Download Musculature System

Musculature System
So what do muscles do?
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Muscles move cows, snakes, worms and
humans. Muscles move you!
Without muscles you couldn't open your mouth,
speak, shake hands, walk, talk, or move your
food through your digestive system.
There would be no smiling, blinking, breathing.
You couldn't move anything inside or outside
you.
Do I have lots of muscles?
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On average, probably 40% of your body
weight is in muscles.
You have over 630 muscles that move
you.
Muscles can't push. They pull. Muscles
often work in pairs so that they can pull in
different or opposite directions.
How do muscles move?
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The cells that make up muscles contract and then relax
back to original size.
Tiny microscopic fibers in these cells compress by sliding
in past each other like a sliding glass door being opened
and then shut again.
The cells of your muscles use chemical energy from the
food you eat to do this.
Without food, and particular kinds of nutrients, your
muscles wouldn't be able to make the energy to
contract!
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Some muscles are known as "voluntary" -- that is, they
only work when you specifically tell them to.
Do you want to say something? Or swing a bat? Or clap
your hands? These are voluntary movements.
Others, like the muscular contracting of your heart, the
movement of your diaphragm so that you can breathe,
or blinking your eyes are automatic. They're called
involuntary movements.
And how do any of these muscles move? Through
signals from your nerves, and, in some cases, your brain,
as well.
Can you hurt muscles?
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Yes
If you hear someone say that they
"pulled" a muscle, they have, in fact, torn
a muscle in the same way that you can
tear a ligament or break a bone.
Muscle Facts
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You have over 30 facial muscles which
create looks like surprise, happiness,
sadness, and frowning.
Eye muscles are the busiest muscles in the
body. Scientists estimate they may move
more than 100,000 times a day!
The largest muscle in the body is the
gluteus maximus muscle in the buttocks.
3 Types of Muscles
1. CARDIAC MUSCLE:
 The cardiac muscles is the muscle of the brain itself.
 The cardiac muscle is the tissue that makes up the wall
of the heart called the mydocardium. Also like the
skeletal muscles, the cardiac muscle is striated and
contracts through the sliding filament method.
 However it is different from other types of muscles
because it forms branching fibers.
 Unlike the skeletal muscles, the cardiac muscle is
attached together instead of been attach to a bone.
2. SKELETAL MUSCLE:
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The skeletal muscle makes up about 40 % of an adults
body weight.
It has stripe-like markings, or striations.
The skeletal muscles is composed of long muscle fibers.
Each of these muscles fiber is a cell which contains
several nuclei.
The nervous system controls the contraction of the
muscle.
Many of the skeletal muscle contractions are automatic.
However we still can control the action of the skeletal
muscle. And it is because of this reason that the skeletal
muscle is also called voluntary muscle.
3. SMOOTH MUSCLE:
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Much of our internal organs is made up of
smooth muscles.
They are found in the urinary bladder,
gallbladder, arteries, and veins.
Also the digestive tract is made up of smooth
muscle as well.
The smooth muscles are controlled by the
nervous system and hormones. We cannot
consciously control the smooth muscle that is
why they are often called involuntary muscles.
DELTOID
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ORIGIN
Lateral third of clavicle, acromion, spine of scapula to
deltoid tubercle
INSERTION
Middle of lateral surface of humerus (deltoid tuberosity)
 ACTION
Abducts arm, anterior fibers flex and medial rotate,
posterior fibers extend and lateral rotate NERVE
Axillary nerve (C5, 6) (from posterior cord)
TRAPEZIUS
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ORIGIN
Medial third superior nuchal line, ligament nuchae,
spinous processes and supraspinous ligaments to T12
INSERTION
Upper fibers to lateral third of posterior border of
clavicle; lower to medial acromion and superior lip of
spine of scapula to deltoid tubercle
ACTION
laterally rotates, elevates and retracts scapula. If scapula
is fixed, extends and laterally flexes neck
NERVE
Spinal accessory nerve (C1-5)(spinal nerves C3 and C4
for proprioception)
STERNOCLEIDOMASTOID
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ORIGIN
Anterior and superior manubrium and superior medial
third of clavicle
INSERTION
Lateral aspect of mastoid process and anterior half of
superior nuchal line
ACTION
Flexes and laterally rotates cervical spine. Protracts head
when acting together . Extends neck when neck already
partially extended
NERVE
Spinal accessory nerve (lateral roots C1-5)
PECTORALIS MAJOR
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ORIGIN
Clavicular head-medial half clavicle. Sternocostal head-lateral
manubrium and sternum, six upper costal cartilages and external
oblique aponeurosis
INSERTION
Lateral lip of bicipital groove of humerus and anterior lip of deltoid
tuberosity
ACTION
Clavicular head:flexes and adducts arm. Sternal head: adducts and
medially rotates arm . Accessory for inspiration
NERVE
Medial pectoral nerve (from medial cord) and lateral pectoral nerve
(from lateral cord) (C6, 7, 8)
EXTERNAL ABDOMINAL
OBLIQUE
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ORIGIN
Anterior angles of lower eight ribs
INSERTION
Outer anterior half of iliac crest, inguinal lig, public
tubercle and crest, and aponeurosis of anterior rectus
sheath
ACTION
Supports abdominal wall, assists forced expiration, aids
raising intraabdominal pressure and, with muscles of
opposite side, abducts and rotates trunk
NERVE
Anterior primary rami (T7-12)
GLUTEUS MAXIMUS
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ORIGIN
Outer surface of ilium behind posterior gluteal line and
posterior third of iliac crest lumbar fascia, lateral mass of
sacrum, sacrotuberous ligament and coccyx
INSERTION
Deepest quarter into gluteal tuberosity of femur,
remaining three quarters into iliotibial tract (anterior
surface of lateral condyle of tibia)
ACTION
Extends and laterally rotates hip. Maintains knee
extended via iliotibial tract
NERVE
Inferior gluteal nerve (L5, S1,2)
GLUTEUS MEDIUS
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ORIGIN
Outer surface of ilium between posterior and middle
gluteal lines
INSERTION
Posterolateral surface of greater trocanter of femur
ACTION
Abducts and medially rotates hip. Tilts pelvis on walking
NERVE
Superior gluteal nerve (L4,5,S1)
BICEPS FEMORIS
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ORIGIN
Long head: upper inner quadrant of posterior surface of
ischial tuberosity. Short head:middle third of linea
aspera, lateral supracondylar ridge of femur
INSERTION
Styloid process of head of fibula. lateral collateral
ligament and lateral tibial condyle
ACTION
Flexes and laterally rotates knee. Long head extends hip
NERVE
Long head: tibial portion of sciatic nerve. Short head:
common peroneal portion of sciatic nerve (both L5, S1)
PERONEUS LONGUS
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ORIGIN
Upper two thirds of lateral shaft of fibula , head of fibula
and superior tibiofibular joint INSERTION
Plantar aspect of base of 1st metatarsal and medial
cuneiform, passing deep to long plantar ligament
ACTION
Plantar flexes and everts foot. Supports lateral
longitudinal and transverse arches
NERVE
Superficial peroneal nerve (L5,S1)
TIBIALIS ANTERIOR
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ORIGIN
Upper half of lateral shaft of tibia and
interosseous membrane
INSERTION
Inferomedial aspect of medial cuneiform and
base of 1st metatarsal
ACTION
Extends and inverts foot at ankle. Holds up
medial longitudinal arch of foot
NERVE
Deep peroneal nerve (L4, 5)
VASTUS LATERALIS
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ORIGIN
Upper intertrochanteric line, base of greater trochanter,
lateral linea aspera, lateral supracondylar ridge and
lateral intermuscular septum
INSERTION
Lateral quadriceps tendon to patella, via ligamentum
patellae into tubercle of tibia
ACTION
Extends knee
NERVE
Posterior division of femoral nerve (L3,4)
VASTUS MEDIALIS
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ORIGIN
Lower intertrochanteric line, spiral line, medial
linea aspera and medial intermuscular septum
INSERTION
Medial quadriceps tendon to patella and directly
into medial patella, via ligamentum patellae into
tubercle of tibia
ACTION
Extends knee. Stabilizes patella
NERVE
Posterior division of femoral nerve (L3,4)
TRICEPS
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ORIGIN
Long head: infraglenoid tubercle of scapula. lateral head:
upper half posterior humerus (linear origin). medial
head: lies deep on lower half posterior humerus
inferomedial to spiral groove and both intermuscular
septa
INSERTION
Posterior part of upper surface of olecranon process of
ulna and posterior capsule
ACTION
Extends elbow. Long head stabilizes shoulder joint.
medial head retracts capsule of elbow joint on extension
NERVE
Radial nerve (C7, 8) (from posterior cord ), four
branches
LATISSIMUS DORSI
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ORIGIN
Spine T7, spinous processes and supraspinous ligaments
of all lower thoracic, lumbar and sacral vertebrae,
lumbar fascia, posterior third iliac crest, last four ribs
(interdigitating with external oblique abdominis) and
inferior angle of scapula
INSERTION
Floor of bicipital groove of humerus after spiraling
around teres major
ACTION
Extends, adducts and medially rotates arm. Costal
attachment helps with deep inspiration and forced
expiration
NERVE
Thoracodorsal nerve (C6, 7, 8) (from posterior cord)