Body Mechanics
Unit 103
Objectives
• Recognize principles of appropriate body
mechanics, including safety, precautions, body
alignment, and body mechanics.
103.1
Body Mechanics
• efficient use of body as
a machine
103.1
Body Mechanics
• Efficient use of body as a machine
• Purpose of good mechanics
– promotes good musculoskeletal function
– reduces required energy
– promotes balance
– promotes safety of patient and healthcare
worker
Terms
• Alignment
– having parts in proper
relationship to each
other
Cervical
Thoracic
Lumbar
Sacrococcygeal
Terms
• Balance
– steady position
Terms
• Base of Support
– area on which object
rests
Terms
• Gravity
– force that pulls object toward
center of the earth
• Center of gravity
– area on which mass of object is
centered
• Line of Gravity
vertical line that passes through
center of gravity
Terms
• Center of gravity and
balance
– for an object/person
to be in a stable
position, the center of
gravity must be above
the base of support
Posture
• position of body
• keep feet parallel,
flat on the floor,
shoulder width apart
• bend knees slightly
to avoid strain
– act as shock
absorbers
GOOD
BAD
Proper Posture
• pull buttocks in and
hold abdomen in, helps
keep straight back
• hold chest up and
slightly forward
• hold head erect with
face forward and chin
slightly in
GOOD
BAD
Body at Work
• use longest & strongest
muscles (legs)to provide
energy
• use internal girdle and make a
long midriff to protect
abdominal muscles
• keep feet apart for a wide
base of support
• push, pull or roll objects when
possible
Body at Work
• Bend at knees and hips, use leg muscles,
and keep back straight when lifting
Body at Work
• Avoid twisting and stretching muscles
• Rest between periods of exertion
Concepts of Moving a Patient or
Object
• Friction
– force that opposes
motion
• Force
– energy required to
accomplish movement
• Inertia
– tendency of an object
at rest to stay at rest
and an object in
motion to remain in
motion
Ouch!
Concepts of Moving
a Patient or Object
• Muscle
– produce forces that move levers
• Fulcrum
– a fixed point about which a lever moves
• example: elbow
Concepts of Moving
a Patient or Object
• Lever
– any one bone or
associated joint that
acts as simple machine
so that force applied to
one end tends to rotate
the bone in opposite
direction
Lever
Principles of Body Mechanics
• USE MIND THEN YOUR MUSCLES
– muscles act in groups to perform a function
– large muscles fatigue less quickly
– muscles are always slightly contracted
– stability is greater with a wide base of
support, and low center of gravity
– adjust work area (beds) to waist level when
possible
Principles of Body Mechanics
–
–
–
–
it is easier to push or pull than to lift
friction increases work, work on a smooth surface
changes in activity or position decrease fatigue
use body weight and mechanical devices to
decrease effort to include rocking or leaning
forward or back
– work close to object you are moving
– avoid twisting your body
Principles of body mechanics
• If lifting a heavy object ask for help.
• Keep feet 12” apart when lifting.
• Rules of good body mechanics apply to moving
objects and tranfering patients.
Knowledge Assessment
•
•
•
•
Define alignment and gravity.
Discuss center of gravity.
List considerations for a body at work.
List concepts of moving a patient or an object.