Lab 9 Extremity Muscles: Attachments and Actions

What is the origin of the trapezius muscle?

Occipital bone

Where does the trapezius muscle insert?

Clavicle and scapula

What actions does the trapezius muscle perform?

Elevation and depression of the scapula; movement of cervical and thoracic vertebrae

What is the origin of the latissimus dorsi muscle?

Thoracic and lumbar vertebrae

Where does the latissimus dorsi muscle insert?

Humerus (near the greater tubercle)

What are the actions of the latissimus dorsi muscle?

Powerful extensor of the shoulder; adducts and rotates the humerus

What is the origin of the deltoid muscle?

Acromion of the scapula

Where does the deltoid muscle insert?

Deltoid tuberosity of the humerus

What actions does the deltoid muscle perform?

Abducts the arm; flexes and extends the arm at the shoulder joint

What is the origin of the pectoralis major muscle?

Clavicle, sternum, and true ribs

Where does the pectoralis major muscle insert?

Greater tubercle of the humerus

What are the actions of the pectoralis major muscle?

Flexes, adducts, and rotates the humerus

What is the origin of the supraspinatus muscle?

Supraspinous fossa of the scapula

Where does the supraspinatus muscle insert?

Greater tubercle of the humerus

What action does the supraspinatus muscle perform?

Abducts the arm at the shoulder joint

What is the origin of the infraspinatus muscle?

Infraspinous fossa of the scapula

Where does the infraspinatus muscle insert?

Greater tubercle of the humerus

What action does the infraspinatus muscle perform?

Rotates the shoulder joint

What is the origin of the teres minor muscle?

Greater tubercle of the humerus

Where does the teres minor muscle insert?

Greater tubercle of the humerus

What action does the teres minor muscle perform?

Adducts and rotates the arm at the shoulder joint

What is the origin of the biceps brachii muscle?

Coracoid process of the scapula

Where does the biceps brachii muscle insert?

Radial tuberosity of the radius bone

What action does the biceps brachii muscle perform?

Flexes the arm at the elbow joint; supinates the forearm

What is the origin of the triceps brachii muscle?

Posterior aspect of the humerus

Where does the triceps brachii muscle insert?

Olecranon of the ulna

What action does the triceps brachii muscle perform?

Extends the arm at the elbow joint

What is the origin of the sartorius muscle?

Anterior superior iliac spine

Where does the sartorius muscle insert?

Medial aspect of upper tibia

What actions does the sartorius muscle perform?

Flexes leg at the hip and knee joints; laterally rotates hip

What is the origin of the iliopsoas muscle?

Abdominopelvic cavity

Where does the iliopsoas muscle insert?

Lesser trochanter of the femur

What action does the iliopsoas muscle perform?

Major flexor of the hip