A07 Disorders of Upper and Lower Motor Neurones

Question 1

List the components of motor pathways.

Answer 1

1 - An upper motoneurone.

2 - A lower motoneurone.

3 - A neuromuscular junction.

4 - Skeletal muscle.

Question 2

What does the extrapyramidal system consist of?

Answer 2

Circuits between basal ganglia and the motor cortex.

Question 3

List the functions of the extrapyramidal system.

Answer 3

Control of:

1 - Muscle tone.

2 - Posture.

3 - Initiation of movement.

Question 4

List 5 consequences of lesions to the extrapyramidal system.

Answer 4

1 - An increase in tone known as leadpipe rigidity. Unlike spasticity, it is constant throughout the range and speed of movement.

2 - Bradykinesia.

3 - Involuntary movements.

4 - Tremor which, in combination with rigidity, produces cogwheel rigidity.

5 - Postural instability.

Question 5

Define hemiparesis.

What does this indicate?

Answer 5

• Weakness affecting one side of the body.

- It is indicative of a lesion to the contralateral cortex.

Question 6

Define paraparesis.

What does this indicate?

Answer 6

• Weakness affecting both lower limbs.

- It is indicative of a lesion to the spinal cord.