Brainscape's Knowledge GenomeTM

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


See full index

Musculoskeletal System > Week 4 - Dermatomes and Myotomes > Flashcards

Week 4 - Dermatomes and Myotomes Flashcards

1
Q

What is the adult nervous supply to the dermis and muscle of a dermamyotome?

A

A spinal segmental nerve

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

What is the spinal cord?

A

A cylindrical column of millions of nerve cell bodies and millions of neuronal axons

  • Starts where the medulla of the brain ends
  • It ends as the conus medullaris (where its membranes taper into a ligament; filum terminale)
  • It runs through successive vertebral foramina of most, but not all, vertebrae of the vertebral column
  • Shorter than the vertebral column
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a vertebral segment?

A

Each vertebra of the vertebral column makes 1 vertebral segment (known as a neural level)
- There are vertebral foramen and intervertebral foramen

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

What are intervertebral foramen?

A

When successive vertebrae are joined and viewed from side-to-side there are successive side openings between them

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

What forms the spinal canal?

A

Successive foramina of vertebrae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where does the spinal cord give off nerves?

A

Gives off a pair at each vertebral level (1 right and 1 left)

  • These leave the spinal canal via intervertebral foramina
  • Also known as segmental nerves or mixed spinal nerves
  • In the cervical cord: spinal nerves emerge superior to their corresponding vertebral levels
  • In the non-cervical cord: spinal nerves emerge inferior to their corresponding vertebral levels
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the shape of the spinal cord?

A

2 enlargements at the cervical and lumbar levels

- Ends in a taper

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

What does each segmental nerve compromise of?

A
  • Dorsal roots (sensory/afferent)

- Ventral roots (efferent, can be motor or autonomic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the effect of overlap between adjacent dermatomes?

A

This is normal

  • Some sections of skin are served by 2 successive spinal nerves
  • A typical dermatome will be served by 3 successive sensory nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where does the upper limb receive its nerve supply from?

A

It receives all of it from the spinal cord

  • Most is derived from C5-T1 roots
  • The rest comes from T2 roots
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What nerves are found in the upper limb?

A 
Brachial plexus nerves
- Radial
- Musculocutaneous
- Ulnar
- Axillary
- Median
Other nerves
- Lateral pectoral
- Upper subscapular
- Lower subscapular
- Dorsal scapular
- Suprascapular
- Long thoracic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Where does the lower limb receive its nerve supply from?

A

It receives all of it from the spinal cord

  • Supplied from the lumbar and sacral spinal segments (L1-S4)
  • The spinal nerves originate from 2 separate networks of nerves (Lumbar plexus (L1-L4), sacral plexus (L4-S4)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the lumbar plexus

A
  • Forms behind the psoas major muscle
  • Nerves emerge either medially or laterally to the borders of the psoas major muscle
  • Nerves emerging laterally = femoral (L2-L4), iliohypogastric, ilioinguinal, lateral cutaneous nerve of the thigh
  • Nerves emerging medially = obturator nerve, lumbosacral trunk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the sacral plexus

A
  • Composed of lumbosacral trunk (half of L4, all of L5)
  • Forms within the pelvic cavity
  • Lies in relation to piriformis
  • Sacral spinal segmental outflow
  • Supplies: pelvic region, gluteal region, perineal region, lower limb via the sciatic nerve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the axial lines of limbs?

A

The line of junction of 2 dermatomes supplied from discontinuous spinal levels

  • Limbs have posterior and anterior axial lines
  • Can be said to mark boundaries between the flexor and extensor compartments of the limb (marked out by veins; cephalic and basilic, great saphenous and small saphenous)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are nerve territories?

A

The area of skin that a nerve from the brachial plexus innervates
- Different to a dermatome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What muscles are there in the anterior forearm?

A 
1st layer (lateral to medial):
- Pronator teres
- Flexor carpi radialis
- Palmaris longus
- Flexor carpi ulnaris
2nd layer:
- Flexor digitorum superficialis
3rd layer:
- Flexor pollicis longus
- Flexor digitorum profundus
4th layer:
- Pronator quadratus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What innervates the pronator teres?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What innervates the flexor carpi radialis?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What innervates the palmaris longus?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What innervates the flexor carpi ulnaris?

A

Ulnar nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What innervates the flexor digitorum superficialis?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What innervates the flexor pollicis longus?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What innervates the flexor digitorum profundum?

A
  • Medial half = ulnar nerve

- Lateral half = median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What innervates the pronator quadratus?

A

Median nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the action of the pronator teres?

A

Pronation of the forearm

27
Q

What is the action of the flexor carpi radialis?

A

Flexion and adduction at the wrist

28
Q

What is the action of the palmaris longus?

A

Flexion at the wrist

29
Q

What is the action of the flexor carpi ulnaris?

A

Flexes and adducts at the wrist

30
Q

What is the action of the flexor digitorum superficialis?

A
  • Flexes the metacarpophalangeal joints at the fingers
  • Flexes the proximal interphalangeal joints at the fingers
  • Flexes at the wrist
31
Q

What is the action of the flexor pollicis longus?

A
  • Flexes the interphalangeal joint of the thumb

- Flexes the metacarpophalangeal joint of the thumb

32
Q

What is the action of the flexor digitorum profundus?

A
  • Flexes the distal interphalangeal joints of the fingers
  • Flexes the metacarpophalangeal joints of the fingers
  • Flexes the wrist
33
Q

What is the action of the pronator quadratus?

A

Pronates the forearm

34
Q

What are the common types of joint injury?

A
  • Sprains
  • Fractures
  • Subluxations
  • Dislocations
  • Fracture dislocation/subluxation
35
Q

What should you ask about to find out the history of the injury?

A
  • Mechanism
  • Time scale
  • Ability to continue activity
  • Swelling
  • Weight bear
  • Weakness
  • Site of discomfort
  • Mechanical symptoms
36
Q

What should you look for when examining a joint injury?

A
  • Swelling
  • Bruising
  • Obvious deformity
  • Puncture/skin wounds
  • Joint fluid
  • Painful anatomical sites
  • Laxity (loose ligaments)
  • Crepitus (pops/snaps when bending joints)
  • Range of movement
  • Pulses difficult to feel
37
Q

What are some classic nerve associations with joint injuries?

A
  • Axillary nerve injury and shoulder dislocation
  • Sciatic nerve injury and hip dislocation
  • Median nerve and colles fracture
  • Arterial injury/common perennial nerve and knee dislocation
38
Q

What should you do when assessing a joint injury?

A
  • Can use gas and air, sedate, use local anaesthetic or put fully asleep to relieve pain/discomfort
  • Check for neuromuscular damage
39
Q

What investigations can you do for joint injuries?

A
  • X-rays
  • Stress views (type of x-ray, demonstrate the amount of joint cartilage left)
  • Arthography (radioluscent dye is injected into the bloodstream which will eventually absorb into the joint, or injected directly into the joint)
  • MRI
  • CT scan
  • Aspiration (drain fluid from joint; if fat is present then there is a fracture, fat from bone marrow)
40
Q

What treatments can you do for joint injuries?

A 
Determined by the type of injury and individual patient circumstances
Take photographs if possible
Open injuries require:
- Ιmmediate cleaning
- Irrigation and reduction
- Tetanus status
- Coverage of wound
Subsequently need surgical debridement/washout and fixation as an emergency
41
Q

Describe a sprain

A

Damage to a ligament

  • Can be complete (may require surgery) or partial
  • They have damaged fibres with continuity intact
  • Mechanisms: forces which stress the ligaments
42
Q

What are the common sites for sprains?

A
  • Ankle
  • Knee
  • Joints of the hand (usually thumb)
43
Q

Describe a dislocation

A

Complete loss of continuity of the articulating surface of the joint

44
Q

What are the common sites for dislocations?

A
  • Fingers

- Shoulder (anterior or posterior)

45
Q

Describe a subluxation

A

A partial loss of continuity of the articulating surfaces of the joint

46
Q

What are the common sites for subluxations?

A

Shoulder joint

47
Q

Describe a fracture

A

A break in the continuity of bone

- Causes = stress, trauma, deficiency, pathological

48
Q

When assessing a fracture, what do you look for?

A
  • Position
  • Open or closed?
  • Displacement
  • Depression
  • Comminution (small fragments)
  • Quality of bone
49
Q

What are the aims of fracture treatment?

A
  • Pain relief
  • Prevent infection
  • Restoration of normal joint anatomy as far as possible
  • Maintenance of position
  • Monitor healing process
  • Rehabilitate
50
Q

What are the different methods of treatments for joint injuries?

A
  • Conservation and support
  • Manipulate and hold with cash
  • Manipulate and insert wires
  • Open reduction internal fixation (screws, plates, wires, combinations)
  • External fixation
  • Arthroplasty
  • Excision
  • Osteotomy (re-align)
  • Amputation
  • Arthrodesis
51
Q

What are some characteristics of hip fractures?

A
  • Very common
  • High associated mortality (since often seen in the elderly)
  • Usually managed operatively
  • Consequences of injury: pain, stiffness, deformity, loss of function, cosmetically poor
52
Q

What are the different types of hip fractures?

A
  • Intracapsular

- Extracapsular

53
Q

What happens if a fracture/dislocation tears the capsule and ligament in the hip joint?

A

Blood supply to the femur head is very important

  • If this happens, then blood supply is lost
  • It causes necrosis
54
Q

What is a Colles’ fracture?

A

Common wrist fracture

  • Common in elderly people with low bone density
  • A transverse fracture of the distal radius with dorsal displacement and shortening of the wrist
  • Often accompanied by a fracture of the ulnar styloid
55
Q

What is a Smith’s fracture?

A

Common wrist fracture

  • Distal radius fracture
  • Palmar displacement and angulation
  • Shortened radius
  • Causes soft tissue swelling
  • Distal fragment is placed anteriorly
  • Opposite of colles’
56
Q

What is the course of the ulnar nerve?

A

Travels down the medial side of the anterior arm

  • Passes posterior to the medial epicondyle
  • Pierces the 2 heads of the flexor carpi ulnaris
  • Continues down the medial side of the anterior forearm
57
Q

What is the course of the median nerve?

A

Travels down the medial side of the anterior arm, but lateral to the ulnar nerve

  • Enters into the anterior compartment of the forearm via the cubital fossa
  • Crosses over the brachial artery to become situated in the middle of the anterior arm
  • Travels between the flexor digitorum profundus and the flexor digitorum superficialis muscles
  • Enters the hand via the carpal tunnel
58
Q

What is the course of the radial nerve?

A

Travels down the posterior arm (mainly)

  • Travels in the radial groove of the humerus
  • Accompanied by the brachial artery
  • Moves anteriorly over the lateral epicondyle, through the cubital fossa
  • Splits into a superficial branch and a deep branch once it enters the forearm
59
Q

What happens to the brachial artery in the distal region of the cubital fossa?

A

It bifurcates into the radial and ulnar artery

60
Q

Where does the radial artery run?

A

From the distal region of the cubital fossa

- Between the brachioradialis and flexor pollicis

61
Q

Where does the ulnar artery run?

A

From the distal region of the cubital fossa

- Between the flexor carpi ulnas and flexor digitorum profundus

62
Q

What deep veins are found in the anterior forearm?

A
  • Radial veins
  • Interosseous veins
  • Ulnar veins
  • Deep venous arcade
  • Accompanying veins of the superficial palmar arch
63
Q

What superficial veins are found in the anterior forearm?

A
  • Cephalic vein (from the dorsal venous network of the hand)
  • Basilic vein (from the dorsal venous network of the hand)
  • Median cubital vein (connects the cephalic and basilic veins in the cubital fossa)
64
Q

List the myotomes

A
  • C5 = Elbow flexion
  • C6 = Wrist extension
  • C7 = Elbow extension
  • C8 = Finger flexion
  • T1 = Finger abduction
  • L2 = Hip flexion
  • L3 = Knee extension
  • L4 = Ankle dorsiflexion
  • L5 = Great toe extension
  • S1 = Ankle plantarflexion

Musculoskeletal System (12 decks)

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