Muscular Practical

Occipital belly

Occipitofrontalis

O: Occipital bone

I: galea aponeurosis

A: retracts scalp

Frontal belly

Occipitofrontalis

O: galea aponeurosis A

I: skin of forehead

A: moves scalp forward, raise eyebrows, wrinkles forehead

orbicularis oris

O: Modiolus

I: skin at corners of mouth

A: closes/protrudes lips, compresses lips against teeth

A

Levator labii superioris

O: maxilla

I: Orbicularis oris

A: Raises upper lip

Buccinator

O: maxilla and mandible

I: Modiolus and orbicularis oris

A: compresses cheeks, helps with blowing, sucking, chewing

Orbicularis oculi

O: frontal bone, frontal process of maxilla, lacrimal bone

I: skin of eyelid

A: closes eye

Levator palpebrae superioris

O: lesser wing of sphenoid

I: upper eyelid

A: raises upper eyelid

Superior rectus

O:

I:

A: elevates, adducts, inntorts (rotates eye toward nose)

lateral rectus

O:

I:

A: abbducts eye

medial rectus

O:

I:

A: adducts the eye

inferior rectus

O:

I:

A: depression, adducts, extorsion

Inferior oblique

O: maxillary orbit

I:

A: elevates, abducts, extorts eye

superior oblique

O:

I:

A: depresses, abducts, intorts

masseter

O: Maxilla and zygomatic arch

I: Angle and ramus of mandible

A: Elevates mandible (closes jaw)

temporalis

O: temporal bone

I: coronoid process and ramus of mandible

A: elevates and retracts mandible

Sternocleidomastoid

O: sternum (manubrium), Clavicle

I: temporal bone, mastoid process

A: Together: neck/head flexion. Alone: same-side lateral flexion, opposite-side rotation; assists sternum elevation (inhale)

scalenes

O: c2-c6

I: ribs 1-2

A: neck flexion (bending neck forward), same-side lateral flexion, opposite-side rotation; elevates ribs

rectus abdominis

O: pubic crest, pubic symphysis

I: sternum (xiphoid process), costal cartilage (5-7)

A: Flexes spine (regular crunch), Compresses abdomen (tightens abs for urination, etc.),

Reverse action: flexes pelvis (reverse crunch)

transverse abdominis

O: iliac crest, inguinal ligament, lumbar fascia, cartiladge of inferior 6 ribs

I: Internal oblique aponeurosis, xiphoid, linea alba, pubis

A: Compresses abdomen

external abdominal oblique

O: Ribs 5-12

I: Iliac crest, pubis, linea alba

A: Both sides: Flexes vertebral column and compresses abdomen

One side: Bends trunk toward same side (lateral flex) and rotates vertebral column toward opposite side.

internal abdominal oblique

O: Iliac crest, Inguinal ligament, Thoracolumbar fascia

I: Costal cartilage 9-12-4 ribs, Linea alba

A: Bilaterally – compress abdomen & flex vertebral column

Unilaterally – lateral flex & rotate vertebral column

diaphragm

O: Xiphoid, costal cartilages/ribs 6–12, L1–L3

I: Central tendon

A: Contraction flattens diaphragm for inhalation; relaxation assists exhalation

External intercostals

O: Inferior borders of ribs 1–11

I: Superior borders of ribs 2–12

A: Elevates ribs; increases thoracic volume during inhalation

Internal intercostals

O: Inferior borders of ribs/costal cartilages 1–11

I: Superior borders of ribs 2–12

A: Draws ribs together; decreases thoracic volume during forced exhalation

Spinalis

•Capitis, cervicis, thoracis

O:

I:

A: Both sides: head extension. One side: lateral flexion and opposite-side rotation

ilocostalis

•illocostalis cervicis, intercostalis thoracis

O:

I:

A: Extends, laterally flex, and rotates the vertebral column

Longissimus

O:

I:

A: Extension and lateral rotation

subclavius

O: 1st rib

I: clavicle

A: Depresses and moves clavicle anteriorly; stabilizes pectoral girdle

Serratus anterior

O: Ribs 1–9

I: Costal surface, medial border of scapula

A: Scapular abduction/protraction and upward rotation; stabilizes scapula; reverse action elevates ribs

trapezius

O: External occipital protuberance, nuchal ligament, C2–T2

I: Clavicle, acromion, scapula

A: superior: elevation, head extension/lateral flexion. Middle: retraction. inferior: depression. superior + inferior: upward rotation of scapula

levator scapulae

O: transverse processes of c1-c4

I: Superior angle and medial border of scapula

A: Elevates scapula; retracts shoulder

Rhomboid major

O: Spinous processes T2–T5

I: Medial scapular border below spine

A: Elevates, retracts, downwardly rotates, stabilizes scapula

Rhomboid Minor

O: Spines of 7^th cervical & 1^st thoracic vertebrae

I: Vertebral boarder of scapula inferior to the spine

A: Elevates, retracts, downwardly rotates, stabilizes scapula

Pectoralis major

O: Clavicle, sternum, costal cartilages 1–6

I: Bicipital groove of humerus

A: Shoulder adduction, IR; extension from flexed position; flexion from extended position

Pectoralis major

O: Clavicle, sternum, costal cartilages 1–6

I: Bicipital groove of humerus

A: Shoulder adduction, internal rotation of humerus; extension from flexed position; flexion from extended position

Latissimus dorsi

O: T7–T12 spinous processes, iliac crest, ribs 9–12

I: intertubercular groove of humerus

A: Shoulder extension (bring humerus back), adduction, Internal rotation of humerus

Supraspinatus

O: Supraspinous fossa

I: Greater tubercle

A: Initiates abduction of humerus; stabilizes humeral head

Infraspinatus

O: Infraspinous fossa

I: Greater tubercle

A: external rotation of humerus, stabalizes humeral head

teres minor

O: Lateral border of scapula

I: Greater tubercle

A: External rotation of humerus; assists adduction and extension; stabilizes humeral head

Subscapularis

O: Subscapular fossa

I: Lesser tubercle

A: Internal rotation of humerus

Deltoid

O: Anterior: lateral clavicle; middle: acromion; posterior: scapular spine

I: Deltoid tuberosity

A: Anterior: flexion, AB, horizontal AD, IR. Middle: AB. Posterior: extension, AD, horizontal AB, ER of humerus

teres major

O: Inferior angle of scapula

I: intertubercular sulcus

A: Shoulder extension; assists adduction and IR

Coracobrachialis

O: Coracoid process

I: Middle of medial humeral shaft

A: Shoulder flexion and adduction of humerus

Biceps brachii

O: Long head: tubercle above glenoid; short head: coracoid process

I: Radial tuberosity

A: Elbow and shoulder flexion; forearm supination

Brachialis

O: Distal anterior humerus

I: Ulnar tuberosity and coronoid process

A: Elbow flexion

Brachioradialis

O: Lateral distal humerus

I: Radius, proximal to styloid process

A: Elbow flexion

Triceps brachii

O: Long: infraglenoid tubercle; lateral and medial: posterior humerus

I: Olecranon

A: Extends forearm at elbow (all heads).

• Extends humerus at shoulder (long head).

• Adducts humerus at shoulder (long head).

Pronator teres

O: Medial epicondyle and coronoid process

I: Radius

A: Forearm pronation; assists elbow flexion

Supinator

O: Lateral epicondyle and ulna

I: Lateral radius

A: Forearm supination

Flexor carpi radialis

O: Common flexor tendon, medial epicondyle

I: Metacarpals 2–3

A: Wrist flexion, radial deviation (move hand towards thumb); assists elbow flexion

Flexor carpi ulnaris

O: Common flexor tendon, medial epicondyle

I: Pisiform, hamate, base of metacarpal 5

A: Wrist flexion, ulnar deviation (move hand towards pinky); assists elbow flexion

Palmaris longus

O: Medial epicondyle

I: Flexor retinaculum, palmar aponeurosis

A: Wrist flexion

Flexor digitorum superficialis

O: Common flexor tendon, medial epicondyle

I: Middle phalanges of digits 2–5

A: Finger flexion 2–5

Flexor digitorum profundus

O: Anteromedial ulna

I: Distal phalanges of fingers 2–5

A: Wrist and finger flexion 2–5

Flexor pollicis longus

O: Anterior radius, interosseous membrane

I: Distal phalanx of thumb

A: Thumb flexion

Extensor carpi radialis longus

O: Lateral supracondylar ridge of humerus

I: Metacarpal 2

A: Wrist extension, radial deviation

Extensor carpi radialis brevis

O: Common extensor tendon, lateral epicondyle

I: Metacarpal 3

A: Wrist extension, radial deviation

Extensor digitorum

O: Common extensor tendon, lateral epicondyle

I: Fingers 2–5

A: Wrist and finger extension 2–5

Extensor digiti minimi

O: Common extensor tendon, lateral epicondyle

I: Little finger

A: Little-finger extension

Extensor carpi ulnaris

O: Common extensor tendon, lateral epicondyle

I: Base of metacarpal 5

A: Wrist extension, ulnar deviation (towards pinky)

Extensor pollicis brevis

O: Radius and interosseous membrane

I: Proximal phalanx of thumb

A: Proximal thumb phalanx extension

Extensor pollicis longus

O: Ulna and interosseous membrane

I: Proximal thumb phalanx (as stated in slide)

A: Thumb extension and abduction

Extensor indicis

O: Posterior ulna

I: Index finger extensor digitorum tendon

A: Index finger extension

Abductor pollicis brevis

O: Not provided

I: Not provided

A: Abducts thumb

Opponens pollicis

O: Not provided

I: Not provided

A: Thumb opposition

Flexor pollicis brevis

O: Not provided

I: Not provided

A: Flexes thumb

O: Not provided

I: Not provided

A: Adducts thumb

Abductor digiti minimi

O: Not provided

I: Not provided

A: Abducts little finger

Flexor digiti minimi brevis

O: Not provided

I: Not provided

A: Flexes little finger

Opponens digiti minimi

O: Not provided

I: Not provided

A: Little-finger opposition

Palmar interossei

O: Not provided

I: Not provided

A: Finger adduction and MCP flexion; IP extension

Dorsal interossei

O: Not provided

I: Not provided

A: Abduct digits 2–4; MCP flexion; IP extension

Iliacus

O: Iliac fossa and sacrum

I: Lesser trochanter

A: Hip flexion and abduction; trunk flexion

Psoas major

O: T12–L5

I: Lesser trochanter

A: Hip flexion and abduction; trunk flexion

Gluteus maximus

O: Posterolateral ilium

I: Gluteal tuberosity, IT band, linea aspera, greater trochanter (as listed)

A: Hip extension, abduction, ER; assists knee stabilization

Gluteus medius

O: Ilium

I: Greater trochanter

A: Hip extension, abduction, medial rotation

Gluteus minimus

O: Ilium

I: Greater trochanter

A: Hip extension, abduction, medial rotation

O: Iliac crest

I: Iliotibial band

A: Hip abduction, ER, flexion

Piriformis

O: Anterior sacrum

I: Greater trochanter

A: Hip lateral rotation and abduction

Adductor longus

O: Pubis

I: Linea aspera of femur

A: Hip adduction/flexion; rotation varies with position; reverse action hip extension

Adductor brevis

O: Pubis

I: Linea aspera of femur

A: Hip adduction/flexion; rotation varies with position; reverse action hip extension

Adductor magnus

O: Pubis and ischium to ischial tuberosity

I: Linea aspera of femur

A: Hip adduction; rotation varies; anterior portion flexes hip, posterior extends hip

Pectineus

O: Superior pubic ramus

I: Linea aspera (as listed)

A: Hip flexion and adduction

Gracilis

O: Pubis

I: Medial tibia

A: Hip adduction and medial rotation; knee flexion

Rectus femoris

O: Straight head: AIIS; oblique head: acetabulum

I: Patella by quadriceps tendon, then tibial tuberosity by patellar ligament

A: Knee extension and hip flexion

Vastus lateralis

O: Greater trochanter of femur

I: Tibial tuberosity via patella and tendon

A: Knee extension

Vastus medialis

O: Linea aspera of femur

I: Tibial tuberosity via patella and tendon

A: Knee extension

Vastus intermedius

O: Femoral shaft

I: Tibial tuberosity via patella and tendon

A: Knee extension

Sartorius

O: ASIS

I: Medial tibia

A: Hip/knee flexion; hip abduction and ER

Biceps femoris

O: Long head: ischial tuberosity; short head: linea aspera

I: Head of fibula, lateral tibial condyle

A: Hip extension, knee flexion; ER of flexed knee (slide 32)

Semitendinosus

O: Ischial tuberosity

I: Medial tibial shaft

A: Hip extension, knee flexion; IR of flexed knee (slide 32)

Semimembranosus

O: Ischial tuberosity

I: Medial tibial condyle

A: Hip extension, knee flexion; IR of flexed knee (slide 32)

Tibialis anterior

O: Lateral tibial condyle/shaft and interosseous membrane

I: First metatarsal and medial cuneiform

A: Dorsiflexion and inversion

Extensor hallucis longus

O: Fibular shaft and interosseous membrane

I: Distal phalanx of great toe

A: Great-toe extension and dorsiflexion

Extensor digitorum longus

O: Lateral tibial condyle, fibular shaft, interosseous membrane

I: Lateral four toes

A: Extension of toes 2–5, dorsiflexion

Fibularis (peroneus) tertius

O: Distal third of fibula and interosseous membrane

I: Base of fifth metatarsal

A: Dorsiflexion and eversion

Fibularis (peroneus) longus

O: Fibular shaft

I: First metatarsal and medial cuneiform

A: Plantarflexion and eversion

Fibularis (peroneus) brevis

O: Fibular shaft

I: Base of fifth metatarsal

A: Plantarflexion and eversion

Gastrocnemius

O: Medial and lateral femoral condyles

I: Calcaneus via Achilles tendon

A: Plantarflexion, knee flexion

Soleus

O: Tibial soleal line and fibular head

I: Calcaneus via Achilles tendon

A: Plantarflexion

Tibialis posterior

O: Tibial/fibular shafts, interosseous membrane

I: Navicular, cuneiforms, cuboid, calcaneus, metatarsals 2–4

A: Plantarflexion and inversion