Muscles of the Arm and Elbow
Actions of the Arm at the Elbow
• Flexion: bending at the elbow
• Extension: straightening at the elbow
• Pronation: moving the arm in a palms
down position
• Supination: moving the arm in a palms up
position
Muscles that act to Flex at the
elbow
• Most of these muscles are located on the
anterior side of the upper arm.
• Biceps brachii (prime mover)
• Brachialis
• Brachioradialis
Biceps Brachii
• Origin:
– Long head: supraglenoid
tubercle of scapula
– Short head: coracoid
process of the scapula
• Insertion:
– Radial tuberosity (radius)
• Actions:
– Flexion at the elbow
– Supination at the elbow
– Assists in flexion at the
shoulder
Brachialis
• Origin:
– Humerus
• Insertion:
– Coronoid process of the
ulna
• Action:
– Flexion at the elbow
Brachioradialis
• Origin:
– Humerus
• Insertion:
– Styloid process of the
radius
• Actions:
– Flexion at the elbow,
some pronation and
supination at the elbow
Muscles that act to Extend at the
elbow
• These muscles are located on the posterior
side of the upper arm
• Triceps brachii (prime mover)
• Anconeus:
– Major function is to stabilize elbow joint and
allow for maximal ROM during extension.
Triceps Brachii
• Origin:
– Long head: infraglenoid
tubercle of the scapula
– Medial head: humerus
– Lateral head: humerus
• Insertion:
– Olecranon process of the
ulna
• Actions:
– Extension at the elbow
– Long head: extension and
adduction of the shoulder
Anconeus
• Origin:
– Lateral condyle of the
humerus
• Insertion:
– Olecranon process of the
ulna
• Action:
– Extension of the elbow
Muscles that act to Pronate the
arm
• Pronator teres
• Pronator quadratus
• Brachioradialis
Pronator Teres
• Origin:
– Medial supracondylar
ridge of humerus, ulna
• Insertion:
– Radius
• Actions:
– Pronation, assists with
flexion at the elbow
Pronator Quadratus
• Origin:
– Ulna
• Insertion:
– Radius
• Action:
– Pronation at the wrist
Muscles that act to supinate at the
elbow
• Supinator
• Biceps brachii
• Brachioradialis
Supinator
• Origin:
– Lateral epicondyle
of the humerus,
ulna
• Insertion:
– Radius
• Action:
– Supination