A&P 1 - Lab Manual Unit 3

Psoas Major

I: lesser trochanter of femur

A: flexes at hip

Iliacus

O: iliac fossa

A: flexion at hip

Piriformis (cant see on model)

O: anterolateral surface of sacrum

I: greater trochanter of femur

A: lateral rotation and abduction at hip

Gracilis

O: inferior ramus of pubis

I: medial surface of tibia

A:

• knee flexion

• adducts thigh

• medially rotates at hip

Adductor Magnus (cant see on model)

O: inferior ramus of pubis and ischial tuberosity

I: linea aspera of femur and adductor tubercle of femur

A: adduction at hip (part can do flexion and medial rotation at hip; inferior part can produce extension and lateral rotation at hip)

Adductor Longus

O: body of pubis

I: linea aspera of femur

A:

• adduction at hip

• can contribute to flexion and medial rotation of hip

Gluteus Maximus

I:

• (IT) tract

• gluteal tuberosity of femur

A:

• extension (moves leg backward)

• lateral rotation at hip (turns leg outward)

Gluteus Medius (can’t see on model)

O: anterior iliac crest of ilium

I: greater trochanter of femur

A: abduction and medial rotation of hip

Tensor Fasciae Latae

O: iliac crest and (ASIS)

I: (IT) tract

A:

• abduction (moves leg away from midline)

• medial rotation of hip

Sartorius

O: (ASIS)

I: medial surface of tibia

A:

• flexes knee

• flexion

• lateral rotation of hip

Rectus Femoris

O: (AIIS) and superior acetabular rim of ilium

I: tibial tuberosity via patellar ligament

A:

• extension at knee

• flexion at hip

Vastus Medialis

O: linea aspera of femur

I: tibial tuberosity via patellar ligament

A: extends knee

Vastus Intermedius (can’t see on model)

Origin, Insertion, Action: same as vastus medialis (linea aspera of femur; tibial tuberosity via patellar ligament; extends knee)

Vastus Lateralis

Origin, Insertion, Action: same as vastus medialis (linea aspera of femur; tibial tuberosity via patellar ligament; extends knee)

Biceps Femoris

O: ischial tuberosity and linea aspera of femur

I: head of fibula

A:

• flexion at knee (bends the leg)

• extension

• lateral rotation at hip

Semitendinosus

O: ischial tuberosity

I: proximal and medial end of tibia

A:

• flexion at knee

• extension

• medial rotation at hip

Semimembranosus

O: ischial tuberosity

I: medial condyle of tibia

A:

• flexion at knee

• extension

• medial rotation at hip

Gastrocnemius

O: femoral condyles

I: calcaneus via calcaneal tendon

A:

• plantarflexion

• inversion

• knee flexion

Soleus

O: head and proximal shaft of fibula

I: calcaneus via calcaneal tendon

A: plantarflexion

Tibialis Anterior

O: lateral condyle and proximal shaft of tibia

I: metatarsal and cuneiform

A:

• dorsiflexion

• inversion of foot

Serratus Anterior

O: ribs 1 through 9

I: vertebral border of scapula

A: protracts scapula

Pectoralis Minor

O: ribs

I: coracoid process of scapula

A: protracts and depresses scapula

Trapezius

O: occipital bone and thoracic vertebrae

I: clavicle and scapula

A: elevates scapula

Pectoralis Major

O: sternum, clavicle, costal cartilages

I: greater tubercle, intertubercular groove of humerus

Action: flexes and adducts shoulder

Latissimus Dorsi

I: intertubercular groove of humerus

A: extends and adducts arm

Deltoid

O: clavicle and scapula

I: deltoid tuberosity of humerus

A: abducts arm

Supraspinatus

G: Moves the arm; rotator cuff muscle

O: supraspinous fossa of scapula

I: greater tubercle of humerus

A: abducts arm

Infraspinatus

O: infraspinous fossa of scapula

I: greater tubercle of humerus

A: lateral rotation of shoulder

Teres Major

O: inferior angle of scapula

I: intertubercular groove of humerus

A: extends and adducts arm

Teres Minor

O: lateral border of scapula

I: greater tubercle of humerus

A: lateral rotation of shoulder

Subscapularis

G: Moves the arm; rotator cuff muscle

O: subscapular fossa of scapula

I: lesser tubercle of humerus

A: medial rotation of shoulder

Biceps Brachii

O: scapula

I: radial tuberosity

A:

• flexes arm at elbow

• supination

Triceps Brachii

O: humerus, infraglenoid tubercle of scapula

I: olecranon of ulna

A: extends arm at elbow

Brachialis

O: distal humerus

I: ulna

A: flexes arm at elbow

Brachioradialis

O: lateral epicondyle of humerus

I: styloid process of radius

A: flexes arm at elbow

Pronator Teres

O: medial epicondyle of humerus

I: radius

A: pronation

Flexor Carpi Radialis

O: medial epicondyle of humerus

I: metacarpals

A: flexes wrist

Flexor Carpi Ulnaris

O: medial epicondyle of humerus

I: carpals and metacarpals

A: flexes wrist

Palmaris Longus

O: medial epicondyle of humerus

I: palmar aponeurosis

A: flexes wrist

Flexor Pollicis Brevis

O: radius

I: phalanx of thumb

A: flexes thumb

Extensor Carpi Radialis

O: lateral epicondyle of humerus

I: metacarpals

A: extends wrist

Extensor Carpi Ulnaris

O: lateral epicondyle of humerus

I: metacarpals

A: extends wrist

Extensor Digitorum

O: lateral epicondyle of humerus

I: phalanges

A: extends wrist and fingers

Frontalis

O: galea aponeurotica

I: skin of eyebrows, bridge of nose

A: raises eyebrows

Orbicularis Oculi

O: medial edge of orbit

I: skin of eyelids

A: closes eye

Orbicularis Oris

O: maxilla and mandible

I: lips

A:

• compresses

• purses lips

Buccinator

O: alveolar processes of mandible and maxilla

I: orbicularis oris

A: compresses cheeks

Platysma

O: fascia covering the pectoralis major and deltoid muscles

I: mandible

A:

• tense neck

• depress mandible

• lower corners of mouth (frown)

Masseter

O: zygomatic arch

I: mandibular ramus

A: elevates mandible

Temporalis

O: temporal lines on parietal bone

I: coronoid process of mandible

A: elevates mandible

Sternocleidomastoid

O: manubrium of sternum, clavicle

I: mastoid process of temporal bone

A:

• together they flex the neck

• separately they bend the head to one side

Rectus Abdominis

O: pubis

I: costal cartilages and xiphoid process

A: flexes vertebral column

External Oblique

O: ribs

I: linea alba and iliac crest

A: compresses abdomen, flexes spine

Internal Oblique

O: lumbodorsal fascia and iliac crest

I: ribs, xiphoid process, and linea alba

A: compresses abdomen, flexes spine

Transverse Abdominis

O: ribs, iliac crest, lumbodorsal fascia

I: linea alba and pubis

A: compresses abdomen

Splenius

Action:

• together they extend the neck

• separately they rotate the head side-to-side

Erector Spinae Group

The 3 muscles:

1. Iliocostalis

2. Longissimus,

3. Spinalis

A: extend the vertebral column

Iliocostalis

G: Erector spinae

A: extends vertebral column

Longissimus

G: Erector spinae

A: extends vertebral column

Spinalis

G: Erector spinae

A: extends vertebral column

Flexors of the Wrist/forearm

Muscles in this group:

1. Flexor carpi radialis

2. Flexor carpi ulnaris

3. Palmaris longus

4. Flexor pollicis brevis

O: medial epicondyle of humerus

A: flex the wrist (and thumb)

Extensors of the Wrist/forearm

Muscles in this group:

1. Extensor carpi radialis

2. Extensor carpi ulnaris

3. Extensor digitorum

O: lateral epicondyle of humerus

A: extend the wrist (and fingers)

Iliopsoas group

Muscles: Psoas major + Iliacus

Moves: the thigh

A: flexion at hip

Adductor group

Muscles on test:

1. Gracilis

2. Adductor magnus

3. Adductor longus

Moves: the thigh

Action: adduction at hip

Gluteal group

Muscles:

1. Gluteus maximus

2. Gluteus medius

3. Tensor fasciae latae

Moves: the thigh

Quadriceps femoris group

Muscles:

1. Rectus femoris

2. Vastus medialis

3. Vastus intermedius

4. Vastus lateralis

A: extend the knee

I: tibial tuberosity via patellar ligament

Hamstrings group

Muscles:

1. Biceps femoris

2. Semitendinosus

3. Semimembranosus

O: ischial tuberosity

A: flex the knee, extend the hip

I: sciatic nerve

Rotator cuff muscles

1. Supraspinatus

2. Infraspinatus

3. Teres minor

4. Subscapularis

Moves: the arm/shoulder

Origin

The attachment site of a muscle on a bone

Does not move during contraction

Usually proximal to the insertion

Insertion

The specific site on the bone that does move during contraction

In some cases origin and insertion may interchange if the muscle can do more than one action

Action

The specific movement that results from muscle contraction at an articulation

Must state the direction of movement and the body part moved

(e.g., "flexion of the thigh")

Prime Mover (Agonist)

The main muscle involved in a specific movement

Antagonist

Muscles that have opposite actions

Typically found on the opposite side of the body part to the agonist

Synergist

Muscles that assist the prime mover, either by providing additional force or by stabilizing a joint so the prime mover can work more effectively

Fixator

A synergist that stabilizes a joint

Tendons

Connective tissue that attaches muscle to bone

Aponeuroses

Broad, flat sheets of connective tissue that attach muscles

(e.g., palmar aponeurosis, galea aponeurotica)

Angular movement

The angle between two articulating bones changes

Rotational movement

A bone rotates around an axis

Flexion

Decreases the angle between two bones

Extension

Increases the angle between two bones

Hyperextension

Extension beyond the normal anatomical position

Abduction

Movement away from the midline

Adduction

Movement toward the midline

Protraction

Moving a body part anteriorly (forward)

Retraction

Moving a body part posteriorly (backward)

Elevation

Moving a body part superiorly (upward)

Depression

Moving a body part inferiorly (downward)

Plantarflexion

Pointing the toes downward (foot moves away from the shin)

Dorsiflexion

Pulling the toes up toward the shin

Inversion

Turning the sole of the foot medially

Eversion

Turning the sole of the foot laterally

Circumduction

Circular movement of a limb (combination of flexion, abduction, extension, and adduction)

Rotation

A bone turns around its own long axis

Pronation

Rotating the forearm so the palm faces posteriorly/down

Supination

Rotating the forearm so the palm faces anteriorly/up

Muscle naming: Location

gluteus maximus, temporalis, brachialis

Muscle naming: Relative position

external and internal obliques

Muscle naming: Shape

deltoid and trapezius

Muscle naming: Size

pectoralis major and pectoralis minor