The Foot - Intrinsic Muscles Flashcards

1
Q

Where are the intrinsic muscles of the foot located? What movements are they responsible for?

A

The intrinsic muscles are located within the foot and are responsible for the fine motor actions of the foot, for example movement of individual digits.

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

What 2 groups can the intrinsic muscles of the foot be divided into?

A

Dorsal and plantar aspect

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

Which intrinsic muscles are located in the dorsal aspect of the foot?

A
  • Extensor digitorum brevis
  • Extensor hallucis brevis
  • A group of 4 dorsal interossei (between the metatarsals)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where does EDB lie?

A

Lies deep to EDL

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

Origin and insertion of EDB?

A

Origin: calcaneus

Inserts: proximal phalanges of digits 2-5

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

Action of EDB?

A

Aids the extensor digitorum longus in extending the medial four toes at the metatarsophalangeal and interphalangeal joints.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Innervation of EDB?

A

Deep fibular nerve

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

Origin and insertion of EHB?

A

Origin: calcaneus

Inserts: proximal phalanx of big toe

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

Action of EHB?

A

Aids the extensor hallucis longus in extending the great toe at the metatarsophalangeal joint.

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

Innervation of EHB?

A

Deep fibular nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where are the 4 dorsal interossei located?

A

Between the metatarsals. Each arises from two metatarsals.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Origin and insertion of the dorsal interossei?

A

Originates from the sides of metatarsals one to five. The first muscle attaches to the medial side of the proximal phalanx of the second digit. The second to fourth interossei attach to the lateral sides of the proximal phalanxes of digits two to four.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Action of the dorsal interossei?

A

Abduct digits two to four and flex the metatarsophalangeal joints.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Innervation of the dorsal interossei?

A

Lateral plantar nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are the intrinsic muscles of the plantar aspect of the foot arranged?

A

Arranged in four layers, superficial to deep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What muscles are found in the most superficial layer of the plantar aspect?

A

Flexor digitorum brevis, abductor hallucis, abductor digiti minimi

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

What muscles are found in the second most superficial layer of the plantar aspect?

A

The tendons of FHL and FDL (extrinsic muscles), the lumbricals, quadratus plantae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What muscles are found in the third most superficial layer of the plantar aspect?

A

Flexor hallucis brevis, flexor digiti minimi and adductor hallucis

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

What muscles are found in the deepest layer of the plantar aspect of the foot?

A

The plantar interossei - there are 3 of these

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

Function of the muscles of the superficial layer of the plantar aspect?

A
  • Abductor Hallucis - abducts and flexes the great toe
  • Flexor Digitorum Brevis - Flexes the lateral four digits at the proximal interphalangeal joints.
  • Abductor Digiti Minimi - Abducts and flexes the 5th digit.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Function of the second layer of the muscles of the plantar aspect?

A
  • Quadratus Plantae - Assists flexor digitorum longus in flexing the lateral four digits.
  • Lumbricals - Flexes at the metatarsophalangeal joints, while extending the interphalangeal joints.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Function of the third layer of the muscles of the plantar aspect?

A
  • Flexor Hallucis Brevis - Flexes the proximal phalanx of the great toe at the metatarsophalangeal joint.
  • Adductor Hallucis - Adduct the great toe. Assists in forming the transverse arch of the foot.
  • Flexor Digiti Minimi Brevis - Flexes the proximal phalanx of the fifth digit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Function of the deepest layer of muscles of the plantar aspect?

A

Plantar interossei - Adduct digits three to five and flex the metatarsophalangeal joints.

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

Where does flexor hallucis longus insert?

A

Distal phalanx of big toe (sole of foot)

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

Where does fibularis longus insert?

A

Sole of the foot –> medial cuneiform and 1st metatarsal

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

Where does extensor digitorum longus insert?

A

Dorsum of foot –> distal phalanges of digits 2-5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is being pointed to?

A

Subtalar joint - between the calcaneum and talus

Eversion and inversion happens here

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What?

A

Navicular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What?

A

Cuboid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What?

A

Lateral cuneiform

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

The foot can deform according to what surface it is walking on. What is the purpose of this?

A

Helps to dissipate the forces –> shock absorber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Normal foot xrays

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

A 50 year old woman presented to her GP with deformity and pain in her feet.

This had been going on for some time, but the pain was now becoming severe and she was finding it painful to wear shoes.

What’s the diagnosis?

A

Bunions - ‘hallux valgus’

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How would you describe the abnormalities seen? What are some causative factors?

A
  • Deformities at the MTP joints of both feet
  • Bony protrustion is the head of the first metatarsal
  • Causative factors:
    • High heels
    • Poorly fitting shoes over a long period of time
    • Genetic element
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

A 48 year old man presented to his GP with with sudden onset severe pain, swelling and redness of his left foot, as shown. The patient was hobbling and wearing a flip-flop, as it was too painful for him to put on a shoe or sock.

What’s the diagnosis?

A
  • Gout
    • Typically first attack in 1st MTP joint
    • Sudden onset of pain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

How would you describe the abnormalities seen in this X-ray?

What’s happening inside the affected joints?

A
  • X-ray of gout
  • Joint erosion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

This patient had a history of pain and swelling in his right foot.

How would you describe the abnormalities seen?

A
  • X-ray of gout
  • Long term chronic gout can cause tophi –> nodular masses of monosodium urate crystals deposited in the soft tissues of the body
  • Punched out regions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

This patient had a history of chronic left foot pain and previous episodes of gout.

How would you describe the abnormalities seen?

A
  • Erosions at 1st MTPJ
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

A 26 year old man presented to A&E one evening with severe pain in his right heel. Earlier that day he had fallen about 2m from scaffolding at work, but had landed on his feet. His foot was painful immediately after but he thought it would get better. The pain however is worsening and he can’t walk on that foot because of pain.

  • What’s the diagnosis?
  • What action should be taken now?
A
  • 2 radiolucent lines in the calcaneum –> fracture of the calcaneum
  • Need to examine lower limbs, joints, pelvis, vertebral column
    • Large forces required to break calcaneum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

On a Radiology placement the registrar asks you what you think about this X-ray.

  • How would you describe the abnormalities in this X-ray?
  • Which joints are affected? What has happened to them?
  • What’s the diagnosis?
A
  • Rheumatoid arthritis
    • Predominantly affects the MTP joints and PIP joints
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

The intrinsic muscles in the sole of the foot are innervated by which nerves?

A
  • Lateral and medial plantar nerves
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is this?

A

Plantar aponeurosis - a flat band of fibrous tissue that lies deep to the skin

43
Q

Where does pain from plantar fascitis tend to present?

A

Heel pain which radiates forward into the sole of the foot

44
Q

What is this?

A

Abductor hallucis –> tendon travels up on medial aspect of big toe

45
Q

What is this?

A

Abductor digiti minimi –> tendon runs up on lateral aspect of 5th digitis

46
Q

What is this?

A

Flexor digitorum brevis –> 4 tendons that run to each tendon, assists flexor digitorum longus in flexing the toes

47
Q

What is characteristic of the 2nd layer of the sole of the foot?

A

Tendon of flexor digitorum longus (running through middle towards toes)

48
Q

Which malleolus does flexor digitorum longus pass to get into the foot?

A

Its tendon passes behind the medial malleolus of the ankle, and enters the sole in its medial side.

49
Q

Which muscles arise from the tendons of FDL?

A

Lumbricals

50
Q

What is this? What is its action?

A

Quadratus plantae –> inserts onto tendon of FDL and assists FDL in flexing the toes

51
Q

What nerve is this?

A

Medial plantar nerve

52
Q

What nerve is this?

A

Lateral plantar nerve

53
Q

What are the medial and lateral plantar nerves the terminal branches of?

A

The tibial nerve

54
Q

How does the tibial nerve enter the foot?

A

Passes down posterior aspect of leg and behind the medial malleolus into the sole of the foot

55
Q

What do the medial and plantar nerves innervate?

A

The muscles of the sole of the foot

56
Q

What is this tendon?

A

Tendon of flexor hallucis longus

57
Q

How does the tendon of FHL enter the foot?

A

Down posterior leg and behind the medial malleolus

58
Q

What is this fleshy muscle directly deep to FHL tendon? What layer of the sole of the foot is this found in?

A

Flexor hallucis brevis muscle - found in 3rd layer

59
Q

Flexor hallucis brevis is mirrored on the opposite side. What fleshy muscle is this? What layer of the sole of the foot is this found in?

A

Flexor digiti minimi –> found in 3rd layer of the foot

60
Q

What muscle is found alongside FHB and FDM in the 3rd layer?

A

Adductor hallucis

61
Q

What is this?

A

Abductor hallucis

62
Q

What is this?

A

Abductor digiti minimi

63
Q

What is this?

A

Flexor digitorum brevis

64
Q

What is this?

A

Quadratus plantae

65
Q

What is this?

A

Tendons of FDL

66
Q

What are these? What are they attached to?

A

Lumbricals - attached to tendons of FDL

67
Q

What is this?

A

Tendon of FHL

68
Q

What is this?

A

Muscle of FHB

69
Q

What is this?

A

FDM

70
Q

What are the muscles of the 3rd layer of the foot?

A
  1. Flexor hallucis brevis
  2. Flexor digiti minimi
  3. Adductor hallucis
71
Q

What is this?

A

Oblique part of adductor hallucis (N.B. also has a transverse head but this has been removed)

72
Q

What is this?

A

Tendon of FHL

73
Q

What are these?

A

The plantar interossei (3 of them)

74
Q

Sensory innervation of the sole of the foot

A
75
Q

What is the saphenous nerve a branch of?

A

The terminal cutaneous branch of the femoral nerve. It travels through the adductor canal (accompanied by the femoral artery and vein) and exits prior to the adductor hiatus.

76
Q

What skin of the sole of the foot does the medial plantar nerve innervate?

A

Medial 3 1/2 toes

77
Q

What skin of the sole of the foot does the lateral plantar nerve innervate?

A

Lateral 1 1/2 toes

78
Q

What skin of the sole of the foot does the tibial nerve innervate?

A

Sole of foot near heel

79
Q

What supplies the majority of the sensory innervation of the sole of the foot?

A

The tibial nerve or its branches

80
Q

What supplies the majority of the sensory innervation of the dorsum of the foot?

A

Superficial fibular nerve

81
Q

Innervation of dorsum of the foot

A
82
Q

What is this a tendon of?

A

Tibialis anterior

83
Q

What is this?

A

The 1st dorsal interosseus

84
Q

What is this vessel? What is it a continuation of?

A

Dorsalis pedis artery - continuation of the anterior tibial artery

85
Q

What runs alongside dorsalis pedis?

A

2 deep veins (on either side)

86
Q

What is this very fine structure? How does it enter the foot? What happens when it approaches the toes?

A

The deep fibular nerve - passes down anterior aspect of leg (innervating anterior muscles), over the dorsum and then divides into 2 branches as it approaches the toes

87
Q

What sensory innervation does the deep fibular nerve provide in the dorsum of the foot?

A

1st web space (between 1st and 2nd toe)

88
Q

What is this muscle? What is it innervated by?

A

Extensor digitorum brevis –> innervated by the deep fibular nerve

89
Q

What is this the tendon of?

A

Extensor hallucis longus

90
Q

What are these the tendons of?

A

Extensor hallucis longus

91
Q

What is this small muscle on the lateral aspect of the foot?

A

Extensor digitorum brevis

92
Q

What tendon is this? What is this a part of?

A

Extensor hallucis brevis (a part of extensor digitorum brevis)

93
Q

Function of EDB?

A

Sends very thin tendons to digits 2, 3 and 4 - assists EDL in extension of the toes

94
Q

What does the deep fibular nerve innervate in the dorsum of the foot?

A

EDB and EHB

95
Q

Where can you palpate the dorsalis pedis artery?

A

Just lateral to tendon of EHL

96
Q

In the dorsum of the foot, where does the dorsalis pedis artery divide?

A

at the proximal part of the first intermetatarsal space, where it divides into two branches, the first dorsal metatarsal artery and the deep plantar artery.

97
Q

What does the deep plantar artery go on to anastamose with?

A

Travels deep into the foot and anastamoses with branches of the plantar aspect (medial and lateral plantar arteries)

98
Q

This 35 year old man presented to the ED with pain in his second toe after accidentally kicking something.

Can you describe the injury?

A
  • Fracture of the proximal phalanx of the 2nd toe
99
Q

What is a sesamoid bone?

A

A sesamoid bone is a bone that is inside a tendon where the tendon passes over a joint (e.g. patella)

Can be seen in this xray in big toe

100
Q

This 40 year old man presented with on-going pain after a heavy object fell onto his left foot several days ago.

Can you describe the injury?

A
  • 3rd metatarsal oblique fracture
101
Q

This 60 year old woman presented to her GP with chronic pain in the medial side of her left foot for over 1 year. There was no history of trauma. Her foot appeared normal on examination, but was tender on the medial aspect.

Can you see anything that would explain the patient’s pain?

A
  • A foreign body –> very white line (radiopaque)
    • A thin metallic object in the foot
102
Q

An man was taken to hospital by his daughter, who was concerned about swelling and deformity in his right foot.

The patient’s foot wasn’t painful, and was not tender on examination, but it was clearly very swollen.

The patient’s PMH included a diagnosis of leprosy many years ago.

  • What is the term for this abnormality?
  • Why isn’t the patient’s foot painful?
  • What is the cause of this abnormality in this patient?
A
  • Not painful as a result of peripheral neuropathy
    • Limited sensation in the foot
  • Appearance of foot in x-ray: Charcot joint (often Charcot foot)
    • Progressive degeneration of a weight bearing joint, a process marked by bony destruction, bone resorption, and eventual deformity due to loss of sensation
103
Q

What is Charcot foot?

A

The progressive degeneration of a weight bearing joint, a process marked by bony destruction, bone resorption, and eventual deformity due to loss of sensation

104
Q

What other disease, except leprosy, can lead to Charcot’s foot?

A

Diabetes (uncontrolled)