Musculo skeleton system for Allied health nursing

1. Physiology

3. Muscular system:
It is the system of organs that ensure the
movement of the skeleton.

4. Ø Introduction:
It is the type of tissuse in which cells are
elongated,meant for contraction ,it has got soft
consistency some of the fibers are under
control called voluntary for example skeleton
muscles.
Skeletal mucles are stirated muscles(made of
striped muscles fibers) and known as voluntary
muscles

5. The attachment of skeletal muscles that moves
least is referred as Orgin and the one which
moves most is known as Inseration.

6.  The fleshy part of the mucles is referred is to as
its belly.
 The ends of the muscles which are attached to
the to bones by cord of fibers are called tendon

7.  Flattened muscles are attached by a thin but
strong sheet of fibrous tissue called
Aponeurosis.
 An interdigitation of tendious end of muscles
fibers called raphe.

9.  In the skeletal muscles the muscle fibers are
grouped into bundle called fasciculi,within it
each muscle fiber is surrounded by thin layer
of delicate fibers called Eendomysium, this
layer contains capillaries .
 The Fasciculi are seprated from each other by
connective tissue known as Perimysium which
serves as the route for larger blood vessels
 The whole muscle is covered by layer of
connective tissue called Epimysium.

10. Ø Shape:
The skeletal muscle fibers/cells are cylinderical in
shape,the tapering or rounded at the junction of muscle
and tendon.
Ø length:
Its variable ranging from 1 to 40mm.the length of muscle
fibers depends on the architecture of the muscle being
longest in muscles composed of parallel fibers.
Ø Width:
It varies from 10 to 100 um,depending upon the heaviness
of work its performed.

11.  Muscle with parallel fiber arrangement.

12.  The cytoplasm of the striated muscle cell called
sarcoplasm,it is seen to be occupied mainly by
long, cylinderical, parallel filamentous
elements,1-3 um in diameter,called myofibrils.
 It contains a small Golgi Complex, numerous
Mitochindria , S.E.R, few Ribosomes.
 Longitudinally sectioned skeletal muscle fibers
show cross stirations composed of alternating
dark and light bands.

14. The darker bands are called A-bands.
 The lighter band are called I bands
 Each A band has a central lighter area called H
zone.
 Each I band is bisected by dark transvers line
called Z line.
 The muscle cell which lies between two
successive Z lines is known as a sarcomere,it
is about 2-3 um long and constitutes the basic
contractile unit of muscle fiber.

16.  It is also known as muscle fiber,a basic rod like
unit of muscle .
 It has muscle threads that run parallel throghu
out the muscle .
 These thread like structures known as
microfilaments.two types of microfilaments can
be recognized
 A) thin or actin filament
 B) thick or myosin filament


17.  It represents a specal type of smooth
endoplasmic reticulum that exist in network of
membranous tubules.
 It plays major role in contraction mechanism of
muscle fiber.

18.  All movements in the body are results of the
coordinated action of many muscles.
 A muscle may work in following four ways
I. Prime mover
II. Antagonist
III. Fixator
IV. synergist

19.  A muscle is a prime mover when it is the chief
muscle or member of a chief group of muscles
resposible for the particular movement.
 Example:
 Quardiceps femoris is the prime mover in the
movement of extending the knee.

20.  Any muscle that oppose the action of the prime
mover is an antagonits.
 For example biceps femoris opposes the action
of the Quardiceps Femoris when knee is
extended.

21.  A fixator contracts isometrically means
contarction increases the tone but does not in it
self produces movement to stablizes the origin
of the prime mover so that it can work properly.
 For example muscle of shouder griddle.( it
contracts as fixator to allow deltoid to act on
shoulder joint.

22.  To avoid unwanted movements these muscles
contracts and maintain stability in the joints. For
example flexor an extensor

23.  In skeleltal muscle the capillary supply is very
rich several capillaries having contact with each
muscle fiber

24.  Each skeletal muscle fiber recives at least one
motor nerve ending from the somatic nerve.
 One nerve fiber may innervate a single muscle
fiber or may bramch and may be resposible
forn innervation of many muscle fiber. A motor
nerve fiber and the muscle fiber supplied by it
are collectively referred as motor unit.

25.  Endomycium
 Perimycium
 Epimycium
 Myofibrils
 Myofilaments
 Sarcoplasm