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Flashcards in Gross Anatomy Deck (261)
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1
Q

What is the role of dendrites?

A

Increase surface area

Communicate with adjacent neurones

2
Q

What is the role of myelin sheath?

A

Coat axons to help speed up action potentials

3
Q

What is the myelin sheath produced by in the PNS versus the CNS?

A

Shwann cells

Oligodendrocyte

4
Q

What are the two types of neurones?

A

Multipolar - 2 or more dendrites and cell body in CNS

Unipolar - double process (pseudounipolar) and cell body in PNS

5
Q

What neurones are classed as multipolar?

A

All motor neurones of SkM and ANS (pre-synaptic)

6
Q

What neurones are classed as unipolar?

A

Sensory post-synaptic neurones in the ANS

7
Q

In what direction do efferent impulses move?

A

MOTOR - Exits brain and moves towards body wall, cavity or organ

8
Q

In what direction do afferent impulses move?

A

SENSORY - impulse Arrives at brain

9
Q

What is a nerve? What is this referred to in the CNS?

A

Collection of axons surrounded by CT and blood vessels

Tract

10
Q

What are the two types of nerves?

A

Single modality - one of somatic motor/ sensory, special sensory, sympathetic, parasympathetic or visceral afferent

Mixed modality - somatic motor, somatic sensory and sympathetic all in one nerve

11
Q

A tract is most likely to be single modality. True/ False?

A

True

12
Q

Give the first cranial nerve, it’s modality, function and foramen

A

1 (CNI) Olfactory - Cribiform plate (Forebrain) - Sensory (special) - Smell

13
Q

Give the second cranial nerve, it’s modality, function and foramen

A

2 (CNII) Optic - Optic canal (Forebrain) Sensory (special) - Vision

14
Q

Give the third cranial nerve, it’s modality, function and foramen

A

3 (CNIII) Oculomotor - Superior orbital fissure (Midbrain) -Motor - 4 extrinsic eye muscles and levator palpebrae superioris
- PS - pupillary sphincter

15
Q

Give the fourth cranial nerve, it’s modality, function and foramen

A

4 (CNIV) Trochlear - Superior orbital fissure (Midbrain) Motor - Superior oblique

16
Q

Give the fifth cranial nerve, it’s modality, function and foramen

A

5 (CNV) Trigeminal: PONS
Ophthalmic - Superior orbital fissure - Sensory - Scalp, forehead and nose.
Maxillary - F. rotundum - Sensory - Cheeks, lower eye lid, nasal mucosa, upper lip, upper teeth and palate.
Mandibular - F. ovale

Sensory - anterior 2/3 tongue, skin over mandible and lower teeth.
Motor: muscles of mastication

17
Q

Give the sixth cranial nerve, it’s modality, function and foramen

A

6 (CNVI) Abducens - Superior orbital fissure (Junction between pons and medulla) - Motor - Lateral rectus

18
Q

Give the seventh cranial nerve, it’s modality, function and foramen

A

7 (CNVII) Facial - Internal acoustic meatus > stylomastoid f. (Junction between pons and medulla) - Both - Sensory (special): sensation to part of ext. ear., taste from ant. 2/3 tongue, hard and soft palate., muscles of facial expression.
Motor and PS: lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose.

19
Q

Give the eighth cranial nerve, it’s modality, function and foramen

A

8 (CNVIII) Vestibulocochlear - Internal acoustic meatus - (Junction between pons and medulla) - Sensory (special) - Hearing and balance

20
Q

Give the ninth cranial nerve, it’s modality, function and foramen

A

9 (CNIX) Glossopharyngeal - Jugular f. (Medulla) - Both:

Sensory: post. 1/3 tongue, nasopharynx, oropharynx, laryngopharynx, palatine tonsil, eustachian tube, ext. ear, and middle ear cavity.,
Special sensory: taste from post. 1/3 tongue(vallate papillae)
VA: carotid sinus receptors and carotid body
Motor: stylopharyngeus
PS: to parotid gland

21
Q

Give the tenth cranial nerve, it’s modality, function and foramen

A

10 (CNX) Vagus - Jugular f. (Medulla) - Both:

Sensory: ext. ear, larynx and pharynx., larynx, pharynx and, thoracic & abdominal viscera., taste from epiglottis region of tongue
Motor and PS: smooth muscles of pharynx, larynx and most of the GIT

22
Q

Give the eleventh cranial nerve, it’s modality, function and foramen

A

11 (CNXI) Spinal accessory - Jugular f. (Spinal cord) Motor: trapezius and sternocleidomastoid., a few fibres run with CNX to viscera.

23
Q

Give the twelth cranial nerve, it’s modality, function and foramen

A

12 (CNXII) Hypoglossal - Hypoglossal canal (Medulla) Motor: Intrinsic and extrinsic tongue muscles (except the palatoglossus).`

24
Q

There are 31 pairs of spinal nerves, how are they divided in the spinal cord?

A
Cervical (C1 - C8)
Thoracic (T1 - T12)
Lumbar (L1 - L5)
Sacral (S1 - S5)
Coccygeal (Co1)
25
Q

There are 8 cervical spinal nerves, but how many vertebrae are there?

A

7

26
Q

Where are spinal nerves found at the vertebrae, and what do they branch into?

A

Intervertebral foramina

Anterior (supply larger anterolateral body wall) and posterior ramus (smaller posterior wall)

27
Q

What is the route taken by all sensory axons to the horn of the spinal cord?

A

Posterior root –> rootlets —> horn

28
Q

What is the route taken by all motor axons to the spinal nerve?

A

Anterior horn of the spinal cord –> rootlets –> root –> spinal nerve

29
Q

What is the function of the dorsal root ganglion?

A

Location of cell bodies of primary afferent neurones

30
Q

Roots/rootlets are ____ modality and ramii are ____ modality

A

Single

Mixed

31
Q

What three types of nerve supply does a spinal nerve supply to unilateral area of the body?

A

General sensory to all structures
Somatic motor to skeletal muscle
Sympathetic to skin and smooth muscle of arterioles
NOT PARASYMPATHETIC

32
Q

What is a dermatome?

A

Area of skin supplied with sensory innervation from a single spinal nerve

33
Q

What is a myotome?

A

SkM supplied with motor innvervation from single spinal nerve

34
Q

In the dermatome map, what level is the male nipple at?

A

T4

35
Q

In the dermatome map, what level is the umbilicus at?

A

T10

36
Q

In the dermatome map, what level is the posterior scalp, neck and shoulder at?

A

C2-C4

37
Q

In the dermatome map, what level is the upper limb at?

A

C5-T1

38
Q

In the dermatome map, what level is the lower limb, gluteal region, perineum at?

A

L2-Co1

39
Q

What is a nerve plexus?

A

Intermingled anterior rami from a number of adjacent spinal nerves

40
Q

What levels is the cervical plexus, and what does it supply?

A

C1-C4

Posterior scalp, neck and diaphragm

41
Q

What levels is the brachial plexus, and what does it supply?

A

C5-T1

Upper limb

42
Q

What levels is the lumbar plexus, and what does it supply?

A

L1-L4

Lower limb

43
Q

What levels is the sacral plexus, and what does it supply?

A

L5-S4

Lower limb, gluteal region, perineum

44
Q

Sympathetic outflow from the brain enters the spinal cord at what levels? What is this known as?

A

T1 - L2

Thoracolumbar outflow

45
Q

What is the route taken by sympathetic nerves to the area it is supplying?

A

Lateral horns of T1-L2 —> sympathetic chain —> spinal nerves —> anterior and posterior rami —> hitch a ride with arteries —> supply sweat glands, skin arrectors, arterioles

46
Q

What are the four nerve routes taken by sympathetic outflow in all spinal nerves?

A

Heart
Lungs
Abdomniopelvic organs
Adrenal medulla

47
Q

What allows a sympathetic axon to pass onto a paravertebral ganglion of the sympathetic trunk?

A

Rami communicans

48
Q

Where do sympathetic presynaptic axons in the heart synapse?

A

Synapse in T1 or cervical paravertebral ganglia

49
Q

What is the route taken by sympathetic postsynaptic axons in the heart?

A

Pass in cardiopulmonary splanchic nerves to the SA and AV nodes and myocardium

50
Q

Where do sympathetic presynaptic axons in the lungs synapse?

A

Synapse in upper thoracic paravertebral ganglia

51
Q

What is the route taken by sympathetic postsynaptic axons in the lungs?

A

Pass in cardiopulmonary splanchic nerves to bronchiolar SM and mucous glands

52
Q

Where do sympathetic presynaptic axons of the abdominopelvic organs synapse?

A

In one of the prevertebral ganglia

53
Q

List the sympathetic prevertebral ganglion associated with abdominopelvic organs for the foregut, midgut and hindgut respectively

A

Celiac ganglion of celiac plexus (FOREGUT)
Superior mesenteric ganglion of SM plexus (MIDGUT)
Inferior mesenteric ganglion of IF plexus (HINDGUT AND PELVIC/PERINEAL ORGANS)

54
Q

List the sympathetic prevertebral ganglion associated with abdominopelvic organs, in this case for the kidney

A

Aorticorenal ganglion

55
Q

Where are these sympathetic prevertebral ganglion located anatomically?

A

At named artery as it branches from the abdominal aorta

56
Q

What is the route taken by presynaptic sympathetic axons to reach the adrenal medulla?

A

Pass through aorticorenal ganglion

Synapse DIRECTLY onto adrenaline/ NA secreting cells of the adrenal medulla

57
Q

How do presynaptic axons of parasympathetic outflow leave the CNS? What is this known as?

A

Via CN III, VII, IX, X and sacral spinal nerves

Craniosacral outflow

58
Q

What do presynaptic parasympathetic axons travel on to reach the eye?

A

Ciliary ganglion

59
Q

What do presynaptic parasympathetic axons travel on to reach the lacrimal and salivary glands?

A

Parasympathetic ganglia in the head

60
Q

What do presynaptic parasympathetic axons travel on to reach the organs of the head, neck, chest and abdomen as far as the midgut?

A

Vagus nerve

61
Q

What do presynaptic parasympathetic axons travel on to reach the hindgut, pelvis and perineum?

A

Sacral spinal nerves

62
Q

What is a classical clinical example of impaired sympathetic innervation to head and neck?

A

Horner’s syndrome

63
Q

What are the symptoms of Horner’s syndrome?

A

Miosis
Ptosis
Reduced sweating (anhydrosis)
Increased warmth and redness

64
Q

What are the causes of compression of the cervical parts of the sympathetic trunk in Horner’s syndrome?

A
Root of neck trauma 
Carotid dissection
Internal jugular vein engorgement
Deep cervical node metastases
Pancoast tumour (lung apex)
65
Q

What vertebrae can be palpated first on the back?

A

T1 spinous process

66
Q

What do skin dimples on the lower back represent?

A

PSIS

67
Q

What are the three parts of the trapezius, relative to their position on the back?

A

Descending (superior)
Transverse (middle)
Ascending (inferior)

68
Q

Which rotator cuff muscle can be palpated on the back?

A

Teres major

69
Q

Which muscle may be affected in lower back pain?

A

Erector spinae

70
Q

What are the extrinsic back muscles (top - bottom), and what do they attach to?

A
Levator scapulae
Rhomboid major and minor
Trapezius
Latissimus dorsi
PECTORAL GIRDLE
71
Q

What is the function of the extrinsic back muscles?

A

Move upper limb

72
Q

What is the function of the intrinsic back muscles?

A

Maintain posture and extend the spine (ES) or rotate the spine (TVSPS)

73
Q

What is the main superficial intrinsic back muscle? Where does it attach inferiorly?

A

Erector spinae

Common tendon to sacrum and iliac crest

74
Q

What are the divisions of the erector spinae, and thus where do they attach superiorly?

A

Rib (Costalis)
Transverse process of vertebra (Longus)
Spinous process of vertebra (Spinous)

75
Q

What is the main deep intrinsic back muscle? Where is it located?

A

Transversospinalis

Within grooves between transverse and spinous processes

76
Q

Where do the muscle fibres of transversospinalis attach between?

A

Vertebra and skull
Vertebra and rib
One vertebra and another
Sacrum and vertebra

77
Q

What is the nerve supply to the back muscles?

A

Segmental (as per dermatome/ myotome)

Via posterior ramii branches (cervical , thoracic, lumbar)

78
Q

What muscles lie laterally to the vertebral column?

A

MUSCLES OF POSTERIOR ABDO WALL
Psoas major
Quadratus lomborum

79
Q

What muscles lie posterally to the vertebral column?

A

INTRINSIC BACK MUSCLES
Transversospinalis
Erector spinae

80
Q

What muscles lie laterally to the posterior abdominal wall muscles?

A
MUSCLE OF UL
Latissimus dorsi
MUSCLES OF ANTEROLATERAL ABDO WALL
Transverse abdominus
Internal oblique
External oblique
81
Q

If the erector spinae muscle contracts bilaterally the spine will undergo…

A

Extension

82
Q

If the erector spinae muscle contracts unilaterally the spine will undergo …

A

Lateral flexion

83
Q

What muscles control flexion of the spine?

A

Rectus abdominus

Psoas major

84
Q

How many vertebrae are there in the adult vertebral column?

A

33

85
Q

How are the vertebrae divided?

A
7 cervical (C1 - C8)
12 thoracic (T1 - T12)
5 lumbar (L1 - L5)
5 sacral (1 sacrum)
4 coccygeal (1 coccyx)
86
Q

What are the 3 functions of the vertebrae?

A

Support head and trunk when upright
Protect spinal cord and nerves
Allow movement of head on neck and trunk

87
Q

What are the main curvatures of the spine and are they primary or secondary?

A
Cervical lordosis (2)
Lumbar lordosis (2)
Thoracic kyphosis (1)
Sacral kyphosis (1)
88
Q

What curvature pathology is caused by excessive anterior weight e.g. in pregnancy or obesity?

A

Excessive lumbar lordosis

89
Q

What curvature pathology is caused by old age typically?

A

Excessive thoracic kyphosis

90
Q

List the parts of a vertebra

A

Spinous process x 1
Transverse process x 2
Inferior and superior articular processes x 4
Vertebral foramen
Vertebral body
Vertebral arch (made up of 2 x pedicle (superior) and 2 x lamina)

91
Q

What type of joint is the articulation between articular processes and adjacent vertebrae?

A

Synovial facet joint

92
Q

Which structure contains and protects the spinal cord and nerves?

A

Intervertebral foramen

93
Q

What joints are affected in arthritis of the spine?

A

Facet joint

94
Q

Where are IV discs found? What are they at risk of?

A

Between adjacent vertebral bodies

Disc herniation

95
Q

Where is there an abscence of IV discs?

A

Between C1 and C2

96
Q

Describe the structure of an IV disc

A

Outer fibrous ring - annulus fibrosis

Inner soft pulp - nucleus pulposis

97
Q

Which short ligament connects the adjacent lamina posteriorly to the spinal cord?

A

Ligamentum flavum

98
Q

What is the function of the posterior longitudinal ligament?

A

Narrow and weak

Prevents overflexion

99
Q

What is the function of the anterior longitudinal ligament?

A

Broad and strong

Prevents overextension

100
Q

What is the function of the supraspinous ligaments?

A

Strong, fibrous

Connects tips of spinous processes

101
Q

What is the function of the interspinous ligaments?

A

Weak, membranous

Connect superior and inferior parts of adjacent spinous processes

102
Q

List the ligaments of the vertebral column

A
Ligamentum flavum
Posterior longitudinal ligament
Anterior longitudinal ligament
Supraspinous ligaments
Interspinous ligaments
103
Q

Which vertebra are classed as atypical and why?

A

C1: ATLAS - no body or spinous process - A + P arch instead
C2: AXIS - odontoid process, which projects superiorly from body
C7: VERTEBRA PROMINENS - 1st palpable spinous process

104
Q

Which ligament connects C1 and C2 vertebra?

A

Transverse ligament

105
Q

Where does the atlanto-occipital joint connect?

A

Between occipital condyles of C1 and superior articular facets of atlas

106
Q

What type of joint is the atlanto-occipital joint? What is it’s function?

A

Synovial joint
Flexion and extension of neck (yes, no)
Some lateral flexion and rotation

107
Q

Where does the atlanto-axial joint connect?

A

3 articulations
2 x inferior articular facets of atlas and superior articular facets of axis
1 x anterior arch of atlas and odontoid process of axis

108
Q

What is the main role of the atlanto-axial joint?

A

Rotation

109
Q

What are the names given to the area at the top and bottom of the sacral canal?

A

Sacral promontory

Sacral hiatus

110
Q

What are commonly classed as the ‘wings’ of the sacrum?

A

Left and right ala

111
Q

What exists within the sacral canal?

A

Cauda equina

Meninges

112
Q

Which part of the sacrum is palpable?

A

Sacral hiatus

113
Q

Which part of the sacrum is caudal anaesthesia inserted into to anaesthetise sacral spinal roots?

A

Sacral hiatus

114
Q

Where does the spinal cord start and end?

A
Foramen magnum (C1)
Vertebral level L1/L2 (Co1 segment)
115
Q

What is the cauda equina?

A

All spinal nerve routes from L2 to Co that have descended to numbered vertebra where the spinal nerve is in IV foramen

116
Q

What is the spinal cord surrounded by?

A
3 layers of meninges (dura, arachnoid matter, pia)
Epidural fat (and venous plexuses)
117
Q

What is a laminectomy?

A

Removal of 1 or more spinous processes and adjacent lamina to relieve pressure on the spinal cord/ nerve roots

118
Q

What type of receptors exist in all body wall structures for somatic general senosry spinal nerves. List some examples

A

Sensation specific receptors

Pain, touch, temperature, proprioception, vibration

119
Q

What type of fibres do somatic motor axons on spinal nerves synapse onto on the body wall?

A

Skeletal muscle

120
Q

What type of fibres do sympathetic axons on spinal nerves synapse onto?

A

Smooth muscle

121
Q

What fibres does the spinal cord segmental synapse between for spinal reflexes?

A

Somatic sensory and somatic motor axons

122
Q

Describe the types of general sensory somatic symptoms that the body wall percieves

A
Pain (neuralgia)
Pins and needles (paraesthesia)
Numbness (anaesthesia)
Sensitivity (hyperanaesthesia)
Hot or cold
Loss of coordination/ balance/ clumsiness (ataxia)
123
Q

Describe the types of somatic motor symptoms that the body wall percieves

A

Muscle stiffness, tightness or spasm (cramp)
Muscle flappiness or looseness (hypotonia)
Muscular weakness (reduced power)
Loss of coordination/ balance/ clumsiness (ataxia)

124
Q

What are the neural components of the body wall?

A

Somatic general sensory fibres
Somatic motor fibres
Sympathetic fibres (motor to organs)
Spinal reflexes

125
Q

What is used to test sensory function of spinal nerves?

A

Dermatomes

126
Q

What is used to test motor function of spinal nerves?

A

Myotomes

127
Q

In what situation, would we test both motor and sensory function of spinal nerves?

A

Spinal reflexes

128
Q

What area of the brain is common for CVA?

A

Internal capsule

129
Q

Identify the dermatomal locations of the cervical roots in the upper limb

A

C1: SN has no sensory axons
C2: Back of scalp and Adams apple (area that looks like a helmet with a strap tied below the chin)
C4: Clavicle and shoulder tip (neck lace)
C3: Back of neck and jugular notch (area between C2 and 4)
C5: ‘Badge patch’ (anterior chest and continues to wrist) WE DIVE TO T1 (most of arm)
C6: Thumb (+ index finger, if you join together they make 6) and lateral posterior arm
C7: Index and middle finger (continuation) and middle posterior forearm
C8: Ring and little finger (continuation) and medial posterior forearm

130
Q

Identify the dermatomal locations of the thoracic roots in the upper limb and trunk

A
Entire area makes the letter T
T1: Medial forearm (limbs are topmost )
T2: Medial arm and sternal angle
T4: Male nipple ('boob')
T10: Umbilicus (bell butTEN)
T12: Pubic symphysis
131
Q

Identify the dermatomal locations of the lumbar roots in the pelvis and lower limb

A

Supplies legs and loin
L1: Groin ‘hands in pockets’ (1nguinaL area)
L2: Anterior thigh
L3: Anterior thigh
L4: KNEE (to medial malleolus) (down on L4s) and great toe (great ‘fire’ of London)
L5: Dorsum of foot (middle part of sole is triangle like an inverted V (roman for 5)

132
Q

Identify the dermatomal locations of the sacral roots in the lower limb

A

Concentric fashion (out to in)
S1: Heel (POSTERIOR LEG)
S2: Posterior knee (lateral leg and foot inc. little toe) (FREE INC, GENITAL AREA)

(BULLSEYE OF ANUS)
S3: Buttock (FREE INC. GENITAL AREA)
S4: Perineum
S5: Perianal skin (anus)

133
Q

What is the sensory area supplied by the posterior ramii, allowing us to test these ramii?

A

Supply a strip of skin centrally down back and posterior neck (C2 - C8 spinal nerves)

134
Q

How would we test the sensory component of the anterior ramii?

A

Forms plexuses - cervical, brachial, lumbar, sacral which can be tested

135
Q

Which spinal cord levels do not contribute to anterior ramii?

A

T2 - T12

136
Q

Which nerves are formed from the bifurcation of L1?

A

Ilioinguinal and iliohypogastric

137
Q

Which nerves are formed from the anterior ramii of T2 - T11?

A

Intercostal nerves

138
Q

Which nerve is formed from the anterior ramii of T12?

A

Subcostal nerve

139
Q

What is the difference between a spinal nerve and a named nerve?

A

Spinal nerves are axons originating from one spinal cord level e.g. L5 spinal nerve, whereas named nerve are axons originating from 1 or more spinal cord levels supplying an area e.g. musculocutaneous nerve (C5, 6, 7)

140
Q

Identify the plexus and list the nerve roots giving rise to the named nerve cutaneous innervation of the neck

A

CERVICAL PLEXUS

Anterior ramii of C1, 2, 3, 4

141
Q

Identify the specific sensory nerves and roots which form the named nerve cutaneous innervation of the neck

A

CERVICAL PLEXUS
LITTLE GOATS TRED SOFTLY:
Starting from -
11 o’clock: Lesser occipital nerve (C2) - posterior to external ear
1 o’clock: Great auricular nerve (C2, 3) - angle of mandible and external ear
3 o’clock: Trasverse cervical nerve (C2, 3) - anterior neck
6 o’clock: Supraclavicular (C3, 4) - clavicle, shoulder pain

142
Q

What is the nerve point?

A

Point at which sensory nerves of cervical plexus converge

143
Q

Which sensory nerve is involved in referral of pain from the diaphragm?

A

Supraclavicular nerve (C3, 4)

144
Q

Which nerve roots are important in referred pain from the myocardium?

A

T1, T2

145
Q

What supplies the anatomical snuffbox?

A

Cutaneous branches of the radial nerve

146
Q

Identify the specific sensory nerves and roots that form the named nerve cutaneous innervation of the upper limb

A

BRACHIAL PLEXUS
Shoulder - middle finger (lateral) and back up (medial)

Supraclavicular (C3,4) - Shoulder
Axillary nerve (C5, 6) - Badge patch area
Radial nerve (C5, 6, 7, 8, T1) - Lateral arm (and most of posterior)
Cutaneous branch of musculocutaneous (C5, 6, 7) - Lateral half of anterior forearm (and a bit posterior)
Radial nerve (Lateral hand - snuffbox)
Median nerve (C5, 6, 7, 8, T1) - Lateral 3 1/2 digits (and posterior fingertips of these fingers)
Ulnar nerve (C7, C8, T1) - Medial 1 1/2 fingers (and these fingers posteriorly)
Median antebrachial cutaneous nerve

147
Q

Identify the sensory nerves of the lumbosacral plexus that form the named nerve cutaneous innervation of the ANTERIOR lower limb

A
1ST LAYER: lateral to medial
Subcostal nerve (T12) - corner
Genitofemoral nerve (L1, L2) - 1 or 2 balls
Ilioinguinal nerve (L1) - 1lioinguinaL

2ND LAYER: lateral to medial
Lateral cutaneous nerve of the thigh (L3, L4)
Femoral nerve (L2, L3, L4) - FRONT
Obturator nerve (L2, L3, L4) - OPEN YOUR LEGS

3RD LAYER: lateral to medial
Common fibular nerve (L2, L3) - TELLING A FIB - HIDING SOMETHING
Saphenous nerve (L3, L4) - from femoral - SECRET

4TH LAYER: lateral to medial
Sural nerve (S1, S2) - ‘sweet’ little toe
Superficial fibular nerve (L4, L5, S1) - shoe (most of foot)
Deep fibular nerve (L5) - ‘fin’ - toe web

148
Q

Identify the sensory nerves of the lumbosacral plexus that form the named nerve cutaneous innervation of the POSTERIOR lower limb

A

1ST LAYER: lateral to medial
Iliohypogastric nerve (L1) - ‘1Lio’
Posterior ramii (cluneal nerves) (S1, S2, S3) - ‘No clue = hiding at back)
Ilioinguinal nerve

2ND LAYER: lateral to medial
Lateral cutaneous nerve of thigh
Posterior cutaneous nerve of thigh (S1, S2, S3)
Obturator and femoral nerves

3RD LAYER: lateral to medial
Common fibular nerve
Sural nerve (from tibial and common fibular: S1, S2 - SECRET (in middle)
Saphenous nerve

4TH LAYER: lateral to medial
Tibial nerve (L4, L5, S1, S2, S3)
Calcaneal nerve (HEEL)
Medial and lateral plantar nerves (SOLE)

149
Q

Describe the route of a somato-sensory action potential from the skin to the somatosensory cortex

A

Stimulated nerve
AP generated by receptors in L2 dermatome
AP enters lumbar plexus and reaches L2 anterior ramii
AP continues to L2 spinal nerve, then posterior root and rootlets
AP reaches posterior horn of spinal cord

150
Q

Identify the myotomes supplied by the cervical plexus

A

C1 - C4 motor axons - neck and strap muscles, diaphragm

151
Q

Identify the myotomes supplied by the brachial plexus

A

C5 - T1 motor axons - muscles of upper limb, extrinsic back muscles (control upper limb and scapula)

152
Q

Identify the myotomes supplied by the lumbosacral plexus

A

L1 - S4 motor axons - muscles of lower limb, perineal skeletal muscle

153
Q

Identify the myotomes supplied by T12 - L3 motor axons

A
Postural back muscles (posterior ramii)
Intercostal muscles (anterior ramii)
AL abdominal wall muscles (via thoracoabdominal, subcostal, iliohypogastric, ilioinguinal)
154
Q

How do you clinically test the C5 motor axons, supplying a myotome? What muscle are you testing?

A
Shoulder ABD (also elbow flexion)
Deltoid
155
Q

How do you clinically test the C6 motor axons, supplying a myotome? What muscle are you testing?

A

Wrist EXT

Biceps brachii

156
Q

How do you clinically test the C7 motor axons, supplying a myotome? What muscle are you testing?

A

Elbow EXT

Triceps brachii

157
Q

How do you clinically test the C8 motor axons, supplying a myotome? What muscle are you testing?

A

Finger FLEX

Flexor digitorium superficialis

158
Q

How do you clinically test the T1 motor axons, supplying a myotome? What muscle are you testing?

A

Finger ABD

Dorsal interossei

159
Q

How do you clinically test the L3 motor axons, supplying a myotome? What muscle are you testing?

A

Knee EXT

Quadriceps femoris

160
Q

How do you clinically test the L4 motor axons, supplying a myotome? What muscle are you testing?

A

Ankle DF

Tibialis anterior

161
Q

How do you clinically test the L5 motor axons, supplying a myotome? What muscle are you testing?

A

Great toe EXT

Extensor hallucis longis

162
Q

How do you clinically test the S1 motor axons, supplying a myotome? What muscle are you testing?

A

Ankle PF

Gastrocneumius

163
Q

How do you clinically test the S2 motor axons, supplying a myotome? What muscle are you testing?

A

Knee FLEX

Biceps femoris

164
Q

Describe the route of a somato-motor action potential from the primary somatomotor cortex (UMN) to skeletal muscle.

A

Primary somatosensory cortex
AP continues onto UMN axons of CST
AP continues onto anterior horn of L3 spinal cord
UMN synapse with L3 LMN
AP continues to L3 spinal nerve
AP continues onto L3 posterior or anterior ramus
AP enters the lumbar plexus of named nerve and reaches NMJ of supplied nerve

165
Q

What is a reflex? Describe the patellar reflex

A

Involuntary response to stimulus

Patella senses stretch, activates APs in femoral nerves and sensory APs to dorsal horn of L3 axons
Axons synapse on LMNs in femoral nerve
Reach quadriceps NMJ and extension occurs

166
Q

What is a monosynaptic reflex? What does it indicated?

A

Occurs each time a skeletal muscle is stretched

Normal muscle tone

167
Q

Reflex muscle contractions are controlled by…

A

Descending pathways

168
Q

What sign would suggest an UMN lesions versus a LMN lesion?

A

Spasticity

Flaccidity

169
Q

Which axons are activated when testing the tendon jerk of biceps brachii?

A

C5, C6

170
Q

Which axons are activated when testing the tendon jerk of brachioradialis?

A

C6

171
Q

Which axons are activated when testing the tendon jerk of triceps brachii?

A

C7, C8

172
Q

Which axons are activated when testing the knee jerk reflex?

A

L3, L4

173
Q

Which axons are activated when testing the ankle jerk reflex?

A

S1, S2

174
Q

Anterior roots contain only sensory/motor axons, whilst posterior roots contain only sensory/ motor axons?

A

Motor

Sensory

175
Q

The space in the middle of the grey matter in the spinal cord is known as the?

A

Spinal canal

176
Q

For CNI, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

In olfactory mucosa in nasal cavity
Synapse in olfactory bulb, and pass to olfactory tract
NO CONNECTION

177
Q

Outline how you would go about testing CNI

A

Smell while covering contralateral side

178
Q

For CNII, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Neurones of retina travel posteriorly via optic nerve to the orbit
Pass from the optic chiasm to the optic tract
Diencephalon

179
Q

Outline how you would go about testing CNII

A
Visual acuity (Snellen)
Colour (Ishihara plates)
Fields (4 quadrants)
Reflexes (Pupillary light reflexes)
Fundoscopy
180
Q

For CNIII, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

SOF into orbit and supply all extraocular muscles except 2, PSs synapse in ciliary ganglion
Lateral wall of cavernous sinus (orbit)
Mesencephalon (midbrain)

181
Q

Outline how you would go about testing CNIII

A

Light reflexes via a torch (PS)

182
Q

For CNIV, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

SOF into orbit and supply SO muscle
Lateral wall of cavernous sinus (orbit)
Mesencephalon (midbrain)

183
Q

Outline how you would go about testing CNIV

A

H test (in and down)

184
Q

For CNVI, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

SOF into orbit and supply LR muscle
Cavernous sinus to orbit
Pontomedullary junction

185
Q

Outline how you would go about testing CNVI

A

H test (out)

186
Q

For CNVIII, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Axons from cochlear and vestibular apparatus
Posteromedially from IAM to PM junction
Pontomedullary junction

187
Q

Outline how you would go about testing CNVIII

A

Rinnie and Weber tests

188
Q

For CNXI, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Axons supply SCMD, travel across posterior triangle to trapezius
Foramen magnum to jugular foramen
Cervical spinal cord

189
Q

Outline how you would go about testing CNXI

A
Shrug shoulders (and resist) - TRAPEZIUS
Turn head to flex neck (and resist) - SCMD
190
Q

For CNXII, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Descends lateral to carotid sheath (at hyoid turns anteriorly to tongue)
Pass anteriorly to hypoglossal canal
Many rootlets lateral to pyramids of medulla

191
Q

Outline how you would go about testing CNXII

A

Stick tongue out and move side-side

Tip of tongue will point towards side of pathology

192
Q

For CNV, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Sensory passes superficial to deep structures of face posteriorly to foramen
Motor from CNV3 travels from f. ovale to skeletal muscle

Inferior to tentorium cerebelli

Pons!

193
Q

Give the superficial sensory divisions for the trigeminal supply to the face

A

CNVI: upper eyelid to tip of nose to forehead
CNV2: Lower eyelid to upper lip and nostril
CNV3: Lower lip and chin to TMJ/ mandible (except angle)

194
Q

What gives sensory supply to the angle of mandible, and what are the roots of this nerve?

A

Great auricular nerve (C2, C3)

195
Q

Give the deep sensory divisions for the trigeminal supply to the face

A

CNV1: orbit (not floor or lower eyelid), upper anterior nasal cavity, paranasal sinuses (not maxillary), anterior and posterior CF

CNV2: lower posterior nasal cavity, maxillary sinus, maxilla, floor of nasal cavity/ palate, maxillary teeth, soft tissues

CNV3: Middle CF, mandible A 2/3 of tongue, floor of mouth, buccal mucosa, mandibular teeth

196
Q

Outline how you would go about testing the sensory divisons of CNV

A

Close eyes
Cotton wool - ‘Say when you feel me touching you’
Compare sides

197
Q

Which nerve is the 1st part of afferent limb of blink/ corneal reflex?

A

Long ciliary nerve

198
Q

Outline how you would go about testing the motor division of CNX

A

Palpate strength of masseter (clench teeth)

Open jaw against resistance

199
Q

For CNVII, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Somatic motor fibres to parotid gland and then facial expression muscles (1 out of 5)
Directly to IAM
Pontomedullary junction

200
Q

The facial canal is located within what part of the temporal bone?

A

Petrous part

201
Q

What is the function of chorda tympani, a branch of CNVII?

A

Taste to A 2/3 of tongue

PS to submandibular and sublingual glands (salvation)

202
Q

What is the tiniest SkM in the body?

A

Stapedius

203
Q

What is the role of the stapedius muscle, and what happens when you damage it?

A

Reduces stapes movement to dampen down excessive noise

Hyperacuisis

204
Q

Outline how you would go about testing CNVII

A

Test the muscles of facial expression - raise eyebrows, close eyes tightly, smile, puff out cheeks and hold air

205
Q

List the muscles of facial expression

A

Frontalis
Orbicularis oculi
Elevators of lips
Orbicularis oris

206
Q

For CNIX, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Descends in pharynx in mouth to stylopharyngeus, parotid gland, pharyngeal muscosa, carotid body and sinus, posterior 1/3 of tongue

Directly to jugular foramen

Medulla oblongata

207
Q

Outline how you would go about testing CNIX

A

Elicit afferent limb of gag reflex

208
Q

What is the only muscle supplied by CNIX

A

Stylopharyngeus

209
Q

Which muscles are supplied with motor innervation from CNV?

A

Tensor tympani
Tensor veli palatini
1 pair of jaw closing muscles - lateral pterygoid
3 pairs of jaw opening muscles - masseter, temporalis, medial pterygoid

210
Q

For CNX, give it’s extracranial and intracranial course and connection with CNS (if applicable)

A

Structures between pallate and midgut
Directly into jugular foramen
Medulla oblongata

211
Q

Why is pain often referred from pharynx to ear and vice versa?

A

Both supplied by glosopharyngeal nerve

212
Q

What two vessels is the carotid sheath located between?

A

CCA and IJV

213
Q

The left recurrent laryngeal nerve, branch of CNX, passes under…

A

Arch of aorta

214
Q

The right recurrent laryngeal nerve, branch of CNX, passes under…

A

Right subclavian artery

215
Q

Outline the route taken by both vagus nerves from the chest to abdomen

A
RIGHT: Lateral aspect of trachea
LEFT: Lateral aspect of aortic arch
Pass posterior to lung root on oesophagus
Pass through diaphragm with oesophagus
Pass onto surface of stomach
Branches and travels to organs
216
Q

List the branches of the vagus nerve in the abdomen

A
Celiac and superior mesenteric ganglia
Foregut
Renal
Midgut (on mesenteries)
Splenic
Pancreatic
217
Q

What vertebral level do the oesophagus and vagus nerve pass through the diaphragm?

A

T10

218
Q

Where do the vagus nerves very last PS axons pass onto?

A

Splenic flexure of colon

219
Q

Outline how you would go about testing CNX

A

MUSCLES OF PALATE (motor) - Say ‘aaah’ - uvula deviates to side that is functioning
PHARYNGEAL MUSCLES - Swallow water and see if they splutter
LARYNGEAL MUSCLES - Listen to speech and see if any hoarseness

220
Q

What is a space-occupying lesion, and what are the two main types?

A

Abnormal tissue taking up space

Acute or subacute

221
Q

What are the layers of the scalp?

A
SCALP
Skin
CT (artery-rich)
Aponeurosis (tendon)
Loose CT (thinnest)
Pericranium (periostum - outer membrane of bone)
222
Q

Why do scalp lacerations and incisions bleed excessively?

A

Scalp arteries form a rich anastomotic network just deep to skin

223
Q

What two arteries do scalp arteries branch from?

A

Internal and external carotid

224
Q

What is the thinnest part of the skull? What type of joint is it? What artery courses just deep to it?

A

Pterion
Fibrous joint - suture (H shape)
Middle meningeal artery

225
Q

List the borders of each of the cranial fossa; anterior, middle and posterior?

A

Frontal bone - wings of sphenoid
WIngs of sphenoid - petrous temporal bone
Petrous temporal bone - occipital bone

226
Q

What is the name for the protective coverings of the brain and spinal cord?

A

Meninges

227
Q

List the 3 layers of membrane covering the brain and spinal cord, from superficial to deep

A

Dura matter ‘hard matter’ (ADHERENT TO SKULL)
Arachnoid matter ‘spidery mother’
(Subarachnoid space)
Pia matter ‘faithful matter’ (ADHERENT TO BRAIN)

228
Q

What CN is the sensory supply to the dura?

A

CNV

229
Q

Which layer of the meninges encloses the dural venous sinuses? What are the main three types?

A

Dura matter

DIaphragm sellae, tentorium cerebelli, falx cerebri

230
Q

What is the diaphragm sellae? What does it sit upon?

A

Tough sheet of dura matter forming a roof over pituitary fossa (on sella turcica)

231
Q

What is the tentorium cerebelli?

A

Tough sheet of dura matter tenting over cerebellum, which attaches to ridges of petrous temporal bone

232
Q

What is the falx cerebri? What are the attachments to the deep aspect of skull?

A

Midline structure of dura matter that seperates the cerebral hemispheres
Crista galli of ethmoid bone, internal sagittal suture, internal occipital protuberance

233
Q

Where do the cerebral veins drain into?

A

Dural venous sinuses

234
Q

List the main dural venous sinuses that drain blood from the brain

A

Sigmoid sinus ‘S shape’
Superior sagittal sinus
Inferior sagittal sinus

235
Q

Where does the sigmoid sinus drain and to what foramen?

A

IJV at jugular foramen

236
Q

Where is the confluence of sinuses?

A

In midline at internal occipital protuberance

237
Q

What is the danger triangle of the face?

A

Venous spread of infection from superficial to deep - ophthalmic vein has no valves and can leak backwards = CAVERNOUS SINUS THROMBOSIS

238
Q

Outline the arterial supply to the brain

A
  1. ICA (branch of CCA)
  2. ECA (branch of CCA)
  3. VA (branch of SCA)
239
Q

What route does the vertebral artery take to reach the cranial cavity?

A

Through transverse foraminae in cervical vertebrae

Through foramen magnum

240
Q

Outline the branches of the Circle of Willis from bottom to top

A

Vertebral arteries (connected by anterior spinal)
Basilar artery (anastomosis of two VAs)
(Pontine arteries)
Posterior cerebral arteries (division of basillar artery)

ICAs (connected to PCAs by posterior communicating arteries)
1. Ophthalmic arteries
2. Branch of ICAs = Anterior cerebral arteries (connected by anterior communicating artery)
MCAs (continuation of ICAs)

241
Q

Which arteries supply the medial, lateral and posterior aspects of the cerebral hemispheres respectively?

A

ACAs
MCAs
PCAs

242
Q

Where can the Circle of Willis be found?

A

Inferior to midbrain, close to the pituitary stalk and optic chiasm in subarachnoid space

243
Q

What circulates within the subarachnoid space?

A

CSF

244
Q

Where does the subarachnoid space terminate?

A

S2 part of the sacrum

245
Q

Outline the route taken by CSF from production to reabsorption

A
  1. Secreted by choroid plexus
  2. From right and left lateral ventricles
    (via Foraminae of Munro - ONE FOR EACH)
  3. Into midline 3rd ventricle
    (Cerebral aqueduct)
  4. Into 4th ventricle
  5. Into subarachnoid space of brain and cord (and some into central canal)
  6. Reabsorbed into dural venous sinuses
246
Q

Where are the lateral ventricles, 3rd ventricle and 4th ventricle located, respectivelly?

A

Cerebral hemispheres
Diencephalon
Between cerebellum and pons

247
Q

What reabsorbs CSF back into the dural venous sinuses?

A

Arachnoid granulations

248
Q

What is hydrocephalus? How is it managed?

A

Excess production, obstruction to flow or inadequate reabsorption leading to increased CSF volume
Ventricular peritoneal shunt (connects ventricles to peritoneal cavity)

249
Q

List the types of bleeding that can occur within the cranial cavity and what causes each of them

A

EXTRADURAL HAEMORRHAGE (between bone and dura) due to ruptured middle meningeal artery (damage to pterior)

SUBDURAL HAEMORRHAGE (seperates dura from arachnoid) due to torn cerebral veins

SUBARACHNOID HAEMORRHAGE (into CSF of subarachnoid space) due to ruptured CIrcle of WIllis ‘Berry aneurysm’

250
Q

What can happen if you sustain damage to the extradural venous plexuses?

A

Epidural haematoma compressing spinal cord or cauda equina

251
Q

Where is the needle inserted in epidural anaesthesia? Why?

A

Subarachnoid space where it surrounds cauda equina (spinal nerves not as easily damaged as conus medullaris and vertebrae not fused)
Typically L3/4

252
Q

What are the four common types of supratentorial herniation?

A

Cingulate (under falx cerebri)
Central (through tentorium cerebelli)
Uncal (uncus = medial temporal lobe, inferior to tentorium cerebelli)
Transcalvarial (fracture of cranial cavity)

253
Q

What nerve can be compressed in uncal supratentorial herniation? What is the effect?

A

Oculomotor nerve

Fixed dilated pupil (ipsilateral)

254
Q

What are the two common types of infratentorial herniation?

A

Upward (over tentorium cerebelli)

Downward/ tonsillar herniation (of cerebral tonsils into foramen magnum)

255
Q

Where is the cerebral aqueduct located anatomically?

A

In the midbrain

256
Q

Which cranial nerve is located in the anterior midline of the midbrain?

A

Oculomotor nerve

257
Q

Which CN is the only nerve to exit the brainstem posteriorly?

A

Trochlear nerve - EXIT POSTERIOR MIDBRAIN AT JUNCTION WITH PONS

258
Q

What is different about cervical spinal nerves compared to other spinal nerves?

A

Cervical spinal nerves exit above the vertebrae but all others exit below

259
Q

If a patient has reduced sensation unilaterally on the face, including the forehead and lip, what does this suggest?

A

More likely involves peripheral facial nerve (Bell’s palsy) than a centrallesion (forehead sparing)

260
Q

How do you clinically test the L2 motor axons, supplying a myotome? What muscle are you testing?

A

Hip FLEX

Iliopsoas

261
Q

What pathology is often associated with Horner’s syndrome, due to the sympathetic nervous system travelling close to the site of damage?

A

Internal carotid dissection