Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Regional Anatomy > Muscle Stretch Reflexes and Lower Limb Length > Flashcards

Muscle Stretch Reflexes and Lower Limb Length Flashcards

1
Q

When assessing the motor system what reflex is tested for

A
  • The muscle stretch reflex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the muscle stretch reflex allow us to test the health of for

A
  • Neurones of the stretch reflex.
  • Synapses of the stretch reflex
  • Wider circuits bult from the stretch reflex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What features must you look out for during a visual examination of the MSK system

A
  • Appearance of MSK muscles
  • Symmetry of muscle bulk
  • Location of libs and other muscle
  • Posture
  • Gait
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are some ways you can test for a patients ability to move

A
  • Evoking reflex movements
  • Displacement of a limb or muscle
  • Muscle tone
  • Any other specialist movements
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What makes up a motor unit

A
  • Alpha-motoneuron
  • All the muscle fibres supplied by the alpha-motoneuron
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is a reflex

A
  • Involuntary, unlearned, repeatable, automatic reaction to a specific stimulus that does not require the brain to be intact
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the neural pathway describing a reflex known as

A
  • Reflex arc
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 5 components that make up a reflex arc

A
  • A receptor
  • An afferent fibre
  • An integration centre
  • An efferent fibre
  • An effector organ
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the role of the muscle stretch reflex in neurology

A

-Basic template for all other motor circuits in the body.
- Underlies all movement of muscles of the body.
- Sets all the muscle tone of the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are muscle spindles

A
  • Muscle length receptors embedded within the fibres of the muscle
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what makes up the pathway that is known as the stretch reflex arc

A
  • Muscle spindles
  • Cell bodies of lower motoneurons
  • The synapse between the 2
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does the muscle stretch reflex occur

A
  • A muscle that is not contracting is relaxing (lengthening or stretching)
  • When the stretch is detected, action potentials are fired via muscle spindle afferent fibres which synapse with alpha-motoneurons in the spinal cord.
  • Action potential travels along alpha motoneurone towards NMJ where Ach is released.
    -m Ach causes muscle to contract and return to its original length.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What does the stretch reflex aim to maintain

A
  • Aims to maintain the muscle at a constant length
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are the action potentials from the afferent muscle spindle fibres also sent to

A
  • The cerebral cortex (via dorsal columns)
  • The cerebellum (via spino-cerebral tracts)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Where is the cell body of the spindle afferent fibres found

A
  • Dorsal root ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where do the axons synapse with the motoneuron

A
  • Level of ventral horn in lamina XI
17
Q

How does the axon of the alpha motoneuron leave the spinal cord and where does it go

A
  • Leaves via ventral roots
  • Leaves to supply muscle
18
Q

What is muscle tone also known as

A
  • Motor tone
19
Q

What is muscle tone

A
  • The small force a muscle has due to back ground minimal contractions.
20
Q

What causes background minimal contractions in a muscle

A
  • The background electrical impulses supplied by lower motoneurons in a normal awake neurological status.
21
Q

What is motor tone like in utero and early life

A
  • Present but low in utero
  • Supressed during birth (otherwise baby would resist birth)
  • Returns within months and informs of presence or absence of injury to the brain during birth
22
Q

When beside birth is muscle tone also inhibited and is this in all muscles?

A
  • During deep (REM) sleep in all muscles except:
    > Muscles of breathing
    > Extra-ocular muscles
    > Urinary sphincter muscles
    > Anal sphincter muscles
23
Q

What happens when to the body when it generates too little muscle tone

A
  • Becomes limp
  • Cannot support its weight
  • Normal posture is lost
  • Too little muscle tone can range from hypotonia (reduced muscle tone) to atonia (no muscle tone)
24
Q

What happens when to the body when it generates too much muscle tone

A
  • Normal body posture
  • The muscles become stiff
  • Spastic paralysis
  • Stiffness of joints and loss of ability to move
25
Q

What are some lower motoneuron nerve signs

A
  • Flaccid muscle weakness
  • Muscle hypotonia or atonia
  • Muscle hyporeflexia or areflexia
  • Denervation muscle atrophy
26
Q

What are the 2 skeletal structures that make the largest contribution to ones height and what are the respective percentages that they contibute

A
  • Vertebral column (42%)
  • Femur (25%)
27
Q

What percentage of the height of the vertebral column is attributed to the IVDs

A
  • Around 25% of vertebral column
  • Which is around 20 cm
28
Q

What part of the IVD is responsible for the size of the IVD

A
  • Central region - nucleus pulposus
29
Q

How many times in the day should height be measured for an accurate clinical reading and why is this

A
  • 3 times a day (ideally 8 hours apart)
  • The IVD’s ability to hold water changes throughout the day so height must be measured several times
30
Q

What are the palpable bony landmarks used to measure limb length

A
  • ASIS (of the hip)
  • Medial Malleolus (of the tibia)
31
Q

What are the 2 measurements of length of the lower limb

A
  • True length - lower tip of ASIS to lower tip of medial malleolus
  • Apparent length - Umbilicus to lower tip of medial malleolus
32
Q

What is a true length discrepancy

A

When the true length between the left and right lower limbs are not equal

33
Q

What is an apparent length discrepancy

A

When the apparent length between the left and right lower limbs are not equal

34
Q

What causes apparent shortening of the limb

A
  • Posterior dislocation of the hip joint
  • Congenital causes of hip dislocation
  • Tilting of the hip (due to things like scoliosis)
35
Q

What causes true shortening of the limb

A
  • A congenitally short lower limb compared to the opposite side.
  • A fracture of one or more of the long bones of the lower limb (overlapping)
  • Disorders of growth
  • Scoliosis

Regional Anatomy (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions