5.3 UL Mucles & movements

Question 1

Muscles of the Shoulder / Scapula

4

Answer 1

Pectoralis Major
Pectoralis Minor
Deltoid
serratus anterior: attaching to ribs then attaching to underside of scapula
role: keep scapula gliding on thoracic wall, flat on rib cage

Question 2

5. 1 Deep intrinsic muscles of the back
   muscles all attach to and act on the back

Compare Erector spinae & Transversospinalis

Answer 2

E: long & strong, primer mover T:short, stabiliser

E: works concentrically from flex position to erect position
works eccentrically control flexion
T: prevent excess movement, atrophy rapidly after injury

Question 3

Intrinsic muscles of the hand

Answer 3

Thenar muscles (x4) base thumb
Hypothenar muscles (x3) base pinkie
Lumbricals (x4)
Interossei (x7)

Question 4

Medial epicondyle of humerus

Answer 4

Common flexor origin

Question 5

Muscles of the arm
Anterior compartment muscles
elbow flexors
Anterior-flexors
3

Answer 5

Biceps brachii-radius
Coracobrachialis-evoluntary structure
Brachialis-ulna

Question 6

Muscles of the arm
Posterior compartment muscles
elbow extensors
Posterior-extensors

Answer 6

Triceps brachii

3 distinct heads, 1 common tendon

Question 7

Muscles of the forearm
Anterior (flexor) compartment

Deep layer
3

Answer 7

flexor pollicis=thumb longus=long FPL: flexion of the thumb
flexor digitorum

profundus=profound=deep FDP: flexion of the digits

pronator quadratus PQ: pronation

arise from radius, ulna and interosseous membrane

Question 8

Muscles of the forearm
Anterior (flexor) compartment

Intermediate layer

Answer 8

flexor digitorum superficialis
FDS : flexion of digits & wrist flexion
FDS goes to the 4 digits, not to thumb
thumb unique digit

arise from CFO, radius & ulna
very powerful muscle
unique ‘splitting’ of tendons in digits

Question 9

Muscles of the forearm
Anterior-flexor compartment

Superficial layer
4 muscles

Answer 9

flexor carpi radialis FCR: lateral flexion of carpal bones- wrist
Flexor carpi ulnaris FCU: medial

Palmairs Longus PL: small muscle pulls skin down-reveal claws no major function, not present in some people, not present-more highly evolved

Pronator teres PT: pronation

Question 10

Muscles of the forearm
- Posterior (extensor) compartment
Deep layer

4
snuffbox

Answer 10

• supinator
• abductor pollicis longus (APL)*
• extensor pollicis brevis (EPB)*
• extensor pollicis longus (EPL)*
• extensor indicis (EI)

*snuffbox tendons

Question 11

Muscles of the forearm
- Posterior (extensor) compartment
Superficial layer

5

Answer 11

Brachioradialis
does not cross wrist
main action at elbow

• 3 muscles extend wrist:
  extensor carpi radialis longus (ECRL): long
  extensor carpi radialis brevis (ECRB): short
  extensor carpi ulnaris (ECU):
• 2 muscles extend digits:
  extensor digitorum communis (EDC): common
  extensor digiti minimi (EDM): little pinkie

Question 12

Superficial (extrinsic) muscles of the back

5

Answer 12

not 'true' back muscles - all attach to and act on the upper limb: 
• trapezius 
• levator scapulae 
• Rhomoboid minor 
• Rhomboid major
• Latissimus Dorsi

Question 13

Lateral epicondyle

Answer 13

common extensor origin