OBU A&P1 Muscles (Lecture)

Occipitofrontalis

raises eyebrows and wrinkles forehead

orbicularis occuli

around eyes

closes eyes

levator palebrae

opens eyes

levator labii superioris

First bicycle spoke

Raises upper lip

levator anguli oris

Elevates the corners of the mouth

zygomaticus major

(blue)

Angled bicycle spoke

Smile muscles

Major is thicker and more inferior

originates on zygomatic bone

zygomaticus minor:

Angled bicycle spoke

Smile muscles

Major is thicker and more inferior

originates on zygomatic bone

risorius:

Most lateral of mouth muscles

Means laughter

Pulls corners of mouth backward (laterally)

depressor Labil inferioris

Depresses lower lip

depressor anguli oris

Pulls down corner of the mouth

Procerus

Frowning face

Nasalis

Wrinkles nose

orbicularis oris

closes and purses the lips

Masseter

originates on Zygomatic bone

inserts on ramus

elevates mandible

Buccinator

Deep to the masseter

Trumpetor

Tense cheeks during chewing

sucking

whistling

Temporalis

Side of head

aids in chewing

Works with masseter

Underneath zygomatic arch

elevates mandible

pterygoid muscle

Medial to temporalis

Chewing muscles

Side to side movement of jaw

what are the 4 chewing muscles

masseter, temporalis, pyterygoid (2)

Genioglossus

controls tongue

styloglossus

Manipulating tongue and swallowing

Originates on styloid process

Inserts on tongue

Pharyngeal contstrictors

connect nasal cavity and esophagus

Wraps around pharynx

Pushes food down into esophagus

Platysma

Flat sheet that covers the front of the neck

pulls down the corners of the mouth and lowers the jaw

depresses mandible

Sternocleidomastoid

origin: sternum and clavicle

insertion: mastoid process

flexes and rotates neck

Trapezius

inserts on spine of scapula

Extends neck

Multiple actions - Elevation, Adduction, Depression

Semispinalis capitis

Inserts on skull

extends neck

splenius capitus

Inserts on skull

turns head side to side "no"

erector spinae group

Deep muscle proximal to vertebral column

maintaining posture

extends spinal column

quadratus lumborum

Connects from lowest rib to illium

extension and pelvic stability

rectus abdominus

Flex vertebral column

Parallel muscles from thoracic cage to pubic bones

Linea alba separates rights and left (white line)

Apposes erector spinae

what is the order of the abdominus/obliques

External, internal, transversus (order)

transversus abdominus

Parallel to the ground

Compress abdomen

Pooping and child birth

external oblique

Compress underlying structures

slant Down and toward midline

Right external works with left internal to produce rotation

Right rotates left

Antagonized by left external oblique or right internal oblique

internal oblique

Rotation

Perpendicular

Right rotates right

Diaphragm

Breathing

Origin: Inferior border of ribcage

Innervated by the phrenic nerve

pushes abdomen down

scalene

Elevate ribcage

Inhalation

Brachial plexus emerges between anterior and middle

external intercostals

Down and inward orientation

Respiration

raise a spread ribs

internal intercostals

Up and in orientation

Respiration

forced expiration

levator scapulae

Scapular elevation

pectoralis minor

flexes, adducts, medial rotation

rhomboid major

Origin: under trapezius

Inserts: medial border of scapula

elevates and adducts

Rhomboid minor

Origin: under trapezius

Inserts: medial border of scapula

elevates and adducts

serratus anterior

Attaches to Inferior angle of scapula

Produces scapular protraction

rotates

subclavius

Connects rib 1 to bottom of clavicle

depresses scapula

pectoralis major

Origin: sternum

Insertion: proximal humerus (push up muscles)

Horizontal adduction

and flex shoulder

deltoid

Origin: spine of scapula and lateral side of clavicle

Insertion: deltoid tuberosity

Flexion, extension, abduction of shoulder

latissimus dorsi

Origin: from spinous process of thoracic region

insertion: front of humerus

Powerful muscle

extends, adducts, medial rotation

subscapularis

internal rotation

supraspinatus:

Rotator cuff muscle

0 to 15 degrees of abduction

infraspinatus

external rotation

teres minor

Lateral rotation

Minor on top

teres major

Major on bottom

Goes through armpit and attaches to front of humerus

Medial rotation, extends, adducts

SITS muscles

act on humerus (supraspinatus, infraspinatus, teres minor, subscapularis)

biceps brachi

origin: scapula

Insertion: radius

Innervation: muscular cutaneous nerve

Crosses shoulder joint and elbow joint

Flexation and supination

coracobrachialis

Origin: coracoid

Insertion: humerus

Acts on humerus

Sinergizes with interior belly of detolid

Flection of shoulder

adduction

brachialis

Flexion at elbow

triceps brachii

extension of elbow

Superficial muscles of the forearm

(PFPF)

Flex wrist

pronator teres, flexor carpi radialis, Palmaris longus, flexor carpi ulnaris)

pronator teres

pronates forearm

flexor carpi radialis

flex wrist

Palmaris longus

not in all humans, flex wrist

flexor carpi ulnaris

Flexes wrist

flexor digitorum superficialis

Flexes digits (not tips)

flexor digitorum Profundis

Flexes finger tips

flexor policis longus

Flexes thumb

Forearm muscles that act at the elbow

Ancones, Brachioradialis, Supinator

Forearm muscles that act on wrist

Extensor carpi radialis longus

Extensor carpi ulnaris

Extensor carpi radialis longus brevis

Extensor carpi radialis longus

wrist extension

Extensor carpi ulnaris

Antagonizes flexor carpi ulnaris

Extensor carpi radialis brevis

extends wrist

what three forearm muscles act on the digits

extensor digitorum

Extensor Digiti minimi

Extensor indicis

Retinaculum

Holds hand muscles in place

What are the gluteus muscles

gluteus maximus, gluteus medius, gluteus minimus, iliotibial tract, tensor fasciae latte

gluteus maximus

Origin: liliac spine

Insertion: posterior of femur

Rotates and extends femur/hip

gluteus medius

Most lateral

Abduction of hip

medial rotation

Helps in walking

Insertion: greater trochanter

gluteus minimus

Hip abduction

lateral rotation

Iliotibial tract

IT band

origin: hip

insertion: tibia

stabilization

tensor fasciae latte

Front of hips

Tenses IT band to lock the knee in extension

abducts and medially rotates

Insertion: iT band

What are the lateral rotators

piriformis, quadratura femoris

piriformus

Pear shape

Rubs on sciatic nerve sometimes

Insertion greater trochanter

Externally rotates hip

Deep to gluteus medias

quadrates femoris

lateral hip rotation

what are the adductors and how are they innervated

pectinous, adductor longs, adductor brevis, adductor Magnus, gracilis (obturator nerve)

pectinous

Origin: on pelvic bone

More flexion than adduction

medial rotation

Medial to iliopsoas

adductor longus

hip adduction

adductor brevis

hip adduction

aductor Magnus

hip adduction

gracillis

hip adduction

flexes knee

Iliopsoas

running muscles

Major hip flexors

what are the 4 knee extenders and what innervates them

rectus femoris, vastus lateralis, vastus medials, vastus intermedius (femoral nerve)

rectus femoris

insertion: patellar tendon

top

crosses hip and knee joints

knee extension

vastus lateralis

knee extension

vastus medialis

Fibers are diagonal

Pulls and keeps patella medially located

knee extension

vastus intermedias

knee extension

sartorius

Longest

Origin: iliac spine

Insertion: tibia

Taylors muscle

Laterally divides quads

External rotation and flexation

what are the flexors of the knee and what innervates them

biceps femoris, semimembranous, semitendinosus (sciatic nerve)

biceps femoris

Lateral side

insertion: fibula

knee flexion

semimembranosus

Medial

Behind semitendinosus

knee flexion

semitendinosus

Medial

On top of Semimembranosus

Round

knee flexion

posterior compartment

gastrocnemius, soleus

gastrocnemius

Plantar flection of ankle

Insertion: calcaneal tendon

Runing and jumping

soleus

Deep to gastrocnemius

looks like a fish

Walking muscle

Plantar flection

Inserts onto calcaneal tendon