Week 4 - Manual Muscle Testing Flashcards
The assessment of strength by a physical therapist can be done though ___.
Manual Muscle Testing
Where is Muscle Performance listed in the guide to physical therapist practice?
Test & Measurements
What does muscle performance include the assessment of?
Strength, Endurance, & Speed (or Power)
What is Strength?
Measureable force exerted by a muscle or group of muscles to overcome resistance in one maximal effort.
What is Endurance?
Ability to contract a muscle repeatedly over a period of time.
What is Power?
Work produced by the muscle per unit of time
What is the product of both ____ and ____.
What is the product of both Speed and Strength
Manual Muscle Testing focuses on this component of performance.
Strength
What are the 3 definitions of Muscle Strength?
- Ability to develop tension or torque.
- Force generated over a single unlimited episode against an immovable object.
- The maximal force a muscle or muscle group can generate at a specified or determined velocity.
What are the 3 primary approaches to determining muscle strength?
- Isotonic
- Isokinetic
- Isometric
What is an isotonic contraction traditionally defined as?
testing of strength using a constant external resistance.
What does isotonic actually refer to?
“constant” muscle tension which rarely occurs in muscle
Because isotonic rarely occurs, what do we usually refer to the type of contraction as well as strength the muscle is generating during the activity?
Concentric vs. Eccentric
What is Concentric contraction?
Shortening contraction of the muscle
What is Eccentric contraction?
Lengthening contraction of the muscle
What do we usually use to assess the concentric and eccentric strength of the muscle?
Free Weights or Resistance Machines
Traditionally, how is strength assessed?
Using a 1 repetition max
What is use besides a 1 rep max and why?
Because 1 rep max could be detrimental to subject, usually MULTIPLE REPS are used to determine the MAX weight a subject can lift or move.
What is the most common number multiple repetition max used today?
3 repetition
In general, when using free weights or resistance machines to assess concentric or eccentric contraction, are we assessing the gross strength of muscle groups or the strength of individual muscles?
The gross strength of muscle groups (even though with certain patients we will be interested in the strength of specific muscles)
When did isokinetics become developed?
1960’s with introduction of isokinetic dynamometer
What does an isokinetic dynamometer allow measurement of?
Strength by having subject provide resistance through the ROM at a constant velocity
What does an isokinetic dynamometer provide?
“Peak Torque” values at specific points or throughout full ROM.
Are reliability of isokinetic dynamometer low or high?
High if test protocols are followed precisely.
What are the disadvantages of using isokinetic dynamomenter? (2)
- Cost of equipment is high (>= $40,000)
- Considered nonfunctional since strength of assessed in a non-weight bearing
(however still used to assess speed of contraction in atheletes)
How is muscle length during an isometric contraction?
remains “almost” the same throughout the contraction. (during the initial stages of contraction there will be movement in the muscle as the actin and myosin filaments interact to generate tension)
How is the testing of isometric muscle strength done?
by having muscle generate force against an immovable resistance.
T/F: Muscle length is unchanged during an isometric contraction.
True
What is the advantage of muscle length remaining unchanged during an isometric muscle strength test?
Issues associated with variability in muscle length and velocity of joint motion are eliminated.
What are the most common methods of Isometric Testing?
Manual Muscle Testing (MMT) Handheld dynamometry (HHD)
What is the disadvantage of isometric testing?
Provides muscle strength data at only one point in ROM (as a muscle undergoes contraction through the full range of motion different fibers will be recruited throughout that activity.
What must be considered when selecting a muscle test? (3)
- Which method is most appropriate based on patient’s muscle strength?
- Must consider patients age
- Best tools that fits our current practice environment
What are patient’s with significant muscle weakness best assessed using? Why?
MMT
HHD and other instrumented forms of muscle testing may not be sensitive enough to detect low levels of strength.
At which strength range should a patient not be tested with MMT? Why?
Good (4) to Normal (5)
MMT does not delineate between gradations of muscle strength in these ranges.
If a patient should not be tested with MMT due to their strength range, what should be used?
Consider using HHD, strength testing (10 rep max) or isokinetic dynamometry
Why must you consider a patients age when selecting a muscle test for young children?
Young children may not have concentration or ability to understand the necessary instructions for MMT.
Why must you consider a patients age when selecting a muscle test for elderly?
Elderly individuals may not be able to tolerate certain positions or have the balance/motor control to perform tasks required for testing
Why must you consider the best tools that fits our current practice environment?
Home visit or free clinic will not have the accessibility to expensive equipment.
If more than one method of muscle strength testing is available, which should the PT select?
PT should select the method that provides the most objective and quantifiable data.
MMT remains that method of choice for the assessment of muscle strength of which patient’s?
those whose muscle test grades fall below FAIR+ (3+)
Which is the most convenient and inexpensive method of muscle strength assessment?
MMT
Manual Muscle Testing (MMT) was designed to measure what?
muscle strength which is defined as ability of muscle to develop isometric tension against resistance.
During MMT, what is done to each muscle?
Each muscle is isolated as much as possible within the available ROM and according to function, then give a grade of strength.
Which is one of the oldest test and measurements performed by PTs?
MMT
What is the history of MMT?
Developed during poliomyelitis epidemics during the early 1900s
MMT provided means for PT to assess level of paralysis in the individual with polio.
As the threat of polio subsided, MMT used as a test and measure for other neuromusculoskeletal diseases and trauma including (5).
- Spinal cord injuries
- Guillain-Barre syndrome
- Muscular Dystrophy
- Multiple Sclerosis
- RA and OA
PTs recognized for the development of MMT (2)
- The Kendall’s
2. Daniels, Williams, and Worthingham