Together, the bones of the human skeleton support the rest of the body, and give
it the shape we all recognize. They also protect the vital organs and act as
levers enabling movement to take place. Less obviously, they manufacture blood
and store and distribute essential minerals calcium in particular. There are
four types of bone, classified by shape long, short. Oat and irregular.
Long bones each consist of a shaft with a knob al each end. The shaft is a
thick-walled tube of dense bone filled with yellow marrow, while the ends are
made of spongy bone covered by a thin layer of dense bone. Leg, arm and rib
bones are typical long bones.
Short bones are box-like structures made of spongy bone enclosed in a thin crust
of denser bone. They are formed in places such as the ankle and wrist where
strength is required along with a capacity for limited movement.
Flat bones have similar construction to that of short bones. Examples are the
shoulder-blades and the skull bones.
Any bones which do not fit into the other three categories are called irregular
bones. They include the bones of the face and the spinal column.
Spongy bone contains red marrow which produces blood cells. In children, the
shafts of long bones also contain this marrow; but in adults it is replaced by
yellow marrow which produces blood cells only when the body is under stress.
The bones are connected by joints, which fall into three categories: immovable,
slightly movable and freely movable. Immovable joints hold the bones tightly
together with tough fibrous tissue, as in the skull. Slightly movable joints
hold the bones together by a disc of cartilage, as in the spine. Freely movable
joints hold the bones together by a fibrous capsule containing a lubricating
fluid, as in the elbows and knees.
System: There are 206 major
bones in [he human body. In a living person bones are pliable structures consisting of proteins impregnated with mineral
substances. This combination gives properties of resistance to compression,
tension and a certain amount of elasticity.
Bones change dramatically in shape
and size with age and it is growth of bones that determines a person's adult
height. Here most of the individual bones of the skeleton are shown. Bones are
interconnected by means of joints, and there is great variation in the shape and
mobility of joints to suit their particular functions. For example, the joints
in the adult skull are usually fused together so that the bones of the skull
form a solid casing to protect the brain.
In the limbs where a great deal of
mobility is required, the bones are separated by joint cavities. Movable joints
are supported by ligaments and are moved and partly supported by muscles. The
vertebral column, or spine, surrounds and protects the spinal cord. The spinal
nerves emerge from small holes in the sides of the vertebral column.
Intervertebral discs lit' between the individual vertebrae. The largest discs
are in the lumbar region.
Structure of the Skeleton
- Cervical vertebrae
- Thoracic vertebrae
- Lumbar vertebrae
- Lumbar discs
- Deltoid muscle
The Skeletal System
Some Disorders of the Skeletal System
Aches, pains and stiffness in the bones and joints are a relatively common
symptom in adult patients. Each year some 20 million people in the United
Kingdom suffer from a skeletal disorder involving the loss of 40 million working
days a year.
Among adults, some 5 million people suffer from osteoarthritis. in which the
cartilage linings between the bones of the joint are worn away. Back pain alone
is the next most common disorder, followed by rheumatism, a general term for any
pain affecting the muscles and joints.
- Hospital nurses. More than 220.000 nurses in Britain suffer from back
pain each year—caused by bending over bedridden patients. This can be
eliminated by bending correctly.
- People in their mid-6os and upwards. Rheumatic disorders affect at least
40 per cent of men and women aged 65. Left untreated the disorders can
- Coal-miners, building workers and the like are prone to injuries which can
lead to rheumatic disorders.
Main Symptoms of Disorder of the Skeletal System
The following symptoms all have entries in the Symptom Sorter under the part
of the body affected.
If any of the following symptoms occur, a doctor should be consulted without
- Bruising, swelling or deformity of a bone, following injury, which may
mean that it is fractured.
- Joint pain.
- Fain in the lower back radiating into the buttock, thigh and leg can be a sign
of sciatica which, in turn, may indicate a more serious back disorder.
- Neck and shoulder pain.
- Acute pains in the limbs or joints of a growing child may indicate infection
such as osteomyelitis.
How to Help Prevent Skeletal Problems
- When lifting or carrying follow the advice given
Back Pain remedy.
- Always wear seat-belts in a car and a crash-helmet on a motor-cycle. Wear a
lightweight helmet when riding a bicycle.
- Always wear well-fitting, low shoes