Week 3

How should you correctly test the L3 myotome?

• Ask the individual to dorsiflex at the ankle against resistance

• Ask the individual to flex at the hip against resistance

• Ask the individual to flex at the knee against resistance

• Ask the individual to extend at the knee against resistance

What statement best describes gamma motor neurons?

• Gamma motor neurons adjust the length of intrafusal muscle fibers

• Gamma motor neurons are sensitive to the force of muscle contraction

• Gamma motor neurons are responsible for producing contraction of extrafusal muscle fibers

• Gamma motor neurons are the efferent component of Golgi tendon organs

Which statement best characterizes the difference between the medial and lateral vestibulospinal tracts?

• the medial vestibulospinal tract coordinates overall posture and balance and the lateral vestibulospinal tract coordinates limb extensor control.

• the medial vestibulospinal tract responds to signals regarding head movement and position, whereas the lateral vestibulospinal tract responds to orientation to gravity

• the medial vestibulospinal tract responds to signals regarding orientation to gravity, whereas the lateral vestibulospinal tract responds to head movement and position.

• the medial vestibulospinal tract sends signals down throughout the spinal cord whereas the lateral vestibulospinal tract sends signals as far as the thoracic level only

Which of the following spinal segments is associated with the correct myotome?

• C5, shoulder flexion

• C6, wrist extension

• C7, finger flexion or thumb abduction

• C8, elbow extension

How would you describe spasticity?

• involuntary rhythmic movements

• a rapid decrease in resistance when flexing a joint

• an increased resistance to stretch of a muscle

• loss of movement fractionation

What would happen if only gamma motor neurons were selectively damaged?

• Proprioception would be less accurate

• Muscles would be weaker

• Muscles could not contract

• Muscles would be more excitable

The clinical electromyography report on your client is as follows:  "The motor unit potentials during weak contractions were similar compared to normal.  During strong contractions, the interference pattern was showing a low firing rate".  This individual likely has:

• a disorder of the motor neuron

• a demyelinating disorder of the peripheral nerve

• a myopathic disorder

• a disorder of the motor tract

Using a reflex hammer to the biceps tendon tests the integrity of what spinal level motor control?

• muscle synergy

• withdrawal and crossed extension

• phasic stretch reflex

• Golgi tendon organ

What statement best describes synergy?

• a pathological reflex involving extension of the great toe and fanning of the other toes

• characteristic pattern of flexion of the upper limb and extension of the lower limb after brain injury

• a period after injury to the central nervous system characterized by hypotonia

• oscillatory contraction and relaxation of a muscle in response to stretch

• increased muscle tone and resistance to active and passive movements

What structure is labeled with a S?

• rubrospinal tract

• vestibulospinal tract

• lateral corticospinal tract

• reticulospinal tract