Quiz on Muscle Tone and Spasticity

Which of the following best describes muscle tone?

• The maximal force a muscle can generate

• The resistance of muscle to passive stretch

• The speed of muscle contraction

• The amount of muscle bulk

Muscle tone is primarily regulated by which part of the central nervous system?

• Cerebellum

• Basal ganglia

• Spinal cord

• Brainstem

Hypotonia is characterized by:

• Increased resistance to passive movement

• Decreased resistance to passive movement

• Normal resistance to passive movement

• Variable resistance depending on the muscle

Which clinical sign is NOT typically associated with hypertonia?

• Clonus

• Spasticity

• Rigidity

• Flaccidity

Spasticity is most commonly associated with lesions in which part of the central nervous system?

• Spinal cord

• Basal ganglia

• Cerebral cortex

• Cerebellum

The clasp-knife phenomenon is characteristic of:

• Hypotonia

• Rigidity

• Spasticity

• Ataxia

Rigidity, as seen in Parkinson's disease, differs from spasticity in that it:

• Is velocity-dependent

• Is uniform throughout the range of motion

• Is more pronounced in the lower limbs

• Involves the pyramidal tracts

Which of the following is a key feature of decerebrate rigidity?

• Flexion of the upper limbs

• Extension of all four limbs

• Flexion of the lower limbs

• Asymmetric limb posturing

The stretch reflex hyperactivity in spasticity is primarily due to:

• Increased activity of alpha motor neurons

• Decreased inhibition from the brain

• Increased sensitivity of muscle spindles

• All of the above

Spasticity often results from damage to which descending motor pathways?

• Corticospinal tract

• Rubrospinal tract

• Reticulospinal tract

• Vestibulospinal tract