Anatomy Flashcards
What are the sections of the brachial plexus?
Roots, trunks, divisions, cords, branches
Mnemonic:Real Teenagers Drink Cold Beer
What are the rami of the brachial plexus?
C5-T1
Where are the roots of the brachial plexus located?
Located in the posterior triangle of neck
Where are the trunks of the brachial plexus located ?
- Located posterior to middle third of clavicle
- Upper and middle trunks related superiorly to the subclavian artery
- Lower trunk passes over 1st rib posterior to the subclavian artery
Where are the divisions of the brachial plexus located?
Apex of the axilla
Where are the cords of the brachial plexus located?
Axillary artery
What foramen does CN I pass through?
Cribriform plate
What foramen does CN II pass through?
Optic canal
What foramen does CN III pass through?
Superior orbital fissure
What foramen does CN IV pass through?
Superior orbital fissure
What foramen does CN V pass through?
V1: SOF
V2: Foramen rotundum
V3: Foramen ovale
What foramen does CN VI pass through?
SOF
What foramen does CN VII pass through?
Internal auditory meatus
What foramen does CN VIII pass through?
Internal auditory meatus
What foramen does CN IX pass through?
Jugular foramen
What foramen does CN X pass through?
Jugular foramen
What foramen does CN XI pass through ?
Jugular foramen
What foramen does CN XII pass through?
Hypoglossal canal
What is the function of CN III? What does a palsy look like?
Eye movement (MR, IO, SR, IR)
Pupil constriction
Accomodation
Eyelid opening
Palsy results in
- ptosis
- ‘down and out’ eye
- dilated, fixed pupil
What is the function of CN IV? What does a palsy look like?
Eye movement (SO)
Palsy results in defective downward gaze → vertical diplopia
What is the function of CN V? What does a palsy look like?
Facial sensation
Mastication
Lesions may cause:
trigeminal neuralgia
loss of corneal reflex (afferent)
loss of facial sensation
paralysis of mastication muscles
deviation of jaw to weak side
What is the function of CN VI? What does a palsy look like?
Eye movement of lateral rectus
Palsy results in defective abduction → horizontal diplopia
What is the function of CN VII? What does a palsy look like?
Facial movement
Taste (anterior 2/3rds of tongue)
Lacrimation
Salivation
Lesions may result in:
flaccid paralysis of upper + lower face
loss of corneal reflex (efferent)
loss of taste
hyperacusis
What is the function of CN VIII? What does a palsy look like?
Function: Hearing and balance
Palsy:
Hearing loss
Vertigo, nystagmus
Acoustic neuromas are Schwann cell tumours of the cochlear nerve
What is the function of CN IX? What does a palsy look like?
Taste (posterior 1/3rd of tongue)
Salivation
Swallowing
Mediates input from carotid body & sinus
Lesions may result in;
hypersensitive carotid sinus reflex
loss of gag reflex (afferent)
What is the function of CN IX? What does a palsy look like?
Taste (posterior 1/3rd of tongue)
Salivation
Swallowing
Mediates input from carotid body & sinus
Lesions may result in;
hypersensitive carotid sinus reflex
loss of gag reflex (afferent)
What is the function of CN X? What does a palsy look like?
Phonation
Swallowing
Innervates viscera
Lesions may result in;
uvula deviates away from site of lesion
loss of gag reflex (efferent)
What is the function of CN XI? What does a palsy look like?
Head and shoulder movement
Lesions may result in;
weakness turning head to contralateral side
What is the function of CN XII? What does a palsy look like?
Tongue deviates towards side of lesion
What cranial nerves are involved in the corneal reflex?
Afferent: Ophthalmic nerve (V1)
Efferent: Facial nerve (VII)
What cranial nerves are involved in the jaw jerk?
Afferent: Mandibular nerve (V3)
Efferent: Mandibular nerve (V3)
What cranial nerves are involved in the gag reflex?
Afferent: Glossopharyngeal nerve (IX)
Efferent: Vagal nerve (X)
What cranial nerves are involved in the carotid sinus?
Afferent: Glossopharyngeal nerve (IX)
Efferent: Vagal nerve (X)
What cranial nerves are involved in the pupillary light reflex?
Afferent: Optic nerve (II)
Efferent: Oculomotor nerve (III)
What cranial nerves are involved in lacrimation?
Afferent: Ophthalmic nerve (V1)
Efferent: Facial nerve (VII)
What does the C2 dermatome innervate?
Posterior half of the skull (cap)
What does the C3 dermatome innervate?
High turtleneck shirt
What does the C4 dermatome innervate?
Low-collar shirt
What does the C5 dermatome innervate?
Ventral axial line of upper limb
What does the C6 dermatome innervate?
Thumb + index finger
Make a 6 with your left hand by touching the tip of the thumb & index finger together - C6
What does the C7 dermatome innervate?
Middle finger + palm of hand
What does the C8 dermatome innervate?
Ring + little finger
What does the T4 dermatome innervate?
Nipples
What does the T5 dermatome innervate?
Inframammory fold
What does T10 dermatome innervate?
Belly button
What does L1 dermatome innervate?
L for ligament, 1 for 1nguinal
What does L4 dermatome innervate?
Down on aLL fours - L4
What does L5 dermatome innervate?
Big toe, dorsum of foot (except lateral aspect)
What does the S1 dermatome innervate?
Lateral foot, small toe
What is the motor and sensory function of the femoral nerve?
What is the sensory function?
Motor: Knee extension, thigh flexion
Sensory: Anterior and medial aspect of the thigh and lower leg
What is the motor function of the obturator nerve?
What is the sensory function?
Motor: Thigh adduction
Sensory: Medial thigh
WHat is the sensory function of the lateral cutaneous nerve of the thigh?
Lateral and posterior surfaces of the thigh
Motor and sensory function of the tibial nerve?
Foot plantarflexion and inversion
Sole of foot
Motor and sensory function of common pudendal nerve?
Motor: Foot dorsiflexion and eversion. Extensor hallucis longus
Sensory: Dorsum of the foot and the lower lateral part of the leg
Motor and sensory function of superior gluteal nerve ?
Sensory function?
Hip ABduction
Sensory function Nil
Motor and sensory function of inferior gluteal nerve ?
Sensory function?
Motor Hip extension and lateral rotation
Sensory function: Nil
What are the boundaries of the popliteal fossa?
Laterally Biceps femoris above, lateral head of gastrocnemius and plantaris below
Medially Semimembranosus and semitendinosus above, medial head of gastrocnemius below
Floor Popliteal surface of the femur, posterior ligament of knee joint and popliteus muscle
Roof Superficial and deep fascia
What are the contents of the popliteal fossa?
Popliteal artery and vein
Small saphenous vein
Common peroneal nerve
Tibial nerve
Posterior cutaneous nerve of the thigh
Genicular branch of the obturator nerve
Lymph nodes
What are the nerve roots of the radial nerve?
Continuation of posterior cord of the brachial plexus (root values C5 to T1)
What is the motor function of the radial nerve?
Main branch:
Triceps
Anconeus
Brachioradialis
Extensor carpi radialis
Posterior interosseus:
Supinator
Extensor carpi ulnaris
Extensor digitorum
Extensor indicis
Extensor digiti minimi
Extensor pollicis longus and brevis
Abductor pollicis longus
What is the sensory function of the radial nerve?
The area of skin supplying the proximal phalanges on the dorsal aspect of the hand is supplied by the radial nerve (this does not apply to the little finger and part of the ring finger)
What is the pattern of radial nerve damage?
wrist drop
sensory loss to small area between the dorsal aspect of the 1st and 2nd metacarpals
What nerve roots does the ulnar nerve arise from?
arises from medial cord of brachial plexus (C8, T1)
What does the ulnar nerve supply motor innervation to?
medial two lumbricals
aDductor pollicis
interossei
hypothenar muscles: abductor digiti minimi, flexor digiti minimi
flexor carpi ulnaris
What does the ulnar nerve supply sensory innervation to?
medial 1 1/2 fingers (palmar and dorsal aspects)
What is the pattern of damage to the ulnar nerve?
‘claw hand’ - hyperextension of the metacarpophalangeal joints and flexion at the distal and proximal interphalangeal joints of the 4th and 5th digits
wasting and paralysis of intrinsic hand muscles (except lateral two lumbricals)
wasting and paralysis of hypothenar muscles
sensory loss to the medial 1 1/2 fingers (palmar and dorsal aspects)
What is the ulnar paradox?
ulnar paradox - clawing is more severe in distal lesions
What is special about the C8 spinal nerve?
C8 nerve root exits the spine below the C7 vertebra, being the only cervical nerve root which exits below a vertebra. The rest of the cervical nerve roots derive their name from the vertebra below them. The most common acute pathology causing a radiculopathy is a disc herniation and therefore this is the correct answer.
