the scale is necessary?
Break test, because it yields much higher force output from the patient than the make test
*****when testing strength what are other key factors?
-operational definitil
-function of age, size, gender
-symmetry
-substitution/compensation
-pain: **Ensure documented on visual analog scale
-Motivation
Decreased ROM
Special Grades that don’t need these scales now:
fingers, toes, facial muscles, trunk, weight bearing muscles
**MMT Validity
- Grades above 4 - not strong
- Grades BELOW 4 - STRONG
- Variable depending on: muscle tested, experience/edu of tester, and patient’s motivation, understanding and fatigue
*****MMT Reliability
- INTRArater - reliability is good (same person on same person)
- ITERrater - reliability is fait/good (one person on another)
- standardized methods are required
- in general grades >=4 are less reliable
**Errors affecting reliability of MMT
- submax contractions
- substitution/compensation
- report of wrong side
*****Strengths of MMT
Strengths - always available, inexpensive, useful for individual muscles
Weaknesses - imprecise, reliability, ceiling effects
