In this pdf-note, we’ll start with the borders of the upper limb:

• The anterior border is the deltopectoral groove

• The posterior border is the posterior deltoid groove

  

  

  Within the upper limb, there is a large number of regions:

• Deltoid region (regio deltoidea)

• Axillary region (regio axillaris)

• Anterior region of the arm (regio brachialis anterior)

• Posterior region of the arm (regio brachialis posterior)

• Anterior region of the elbow (regio cubitalis anterior)

• Posterior region of the elbow (regio cubitalis posterior)

• Anterior region of the forearm (regio antero brachialis anterior)

• Posterior region of the forearm (regio anterobrachialis posterior)

• Anterior region of the wrist (regio carpalis anterior)

• Posterior region of the wrist (regio carpalis posterior)

• Palmar region of the hand (regio palmaris manus)

• Dorsal region of the hand (regio dorsalis manus)

  

  

  Within these areas, the muscles of the upper limb are located.

  These include:

• Pectoral girdle muscles

• Muscles of the free part of the upper limb

  The muscles of the free part of the upper limb are divided into:

• Arm muscles

• Forearm muscles

• Hand muscles

  There are two groups of forearm muscles: anterior and posterior.

  The posterior group consists of the hand and finger extensor muscles. They are arranged in two layers.

  Superficial layer:

• Extensor carpi radialis longus muscle (m. extensor carpi radialis longus)

  

  

  

  Extensor carpi radialis longus muscle
  (m. extensor carpi radialis longus)

  Origin: lateral epicondyle of the humerus, lateral intermuscular septum of the arm

  Insertion: dorsal surface of the base of the 2nd metacarpal

  Function: flexes and abducts the hand

  Innervation: radial nerve (C5-C8)

  Blood supply: radial artery, radial collateral artery, radial recurrent artery

• Extensor carpi radialis brevis muscle (m. extensor carpi radialis brevis)

  

  

  

  Extensor carpi radialis brevis muscle
  (m. extensor carpi radialis brevis)

  Origin: lateral epicondyle of the humerus, radial collateral ligament

  Insertion: dorsal surface of the base of the 3rd metacarpal

  Function: flexes and abducts the hand

  Innervation: radial nerve (C5-C8)

  Blood supply: radial collateral artery, radial recurrent artery

• Extensor digitorum muscle (m. extensor digitorum)

  

  

  

  

  Extensor digitorum muscle
  (m. extensor digitorum)

  Origin: lateral epicondyle of the humerus

  Insertion: divides into 4 tendons, which insert into the dorsal surface of the fingers 2-5, forming the check ligaments. The middle bundles of this check ligament insert into the base of the middle phalanx, and the lateral bundles insert into the distal phalanx

  Function: extends the fingers 2-5 and the hand

  Innervation: radial nerve (C5-C8)

  Blood supply: posterior interosseous artery

• Extensor digiti minimi muscle (m. extensor digiti minimi)

  

  

  Extensor digiti minimi muscle
  (m. extensor digiti minimi)

  Origin: lateral epicondyle of the humerus

  Insertion: dorsal surfaces of the bases of the middle and distal phalanges of the 5th finger

  Function: extends the little finger

  Innervation: radial nerve (C5-C8)

  Blood supply: posterior interosseous artery

• Extensor carpi ulnaris muscle (m. extensor carpi ulnaris)

  

  

  Extensor carpi ulnaris muscle
  (m. extensor carpi ulnaris)

  Origin:

  Humeral head (caput humerale) arises from the lateral epicondyle of the humerus

  Ulnar head (caput ulnare) arises from the olecranon of the ulna

  Insertion: posterior surface of the base of the 5th metacarpal

  Function: flexes and abducts the hand

  Innervation: radial nerve (C6-C8)

  Blood supply: posterior interosseous artery

  Deep layer:

• Supinator muscle (m. supinator)

  

  

  Supinator muscle
  (m. supinator)

  Origin: lateral epicondyle of the humerus, radial collateral ligament, anular ligament of the radius, supinator crest of the ulna

  Insertion: superior third of the radius

  Function: supinates the radius relative to the ulna (supinates the hand)

  Innervation: radial nerve (C6-C8)

  Blood supply: radial artery, recurrent radial artery, interosseous artery

• Abductor pollicis longus muscle (m. abductor pollicis longus)

  

  

  

  Abductor pollicis longus muscle
  (m. abductor pollicis longus)

  Origin: posterior surface of the ulna and radius, interosseous membrane of the forearm

  Insertion: dorsal surface of the base of the 1st metacarpal

  Function: abducts the thumb

  Innervation: radial nerve (C5-C8)

  Blood supply: radial artery, posterior interosseous artery

• Extensor pollicis brevis muscle (m. extensor pollicis brevis)

  

  

  

  Extensor pollicis brevis muscle
  (m. extensor pollicis brevis)

  Origin: posterior surface of the radius, interosseous membrane of the forearm

  Insertion: base of the proximal phalanx of the thumb

  Function: extends the proximal phalanx of the thumb, abducts the thumb

  Innervation: radial nerve (C5-C8)

  Blood supply: radial artery, posterior interosseous artery

• Extensor pollicis longus muscle (m. extensor pollicis longus)

  

  

  Extensor pollicis longus muscle
  (m. extensor pollicis longus)

  Origin: posterior surface of the ulna, interosseous membrane of the forearm

  Insertion: base of the distal phalanx of the thumb

  Function: extends the thumb and the hand

  Innervation: radial nerve (C5-C8)

  Blood supply: radial artery, posterior interosseous artery

• Extensor indicis muscle (m. extensor indicis)

Dictionary

Forearm muscles

Deltoid region

regio deltoidea

Axillary region

regio axillaris

Anterior region of the arm

regio brachialis anterior

Posterior region of the arm

regio brachialis posterior

Anterior region of the elbow

regio cubitalis anterior

Posterior region of the elbow

regio cubitalis posterior

Anterior region of the forearm

regio anterobrachialis anterior

Posterior region of the forearm

regio anterobrachialis posterior

Anterior region of the wrist

regio carpalis anterior

Posterior region of the wrist

regio carpalis posterior

Palmar region of the hand

regio palmaris manus

Dorsal region of the hand

regio dorsalis manus

Extensor carpi radialis longus muscle

m. extensor carpi radialis longus

Extensor carpi radialis brevis muscle

m. extensor carpi radialis brevis

Extensor digitorum musle

m. extensor digitorum

Extensor digiti minimi muscle

m. extensor digiti minimi

Extensor carpi ulnaris muscle

m. extensor carpi ulnaris

Supinator muscle

m. supinator

Abductor pollicis longus muscle

m. abductor pollicis longus

Extensor pollicis brevis muscle

m. extensor pollicis brevis

Extensor pollicis longus muscle

m. extensor pollicis longus

Extensor indicis muscle

m. extensor indicis