Lecture on muscular system

1. The Anatomical and
physiological particularities of
bone and muscular systems &
its clinical importance. The Teeth
and teeth formula.

2. The First kernel of the large bone ossification
appears in a 7-8 weeks aged embryo within its
in uteri development. Consequently, at this
time it is possible to consider that bones of
the child skeleton arise.

3. After birth the size of skeleton increases very
intensively according the mass and length growth
of baby body. In this period at list until to 3 years
of age the child skeleton can not be estimated as
stable, firm structure. So called the bone
rebuilding processes are running very intensively.
Alongside with bones growing lengthwise and
width, big importance has a realignment of the
direction of bone beems under gravitation stimulus
influence changing in its direction within childhood.

4. The fetus and newborn have a sponge like
bone masses (A). After age of 3-4 years
children have the lamellar built big bones and
their bone beems are orientated strictly
against earth attraction (gravity, Б). For the
first year of the life about 70% bone tissues
are reutilized and rebuilt.

5. The regeneration and healing processes in
child bones occur in contrast with adult
much sooner. Because of sponge like
construction and special in contrast with
adults chemical composition (pro rata more
significant contents of water and organic
material vs. mineral materials) the children
bones are soft and flexible. That is way
children are less predisposed to fractures
by comparison with adults.

6. Periosteal tissues (a bone
cover) provide supplemental
trofic function. By comparison
with adult persons in children
it makes the massive
stretchy formation over the
bones and can play an
additional protective role to
resist fractures. Even if the
child brakes a bone there
can be found only so called
“subperiosteum fracture” (the
fracture without bone parts
offset). The other name of this
fracture is toddler`s variant
on type of "green branch".

7. Toddler's fracture.
Anterior-posterior
radiograph of tibia.
Spiral fracture is
presented.

8. 3 parameters associated with bone tissue
development and biochemicaly same teeth matrix
should participate in biological child age
estimationon.
The Biological age can be evaluated on:
• child growth (body length or height),
• terms of bone ossification (ossification centers
appearing),
• terms of dentition (appearing of constant teeth).

9. The bone, growth, teeth and passport age
coincidence is indicative for the normal
biological development in a child. If the age
of psychic development also corresponds to
the biological and passport ages you should
consider the child as a harmoniously
developed one. In opposite event the
conclusion about decelerated, accelerated or
disproportional child development has to be
done.

10. The skeletonexamination

11. Estimating the bone system the next
clinical approaches are useful:
• Complaints
• Additional questioning (case history)
• Objective methods:
visual inspection
palpation
bone percussion sometimes
• Instrumental (mainly X-Ray) investigations.

12. Visual inspection & palpation
• The Objective investigation of the skeleton
is recommended to conduct from the top
to bottom (from the head vertex to the
feet).

13. The skull

14. In newborns and early infants the skull has more developed
brain part in contrast with a face skeleton. The brain skull
consists from paired or dabbled bones including frontal
bones and unpaired occipital bone. The opened and formed
by elastic membranes sutures separate one scull bone from
another. This sutures are closing within the infancy period
but lock up completely only in school age. This process is
identified as a synostosis.
There are a fontanels in points of bones joining on. Anterior
fontanel is situated between frontal and temporal bones.
Its normal size at birth is 2-3 sm referring to a measurement
perpendicular to the bone edges. Its synostosis occurs in
age between 4 to 18 mo. Posterior fontanel is found between
temporal and occipital bones. It is locked in 75% of full term
newborns. In rest of the children the posterior fontanel
closes by the end of the first month of life.

15. The chest

16. In small children the thorax has rounded
form and starts to be flat in anterior-posterior
axis in school age. In small children the
breathing mostly is provided by diaphragm.
The ribs for the first year of life are located
horizontally as they were in position of the
maximum inspiration in adults. When the
child begins to walk the diaphragm is
lowered gradually and ribs take a tilt position.

17. The spine.

18. Spinal curves
• In newborns the spine is direct with a small
protuberance backwards in the area of rump. There
are not cervical, thorax or pelvic physiological spine
deviations in anterior-posterior direction. They will be
very useful for amortization of the spinal column when
the child walks, jumps.
• After the child lies in prone position and begins to
raise slightly the head upwards the cervical lordosis
(onwards spinal arc) is forming. When the child starts
to sit down the lumbar lordosis and to stand up the
chest kyphosis will appear. The cases of the
exaggerated lordosis and kyphosis (backwards spinal
arc especially in thorax) are defined as hyperlordosis
and hyperkiphosis and are to be treated.

19. The teeth are a skin appurtenance because
they are derived from the embrio ectoderma.
But on their biochemistries and physiologies
the teeth and especially dentin are very
closed to bone tissue. That is way in pediatric
practice traditionally the teeth condition is
used as marker of the bone tissue welfare.

20. The appearing of baby teeth (or primary
deciduous teeth) is called as a dentition. The
dentition or teething begins in children aged
6-7 mo. The process can de written by
formula where the teeth are marked with five
first letters of Latin alphabet. A one year old
baby as a rule has all 8 primary incisors.
This deciduous dentition (teeth formula) is:
BA|AB
BA|AB

21. A 12 -15 mo old child as a rule has the first or
anterior premolar teeth( D):
D BA|AB D
D BA|AB D

22. A 18 - 20 mo old child has the fangs (C)
teethe:
DCBA|ABCD
DCBA|ABCD
A 22-24mo - second or posterior premolar
teeth (E). So a 2 years old child as a rule has a
full complement of baby teeth. They are 20:
EDCBA|ABCDE
EDCBA|ABCDE
Empirical formula for infantil teething is n = m – 4,
where m – mo of age till 24, n – deciduous teeth
quantity

23. Unlike infantile teeth a succedaneous
(secondary) teeth have a bone alveolus and
developed roots. The order of succedaneous
(secondary) teeth dentition (the formula is
marking by Arabic numerals only) follows
the primary baby teeth changing. The first
molar (6) tooth appears at age of 5-7 years.
This moment the teeth formula consists from
primary and secondary teeth:
6EDCBA|ABCDE6
6EDCBA|ABCDE6

24. The incisors are changing at age 7-9 years:
6EDC21|12CDE6
6EDC21|12CDE6
At age of 10-12 years in children the intensive
secondary teething occurs. The
succedaneous fangs (3) and premolars (4
and 5) change deciduous ones. The second
molars (7) apeare. A little bit later the third
molars (8) appear. This teeth are called “a
teeth of wisdom". .

25. What is the “difficult" teething?
• Pain, itching, hypersalivation.
• Head cold.
• Fever.
• Diarrhea.
• Always a physician has to pay attention to
complicated dentition which a parents as a rule
involve with term "difficult but harmless
teething”.

26. The features of muscles in
children

27. Some features of muscles
• The hystomorfological studies of muscular tissues in young children
show the short and thick myocytes containing big amount of cell
nuclei, abundance of interstitium and blood vessels.
• The children skeleton muscles comparatively with such adults contain
less myosin and actine contractive proteins and more water. As a
result the children muscles are very stretchable and are not prone to
ruptures.
• The strength of muscular contractions is lesser then in adults.
• It is considered that intensive blood flow in children muscles
promote quick elimination of acidity forming during muscular load.
This fact explains the high physiological muscular activity in children
which can feel the true muscular joy moving. In any event it is
prohibited to limit children in their motor activity.
• Common muscular mass begins to increase only in teens - from 22 -
25% from body weight in pre-pubertal children up to 45% in male-
teenagers aged 15 years. The muscular mass increasing occurs by
account of each myocyte size increasing. The represented facts
undoubtedly witness that so called "body building" and other athletics
are for children younger 13 meaningless and even harmful.

28. The skeleton muscles clinical
investigation
• The complaints most often concern such subjective
sensations of pain in limbs and motion restriction.
This complaints commonly are related with
consequences of traumas which happen in children
very often.
• The spontaneous pain is characteristic for myalgia.
For children it is very typical the muscular pains
related with fever. The mechanism of their origin is
not clear yet.
• The muscle groups clinical survey usually combines
with their palpations. During this procedure it is
necessary to reveal the muscular atrophies,
hypertrophies, contracturas and tenderness.

29. Thanks for your attention!