A and P lab 7 Muscles of extremities

Deltoid function

Abduction of Humerus

Deltoid origin

Acromion and spin of scapula

Deltoid insertion

Deltoid tuberosity of humerus

Rotator Cuff Muscles (SITS)

• Supraspinatus

• Infraspinatus

• Teres Minor

• Subscapularis

Rotator cuff muscle functions

Supraspinatus: abduction of humerus

Infraspinatus: external rotation of humerus

Teres Minor: external rotation and adduction of humerus

Subscapularis: Internal rotation and adduction of humerus

Rotator cuff muscle origins

Supraspinatus: Supraspinous fossa

Infraspinatus: Infraspinous fossa

Teres Minor: Lateral border

Subscapularis: Subscapular fossa

(All scapula)

Rotator cuff insertions

Supraspinatus: Greater tubercle

Infraspinatus: Greater tubercle

Teres Minor: Greater tubercle

Subscapularis: lesser tubercle

(All Humerus)

Biceps brachii function

Elbow flexion and forearm supination

Bicep Brachii origin

Long head: superior edge of glenoid cavity

Short head: coracoid process

Bicep Brachii insertion

Radial tuberosity

Brachioradialis function

Elbow flexion

Brachioradialis origin

lateral supracondylar ridge of humerus

Brachioradialis Insertion

radial styloid process

Triceps Brachii function

Extends humerus

Long head extends and adducts humerus

Triceps Brachii origin

Long head: inferior edge of glenoid cavity

Medial head: posterior humerus shaft

Lateral head: posterior humerus shaft

Triceps Brachii insertion

olecranon process

Pronator quadratus function

Pronates forearm

Pronator quadratus origin

Anterior surface of distal ulna

Pronator quadratus insertion

lateral surface of radius

Gluteal muscles

• Gluteal maximus

• Gluteal medius

• Gluteal minimus

Gluteal muscle functions

Gluteal maximus: extends thigh

Gluteal medius: abducts and medially rotates thigh

Gluteal minimus: abducts and medially rotates thigh

Gluteal muscle origins

Gluteal maximus: Dorsal ilium, sacrum, coccyx

Gluteal medius: Lateral surface of ilium

Gluteal minimus: External surface of ilium

(All pelvis)

Gluteal muscle insertions

Gluteal maximus: Gluteal tuberosity and iliotibial band

Gluteal medius: gluteal tuberosity

Gluteal minimus: greater trochanter

(All femur)

Iliopsoas muscles

• iliacus

• psoas major

Iliopsoas muscle functions

iliacus: flexes thigh toward trunk

psoas major: Flexes thigh toward trunk and flexes vertebral column laterally

Iliopsoas origins

iliacus: Crest and fossa of ileum, ala of sacrum

psoas major: bodies and intervertebral discs of T12-L5

Iliopsoas insertions

iliacus: lesser trochanter

psoas major: lesser trochanter