gross anatomy of muscle
TRANSCRIPT
GROSS ANATOMY OF MUSCLE
BODY MOVEMENTS
• MUSCLES ARE ATTACHED TO BONE OR CONNECTIVE TISSUE AT NO LESS THAN 2 POINTS
• ORIGIN – ATTACHED TO THE IMMOVABLE OR LESS MOVABLE BONE
• INSERTION – ATTACHED TO THE MOVABLE BONE
• DURING CONTRACTION THE INSERTION MOVES TOWARD THE ORIGIN
TYPES OF BODY MOVEMENTS
• FLEXION –DECREASES ANGLE BETWEEN BONES
• EXTENSION –INCREASES ANGLE BETWEEN BONES
• HYPEREXTENSION –GREATER THAN 180 DEGREES
• http://www.zoology.ubc.ca/~biomania/tutorial/mvmt/mv02.htm
• ABDUCTION –MOVE AWAY FROM THE MIDLINE
• ADDUCTION –MOVE TOWARD MIDLINE
• http://www.zoology.ubc.ca/~biomania/tutorial/mvmt/mv02.htm
• ROTATION –MOVEMENT OF BONE AROUND A LONGITUDINAL AXIS
• CIRCUMDUCTION –PROXIMAL END STATIONARY WHILE DISTAL END MOVES IN A CIRCLE
• http://www.zoology.ubc.ca/~biomania/tutorial/mvmt/mv02.htm
• PRONATION – MOVING HAND FROM ANTERIOR TO POSTERIOR POSITION (RADIUS OVER ULNA)
• SUPINATION – HAND FROM POSTERIOR TO ANTERIOR (RADIUS AND ULNA PARALLEL)
• INVERSION – SOLE OF FOOT TURNED MEDIALLY
• EVERSION – SOLE OF FOOT TURNED LATERALLY
• DORSIFLEXION –INSTEP OF FOOT MOVED UP TOWARD SHIN (STANDING ON HEELS)
• PLANTAR FLEX –TOES POINTED DOWNWARD
CRITERIA FOR NAMING MUSCLES
• DIRECTION OF MUSCLE FIBERS– RECTUS –
STRAIGHT– OBLIQUE -
DIAGONALLY
• RELATIVE SIZE– MAXIMUS –
LARGEST– MINIMUS –
SMALLEST– LONGUS – LONGEST– BREVIUS - SHORT
• LOCATION –ASSOCIATION WITH BONE– FRONTALIS– TEMPORALIS
• NUMBER OF ORIGINS– BICEPS – 2 – TRICEPS – 3– QUADRACEPS - 4
• LOCATION OF ORIGIN & INSERTION- STERNOCLEIDOMASTOID
- ORIGIN ON STERNUM & CLAVICLE AND INSERTS ON MASTOID PROCESS
• SHAPE OF MUSCLE– Deltoid – triangular– Trapezius
• ACTION OF MUSCLE– Adductor– Abductor– Extensor– Flexor
HEAD & FACIAL MUSCLES
• Frontalis – covers frontal bone; raises eyebrows & wrinkles forehead
• Temporalis – fan shaped; covers temporal bone; chewing muscle
• Orbicularis Oculi – circular muscle around the eye; close, squint, blink & wink eye
• Orbicularis Oris – circular muscle around mouth; kissing muscle; closes mouth & protrudes lips
http://www.gwc.maricopa.edu/class/bio201/head/head1b.htm
• Buccinator – runs horizontally across the cheek; flattens cheek & holds food in place while chewing
• Zygomaticus – group of muscles that extending from corner of mouth to cheekbone; raises corners of mouth upward; smiling muscle
• Masseter – covers the angle of mandible; closes jaw by elevating mandible
http://www.gwc.maricopa.edu/class/bio201/head/head1b.htm
Neck & Trunk Muscles• Platysma – single sheet - like muscle
covering anterolateral neck; superficial to sternocleidomastoid; pulls the corners of mouth inferior
• Sternocleidomastoid – 2 headed muscle (sternum & clavicle); heads fuse as they insert into mastoid process; bend head to shoulder & bows head
• Pectoralis Major – superficial upper chest muscle; adducts & flexes the arm
• Intercostal muscles –deep muscles between the ribs
• Raise rib cage for inhaling & depresses rib cage for exhaling
• 2 sets – internal & external
• Rectus Abdominis – paired muscles; most superficial of abs; flexes vertebral column, compressed abdomen during defecation & childbirth
• External Obliques – paired muscles on lateral wall of abdomen; flex & rotate vertebral column
• Internal Obliques – deep to external; flex & rotate vertebral column
• Transversus Abdominis – deepest layer; runs horizontal; compress abdominal contents
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• Trapezius – diamond or kite shaped; extends neck & adducts scapula
• Latissimus dorsi – covers lower back; extends & adducts humerus
• Erector Spinae – composed of 3 columns– Longissimus– Iliocostalis– Spinalis
– http://www.gwc.maricopa.edu/class/bio201/muscle/musc14.htm
• 1. iliocostalis
• 2. longissimus• 3. spinalis
MUSCLES OF ARM
• Deltoid – triangular; forms rounded part of shoulder; arm abduction
• Biceps brachii – anterior upper arm; 2 heads on shoulder girdle; inserts into radial tuberosity; supinates & flexes arm
• Triceps brachii – posterior upper arm; 3 heads on shoulder girdle& humerus; inserts into ulna; extension of arm
• Flexor carpi radialis – flexes wrist & abducts hand
• Flexor carpi ulnaris – flexes wrist & adducts hand
• Flexor digitorum superficialis – flexes wrist & fingers
f. digitorum
• Extensor carpi radialis – extends wrist & abducts hand ; 2 – longus & brevius
• Extensor digitorum - extends wrist & fingers
• Extensor carpi ulnaris – extends & adducts wrist
• Brachioradialis – flexes forearm
e.c.radialisbrevius
e.c. radialis longus e.c. ulnaris
e. digitorumbrachioradialis
MUSCLES OF THE LEG
• Gluteus maximus – largest; extends & rotates thigh laterally; sciatic nerve present
• Gluteus medius – abducts & rotates thigh medially
• Gluteus minimus – deep to medius; abducts & rotates thigh laterally
• Iliopsoas – fusion of 2 muscles – psoasmajor & iliacus; runs from ilium to lesser trochanter; flexes hip; prevents falling backwards
• Adductor muscles – compose medial thigh; adduct thigh (press together)– A. longus– A. magnus– A. brevius
• Pectineus – crosses under sartorius; adducts & rotates thigh laterally
• Sartorius – most superficial; runs diagonally across thigh; weak thigh flexor
• Gracilis – innermost thigh muscle; flexes & adducts thigh
– http://www.gwc.maricopa.edu/class/bio201/muscle/leg1.htm
Quadriceps
• Rector femoris – straight fibers; origin on iliac crest; flexes thigh & extends leg
• Vastus lateralis – “large lateral”• Vastus medialis – “large medial”• Vastus intermedialis – “large middle”; deep
to rector femoris*Extend leg; origin on femur & join to patellar
ligament
HAMSTRING GROUP
• Biceps Femoris – flexes leg & extends thigh
• Semitendinosus – “1/2 tendon”; flexes leg & extends thigh
• Semimembranosus – “1/2 membrane”; flexes leg & extends thigh
1 & 2 - Long & Short heads of Bicep Femoris3 – semitendinosus4 - semimembranosus
• Gastrocnemius – originates at base of femur & inserts into calcaneous via Achilles tendon; plantar flexion
• Soleus – deep &inferior to gastrocnemius; plantar flexion
• Tibialis Anterior – superficial muscle of the anterior lower leg; inversion & dorsiflexion
• Peroneus muscles – lateral lower leg; eversion & plantar flexion; 3 – longus, brevius, tertius
Drill & Practice Sites
• http://media.pearsoncmg.com/bc/bc_marieb_ehap_8/activities/index.html
• http://www.wiley.com/college/apcentral/anatomydrill/
• http://www.mhhe.com/biosci/esp/2002_general/Esp/default.htm
• http://highered.mcgraw-hill.com/sites/0072919329/student_view0/chapter9/labeling_exercises.html#