Download Anatomy Unit 10 Notes

Muscle Action
Unit 10
1
Points of Attachment
1. The type of movement produced by a skeletal muscle depends on
________________________________________________.
2. There are approximately _______ skeletal muscles
3. Origin =
* the head of the muscle
* some muscles have more than one (ex. Biceps - 2 heads)
4. Insertion =
* the insertion is ____________________________
* sometimes they switch roles
** ex. Pectoralis Major - connects the humerus to the thorax
(1) arm flexion...O=thorax; I=humerus
(2) chin-ups...O=humerus; I=thorax
* ___________________ is the portion found between the O & I....
referred to as the meat of the muscle....usually covers the
______________________
Interaction of Skeletal Muscles
1. Skeletal muscles almost always function in groups rather than singly
2. Prime Mover =
ex. Biceps Brachii.....flexion at the elbow
3. Antagonist =
ex. Triceps Brachii.....extension at the elbow
* they usually __________ while the PM contracts
* can also resist the movement of the PM
4. Synergist =
* they help by holding a part steady or actually aiding in the
movement
5. Reciprocal Innervation =
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Superficial Muscles
1. Reasons for Names:
a)
Pectoralis Major
b)
Deltoid; Quadratus
c)
Sternocleidomastoid; Tibialis Anterior
d)
Extensor Digitorum; Adductor Longus
e)
Biceps Brachii; Triceps Brachii
f)
External Oblique
2. Review Muscle Action Terminology (Handout)
Muscles of Facial Expression and Mastication
1. Epicranius
(L) covers the _________ & the _________....composed of the
occipitalis (origin) and frontalis (insertion); separated by the
epicranial aponeurosis
(A)
2. Orbicularis oculi
(L)
(A) closes the eye (squinting; blinking; compressing tear gland)
3. Orbicularis oris
(L) encircles the __________
(A)
4. Buccinator
(L) lateral to orbicularis oris
(A) flattens cheeks (whistling; blowing trumpet)
5. Zygomaticus
(L) extends from ____________ to orbicularis oris (corner of mouth)
(A)
6. Platysma
(L) lower border of ____________ to sternum & clavicle
(A) lowers mandible; draws edges of mouth down (pouting)
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7. Temporalis
(L)
(A) closes jaw (chewing)....a synergist
8. Masseter
(L) zygomatic arch to lower border of _____________
(A)
Muscles that Move the Head
1. Result from the actions of paired muscles in the neck and upper back....
responsible for ________________________________________.
2. Sternocleidomastoid
(L) _________________ of skull to clavicle & sternum (both sides)
(A) neck (head) flexion (both sides contract); lateral neck flexion
3. Splenius Capitis
(L) mastoid process to _________________ of lower cervical & upper
thoracic vertebrae
(A) head rotation; __________________; head extension
....QUIZ #1....
Muscles of the Pectoral Girdle/Upper Arm
1. Trapezius
(L) base of skull/cervical & thoracic vertebrae (origin) to the
_____________________ (insertion)
(A) adducts _______ (pulls it back & down); raises scapula (shrugging);
_________________
* provides the leverage for thrusting the arm forward as in
shot-putting
2. Serratus Anterior
(L) fleshy, narrow strips covering ______ (origin) to scapula (insertion)
(A) pulls scapula forward and downward (for pushing heavy objects)
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3. Pectoralis Major
(L) clavicle/sternum (origin) to ________ (insertion)....[covers the chest]
(A) arm ________; arm adduction; arm ________ (aka: medial rotation)
4. Latissimus Dorsi
(L) lower thoracic/upper lumbar vertebrae (o) to _______________ (i)
(A) arm extension; arm _________; arm pronation (pulls arm down &
back.....known as the most “powerful pulling muscle”)
5. Teres Major
(L) lateral border/inferior angle of scapula (o) to upper humerus (i)
* directly above LD
(A) arm ___________; arm adduction; arm pronation
* a _____________ to the LD
6. Infraspinatus
(L) scapula (o) to ____________ (i)
* in-between teres major & trapezius
(A) arm adduction; arm __________ (aka: lateral rotation); synergist to
arm extension
7. Deltoid
(L) triangular muscle -- covers the ___________; scapula/clavicle (o) to
humerus (i)
(A) arm ____________; arm extension (posterior fibers);
arm flexion (anterior fibers)
Muscles of the Forearm/Wrist/Hand & Fingers
1. Biceps Brachii
(L) __________ upper arm - scapula (o) to radius (i)
(A) forearm flexion; ____________ of hand; flexion of hand
2. Triceps Brachii
(L) posterior upper arm - humerus/scapula (o) to __________ (i)
* the only muscle on the back of the upper arm!
(A) forearm _____________; arm extension
....QUIZ #2....
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3. Brachioradialis
(L) long band of muscle on upper part of forearm (thumb side) humerus (o) to radius(i)
(A) ___________ flexion (synergist to the biceps)
4. Flexor Carpi Radialis
(L) anterior forearm - medial to ________________ - medial/distal
humerus (o) to 2nd/3rd metacarpal (i)
(A) wrist flexion; wrist ______________
5. Pronator Teres
(L) __________ forearm - medial humerus and ulna (o) to lateral surface
of radius (i)
* in-between FCR and Brachioradialis
(A) forearm pronation; biceps ______________ (stabilizer)
6. Palmaris Longus
(L) anterior forearm - ____________ humerus (o) to palm fascia (i)
* medial to FCR
(A) wrist _____________
7. Flexor Digitorum
(L) _________ forearm - humerus/radius (o) to metacarpals/fingers (i)
* medial to PalmLong
(A) wrist flexion; ___________ flexion (middle/distal phalanxes)
8. Flexor Carpi Ulnaris
(L) anterior, most medial forearm - humerus/ulna (o) to carpals/
metacarpals (i)
* medial to FlexDig
(A) wrist ___________; wrist adduction
9. Extensor Carpi Radialis
(L) posterior forearm - lateral epicondyle of humerus (o) to
metacarpals (i)
* lateral to brachioradialis
(A) wrist extension; wrist ____________
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10. Extensor Digitorum
(L) posterior forearm - humerus (o) to phalanges (digits #2-5) (i)
* between ECR & ECU
(A) _____________ extension
11. Extensor Carpi Ulnaris
(L) ____________, medial forearm - humerus (o) to 5th metacarpal (i)
(A) wrist extension; wrist ______________
Muscles of the Abdominal Wall
1. External Oblique
(L) anterior, lateral abdomen - lower 8 ribs (o) to iliac crest (i)
(A) trunk flexion (forward); _______________ flexion; trunk rotation;
tenses abdominal wall; compression of abdominal organs
2. Rectus Abdominis
(L) ______________ abdomen - pubis (o) to sternum/ribs (i)
(A) trunk flexion; lateral trunk flexion; protects abdominal organs;
compression of abdominal organs
*** Linea Alba = tough band of connective tissue that covers this
muscle - serves as an attachment for some of the abdominal
wall muscles
....QUIZ #3....
Muscles of the Thigh
1. Quadriceps Femoris
(L) consists of ______ large muscles on ______ thigh - pelvis/femur (o)
to patella (i)
1] Rectus Femoris - thigh flexion
2] Vastus Lateralis
3] Vastus Intermedius - deep
4] Vastus Medialis
(A) lower leg _____________
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2. Sartorius
(L) long band of muscle - lateral ______ (o) -- crosses anterior thigh -- to
medial tibia (i)
(A) thigh flexion; thigh ________________; lower leg flexion
3. Gluteus Maximus
(L) ____________ pelvic region - ilium/sacrum/coccyx (o) to posterior
femur (i)
(A) thigh ____________; thigh lateral rotation
4. Gluteus Medius
(L) lateral ilium (o) to greater trochanter of femur (i) (short, thick
muscle on side of hip....gives it a rounded contour)
(A) _________ abduction; thigh medial rotation
5. Gracilis
(L) medial _________.....pubis (o) to medial _________ (i)
(A) thigh ___________; lower leg flexion; lower leg medial rotation
6. Pectineus
(L) anterior thigh.....pubis (o) to femur(i) (superior to adductor longus)
(A) thigh __________; thigh adduction
7. Adductor Longus
(L) anterior thigh.....pubis (o) to femur(i) (medial/inferior to pectineus)
(A) thigh _____________; thigh flexion; thigh lateral rotation
8. Tensor Fasciae Latae
(L) anterior, lateral thigh.....ilium(o) to thigh fascia (i)
(to the front & side of the hip)
(A) thigh abduction; thigh flexion; thigh __________________
9. Iliopsoas
(L) lateral/superior to pectineus.....lumbar vertebrae/ilium (o) to
lesser trochanter of femur (i)
** includes the psoas major and iliacus
(A) thigh ____________; thigh lateral rotation
....QUIZ #4....
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10. Biceps Femoris
(L) posterior/lateral thigh.....ischium/femur (o) to lateral tibia/fibula (i)
(A) thigh ___________; lower leg flexion; lower leg lateral rotation
11. Semitendinosus
(L) posterior/central thigh.....ischium (o) to medial tibia (i)
(A) thigh extension; ____________ flexion; lower leg medial rotation
12. Semimembranosus
(L) posterior/medial thigh.....ischium (o) to medial tibia (i)
(A) thigh extension; lower leg flexion; lower leg ________________
Muscles of the Lower Leg
1. Tibialis Anterior
(L) anterior/lateral lower leg.....lateral tibia (o) to _______________ (i)
(A) foot ______________; foot dorsiflexion
2. Extensor Digitorum Longus
(L) anterior/lateral lower leg.....tibia/fibula (o) to phalanges (i)
* lateral to TA
(A) foot _______________; foot dorsiflexion; toe extension
3. Peroneus Longus
(L) lateral lower leg.....lateral tibia/fibula (o) to metatarsals/tarsals (i)
* lateral to EDL
(A) foot eversion; foot _________________
4. Soleus
(L) borders ________________ medially & laterally.....tibia/fibula (o) to
calcaneus (i)
* it lies beneath the gastroc.!
(A) foot plantar flexion
5. Gastrocnemius
(L) posterior lower leg (calf muscle).....lateral/medial ____________ of
femur (o) to calcaneus (i)
(A) lower leg ______________; foot plantar flexion
6. Calcaneal (Achilles) Tendon
** large tendon connecting gastrocnemius to calcaneus
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Clinical Terms Related to the Muscular System
1. Convulsion
2. Muscular Dystrophy
3. Myasthenia Gravis
4. Paralysis
5. Shin Splints
....QUIZ #5....
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