MUSCLES OF UPPER LIMB

I.   MUSCLES THAT MOVE THE SCAPULA
A.  Trapezius: elevates and retracts scapula

B.  Rhomboids (major, minor): elevate and retract scapula

C.  Levator Scapulae: elevates scapula

D.  Pectoralis Minor:  protracts and depresses scapula

E.  Serratus Anterior: same as pectoralis minor

II.  MUSCLES THAT MOVE THE GLENOHUMERAL JOINT/ARM
–  Rule:  if a muscle crosses over/spans a joint, it must MOVE that joint!

A.  Muscles originating on Axial Skeleton

1.  Pectoralis Major:  flexes and adducts arm/humerus

2.  Latissimus Dorsi: extends and adducts arm/humerus

B.  Muscles originating on Scapula

1.  Deltoid: abducts, flexes, extends arm

What do you think?  How can the deltoid muscle both extend and flex the arm?

2.  Coracobrachialis: flexes, adducts arm

3.  Teres Major: extends, adducts arm

(note:  moving the glenohumeral joint is the same thing as moving the arm)

C.  “Rotator Cuff” Muscles

1.  Subscapularis: medially rotates arm

2.  Supraspinatus: abducts arm

3.  Infraspinatus: laterally rotates arm
4.  Teres Minor: laterally rotates arm

III. ARM MUSCLES THAT MOVE THE ELBOW JOINT/FOREARM

A.  Anterior arm muscles are Flexors of forearm/elbow joint:

1.  Biceps brachii
2.  Brachialis
3.  Brachioradialis

B.  Posterior arm muscles are Extensors of the forearm/elbow joint:

1.  Triceps brachii
2.  Anconeus

 

IV.  FOREARM MUSCLES
A.  Anterior Forearm contains pronator and flexor muscles

1.  Pronators of the forearm

a.  Pronator Teres
b.  Pronator Quadratus

 

2.  Flexors
-- flexor retinaculum         

 

 

Superficial Group

a.  Flexor Carpi Radialis: flexes wrist and abducts hand

b.  Palmaris Longus: flexes wrist

c.  Flexor Carpi Ulnaris: flexes wrist and adducts hand

Intermediate Group

d.  Flexor Digitorum Superficialis: flexes wrist and flexes digits 2 through 5 at the MP and PIP joints

 

MP=metacarpal-phalangeal
PIP=proximal interphalangeal

 

Deep Group

e.  Flexor Digitorum Profundus: flexes wrist and digits 2-5 at the MP, PIP and DIP joints

 

DIP=distal interphalangeal

f.  Flexor Pollicis Longus: flexes wrist, MP, IP joint of thumb

B.  Posterior Forearm contains supinator and extensor muscles

1.  Supinators of the forearm

a.  Supinator

 

2.  Extensors
-- extensor retinaculum

 

 

Superficial Group

a. Extensor Carpi Radialis Longus: extends wrist and abducts hand

b.  Extensor Carpi Radialis Brevis: extends wrist and abducts hand

c.  Extensor Digitorum: extends wrist and extends digits 2-5 at MP, PIP, and DIP joints

d.  Extensor Carpi Ulnaris: extends wrist and adducts hand

Deep Group

e.  Extensor Pollicis Longus: extends thumb

f.  Extensor Pollicis Brevis: extends thumb

g.  Abductor Pollicis Longus: abducts thumb

 

V.   HAND MUSCLES
A.  Thenar muscles: move the thumb
B.  Hypothenar muscles:move little finger

C.  Midpalmar muscles - move fingers 2-5
–  all of these muscles flex the MP joints and extend the PIP/DIP joints

1.  Lumbricals: (4)
2.  Palmar Interossei: (3) also adduct fingers
3.  Dorsal Interossei: (4) also abduct fingers

 

                  PAD – DAB

This muscle works with the brachialis to flex the elbow joint.

a. triceps brachii

b. anconeus

c. pectoralis major

d. brachioradialis

e. infraspinatus

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