Muscle of the Arm and Forearm dorsal/posterior. 3 groups 1. Muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the.

The Muscular SystemMuscle of the Arm and Forearm dorsal/posterior

Muscles of the Upper Limb

3 groups

1. Muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the humerus

2. Muscles that cause movement at the elbow which insert on the forearm bones

3. Muscles of the forearm which insert on the hand bones

General Organization

Upper Limb Extensors on the posterior/dorsal

surface

Muscles that act on the wrist

Generally originate on the distal humerus Extensors on the lateral epicondyle

Insert on the carpals and metacarpals

Muscles that act on the fingers

Generally originate on the distal humerus Extensors on the lateral epicondyle

Insert on the phalanges

Clavobrachialis (Clavodeltoid):

Deltoid muscle in humansAction:

Abducts the shoulderOrigin:

Clavicle and scapula Insertion:

Deltoid tuberosity of humerus

Triceps brachii

Action: antagonist of biceps Extension (shoulder and elbow)

Origin: three heads Shoulder girdle and proximal humerus

Insertion: Olecranon process of ulna

Brachioradialis:

Action: Flexion at the elbow

Origin: lateral epicondyle of the humerus

Insertion: Styloid process of the radius

Extensor carpi radialis

Action: Extension/abduction

(wrist)Origin:

Lateral epicondyle Insertion:

Second and third metacarpals

Extensor digitorum

Action: Extension (fingers

and wrist)Origin:

Lateral epicondyle Insertion:

Posterior surfaces of phalanges

Extensor carpi ulnaris

Action: Extension/

adduction (wrist)Origin:

Lateral epicondyle Insertion:

Base of 5th metacarpal

Dorsal Surface

clavobrachialis

Triceps brachii

brachioradialis

Extensor carpi radialis

Extensor digitorum

Extensor carpi ulnaris

Posterior/dorsalTriceps brachii

brachioradialis

Posterior/dorsalTriceps brachii

brachioradialis

Flexor carpi

ulnaris

Extensor carpi radialis

Extensor carpi ulnaris

Posterior/dorsalTriceps brachii

brachioradialis

Flexor carpi

ulnaris

Extensor carpi radialis

Extensor carpi ulnaris

Extensor digitorum