misc C+M Flashcards
A patient is concerned with their hearing and sometimes fails to recognise familiar tastes. He is also unstable when he gets out of bed. If cranial nerves are responsible for these symptoms, where is the most likely location?
Lateral pontomedullary junction
how would you describe flexion and extension of the shoulder
same direction as flexion and extension of the hip!
flexion = swinging arm forward (eg while walking)
extension = swinging arm back
latissimus dorsi muscle:
- origin
- insertion
- actions 3
- innervation
origin:
- broad: spinous processes of T6 to T12, illiac crest, thoracolumnar fascia + inferior 3 ribs
insertion:
- intertubercular sulcus of the humerus
actions:
- extends shoulder
- adducts shoulder
- medially rotates shoulder
innervation:
- thoracodorsal nerve
trapezius:
- origin?
- insertion?
- action of upper fibres? 2
- action of middle fibres? 1
- action of lower fibres? 1
- innervation?
origin:
- skull
- nuchal ligament
- spinous processes of C7 - T12
insertion:
- clavicle
- acromion
- spine of scapula
upper fibres:
- elevate scapula
- rotate scapula (during abduction of arm))
middle fibres:
- retract scapula
lower fibres:
- pull scapula inferiorly (depress)
what are the possible movements of the scapula?
- elevation
- depression
- protraction (hunch shoulders forward)
- retraction (pull shoulders back, shoulder blades closer together)
- upwards rotation (seen when arm is aBducted)
- downwards rotation (seen when arm is aDucted)
levator scapulae:
- origin?
- insertion?
- action?
- innervation?
origin:
- TRANSVERSE processes of the C1-C4 vertebrae
insertion:
- medial border of scapula
action:
- elevates scapula (clue’s in the name)
innervation:
- dorsal scapula nerve
rhomboid major + minor:
- origins?
- insertions?
- actions? 2
- innervation?
rhomboid major:
- origin = spinous processes of T2-T5
- insertion = medial border of scapula, between scapula spine + inferior angle
rhomboid minor:
- origin = spinous processes of C7-T1
- insertion = medial border of scapula, at level of scapula spine
nb rhomboid minor sits superior to rhomboid major
actions:
- retracts scapula
- rotates scapula
innervation:
- dorsal scapula nerve
what are the three groups of muscles of the back?
what could each be said to mainly control?
superficial
- associated with movements of the shoulder
intermediate
- associated with movements of thoracic cage
deep
- associated with movements of the vertebral column
list the superficial back muscles? 5
- trapezius
- levator scapulae
- rhomboid minor
- rhomboid major
- lat dorsi
nb all innervqated by dorsal scapula nerve (except trapezius is innervated by accessory nerve CN11)
what structure is cut through in a laryngotomy?
cricothyroid cartilage
what is the difference between ulnar claw and hand of benediction?
incl nerve damaged and muscles paralysed
lnar claw: paralysis of the medial 2 lumbricals means that, when your hand is RESTING, your pinky and ring finger are flexed at IP and extended at MCP
Hand of benediction: paralysis of all extrinsic flexors in forearm EXCEPT flexor carpi ulnaris and medial half of flexor digitorum profundus! Therefore, when the person tries to make a fist they can flex the MCP + IP joints of the pinky and ring but CANT flex the index and middle finger!
So basically you get the same ‘claw’ in both pathologies but you see it at rest in ulnar claw and when asked to make a fist in hand of benediction!
what movement is the scapula unable to perform if the long thoracic nerve is damaged?
what may cause this damage?
unable to PROtract the scapula
-> winging of the scapula
eg axillary lymph node clearance for breast carcinoma
what branch of the median nerve passes through the carpal tunnel + supplies the thenar eminence?
recurrent branch of the median nerve
what is the innervation of the lumbricals?
median 2 lumbricals = ulnar nerve
lateral 2 lumbricals
= median nerve
what is the arterial blood supply to the:
- internal capsule + basal ganglia?
- thalamus?
internal capsule + basal ganglia:
- striate arteries (branch off the medial cerebral artery)
thalamus:
- branches of the posterior cerebral artery
what two muscles are likely to be injured due to a laceration of the webspace between the 1st + 2nd digits?
- the first dorsal interosseous
- adductor pollicis
substantia gelatinosa:
- function?
- located in which rexed laminae of the spinal cord grey matter?
an area in the dorsal horn of the spinal cord where afferent pain fibres synapse
- it is important in the gate-control mechanism of pain sensation
rexed laminae number II
“the pain is not TWO bad”
on an ultrasound of the leg, do muscles appear lighter or darker when they are tensed?
darker (as get more dense!)
dense stuff appears darker on ultrasound (opposite to x-ray) as echowaves can’t pass through it
where do the lateral and medial circumflex arteries of the hip normally arise from?
the profunda femoris artery
only rarely from the femoral
which artery supplies an acetabular branch to the head of the femur?
obturator artery
what causes night blindness?
absense/loss of rod cells
can be congenital or acquired through infection etc
What are the boundaries of the deltopectoral (clavipectoral) triangle?
What structure lies in this triangle?
Mediosuperior = clavicle Superolateral = deltoid Inferomedial = pec major
Cephalic vein
What are the actions of pec major?
Together:
- adducts + medially rotates humerus
Just clavicular head:
- flexes humerus
Just sternocostal head: extends humerus
What is the action of pec minor?
Stabilises scapula by drawing anteroinferiorly against thoracic wall
What is the insertion of serratus anterior?
Costal (rib facing) surface of medial border of scapula
What form the borders of the axilla?
Anterior: pec major + minor
Posterior: scapularis, teres major, lat dorsi
Lateral: intertubercular sulcus of humerus
Medial: serratus anterior + thoracic wall
What are the 5 sections of the brachial plexus?
- roots
- trunks
- divisions
- cords
- terminal branches
Which cords of the brachial plexus contribute to the:
- musculocutaneous nerve?
- axillary nerve?
- radial nerve?
- median nerve?
- ulnar nerve?
Musculocutaneous:
- lateral cord
Axillary:
- posterior cord
Radial:
- posterior cord
Median:
- lateral AND medial cord
Ulnar: medial cord
Nb the cords are named for their position around the axillary artery
Biceps brachii:
- proximal attachments?
- insertion?
- actions? 3
Proximal attachments
- short head: coracoid process of scapula
- long lead: supraglenoid tubercle of scapula
Insertion
- radial tuberosity (on radius) + fascia of forearm
Actions - supination of forearm - flex arm at shoulder - flex arm at elbow Nb especially during supination
brachialis:
- origin?
- insertion?
- action?
origin:
- medial + lateral surfaces of humeral shaft
insertion:
- ulna tuberosity (on ulna)
action:
- flexion of elbow (esp during pronation)
nb biceps brachii flexes elbow during supination, brachialis during pronation
coracobrachialis:
- origin?
- insertion?
- action?
origin:
- coracoid process of the scapula
insertion:
- medial surface of humeral shaft (at level of deltoid tubercle)
action:
- flexion of arm at shoulder (+ weak adduction)
what is quadrilateral space syndrome?
compression of the axillary nerve in the quadrilateral space -> paralysis + atrophy of deltoid
what causes a ‘painful arc’?
sub acromial bursitis
basically the tendons compress the inflammed bursa
-> pain during this ‘arc’ between 60-120 deg rotation of shoulder
what is frozen shoulder?
aka?
adhesive capsulitis
pain + stiffness in shoulder due to swollen + thickened capsule
teres major:
- origin?
- insertion?
- actions? 2
- innervation?
origin:
- post surface of the inferior angle of the scapula
insertion:
- intertubercular groove of the humerus
actions:
- adducts shoulder
- medially rotates arm
innervation:
- lower subscapular nerve
what are the 4 rotator cuff muscles
- which nerve is each innervated by?
supraspinatus
- suprascapular nerve
infraspinatus
- suprascapular nerve
subscapularis
- upper + lower subscapular nerve
teres minor
- axillary nerve
nb sub scapularis is on costal (anteroinferior) side of scapula, the others are on the posterosuperior side
where do the rotator cuff muscle insert?
what is the action of each of them, individually?
supraspinatus, infraspinatus + teres minor all insert at GREATER tuberosity and are LATERAL rotators
subscapularis inserts aat LESSER tuberosity and is a MEDIAL rotator
supraspinatus ALSO initiates ABDUCTION of the arm and does first 0-15 degs (then deltoid takes over!)
what is the name of the canal in the wrist through which the ulnar nerve travels?
Guyon’s canal
which epicondyle is affected in:
- golfers elbow?
- tennis elbow?
golfers = medial
tennis = lateral
“in golf you hold club close to body whereas tennis racket is held away from your body”
