Anatomy, Posture and Body
Mechanics
Lesson 1
Outcome of this lecture;

By the end of this lecture,student should
know;
1.
2.
3.
4.
Definition of Ergonomics
The importance of ergonomics
Basic Anatomy
Musculoskeletal Disorder (MSD)
What is Ergonomics ?
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From Greek Word,
ERGO = “Work” and NOMOS = “Rules” or
“Law”
ERGONOMICS = “The Laws of Work”
Ergonomic in Al-Quran

Dan engkau sangka mereka sedar,
padahal mereka tidur; dan Kami balikbalikkan mereka dalam tidurnya ke
sebelah kanan dan ke sebelah kiri; sedang
anjing mereka menghulurkan dua kaki depannya
dekat pintu gua; jika engkau melihat mereka,
tentulah engkau akan berpaling melarikan diri dari
mereka, dan tentulah engkau akan merasa sepenuhpenuh gerun takut kepada mereka.

Surah Al-Kahfi ayat ke-18
OSHA definition

“… the science of “designing the job to fit
the worker, instead of forcing the worker
to fit the job”
“FITTING THE TASK
TO HUMAN”
Working definition: Balancing job
demands and limitation of the human body to get
optimum outcome
Worker
Capabilities
Job
Demands
Criteria good fit
between work and
worker
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•
•
•
•
Effectiveness
Ease of use
Comfort / discomfort
Health and safety
Quality of life
Center for Occupational
Ergonomics and Safety
Why Become Familiar with
Ergonomics?
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Learn to control the risk factors
Improve worker comfort,
productivity and safety
Lower the chances for
occupational injuries
Center for Occupational
Ergonomics and Safety
Objectives of
Ergonomics

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Makes job safer by preventing
injury and illnesses
Makes job easier by adjusting job
to the worker
Makes job pleasant by reducing
physical and mental stress
Saves money (RM…)
Center for Occupational
Ergonomics and Safety
Benefits of
Ergonomics
• Ergonomics helps to prevent
injuries
• Other benefits
– Improved quality of work
– Improved quality of life
– Reduced fatigue and discomfort
Center for Occupational
Ergonomics and Safety
OSHA 1994 Requirement
OSHA 1994 Objectives (Section 4c)
“To promote an occupational environment
which is adapted to physiological and
psychological need of workers”
 Indirectly refers to importance of
ergonomics in working environment
 Employer should not overlook on
ergonomics aspect in order to provide
healthy and save working environment to
their employees

Center for Occupational
Ergonomics and Safety
SAVE MONEY
Application of simple ergonomics
principles can reduce
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Worker’s compensation
Absenteeism
Employee turnover
Product defects
Error
Earn money for business
• Applying ergonomics principles on
products can improve sales
Center for Occupational
Ergonomics and Safety
Iceberg Analogy
Accident Cost
Direct Costs
•Medical Payments
•Compensation
Down-time
Overhead $ while work disrupted
Breaking in substitute
Indirect or Hidden
Costs
Efficiency due to
break-up of crew
Loss of production
Loss of good will
Supervisor time to investigate
Damaged tools/equipment
Overtime to make up production
Failure to meet deadline/fill orders
Hiring costs
Lost time by fellow workers
Win-Win for
Employer / Employee
Employer
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Higher production
Higher quality
Increase profitability
and competitiveness
Lower Compensation
cost
Center for Occupational
Ergonomics and Safety
Employee
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Safe working
conditions
Career longevity
Quality of life
Morale
Employee Benefits
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Quality of life
Fewer pain, ache and
injuries
Career / employment
protection and longevity
Jobs more intuitive
Less fatigues
Human Body is a Mechanical System
Skeleton
Asimo
Robocop???
Functions of Skeleton and Muscular
Systems
SKELETON
 Support
 Protection
 Movement
 Homopoiesis (certain
bones produce red
blood cells – tulang
sum sum)
MUSCLE
 Produce movement
 Maintain posture
 Produce heat to
maintain body
temperature.
Analogy Human and Tent
Fabric = soft tissue
Skeleton
Muscles
Ligaments
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Stressful when body mass
depends on soft tissues
rather than bone.
Ligaments able to resist high
tensile forces.
Ligaments protects the joints
by limiting the range of joint
movement and resist
sudden displacements
which might damage the
joint.
Static Muscle Contractions
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Static muscle
contractions lead to
fatigue (lenguh)
The muscle must carry
out static work to
maintain the shape of
spine.
Pain Receptors
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Can be stimulated
by chemical,
thermal or
mechanical
stressors.
Can be reflective.
Anatomy of Spine and Pelvis Related
to Posture
The Spine
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Quadrupedal animals
and babies have single
spinal curve running
dorsally from pelvis to
head.
Adult humans, spine is
close to or below the
COG.
Intervertebral Disks

Acts as shock
absorbers and limit and
stabilize articulation of
the vertebral bodies.
Cervical Spine

Supports the weight of
the head and provide
conduit for neural
structures and
attachment points for
the muscles.
Pelvis
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Ring-shaped structure made
of three bones,
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Sacrum
2 innominate bones
Pelvis can be likened to an
arch which transfers the load
of superincumbent body
parts to the femoral heads in
standing and to the ischial
tuberosities in sitting.
Lumbar spine
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When a person is standing, the line of gravity
falls slightly behind the center of the hip joint,
which causes the pelvic to automatically tend
to tilt backward.
This position relieves the abdominal muscles
of a postural role and explains why these
muscles are relaxed in standing.
Summary
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Evaluation of physical workplace requires
basic knowledge on human anatomy nad
body mechanics.
Conditions for workplace to be safe;
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Body must be stable.
Observe postural behavior.
Musculoskeletal
Disorder (MSD)
Office Related
Ergonomics News on Our
Local Newspaper
How can we get Ergonomics Injury?
Primary Tool
Secondary Tool
 Equipment
 Machine
 Tools
 PPE etc
How to maintain?
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Human /
worker
Work
Scheduled
maintenance
Regular check out
Productivity
Materials /
Resources
Wear and tear to
primary and
secondary tools due
to work
MSD Analogy
Fatigue / Trauma
from job / non-job
related activities
Injury / MSD
Pain
Discomfort
Healing Valve
(Recovery time /
Reduced Physical
Stress)
Center for Occupational
Ergonomics and Safety
MSD
OCCUPATIONAL
INJURIES

Acute vs. Cumulative
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Classification of ergonomics
injuries – Cumulative (MSD)
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Chronic
Acute
Sub-Acute
Center for Occupational
Ergonomics and Safety
Musculoskeletal System
The musculoskeletal system is made up of the soft tissue
and bones in the body.
Bones: the load-bearing structure of the body.
Muscles: tissues that contract to create movement.
Tendons: tissue that connects muscles to bones.
Ligaments: tissue that connects bones to bones.
Cartilage: tissue that provides cushioning and
reduces friction between bones.
Nerves: the communication system that links muscles,
tendons and other tissue with the brain.
Blood vessels: tubes that circulate nutrients
throughout the body
Musculoskeletal System
Center for Occupational
Ergonomics and Safety
Musculoskeletal
Disorder (MSD)

Also know as:
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Cumulative Trauma Disorder (CTD)
Occupational Overuse Syndrome
Repetitive Strain Injuries (RSI)
Injury to soft tissues (muscle, joint, tendon,
nerve, blood vessel, cartilage)
Related to prolong exposure to ergonomics
risk factors
Musculoskeletal
Disorder (MSD)

Four Categories:
– Joint injury
– Muscle injury
– Tendon injury
– Nerve injury
Acute
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•
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•
MSD
Classification
Also call Strains and Sprains
Instantaneous (event driven)
Less than 2 weeks
Injury to connective tissue
caused by single forceful event
(e.g. lifting heavy object in
awkward position)
• Common to large body segments
(i. e. back, legs and shoulders)
Center for Occupational
Ergonomics and Safety
Chronic
MSD
Classification
• Developed 3 months and above
• Caused by overuse or repetition involving
muscles, nerves, tendons, ligaments, joints,
spinal disks, cartilage
• NOT cause by slips, trips, falls or other
accidents
• Exposure driven
• Injury to soft tissue caused by prolonged
exposure to multiple ergonomics risk factors
• Typically develop to small body segments
(i.e. fingers, wrists, elbows, necks)
MSD Symptoms
Symptoms
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•
Center for Occupational
Ergonomics and Safety
Muscle fatigue
Aching
Burning
Numbness
Stiffness
Tingling
Signs
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MSD Signs
Decreased range of motions
Decreased grip strength
Lost of function
Lost of balance
Deformity
Swelling
Cramping
Redness
Color loss
Common Occupational
MSDs
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Carpel tunnel syndrome
Cubital tunnel syndrome
Thoracic outlet syndrome
Raynaud’s syndrome (white finger)
Rotator cuff syndrome
DeQuervain’s disease
Tendinitis
Tenosynovitis
Trigger finger
Ganglion cyst
Carpal Tunnel Syndrome
Carpal
Tunnel
Syndrome
Carpal Tunnel Syndrome
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–
Impingement of the median nerve caused by irritation and
swelling of the tendons in the carpal tunnel
Carpal Tunnel Syndrome
Carpal Tunnel Syndrome
CTS Video
Back Pain
Back Pain
Back Pain
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Tips to relief back pain
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Sleep – back-friendly sleep
Select comfort mattress
Choose the right chair
Proper sitting during work
Stretch every 30 minutes
Practice safe lifting
Back exercise
Common Occupational
MSDs

Cubital Tunnel
Syndrome
–
Pressure on the
ulnar nerve when
the elbows are
exposed to hard
surfaces
Common Occupational
MSDs

Thoracic Outlet Syndrome
–
Compression of the blood vessels between the neck and
shoulder caused by reaching above shoulder level or
carrying heavy objects
Center for Occupational
Ergonomics and Safety
Common Occupational
MSDs
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Raynaud’s Syndrome
–
Also known as Vibration White Finger ; Blood vessels of
the hand are damaged (narrowed) from repeated
exposure to vibration for long periods of time
Center for Occupational
Ergonomics and Safety
Common Occupational
MSDs
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DeQuervain’s Disease
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Tendinitis
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Irritation of the tendon
Tenosynovitis
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Combination of tendinitis and tenosynovitis
Irritation of the synovial sheath
Ganglion Cyst
–
Accumulation of fluid within the tendon sheaths
Center for Occupational
Ergonomics and Safety
Eye Strain
Center for Occupational
Ergonomics and Safety
Eye Strain
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Signs and symptoms
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Sore, tired, burning or itching eye
Dry or watery eyes
Blurred or double vision
Headache or sore neck
Color fringes or afterimage when
look away from monitor
Increased sensitivity to light
Difficult shifting focus between
monitor and paper documents
Center for Occupational
Ergonomics and Safety
Eye Strain
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Relieve Eye Strain
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Take eye break periodically
Blink often to refresh your eye
Practice relaxation – “Palming Your
Eye”
Change the pace – 5 minutes rest
every one hour, or stand up and
move around at least once in one
hour
Center for Occupational
Ergonomics and Safety
The End