The adult human skeleton consists of 206 bones. The bones along
with approximately 700 skeletal muscles, account for 50% of our body weight.
Bones provide protection and support. When two or more bones join
together, a joint or articulation is formed. Through several types of joints,
they help in movements.
Fractures
Fracture is defined as a break or crack in the bone. Trauma or injury
to the bones of human body is getting increased with the development of
industry and transportation. Trauma is the biggest killer and maimer of human
beings all over the world. Hippocrates in the 14th century B.C. described
the treatment of fractures and injuries to limbs. In India, the treatment of
fractures to limbs is still carried out by traditional bonesetters. Modern
methods of treatments are available. They are more scientific and
appropriate.
Types of fractures :
1.Green stick fracture : – This fracture occurs in the young bones of
children. This fracture break is incomplete leaving one side of the cortex
intact.
2. Closed fracture :- A closed fracture is the one where the haematoma
(blood clot)does not communicate with the outside.
3. Open fracture (Compound fracture ) :- In this type, the fracture
haematoma communicates with the outside through an open wound. It is a
serious injury through which infectious germs may enter into the body.
4. Pathological fracture :-This type of fracture occurs, due to pathological
lesions after a trivial violence in a weak bone. It may be due to
hyperparathyroidism.
5. Stress fracture :- It is a fracture occurring at a site in the bone, due to
repeated minor stresses over a long period of time.
6. Birth fracture :- It is a fracture occuring in the newborn babies due to
injury during delivery.
An acute hepatitis may happen due to variety of causes. Its
manifestation is inflammation of the liver. Such inflammation may happen
due to viral infection. Non-infectious hepatitis can happen due to excessive
alcohol consumption. In early stage, the symptoms are not conspicuous. The
symptoms include fatigue, poor appetitie, nausea, vomiting, fever and
discomfort in upper right side of the abdomen. There is no specific
treatment. People are usually advised to take rest, and avoiding drinking of
alcohol.
These are the stones of various sizes and content that form in the gall
bladder. The stone formation occurs in about 1/10 people, over 40 years of
age. The Gall stones are formed by bile. Bile is made up of cholesterol,
pigments and several salts.
Any alteration in the composition of the bile can cause the formation of stones. The stones are mostly formed of cholesterol. There is no obvious reason for such a formation. However, obesity is a risk factor.
High fat diet can also cause stone formation. In severe, complicated situations it may block the bile duct and cause jaundice.
It is the inflammation of the appendix, leading to severe abdominal
pain. Appendix is a small blind ended tube found at the beginning of the
large intestine. This disorder is very common among adolescents. It is more
common in developed countries where diet contains less fibre food. The
inflammation causes blockage. The closed end of the appendix beyond the
blockage then becomes infected by bacteria.
The early symptoms includes sudden pain in the upper abdomen,
nausea with or without vomitting. It may also cause mild fever. If a
treatment is delayed the appendix may rupture and result in infection in the
abdomen. The serious infection is called as peritonitis. The treatment
involves the removal of appendix by surgery.
Hernia is commonly called “ruptures”. This occurs at a weaker
region in the abdominal muscle.
Due to increased pressure in the abdomen, the muscles become streched at the weak point, the pressure may be due to lifting heavy weights, continuously.
Due to hernia, a visible bulge can develop. It will contain fatty tissues or part of the intestine. Abdominal hernias are common in men having heavy manual job.
In hernia, a section of intestine may become twisted and get traped
inside the bulge.
The blood supply may be cut off. This is known as strangulated hernia. If it causes severe pain immediate surgery is needed. Hernia can occur in other areas of the body.
Types of Hernia
1. Inguinial Hernia – a portion of the intestine pushes through inguinial
canal. This region is the weak spot.
2. Femoral Hernia – It occurs in the part of the groin where the femoral
vein and artery pass from the lower abdomen to the thigh, women who are
over weight (or) who have several pregnancies may be affected.
3. Umbilical Hernia – It develops in babies, behind the navel due to
weakness in the abdominal wall.
Hernia repair – For hernia often a simple surgery is needed. It is done by
using local or general anaesthesia.
Peptic ulcer is refers to an eroded area of the tissue lining in the stomach or
duodenum. The lining of stomach or duodenum are protected from the
effects of HCl by a layer of mucous. If the mucous layer is damaged, the
acid may cause inflammation and erosion of the lining. It is known as peptic
ulcer. Ulcer is of two types namely, duodenal and gastric. Of the two,
duodenal ulcer is more common. It occurs in people in the age group of
25 – 45 years. Gastric ulcer is more common in persons above the age of 50
years. Peptic ulcer is a very common gastric ailment.
Causes for Peptic ulcer
The ulcer is mostly due to infections by a bacterium called
Helicobacter pylori. It may also be caused due to uncontrolled usage of
aspirin or certain anti inflammatory drugs such as Ibuprofen. Ulcer may also
be caused due to smoking, alcohol, coffiene and psychological stress. In
severe peptic ulcer, upper digestive tract endoscopy is done to assess the
extent of damage. A bleeding or perforated ulcer requires hospitalization.
Common treatment of ulcer is aimed at healing the ulcer and preventing its
recurrence. Life style changes such as giving up smoking and alcohol may
be required. Anxiety, stress, strain and worrying should be avoided.
Root Canal Treatment is a modern dental procedure to save a tooth in which the pulp (the living tissue within a tooth) has died or become untreatably diseased, usually as a result of extensive dental caries.
Steps involved in Root Canal Treatment
(1) A hole is drilled into the crown to remove all material from the pulp
chamber. The root canals are then cleaned with fine-tipped instruments. The
procedure is usually monitored by X-rays.
(2) The cavity is washed out, and antibiotic paste and a temporary filling
are packed into it. Some days later, the filling is removed and the canals are
checked for sterlity.
(3) When no infection can be detected, the cavity is filled with a sealing
paste and/or tapering solid “point” made of gutta – percha resin mixed with
zinc and bismuth oxides. The mouth of cavity is then sealed with cement.
Tooth decay is the gradual erosion of enamel (the protective covering
of the tooth) and dentine (the substance below the enamel). Plaque
formation is the main cause of tooth decay. The most common sites of initial
decay are areas where plaque easily becomes trapped, such as the grinding
surfaces of the back teeth (which have minute grooves in them), the lateral
(side) edges of adjacent teeth, and near the gum line. Plaque consists of food
remains, salivary mucus by-products, and the bacteria that live in the mouth.
The bacteria feed mainly on the fermentable carbohydrates (simple sugars
and starches) in food, and in breaking them down, create an acid that
gradually destroys enamel, forming a cavity. If the process is not checked,
the dentine gets eroded. The cavity gets enlarged enabling the bacteria to
invade the pulp at the centre of the tooth and causes infection.
Symptoms of Dental Caries (Tooth decay):
Early decay does not usually cause any symptoms. The chief symptom
of advanced decay is tooth ache, which may be aggravated by eating very
sweet, hot or cold food. Decay may also cause bad breath.
Treatment for Dental Caries (Tooth decay) :
Treatment consists of the drilling away the area of decay and filling the
cavity with either dental amalgam (a mercury alloy) or cement (a composite
resin that matches the colour of the tooth). In cases of advanced decay, it
may be necessary to remove the infected pulp (the central, living part of a
tooth) and replace it with a filling or to extract the tooth.
The digestive system includes the gastro-intestinal tract (mouth to
anus) and the glandular organs. This system serves to transfer organic
molecules, salts and water from the external environment to the body’s
internal environment. Most of the food taken into the mouth are large
particles containing macromolecules such as polysaccharides and proteins.
As such they cannot be absorbed by the intestinal wall. They must be
dissolved and broken down into much smaller molecules. This process is
named as digestion. Digestion is accomplished by substances called enzymes
produced from the digestive glands. The enzymes are biocatalysts in the food
breakdown process.
The process of digestion
Mouth :-
In the mouth, digestion starts with chewing. It breaks up large
pieces of food into smaller particles that can be swallowed without choking.
It is accomplished by teeth, tongue, jaws and saliva.
Chewing is controlled by the somatic nerves to the skeletal muscles
of the mouth and jaw. Rhythmic chewing motions are reflexly activated by
the pressure of food against the gums, hard palate at the roof of the mouth
and tongue.
Saliva :- (digestive system)
The saliva is secreted by three pairs of exocrine glands, namely :
the parotid, the submandibular and the sublingual. The daily secretion of saliva
ranges from 1000 to 1500ml. It contains the organic substances amylase
and mucin. The salivary amylase or ptyalin can act on starch. It converts
cooked starch into the disaccharide, maltose. Mucin is a glycoprotein. It
helps in the lubrication of food. The lubricated, swallowable form of food is
called the bolus. The salivary secretion is controlled by reflex activities.
Swallowing :- (digestive system)
It is a complex reflex activity. It is controlled by the
swallowing center in the medulla oblongata. During swallowing the soft
palate is elevated, the larynx gets raised. The tongue forces the food back
into the pharynx, the epiglottis closes the glottis and the food slowly passes
into the oesophagus.
The oesophageal phase begins with relaxation of the upper
oesophageal sphincter. In the oesophagus the food is moved towards the
stomach by a progressive wave of muscle contractions that proceed
downward to the stomach. Such waves of contraction in the muscle layer
surrounding a tube is known as peristaltic waves. In the oesophagus one
peristaltic wave takes about 9 seconds to reach the stomach. Due to
peristaltic waves, swallowing can occur even while a person is upside down.
The stomach (digestive system)
It is a wide chamber, located below the diaphragm. The size and
shape of the stomach depends on the food inside it. The stomach volume
during feeding may increase upto 1.5 lit. Stomach’s primary contractile
action will produce peristaltic waves. Each wave begins in the body of the
stomach and proceeds towards the pyloric region. The initial wave
influences the muscles to close the pyloric sphincter, a ring of smooth muscles
between the stomach and the duodenum.
The inner wall of the stomach is lined with gastric glands. There are
nearly 40 million glands engaged in producing gastric juice. The chief cells of
the lining of stomach secrete enzymes and the parietal cells (Oxyntic cells)
produce HCl to create acidic medium for enzymes.
The enzymes of the stomach are the pepsin and rennin. Pepsin is
secreted in an inactive precursor form known as pepsinogen. The activity
due to HCl converts pepsinogen into pepsin. Pepsin hydrolyses the proteins
into short polypeptide chains and peptones. It is most effective in an acidic
environment.
Proteins
pepsin
polypeptides + peptones
Rennin acts on soluble milk protein caesinogen and converts it into
insoluble casein. In the presence of calcium ions casein is precipitated as
insoluble calcium-casein compound (curds).
Repeated peristaltic waves in the stomach help to soften the food.
The frequency of contraction is determined by the basic electrical rhythm
and remains essentially constant. It is also aided by neural and hormonal
influences. The food leaves the stomach in the form of chyme and enters the
upper small intestine at periodic intervals.
The small intestine :- (digestive system)
It is about 5-7 metres long. It is divided into three
segments namely the initial short segment the duodenum, the jejunum and
the longest segment the ileum.
The food is propelled down into the duodenum due to peristaltic
action of stomach wall. The pyloric sphincter located at the junction of
stomach and duodenum regulates movement of chyme.
The food in the small intestine is mixed with three juices namely bile
juice, pancreatic juice and intestinal juice.
Bile juice :-
It is a brownish green, alkaline secretion of the liver. It is stored
in the gall bladder and poured into the duodenum via the bile duct. The bile
contains water, mucus, inorganic salts, cholesterol and bile salts. The bile
salts emulsify fats and help enzymes like lipase to act upon fats. During
emulsification, the bile salts convert bigger fat particles into smaller fat globules.
Pancreatic juice :-
It is an alkaline fluid (pH 7 to 8). It is transported to the
duodenum through the pancreatic duct. It contains water, mineral salts and a
variety of enzymes like : trypsin, chymotrypsin which are secreted in the
form of inactive precursors trypsinogen and chymotrypsinogen. The
precursors are activated by enterokinase of the intestinal juice, the amylytic
enzyme amylase, the pancreatic lipase (steapesin), carboxypeptidase and
nuclease. The enzyme trypsin hydrolyses proteins into polypeptides and
peptones.
Proteins ___________® polypeptides + peptones
Chymotrypsin hydrolyses peptide bonds associated with specific amino
acids like phenylalanine, tyrosine or tryptophan. It results in large peptides.
Proteins
chymotrypsin
large peptides
Carboxypeptidase is an exopeptidase. It attacks the peptide bonds at the
carboxyl end of the polypeptide chain resulting in di-, tripeptides and amino
acids.The pancreatic amylase converts starch into maltose. The lipase acts
on emulsified fat (triglycerides) and hydrolyses them into free fatty acids and
monoglycerides. Monoglycerides may be further hydrolysed to fatty acid
and glycerol.
As a result of digestion, all macromolecules of food are converted
into their corresponding monomeric units. Carbohydrates are broken into
monosaccharides such as glucose and fructose. Proteins are hydrolysed into
amino acids. Lipids get broken into glycerol and fatty acids. The simpler
organic molecules along with minerals, vitamins and water enter into body
fluids through the villi.
The villi are small microscopic finger-like projections. Each villus is
an absorbing unit consisting of a lacteal duct in the middle surrounded by fine
network of blood capillaries. While the fatty acids are absorbed by the lymph
duct, other materials are absorbed either actively or passively by the capillaries
of the villi.
From the lumen of the alimentary canal absorbed food materials are
carried to the liver through hepatic portal vein. From the liver, materials are
transported to all other regions of the body for utilisation. This conversion of
food into energy and cellular organisation is called as assimilation.
Obesity is the storage of excess of body fat resulting in a significant
impairment of health from a variety of diseases, notably hypertension,
atherosclerotic heart disease and diabetes.
A level of 10% above the standard weight, for subjects of same age and sex, is considered as obese. The degree of obesity is assessed by the body mass index (BMI). It is calculated as weight in Kg divided by the square of height in meters. For example, a 70 Kg person with a height of 180 cms would have a BMI of
21.6 (70/1.82). Normal BMI range for adults is 19 – 25. Men and women
having BMI values above this range are considered obese
Obesity may be due to genetic reasons, increased appetite leading
to excessive intake of food than is needed by the body, endocrine causes
and / or metabolic disorders.
