Final Exam Flashcards
Measuring Muscle Strength
- not good for people with functional deficits
- isotonic: constant external resistance; 1 RM, takes a long time
- isokinetic: resistance through whole ROM at constant velocity; isokinetic torque curve, highest point on curve/average distance
- isometric: immovable resistance-MMT and HHD
MMT
- assess muscle strength; essential before prescribing exercises
- formulate treatment
- assess effectiveness of treatment (periodically re-assess)
- indication for assistive devices
- differential diagnosis: patterns of strength deficits
- prognosis
Factors Affecting Strength
- anthropometry: muscle size, cross sectional size, circumference
- fiber type: type 1–>slow twitch and type 2–>fast twitch
- age: both cognitive and chronological (3-4years observation of functional activities)
- gender
- length of lever arms
- pain
MMT Assessment of Strength Dependent Upon
- point of resistance application
- stabilization
- positioning
- motivation and cognition
Proficient in MMT
- knowledge of joint motion
- knowledge of O&I
- ability to palpate muscles or tendons
- ability to distinguish between normal and atrophied contour
- ability to recognize abnormalities of position or movement
MMT Resistance
- direction of pressure is perpendicular to line of pull of muscle
- resistance is applied towards end of GR ROM
- location of resistance applied distally (some exceptions)
- exceptions: pain, pros and cons make sure to document
- midrange is the length of muscle that’s optimal for resistance
MMT Stabilization
- pertinent at proximal joint
- firmness or stability of body is necessary to insure accurate test
- do not stabilize over muscle belly
MMT Positioning
-ability of patient to move against gravity will determine testing position
MMT Palpation
- critical for weak muscles
- helps rule out substitutions
- confirms contraction of desired muscles
MMT Grading
- the higher on the scale (above a 3+) the less reliable the test
- partly due to size differentail
MMT Reliability
- the more standardized all the factors, the more reliable
- accuracy; do the same test on two different occasions and get the same result
- intrarater is more reliable
- highest in grades below 3
- lack of standardized testing procedures resulted in lower intrarater reliability
- interrater reliability improved when all testers used same standardization approach
MMT Valididty
- does test measure what it’s supposed to?
- research says MMT is valid procedure in measuring muscle strength especially for 4 and less
- limited correlations to other assessments in MMT grades above 4/5
- high correlations with MMT grades less than 4/5
MMT Strength
-maximal force a muscle (or group) can generate at a specified or determined velocity
Testing Vs. Screening
- testing: looking at each individual movement and knowing which muscles make that movement; increased time and effort, standardization technique, position specific, gravity specific positions, isolated movements/muscles
- screening: quick overview in position of convenience; difficult to rule out substitutions, weakness should be tested, combines movements in multiple planes, guides you in direction of testing
Vertebral Artery Test
- clearing neck means making sure you’re not blocking this vessel
- supine or sitting
- eyes open
- extend, rotate, side bend
- count backward from 20
- observe
- loss of vision in one or both eyes/double vision/nystagmus
- numbness/tingling hands or feet
- dizziness/vertigo
- slurred speech
- change in mental status
- sudden/severe weakness
- SpPin–>0% (specificity-ability of a test to rule something in)
- SnNout–>67-90% (sensitivity-ability to rule something out)
Elevations-Upper Trap and Levator Scapulae
- options 1 and 2 produce greatest EMG activity in upper trap fibers
- measured as percent max voluntary isometric contraction
Scapular Adduction (Middle Trap)
- lateral rotation of humerus is critical to achieve max activation of middle traps
- EMG show that when tested with this method but with IR EMG activity is reduced
- shoulder must be ER and horizontally abducted to have highest EMG
Scapular Adduction and Depression (Lower Traps)
- highest EMG when muscle is tested as we have been
- also involves significant activity in middle fibers of traps
Scapular Abduction and Upward Rotation (Serratus Anterior)
- low EMG in SA during tests that involve protraction
- highest when SA is tested as it is in book
Shoulder Abduction (Middle Deltoid and Supraspinatus)
- frontal plane
- significantly less EMG in middle and posterior fibers of deltoid during abduction in scapular plane rather than frontal)
- no other studies found that compared EMG activity or force produced in deltoid or supraspinatus during abduction in these two planes
- so testing deltoid and supraspinatus in this plane is appropriate
- some evidence for testing supraspinatus in scapular plane-common clinically (did in class)
- deltoid is key muscle for examining integrity of C5 spinal nerve or neurological segment of spinal cord, complete assessment of this includes strength testing of deltoid and biceps brachii, reflex testing of biceps, and sensory testing of skin over middle deltoid
Shoulder Abduction Scapular Plane (Supraspinatus)
- elevation of arm in scapular plane commonly used
- some controversy
- full can, empty can, and horizontal abduction of shoulder at 100 degrees from prone position with LR (prone full can)
- no statistically significant differences in amount of EMG during these 3 methods
- found decreased EMG in middle delt during empty can test
- concluded that mmt of supraspinatus could best performed with full can
Elbow Flexion (Brachialis and Brachioradialis)
- studies examined relative activation of these two during elbow flexion in varying degrees of forearm rotation show that biceps brachii demonstrates much higher levels of activity when flexing elbow with forearm pronated
- differences in activity between these two muscles due to forearm position much less likely: synergistic elbow flexors regardless of forearm position
- one may decrease activity in biceps brachii muscle by pronating forearm or may increase activity of biceps brachii by supinating forearm