Congential Growth Diseases Medullary Injuries Mobility Spina Bifida
What is a Congenital Defect?
It includes the functional and structural anomalies of the embryo or fetus derived
from factors present before the birth. It is a wide definition where genetic defects
(genic or chromosomic) environmental or unknown are implicit, the same as all
alteration that is not apparent in the newly born and it is only manifested lately.
This definition includes the dysmorphic defects, independently of its origin and
condition (Malformations, disruptions, dysplasia, syndromes) as well as the mental
and sensorial deficiencies: (Pan-American Organization of the Health - 1984).
Types:
The malformations can be of different type and cause.They are part of what is
known as Manifestations of Alterations in a Newly Born that are divided in 4 groups.
Congenital Malformations: these imply to incorporate genetic material with alteration
known at the moment of birth. There are also malformations that can appear, many
years after the child was born, as degenerative and cerebral neuromuscular diseases.
This happens because the alteration is incorporated in the genetic material.
Deformations: (for example deformed skull) they are caused by mechanical failures
in which the genetic material does not takes part. Many deformations are usually
corrected and others require surgery.
Disrruptions (interruptions): it is characteristic because the genetic information
is correct and the development of the fetus begins normally until some interference
in the process occurs. For example a blood vessel is blocked obstructing the flow
of blood toward the end of the extremity being this prone to atrophy
Displasia: It is altered cellular information. As the liver displasia that comes
with faulty cells.
Frequency:
Any pregnant woman, for the single fact of being, has a risk of 2 to 3% of having
a child with some malformation, this is, of each 100 pregnancies 2 or 3 babies
could be born with some evident defect at birth. This malformation can go from
something irrelevant up to a a cardiopathy.
Most of the malformations are present in healthy families without antecedent,
even though they are of a hereditary character because there exists a mutation
rate.
Causes:
It is known that congenital malformations have a multifactor origin and that they
are developed in the first months of gestation. In their origin factors having
to do with the health of the parents, especially of the mother, being very important
for example the mother's age, the infections during the pregnancy, the nutrition,
the consanguinity among the parents, genetic factors, and environmental factors,
such as the toxics ingenta during pregnancy, taking a preponderant place, tobacco,
drugs and alcohol.
The consumption of alcohol during pregnancy, even in minimum quantities, is an
important risk factor that can produce physical and mental deficiencies in the
embryos. The most habitual malformations are the cardiovascular ones, followed
by the osteomuscular and those that affect the genitourinary system and the Central
Nervous System.
Growth Diseases
What it is growth?
The growth is a dynamic phenomenon through which the individual reaches a certain
size, increases progressive and proportionally in weight and attains a characteristic
psychomotor and hormonal development of the mature age according to the corresponding
sex. All of us have more or less the same size when we are born, but the final
size of some of us will be within a normal size and others within a low mean size.
A child when being born measures around 50,9 cm and grows about 25,4 cm during
the first year of age. At two years old the child will have reached 89 cm in height
. From 2 until 12 years old, the child grows to a speed from 5 to 6,35 cm a year.
The pubertal push begins around 11 years in the girls and at 13 in the boys. This
pubertal growth lasts two years and is accompanied by the sexual development.
This development ceases between 16 and 18 years olod when the growth finishes
in the bones fusion.
The height of an adult is determined by multiple factors, including the parents'
height, the age at which puberty begins and the acceleration of the growth speed.
Pattern of normal growth variants?
There are growth variants, some of them are pathological:
Quick Maduration: Some children are higher of the media of those of their
chronological age. The size is accompanied by an acceleration of the bony maturation
and of the pubertal development. The growth endsat an early age, the adult size
is normal.
Low or constitutional family size: It is the pattern of normal growth variant.
It deals with children that have a development pattern characterized by the low
size during childhood, normal or lightly retarded maturation rhythms that conclude
their period of growth at the habitual age and they reach a stature related with
that of the parents.The diagnosis is generally easy starting from the family history,
growth curves and bony age assessment , which is normal for the chronological
age.
Constitutional Slowing of growth and puberty: It is a physiologic situation
that transitorily simulates a definitive growth alteration. Delay exists in length,
bone maturation, and sexual development.
They are children that grow slowly during the whole childhood and they are below
the media corresponding to their chronological age, the stature growth corresponds
to the bony age that is usually retarded two or three years. When arriving to
the puberty the growth acceleration characteristic of this stage does not take
place, neither the sexual maturation begins, nor the skeletal development advances.
These pubertal changes do not occur up to between 16 and 19 years.Types of diseases
and disorders causing low size.
Bony Displasias: The malformation in the development of the cartilage and
the bone produces another form of low size. Children with a skeletal displasia,
are small and their body is disproportioned, the intelligence is normal. Some
bony displasias are inherited, others are not, although the causes of most of
the displasias are ignored.
Slowing Intra-uterine Growth: Prematurely born children are very small,
nevertheless their size is normal given their gestation age (period of time in
the uterus). But some children are smaller and they weigh less than what they
should when born, they did not reach the lenght and weight according to their
period of gestation. This slow-growth type in pregnancy, is called "slowing
intra-uterine growth".
Medullary Injuries
What it is?
Any damage to the spinal cord is a very complex lesion. Each lesion is different
and it can affect the body in different ways.
Normal Spinal marrow:
The nerves are structures similar to a cord made up of many nervous fibres, these
send messages between the brain and the different parts of the body, these messages
can be related to movement, or messages of sensation or tact from the body towards
the brain, as heat, cold, pain,. Therefore, these nervous fibres constitute the
body's system of communication and the spinal marrow is the path the messages
use, and it is made up of spinal nervous fibres.
Since the spinal marrow is a vital part of our nervous system, it is surrounded
and protected by bones called vertebrae, placed one upon the other one, known
as spine or spinal, principal support of the body.
The spinal marrow extends from the brain base, down to half of the back. The sheaf
of nervous fibres which makes up the spinal marrow itself are the "superior
motor neurons". The spinal nerves ramify from the spinal marrow upwards and
downwards the neck and the back, these nerves, the "inferior motor neurons",
come from between each vertebra and reach to all parts of the body.
The spine or spinal, is divided in four parts or sections: Cervical (made up of
seven cervical vertebrae), Number (it includes the chest area and it has twelve
dorsal vertebrae), Lumbar (it is the low back section and is made up of five lumbar
vertebrae) and the Sacrum (it has five sacrum vertebrae, fused together in a single
bone).
Spinal marrow after a lesion:
A lesion of the spinal marrow may occur due to an accident or to a damage as a
result of an illness in the spine or the spinal marrow.
After a lesion in the marrow, all the nerves above the lesion level go on working
in a normal way. Below the lesion level, the nerves of the spinal marrow cannot
send messages between the brain and the different parts of the body, as they made
it before the lesion.
By means of X-rays is possible to determine in what part of the vertebrae had
been damaged. Each lesion of the spinal marrow is different, a lesion in a person
is described in its level and its type.
According to the type, it can be classified as partial or total, this depends
on the amount and type of messages that can be sent between the brain and the
different parts of the body; that is to say, depends on how some nerves have been
damaged and not others.
Some people with partial lesion may have sensation but little movement. Others,
may have some movement but very little sensation. Spinal partial lesions vary
from one person to other because each person's spinal cord nervous fibres are
damaged differently.
The lesion level is located at the lowest point, below the spinal cord, in which
there is a sensation decrease or absence (sensitive level) and also of the movement
(motor level).
The higher it is the spinal cord lesion, or nearer the brain it is, the higher
the function loss (sensation and movement).
Changes that occur after the Initial Lesion:
After the initial lesion the marrow sometimes becomes inflamed. When the inflammation
yields, the nerves start to function again, although there is no test to determine
how many nerves can do it. (start to function again. )
Some people experience involuntary movements (tremors or nervous movements) called
spasms. Spasms are not a recovery sign, they occur when a mistaken message of
a nerve makes a muscle move and therefore people cannot control the movement.
Besides movement and sensation, movement in the spinal marrow affects other body
functions. The lungs, intestines and bladder do not function with total normality,
just as it had occured before the lesion.
Mobility impairments range in severity from limitations on stamina to paralysis.
Some mobility impairments are caused by conditions present at birth while others
are the result of illness or physical injury. Students often use a wheelchair
or other assistance device. A physical disability should not imply that a student
has other health problems or difficulty with intellectual functioning. Dependency
and helplessness are not characteristics of physical disabilities. A wheelchair
is a personal-assistance device rather than something one is confined to. It is
also a part of a students personal space; do not lean on or touch the chair,
and do not push the chair unless asked.
Physical access to a class is the first barrier a student with a mobility impairment
may face. This includes not only access to the building or classroom; but also
an unshoveled sidewalk, new construction along a route, or mechanical problems
with a wheelchair can easily cause the student to be late.
Possible reasonable accommodations applicable for someone with a mobility disability:
· Allow the use of tape recorders for taping lectures and discussions
· Relocate the classroom to a more accessible location. A student with
a mobility impairment, oftentimes, must arrange a specific class schedule. The
scheduling of certain inaccessible classrooms is sometimes due to a lack of sections
offered and/or the time and day that the class is offered
· The faculty member should use the classroom entrance(s) accessible to
a student with a disability. Sometimes students who use a wheelchair must sit
in the back of large lecture rooms because of interior steps. This seating arrangement
limits the student's opportunity for talking informally with the professor after
class. The professor should make a special effort to speak to the student on occasion
to ascertain that he/she is progressing in the class
· Advance notice for field trips should be given in order for adequate
transportation to be arranged and plans for wheelchair accessibility to be made
· Administer a test with a time extension. The student and the instructor
should be able to agree on an appropriate amount of time
· Allow the student to tape record answers
· Give regular test allowing the student to use a writer. The writer may
be the instructor, a graduate assistant, , or a writer selected by the student.
The test should be given in a quiet area away from the other students taking the
test. This type of testing usually requires extra time to complete
· Allow the student to take home the test and complete it. This is the
least desirable testing accommodation
· Check the final exam schedule to determine if the test is offered in
an accessible location
What it is?
The Spina Bifida is a congenital malformation of the neural tube, its features
are that one or several of the posterior vertebral arches have not fused correctly
during the gestation period, so that the spinal cord remains in that place without
bone protection. The defect originates precociously in the first month of gestation.
There are two types of Spina Bifida:
Hidden Spina Bifida: The less serious type. Usually discovered in X-rays exams,
since it does not show neurological or skeletomuscular dysfunctions.
Cystic Spina Bifida: The most serious type, the lesion usually appears as a swelling,
in cystic form, in affected area of the back. Several types are distinguished:
Meningocele and lipomeningocele. A meningea bursa which contains cephalorachidean
liquid is generated. It means less serious sequels, not only in locomotives functions
but also urinary.
Myielomeningocele: Besides cephalorachidean liquid, in this case the swelling
contains spinal cord and rachidean roots. It is the most serious affection and
it originates sequels at the locomotive, urinal and digestive level. The nearer
the head is to the lesion, the more serious are their effects.
Causes:
Causes not exactly known, although researchs suggest that most of the cases it
is due to the existence of a pholate deficit in the mother's organism in the previous
or immediately later pregnancy periods.
In spite of the fact that it is not a hereditary malformation, it could be thought
of genetic factors that would predispose or would suppose a higger risk of spina
bifida. Lastly, there would be a series of factors that could also determine the
development of this malformation which leads to a descrease in the pholate reserves,
or their fixation: antiepileptic drugs, products for psoriasis or acne, treatment
with sexual hormones, diabetes, alcohol or drugs consumption, low diet in pholates
or oligoelements.
Sequels:
These will depend on at the level of the spine where the lesion is located, repercussions
are greater at higher levels.
Affected people suffer from sensibility loss below the lesion level and muscular
weakness that goes from mild cases to complete paralysis. They also suffer from
orthopedic alterations, like hip luxation, feet malformations or backbone deviations.
Urologic complications as a result of alterations in muscular nervation in the
bladder which cause urinal infections, reflux, and sphincter incontinence. In
turn, 70% of those affected presents hydrocephalia, product of the accumulation
of cephalorachidean liquid in the cranial cavity, nevertheless with a precocious
treatment, most of the hydrocephalic children have possibilities of a normal intellectual
development.
Diagnosis:
Spina Bífida can be detected precociously during pregnancy. It is possible
to establish a precocious diagnosis by means of the determination of the levels
of a protein called alfafetoprotein in the mother's blood. These studies should
be carried out before the 20th week of gestation.Prevention:
Although a specific treatment does not exist, many of these congenital malformaciones
of the neural tube could be avoided by means of the pharmacological contribution
of pholates before pregnancy takes place (of 3 to 6 months) and during the first
three months of the same one, since it is the moment in that he/she is formed
the neural tube. Preventing this malformation through the pholic acid (Multivitamins)
has diminished the appearance of this defect.
|