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Flashcards in Tone Deck (14):


A state of slight contraction and readiness for immediate activation while muscles are at rest. State of muscle preparedness for action.



Muscles are hyper reactive to stimulation. Too much tension is in the muscles while they are at rest, causing over-reactive contractions. Muscles also sustain contractions longer than functionally needed and have difficulty returning to relaxed resting levels because they tend to re-fire easily.


Assessing muscle strength in neurological conditions Flaccid:

Flaccid: Muscle strength would be graded as “0”


Assessing muscle strength in neurological conditions Hypotonic/paretic:

Grade both agonists and antagonists for strength. As a general rule, muscle strength is typically no greater than 4- in muscles which are clinically hypotonic or paretic.


Assessing muscle strength in neurological conditions Hypertonic:

Agonists are not graded as contractions elicited are not fully volitional and/or functional due to their hyperactive resting state. Antagonists may be assessed for the ability to override the abnormal tone of agonists for functional use. If agonists have severe tone (see grading scales for tone below) and/or are fixed or patterned, however, it is not recommended to grade muscle strength in either muscle group. Therapist would instead focus purely on observed functional abilities/use of affected extremity.


Why should tone testing be performed at same time of day.

tone fluctuates from hour to hour and day to day”, which may affect the reliability of testing results, although results are generally considered more reliable when testing is performed at same time of day.



Elicited by persistent slow movement through muscle range. This is a state of increased tone, and may result in synergistic patterns when muscles are recruited.


Hypertonicity Additional characteristics:

• Difficulty initiating movement
• Difficult for antagonists to move against
• Tone increases in result to painful or noxious stimuli
• Also stimulated by fear, anxiety, and sensory overload



Velocity dependent increase in stretch reflex. Elicited by rapid movement through muscle range. It is considered a hyper excitability of the stretch reflexes.
• Clasp knife pattern:
• Clonus:


Clasp knife pattern:

Sudden catch or resistance followed by release. (This resistance is thought to be inhibited by Golgi organs in the tendons)



Involuntary, rhythmic muscular contractions and relaxations.



Simultaneous increase in agonist and antagonist muscle tone. Increased tone is seen throughout range of muscle excursion and is not dependent upon velocity.

• Cog wheel rigidity:
• Lead pipe rigidity:


Mild-Moderate-Severe Spasticity Scale:

• Mild - palpable catch at end range (of flexion or extension)
• Moderate – Catch at mid-range
• Severe – Palpable catch at shortened range



Absence of muscle tone. Muscles will feel soft and flabby, and extremity will feel heavy during passive movement.