Muscles anatomy and physiology

1. Mr.Manthan Kapadiya,
Assistant Professor
NCN,Visnagar

2. Objectives
 What is muscle?
 Type of muscle
 Characteristic of muscle
 Classification of muscle
 Nomenclature of muscle

3. TISSUE
 French word “ tissu” – weave or texture.
 A collection of cells together with intercellular
substance, performing similar function.
 4 basic type:
- Epithelial
- Connective
- Muscular
- Nervous

4. Muscle Muscle is a soft tissue.
 Skin – fascia - muscle
 Muscles are primarily designed for movement
 External or internal i.e circulation of blood
 Muscle tissue constitutes 40-50% of total body mass
 Muscle = little mouse in latin
 Types – 1. skeletal muscle
2. smooth muscle
3. cardiac muscle

5. Types of muscle.

6. SKELETAL MUSCLE
 These are most abundant & mostly attached to
skeleton.
 Microscopic : cross striation, multinucleated
cylindrical cells.
 Supplied by somatic nerves, so it is under voluntary
control.
 Respond quickly to stimuli, rapid contraction & so get
fatiguied easily.

7. Skeletal muscle
 parts
1. fleshy (belly)- contractile, vascular
2. fibrous part i.e. tendon- non elastic , less
vascular & resistant to friction, made up of
collagen fibers.
Fibrous part in form of sheet - aponeurosis

8. Tendon

9. Attachments = Origin & insertion
 When a muscle contracts usually one of its ends remains fixed &
the other end moves.
 The fixed end is origin
 Movable end is insertion
 Both can be fleshy
 tendinous
 aponeurotic
 Muscle attachment can be
on the bone, in skin, deep
fascia also.

10. .  Structure of skeletal muscle
 Each muscle is made up of numerous muscle fibers .
 maximum length- 35 cm
 Endomysiym, perimysium, Epimysium

11.  Each muscle fiber is a multinucleated, cross striated
cylindrical cell.

12. Copyright © 2004 Pearson Education, Inc., publishing as Benjamin Cummings
Myofibrils: Site of Contraction
Figure 12-3c-f: ANATOMY SUMMARY: Skeletal Muscle

13. Red Muscles White muscles
 Found in deep muscles &
deeper aspects of
superficial muscles. E.g
soleus muscle
 A dense capillary network
surrounds each muscle
fibre.
 Contraction is slow but
more sustained.
 Found in superficial
muscles e.g biceps brachii
 Poor capillary network
surrounds each fibre.
 Contraction is rapid but
less sustained. Fatigue
develops early .

14. .
 Classification according to direction of muscle fibres
1. parallelmuscle-muscle fibres are parallel to the line of pull . Range of
movement is more but total force of contraction is less.
strap muscle e.g sartorius

15. 2. Pennatemuscle
the fleshy fibres are oblique to
the line of pull. Range of
movement is less but force of
contraction is more.
i. Unipennate – all fibres slope
into one side of tendon at one
margin of muscle.i.e. flexor
pollicis longus
ii. Bipennate – the tendon is
formed in the central axis of
muscle & muscle fibres slope
into the two sides of central
tendon. i.e.dorsal interossei

16. i. Multipennate – a series of
bipennate lie side by side in
one plane. i.e. Deltoid
ii. Circumpennate – muscle is
cylindrical, whithin which a
central tendon appears
i.e. Tibialis anterior

17.  3. spiral muscles –
these muscles are twisted close to their insertion.
i.e. pectoralis major,

18. cruciatemuscles– muscle fibres are arranged in superficial
& deep planes in crossed manner.
 E.g. masseter

19. Nomenclature of muscle:
 A . According to shape-
Shape name of muscle
 Triangular deltoid
 Square quadratus
 Diamond rhomboid
 Round teres
 Slender gracilis
 Straight rectus
 Worm like lumbrical

20. B. According to size –
size name of muscle
Short brevis
Broadest latissimus
Longest longissimus
Other – major, minor, longus

21. .
 C. according to number of heads or bellies –
no. of heads or bellies name of muscle
2 heads biceps
3 heads triceps
4 heads quadriceps
 2 bellies digestric
D . According to depth –
superficial, deep = profundas
externus, internus,

22. E . According to position –
Between bones interosseus
Back dorsi
In abdomen abdominis
Chest pectoralis
F . According to attachment –
stenocleidomastoid
G. according to action –
extensor, flexor, abductor, adductor, supinatur.

23. Latissimus dorsi trepezius
interossii

24. Fig 11-7 a and b

25. Action
 Flexion, extension, adduction, abduction, medial rotation,
lateral rotation, circumduction.
 1. prime movers – are the main muscles that are
responsible for specific movement. E.g flexion at elbow –
brachialis, biceps brachii
 2. antagonists – these muscles have opposite action to
that of prime movers. E.g. triceps is an antagonist to biceps
brachii & brachialis.
However, these muscles smoothens particular movement by
gadually relaxing itself. The speed of relaxation of these
muscles is equal to the speed of contraction of prime
movers.

26.  3 . Fixators – when movements are taking place at
distal end of a bone, the proximal end of a same bone
is kept fixed at proximal joint, so that efficient
movement can take place at distal joint. E.g. shoulder
joint is kept fixed by muscles when movements are
occurring at elbow joint.
 4. synergists – when prime mover is crossing more
than one joint, to get efficient movement at desirable
joint is produced by preventing movement at other
joint by group of muscles called synergists. E.g flexion
of fingers is efficient only when wrist joint is kept fixed
in extended position.

27. Vascular supply
 Neurovascular hilus.
 Arteries divide to form capillaries. Each muscle fiber is
accompanied by a set of parallel capillaries.
 Deoxygenated blood is drained by venules and then into
veins.
Nerve supply – the nerve supplying to a muscle is a mixed
nerve consisting of 60% motor fibers
 40% sensory fibers- α efferent
 -γ efferent
 sensory supply carry sense of pain, joint position
 Lymphatic channel accompany the vessels.

28. Neurovascular supply

29. Short note - muscle
 e.g. deltoid or popliteus etc
 introduction + any peculiarity
 Origin
 Insertion
 Nerve supply – particular name
 Action
 Applied anatomy / clinical notes

30. Muscle spindle Are concerned with maintainance of muscle tone.
 they lie myotendinous junction parallel to muscle fibres.
 Act as stretch receptor.
 Important : even in relaxed posture muscle remains in
some tension.
 Play a part in conscious appreciation of the position &
movement of the joint.
 Consist of intrafusal fibers.
 Nuclear bag fibers
 Nuclear chain fibers

31. Muscle spindle

32. Lubricating mechanisms
 1 . Synovial sheath – the tendons while passing under
the fibrous bands like retinaculum, are surrounded by
synovial sheath.
 Consist of two members.
 Contain capillary film of synovial fluid

33. . synovial bursa
 a bursa is a closed sac filled with
lubricating fluid, resembles size and
shape of a coin.
 Lies between tendon and bone,
tendon and ligament
 To diminish friction and
allow free movement.

34. Applied anatomy
 1. paralysis – when a muscle is unable to contract, it is
called paralysis.
 Hemiplegia – when muscles of one side of body are
paralysed
 Paraplegia – both lower limbs
 Quadriplegia
 2. muscle spasm- is a sudden, violent, involuntary, muscle
contraction.
E.g. tetany
 3. regeneration – skeletal muscle is capable to regenerat in
limiting range. Hypertrophy of a muscle seen after an
exercise is not due to increse in number of muscle fibers
but increse in number of myofibrils.
 4. myositis, tendinitis, bursitis - immflammtion

35. Smooth muscle
 These muscles often encircle/surround the viscera
 Each muscle fibre is an elongated, spindle shaped
nucleus with single central nucleus
 Do not shows cross striation

36.  Supplied by autonomic nerves, not under voluntry
control
 Responce slowly to stimuli,being capable to sustain
contraction so do not fatigue easily
 Provide motor power for regulating the internal
environment related to digestion, circulation,
secretion & excretion.

37. CARDIAC MUSCLE
 It form myocardium of heart
 Each muscle fibre having single nucleus which is
centrally placed, anastomosis with neighbouring fibres
at intercalated disc
 Cross striations less prominent then skeletal muscle.

38.  Automatic & rhythmic contraction
 Intermediate, being stiated & same time involuntary
 Main charateristic feature of cardiac muscle is
intercalated disc, which is a junction between adjoing
cardiac myosite.

39. Comparision between three muscle
characteristic Skeletal muscles Cardiac muscles Smooth muscle1.
1. Location Usually attached to
the bones of the
skeleton
In Heart Wall of hollow
viscera, blood
vessels, arrector
pili muscle.
2. Fibres
Shape Unbranched
cylindrical
Branched,
cylindrical
Spindle shaped
Nucleus Multinucleated,
placed at
periphery,
Single nucleus,
Centrally placed
Single nucleus,
Centrally placed
Striation Prominent
transverce
striation (light &
dark band)
Faint transverse
striation
Not present
3. Nervous control By somatic nerves By autonomic
nerves
By autonomic
nerves
4. Autorhythmicity No Yes yes

41. Question 1
 Which one is voluntatry muscle
a. Skeletal muscles
b. Cardiac muscles
c. Smooth muscle

42. Question 2
Identify the given
picture
a. Smooth muscle
b. Cardiac muscle
c. Skeletal muscle
d. Involuntary
muscle

43. Question 3
Identify the given
picture
a. Smooth
muscle
b. Cardiac muscle
c. Skeletal
muscle
d. Voluntary
muscle

44. Question 4
Identify the given
picture
a. Smooth muscle
b. Cardiac muscle
c. Skeletal muscle
d. Striated muscle

45. Question 5
 Which muscle has characteristic of intercalated disc.
a. Smooth muscle
b. Cardiac muscle
c. Skeletal muscle

46. Thank you