Download Muscular System

Muscular System
Key medical root: “Myo”
Muscles
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Purpose
 We
have approx 600 muscles
 Provide movement of body by “lifting” the
bones
 Contribute to posture, produce body heat,
and protect human body
 They cover our entire body
 Where
there is a bone, there is a muscle(s) to
move it.
Basic Terminology
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Name of muscles come from the Latin language
Origin
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Insertion
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Place where the muscle begins
It is stationary (doesn’t move)
Place where muscle ends
This is the place where the muscle lifts that particular
bone
Antagonists
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Opposites
One muscle flexes a joint; another muscle extends it
Types of Muscle
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1) Skeletal
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Also called voluntary muscle
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2) Cardiac
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Why, they are the muscles we can consciously move.
They are the ones that move our bones
The heart is a muscle that beats/contracts
It is involuntary
3) Smooth
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Found on walls of blood vessels and intestines to
allow them to dilate and/or contract
They are involuntary.
Attachment to Bone
Ligaments- Rubber-band like
tissue that connects bone to bone,
typically to keep a joint in place
 Tendons- Rubber-band tissue that
connects bone to muscle
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Most famous tendons?
Achilles Tendon connects your
calcaneus (heel) bone to your
posterior calf muscles.
 Popliteal tendon
 Axillary Tendon
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Both tendons and ligaments are
white
 Both are avascular meaning they
don’t receive a lot of blood
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Therefore, slow to heal.
Biceps vs Triceps (Antagonist Group
#1)
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Bicep Brachii
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Flexes the elbow jt
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Origin-Scapula
Insertion-Radius
Tricep Brachii
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Extends the elbow jt
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Origin: Scapula
Insertion: Ulna
Vocabulary
To don (v) – to put something on
 To doff (v)- to take something of
 To besmirch (v)- to stain someone’s reputation
 To prevaricate (v)- to stray or evade from the truth; to lie
 To befuddle (v) befuddled (adj)- to confuse
 Enigma (n)- something/something that is puzzling, riddle-like,
or mysterious
 To propagate (v)- to spread or multiply
 Prerogative (n) – a special right or privilege given to a
person/organization
 To augment (v) – to make larger in size; to grow
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Abbreviations
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cxr- Chest X-ray
KUB- Abdominal X-ray
ASA- Aspirin
APAP – Acetaminophen (Tylenol)
BP – blood pressure
OS- left eye
OD- right eye
BS- blood sugar
gtt- drop (gtts-drops)
po – by mouth
Forearm
Muscles that Supinate/Pronate
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Pronator Teres
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Allows us to pronate the arm
(palm facing ground)
Supinator Muscle
Allows us to supinate (palm
facing up)
 Biceps does as well
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Note: Most muscles to move
your fingers are not in your
hand, but in your forearm.
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Tendons connect them to your
metacarpals and phalanges
Lifting the Arm from the Shoulder
Abduction/Adduction
Lifting the arm (at the shoulder
joint) requires the use of three
major muscles
 3 Prime Movers of Arm
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Deltoids
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Origin: Clavicle
Insertion: Humerus
Common site of injections/shots
Pectoralis Major
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Your “pecs”-large chest/breast
muscles
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Origin: Clavicle, Sternum, and
Ribs
Insertion: Humerus
Latissimus Dorsi
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Your “lats”-large muscle on your
MIDDLE BACK!
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Origin: Posterior Lower Ribs
Insertion: Humerus
Throwing Motion
Rotator Cuff Muscles
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To throw something, you
use your 4 Rotator Cuff
muscles
They are all located on
the posterior Scapula
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1. Supraspinatus
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2. Infraspinatus
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“Above the scapular spine”
“Below the scapular spine”
3. Teres Minor
4. Teres Major
Common baseball pitcher
injury
Muscles of Head and Trunk
Head
Buccinator
 Orbicularis Oralis
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Orbicularis Oculi
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Allows use to
smile/kiss/whistle
Allows us to blink
Masseter
Allows us to chew
 Wraps around
mandible
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Antagonist #2 (Head Movement)
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Sternocleidomastoid
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Look at the name
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Origin: Sternum
Insertion: Mastoid
process of temporal
bone of cranium
Allows us to flex the
head
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Occipital/Atlas joint
Allows us to rotate
the head
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C1-C2 joint
Antagonist #2 Head Extension
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The antagonist to the
sternocleidomastoid is the
Trapezius (“The Traps”)
 Upper back muscle
 Allows us to extend the
head
 Origin-Occipital bone
 Insertion- T-spine and
clavicle
Antagonist #3 Movement of Trunk
2 muscle groups flex
and extend the trunk
of the body
 Flex the trunk
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1. Rectus Abdominus
“the abs”
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Origin-Sternum (Xiphoid
Process)
Insertion-Pubic
Symphisis
Obliques
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Lateral Flexion of Trunk
Movement of Trunk (Con’t)
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2. Erector Spinae
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Extension of trunk, THE
ANTAGONIST TO THE ABS.
Crucial for proper posture
Serves as antagonist to
abdominal muscles.
Origin: Sacrum
 Insertion: Occipital bone
 Made of 3 parts
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Spinalis
 Iliocostalis
 Longissimus
 Bonus!
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Lower Extremity Muscles
Antagonist #4 (Leg Lifting Muscles)
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1. Iliopsoas
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Made of 2 muscles
On anterior aspect of
body
Flexes the hip joint
(i.e. lifts the entire leg)
Gluteus Maximus
Extends the hip joint
 Located on the “booty”
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Antagonist #5-Knee Lifting Muscles
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2 main muscle groups
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1. The Hamstrings
Located on posterior
aspect of thigh
 Flexes the knee!
 Made up of 3 muscles
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Bicep Femoris
 Semimembranous
 Semitendinous
 Bonus
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Origin: Ischial tuberosity
of ischium
 Insertion: Posterior Tibia
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Antagonist #5 Knee Lifting Muscles
(cont)
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2. Quadriceps
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Located on anterior aspect of
thigh
Extends the knee!
Made of 4 muscles
Rectus Femoris
 Vastus
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Lateral
Medial
Intermedius
 Bonus
Origin: Proximal Femur
 Insertion: Tibial (Shin bone)
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Antagonist to the Hamstrings
Abduction/Adduction of Leg
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Sartorius
Longest muscle in the
body!!
 “Leg Crossing” Muscle
 Responsible for ABDUCTION
of leg (moving leg out)
 Origin: Iliac Crest of Ilium
of Pelvis
 Insertion: Tibia
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Adductor Muscle Group
 Responsible for ADDUCTION
(moving leg in)
Knee Joint
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Quadriceps muscle forms
the Quadriceps Tendon
It extends over the
patella turns into the
patellar tendon
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The patella is formed by
the constant movement of
the leg.
Patellar Tendon inserts at
the Tibial tuberosity
Antagonist #6 Lower Leg Muscles
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Muscles that cover the
tibia and fibula
Allow us to dorsiflex
(point toes toward the
head)
and plantar flex (point
toward the ground)
1. Anterior Tibialis
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On anterior side of tibia
Allows us to dorsiflex
Lower Leg Muscles (Con’t)
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2. Gastrocnemius
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Allows us to plantar
flex (point toes away)
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Origin: Femur
Insertion: Calcaneus
(Heel) via the Achilles
tendon
Muscle Injuries
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Muscle Tears
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A section of muscle
rips
Same as a “Strain”
Muscle Injuries (Con’t)
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Avulsion Fractures
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Tendon injury
Piece of a tendon rips off
the bone due to trauma
Commonly seen in fingers
due to jamming injuries