|
Causes of injuries due to physical activity
The main soft tissue elements of
the musculoskeletal system are muscles
,
tendons, and ligaments. They differ in function and structure as follows.
Muscles are contractile elements that
respond to electrical stimulation and neural discharge.
They move bones and produce motion. The contractile protein fibrils
transmit their forces through muscular connective tissue. This is a
network of interlacing tissue between the bundles of muscle fibers. The
muscular connective tissues converge onto terminal tendons thus transmit
all forces of muscular fibrils onto tendons, which are anchored onto
bones.
Tendons do not contract. They act as
links between muscles
and
bones. They are tough and
compact structures that can transmit large mechanical forces per
relatively small cross sectional area. A tendon is wrapped with a closed
sac of fluids that allow the tendon to slide on smooth curved surfaces
thus transmitting muscular forces into different directions.
Ligaments
share the same properties of toughness
with
tendons. They bridge bones, prevent disassembly, allow limited degree of
motion, and stabilize joints. They are only connected to bones, on both
ends. Shrunk and tight ligaments result from limited range of mobility.
This impedes joint usage and, if not treated soon, will lead to loss of
joint function.
Structural soft tissues elements
are injured when stretched beyond their maximal limits or traumatized by
compression against solid objects such as in joint dislocation or impact
accidents. The reaction of soft tissue to injury ranges from inflammation
to total structural disruption. Injuries to these structures due to
physical activity are caused by the following:
Excessive forces that exceed the body’s ability
to resist cause imbalance, regardless of the direction of action.
Lack of warm-up leads to inability of the neuromuscular
system
to coordinate muscles
to
resist forces that could otherwise be resisted had the warm-up been done.
Forces that act in directions that could not be opposed, by the natural course of
action of muscles
and
joints, cause imbalance. Lifting from the floor without bending the knees
put forces perpendicular on the vertebral spines and may cause disc
slipping, ligament sprain
, and
muscle or tendon strain.
Unfit body fails to coordinate muscular
efforts to maintain balance. Lack of regular physical activity undermines
the integrity of the autonomous nervous system, which control respiration,
circulation, and arousal
.
Inactivity also undermines the integrity of the voluntary nervous system,
which control muscular balance, and muscular and skeletal strength that
support the body under stress.
Lack of acquaintance with proper lifting techniques. The leverage actions of
the joints account for amplification of forces of moving bodies.
Moving the head, for example, amounts for an equivalent force plus
a torque at the lower back or feet, depending on the distance
between
the head and lower back and feet, respectively. The generated torque
eludes many people and can cause injuries and fall.
Watch a young toddler sustain sudden fall due to unexpected
movement of the head.
|
