Muscles of Upper Limb: Arm, Forearm, and Hand Flashcards
Anterior Compartment of Arm: 3 Muscles
biceps brachii, brachialis, coracobrachialis
all are flexors of either arm or forearm
Coracobrachialis
action: flexes and adducts arm
Origin: scapula
Insertion: humerus
Brachialis
action: flexes forearm
Origin: humerus
Insertion: ulna
Biceps Brachii
2 heads: short and long
Actions: flexes and supinates forearm
Origin: humerus
Insertion: radial tuberosity
What’s the only muscle in the posterior compartment of the arm?
Triceps brachii
Triceps Brachii
3 heads: long, medial, lateral
actions:
- -long head: extends forearm and arm
- -medial and lateral heads: extend forearm
Origin:
–long head: scapula
–medial and lateral heads: humerus
Insertion (all 3 heads): ulna - olecranon
Brachioradialis
primarily located in anterior compartment of forearm
action: flexes forearm
Origin: humerus
Insertion: radius
What are the 2 forearm muscles?
Flexor muscles
Extensor muscles
Flexor Muscles (anterior compartment)
forearm muscles
action: flex wrist and digits
Origin: humerus medial epicondyle and forearm
Insertion: wrist and digits
Extensor Muscles (posterior compartment)
forearm muscles
action: extend wrist and fingers
Origin: humerus lateral epicondyle and forearm
Insertion: wrist and digits
Tennis Elbow (Lateral Epicondylitis)
The extensor muscles of the forearm attach to lateral epicondyle of humerus.
Overuse or trauma
What are the 3 intrinsic muscles of the hand?
Thenar group
Hypothenar group
Interossei
Thenar Group
intrinsic muscles of the hand
action: move thumb, opposes to digits
Origin: wrist
Insertion: pollex
Hypothenar Group
intrinsic muscles of the hand
action: move digit 5, opposes to thumb
Origin: wrist
Insertion: 5th digit
Interossei
intrinsic muscles of the hand
action: abducts and adducts digits
Origin: metacarpals 2-5
Insertion: phalanges 2-5
