Lower arm and wrist muscles

Brachialis 

O: Distal half of the anterior surface of humerus

I: Tuberosity and coronoid process of ulna

Extensor Carpi Radialis Longus

O: Distal ⅓ of the lateral supracondylar ridge of humerus 

I: Base of the 2nd metacarpal

Extensor Pollicis Brevis

O: Posterior surface of radius and interosseous membrane

I: Base of proximal phalanx of thumb 

Extensor Carpi Radialis Brevis

O: Common extensor tendon from the lateral epicondyle of humerus

I: Base of 3rd metacarpal 

Extensor Pollicis Longus

O: Posterior surface of ulna and interosseous membrane

I: Base of distal phalanx of thumb

Abductor Pollicis Longus

O: posterior surface of radius, ulna, and interosseous membrane

I: base of 1st metacarpal 

Extensor Digitorum: 

O: Common extensor tendon from the lateral epicondyle of humerus 

I: Base of the middle and distal phalanges of 2nd-5th fingers

Extensor Carpi Ulnaris

O: common extensor tendon from the lateral epicondyle of humerus 

I: Base of the 5th metacarpal

Brachioradialis: 

O: Proximal ⅔ of lateral supracondylar ridge of humerus

I: Styloid process of radius 

Flexor Carpi Radialis: 

O: Common flexor tendon from medial epicondyle of humerus

I: Bases of 2nd-3rd metacarpals

Flexor digitorum profundus

O: anterior and medial surfaces of proximal ¾ of ulna

I: Bases of distal phalanges, palmar surface of 2nd-5th fingers

Palmaris Longus

O: common flexor tendon from medial epicondyle of humerus

I: Flexor retinaculum and palmar aponeurosis 

Flexor Carpi ulnaris 

O: Humeral head- Common flexor tendon from medial epicondyle of humerus

     Ulnar head- Posterior surface of proximal ⅔ of ulna

I: pisiform, hook and hamate, base of 5th metacarpal

Flexor Digitorum Superficialis

O: Common flexor tendon from medial epicondyle of humerus ulnar collateral ligament, coronoid process of ulna, interosseous membrane.

I: Base of middle phalanges of 2nd-5th fingers