May24 M3-Arm, elbow and cubital fossa Flashcards

1
Q

movements the forearm can do

A
  • flexion and extension

- pronation and supination (supination = anat position)

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

what nerve innervates the anterior compartment of muscles in the arm and what n. for posterior + function of each compartment + one exception

A
  • anterior = musculocutaneous n. = flexion of arm
  • posterior = radial n. = extension of arm
  • brachioradialis = posterior compt of arm to anterior of forearm = radial n. = flexion*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

compartment definition

A

muscle grouping sharing a closed fascia (CT)

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

number of muscles in ant and post forearm

A

ant = 3 muscles
post = 1 muscle
+ brachioradialis post arm to anterior forearm

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

compartment syndrome definition + what’s the problem

A

hematoma or trauma results in muscle swelling and this compresses the vessels going to muscles. get muscle dying. inflammation and pain

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

3 muscles in ant compt of arm

A
  • biceps brachii m.
  • coracobrachialis m.
  • brachialis m.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

biceps brachii how many heads and where tendons go on top (origin)

A

2 heads (biceps)

  • tendon of the long head (LATERAL) crosses the glenohumeral joint and goes to SCAPULA
  • tendon of short head (MEDIAL) attaches to coracoid process of the SCAPULA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

biceps brachii insertion

A
  • one tendon on radius (lateral bone forearm)

- an aponeurosis inserts on the ulna (medial bone forearm)

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

names of the aponeurosis of biceps brachii inserting on the ulna

A
  • bicipital aponeurosis

- flat tendon of the biceps brachii m.

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

biceps brachii functions (2) + inn.

A
  • flexion of arm and forearm (crosses glenohumeral joint and elbow joint)
  • supination of forearm
  • inn = musculocutaneous n.*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

brachialis m. origin, insertion, function and inn.

A
  • humerus to ulna
  • flexion of forearm
  • musculocutaneous n.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

coracobrachialis m. origin, insertion, function and inn.

A
  • scapula to humerus
  • flexion of ARM and ADDuction of the arm
  • musculocutaneous n.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

other name for arm

A

brachium

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

supination and pronation is what movement

A
pronation = radius crossing over the ulna on top of it
supination = radius back on side (lat) of ulna
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

full training of biceps brachii = what mvmts

A
  • supination of forearm
  • flexion of forearm
  • arm flexion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

only muscle in posterior compt of arm + how many heads and tendons

A

triceps brachii. 3 heads and 3 tendons on top (origin)

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

3 heads (on top) of the triceps brachii m. and where they originate from + location

A
  • long head (medial): from scapula (allows ADDuction)
  • lateral head (lateral): from humerus
  • medial head (deep between long and lateral heads: from humerus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

where triceps brachii m. inserts (the 3 heads insert where)

A

ulna

note: origin was scapula + humerus

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

function and innervation of triceps brachii m.

A
  • extension of the arm (bc of long head) and forearm
  • ADDuction of the arm
  • radial n.*
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what brachial artery becomes

A
  • same name all along the humerus
  • crosses elbow joint
  • after crosses elbow joint, splits in radial a. (lat) and ulnar a. (medial)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what cephalic and basilic v become

A
  • cephalic stays lat. and continues in forearm
  • basilic stays medial and continues in forearm
  • both connect at cubital fossa to form the median cubital vein
22
Q

cubital fossa is what

A

anterior interior fold of the elbow

23
Q

mechanism to prevent backflow of blood in veins of arm and forearm

A

valves

competent valve = functioning well

24
Q

how to check if a valve is functional

A
  • ID vein
  • put finger on vein and move distally until see a portion of the vein that is white (no blood there proximally valve blocking = one you’re checking and distally your finger is blocking)
25
Q

arteriovenous fistula links what vessels

A

radial artery and cephalic vein laterally

26
Q

musculocutaneous n. comes from what cord + spinal levels + to what muscles

A
  • from lateral cord
  • C5,6,7
  • to ant compt of arm
27
Q

musculocutaneous n. travels how

A
  • pierces coracobrachialis to go anterior to it

- travels anterior to coracobrachialis, between coracobrachialis and biceps + brachialis m.

28
Q

where radial n is located (don’t have to locate in anat lab)

A
  • posterior compt. cut lateral head of triceps

* crosses the triangular interval

29
Q

important concepts in sensory info coming back from limbs

A
  • is cutaneous + non cutaneous (feedback on muscle contraction and length)
  • in general**, n. innervating a m. also inn. the skin over this m.
30
Q

3 components of the cutaneous innervation of the arm

A
  • axillary n.
  • radial n.
  • cutaneous branches of the brachial plexus or of the intercostal nerves (medial brachial and antebrachial cutaneous n.)
31
Q

sensory inn. of axillary n.

A

skin over deltoid m.

32
Q

sensory inn. of radial n.

A

skin over triceps brachii m.

33
Q

sensory inn. of musculocutaneous n.

A

skin over the lateral surface of the FOREARM (not skin over biceps)

34
Q

sensory inn. of cutaneous branches of brachial plexus or of intercostal n. (medial brachial cutaneous n. and antebrachial cutaneous n.)

A

skin over the biceps

35
Q

shape of the cubital fossa and borders

A

triangle pointing downwards

  • lat border = brachioradialis m.
  • medial border = pronator teres m.
  • superior border = imaginary line between epicondyles of the humerus
36
Q

most superficial structure in the cubital fossa

A

median cubital vein

37
Q

3 structures deep to median cubital vein in the cubital fossa

A

lateral to medial:

  • biceps tendon (lat)
  • brachial artery
  • median nerve (most medial)
38
Q

2 places to feel brachial pulse

A
  • medial surface of biceps (find the brachial a. under the biceps brachii m.)
  • in the cubital fossa (+ also where you hear if taking manual BP)
39
Q

body landmarks on the surface of the elbow

A
  • lateral and medial epicondyles of the humerus

- olecranon of the ulna

40
Q

what is the funny bone

A

medial epicondyle of the humerus

41
Q

ulna and radius relation to each other

A
  • parallel in supination
  • opposite shapes. as you go distally, radius becomes wider but ulna becomes narrower
  • interosseus membrane between the two bones
42
Q

what’s the interosseus membrane between the forearm bones

A

CT fibers oriented medially and in a proximal-distal direction

43
Q

how the arm absorbs a shock

A
  • hand receives force
  • force transmitted from hand to RADIUS (wide distally)
  • radius transfers force to ulna via interosseus membrane
  • ulna (wider proximally) transfers force to humerus
44
Q

name given to absorption of shock by the arm + most fragile point in the system

A
  • circumvoluted dissipation of force

- wrist to radius transmission is most fragile

45
Q

how humerus, radius and ulna articulate

A

humerus has 2 surfaces

  • capitulum (lat) for radius
  • trochlea for ulna (medial)
46
Q

type of joint the elbow joint is

A

synovial joint (fluid in it): for more movement and less friction

47
Q

structures supporting the elbow joint

A
  • capsule (around the joint)
  • radial collateral ligament (lat epicondyle of humerus to radius)
  • ulnar collateral ligament (medial epicondyle of humerus to ulna)
  • annulus ligament (circle around the 3 bones at their articulation + gives a hole for the radius to fit in)
48
Q

2 important structures (supporting structures) in pronation and supination

A
  • annular ligament allows radius ROTATION ON THE SURFACE OF THE HUMERUS (capitulum) in pronation-supination
  • interosseus membrane prevents radius dislocation during pronation-supination
49
Q

ulna movement in pronation-supination

A

doesn’t move at all. well articulated with humerus

50
Q

why the ulna doesn’t move in pronation-supination, is well articulated with the humerus and can only do flexion-extension

A

the ulna wraps around the humerus (and not the opposite).

  • interior part wrapping around = coronoid process of the ulna
  • exterior part wrapping around = olecranon of the ulna
51
Q

what’s a pulled elbow

A
  • a dislocation of the radius from the annular ligament
  • dislocation of arm downwards
  • can happen in children held in the air by their hands (more likely in children bc their annular ligament is loose)
52
Q

clinical case: 1. rupture of biceps tendon on right side (right upper extremity)

  1. no fractures or dislocation
  2. swelling and pain
  3. numbness on lateral surface of right forearm
  4. diminished radial pulse on the right upper extremity
  5. weakness on elbow flexion
    * *Q: how do you account for the symptoms**: compt syndrome affecting median or ulnar or radial or musculocutaneous n. ?
A

compartment syndrome affecting the musculocutaneous nerve