Major Muscles of the Human Body Flashcards
Neck
1. Sternocleidomastiod
Origin: sternum and clavicle
Insertion: mastoid process
Function: flexes the head from side to side and rotates the neck
Deep Vertebral Column
— Erector Spinae Group
1. Spinalis
(most medial)
Origin: cervical and thoracic vertebrae
Insertion: cervical and thoracic vertebrae
Function: extends and laterally flexes the spine
Deep Vertebral Column
- Erector Spinae Group
2. Longissimus
(more lateral than spinalis)
Origin: cervical, thoracic and lumbar vertebrae
Insertion: mastoid process, cervical and thoracic vertebrae
Function: extends and laterally flexes the spine and head
Deep Vertebral Column
- Erector Spinae Group
3. Iliocostalis
(most lateral)
Origin: sacrum, lumbar vertebrae and the ribs
Insertion: ribs and the cervical vertebrae
Function: extends and laterally flexes the spine
Thoracic Cage
1. Diaphragm
Origin: sternum, the ribs and the lumbar vertebrae
Insertion: central tendon
Function: increases volume of the ribs and decreases pressure in the thoracic cavity, thus drawing in air
Thoracic Cage
2. Internal Intercostals
Origin: inferior aspect of all ribs
Insertion: superior aspects of all the ribs
Function: elevation and depression of ribs
Abdomen
1. Rectus Abdominis
Origin: pubic crest
Insertion: xiphoid process and the inferior ribs
Function: flexes the trunk
Abdomen
2. External Obliques
Origin: lower 8 ribs
Insertion: iliac crest and pubis
Function: flexes and rotates vertebral column and compress abdomen
Upper Limbs
1. Pectoralis Major
Origin: clavicle, lower sternum and first to sixth ribs
Insertion: intertubercular groove
Function: internal rotation, adduction and flexion of the arm
Upper Limbs
2. Latissimus Dorsi
Origin: lumbar vertebrae, half of the thoracic vertebrae, iliac crest and sacrum
Insertion: intertubercular groove of the humerus
Function: adducts, extends and internally rotates
Rotator Cuff
1. Supraspinatus
Origin: supraspinous fossa of scapula
Insertion: greater tubercle of the humerus
Function: stabilizes the shoulder joint and abducts the shoulder
Rotator Cuff
2.Infraspinatus
Origin: infraspinous fossa
Insertion: greater tubercle of the humerus
Function: stabilizes the shoulder joint and laterally rotates the shoulder
Rotator Cuff
3. Teres Minor
Origin: lateral border of the scapula
Insertion: greater tubercle of the humerus
Function: stabilizes the shoulder joint and laterally rotates the shoulder
Rotator Cuff
4. Subscapularis
Origin: subscapular fossa of scapula
Insertion: lesser tubercle of the humerus
Function: rotates the humerus medially and stabilizes the shoulder
Scapula
1. Trapezius
Origin: base of the occipital bone, cervical and thoracic vertebrae
Insertion: spine of the scapula, the acromion process and the clavicle
Function: scapular elevation, adduction/retraction, upward rotation, depression and the extension of the neck
Scapula
2. Rhomboid Major and Minor
Origin: - major T2-T5 - minor C7-T1
Insertion: lower medial border of the scapula
Function: elevates scapula and rotates scapula downward
Scapula
3. Levator Scapulae
Origin: C1-C4
Insertion: medial border of scapula
Function: elevates the scapula and rotates the scapula downward
Scapula
4. Pectoralis Minor
Origin: third rib to fifth rib
Insertion: corocoid process of the scapula
Function: elevates the ribs, depresses and protracts the scapula
Scapula
5. Deltoid
Origin: the clavicle, acromion and the spine of the scapula
Insertion: deltoid tuberosity of the scapula
Function: - anterior medially rotates - lateral abducts the arm - posterior extends and laterally rotates the arm
- Teres Major
Origin: inferior lateral border of the scapula
Insertion: intertubercular groove of the humerus
Function: medially rotates, adducts and extends the humerus at the arm
Flexors and Extensors
1. Biceps Brachii
Origin: - short coracoid process - long supraglenoid tubercle
Insertion: radial tuberosity
Function: supinates forearm and flexes the elbow
Flexors and Extensors
2. Brachialis
Origin: lower anterior surface of the humerus
Insertion: coranoid process of ulna
Function: flexes the elbow
Flexors and Extensors
3. Triceps Brachii
Origin: - lateral, posterior aspect of humerus - long, infraglenoid tubercle of scapula - medial, posterior aspect of humerus
Insertion: olecranon process of ulna
Function: extensor of the arm
Flexors and Extensors
4. Brachioradialis
Origin: lateral epicondyle of humerus
Insertion: styloid process of the radius
Function: flexes the elbow and plays the biggest part when arm is pronated
- Pronator Teres
Origin: medial epicondyle of humerus and coronoid process of the ulna
Insertion: mid-lateral surface of radius
Function: Pronates arm and flexes elbow
- Supinator
Origin: lateral epicondyle of humerus
Insertion: anterior and lateral aspects of radious
Function: supinates the arm
