MUSCULOSKELETAL
DISORDERS
Work-related musculoskeletal
disorders
They are cumulative
(occur over
time and not a result of a single incident):
•Often occur when the physical demands of
work cause wear and tear
•Involve soft tissues such as muscles,
tendons, ligaments, joints, nerves, blood
vessels
Work-related musculoskeletal
disorders
They are not acute injuries such as:
•Broken bones
•Cuts
•Slips
•Falls
•Trips
•Motor vehicle accidents
•Being struck by or caught with objects
Hazards
Work operations are necessary in
many industries such as welding,
construction,
manufacturing,
maintenance, etc.

Welding has several hazardous
conditions for women and men in
these jobs.

WMSD Hazards
Worked-related musculoskeletal
disorders (WMSD) hazards such as:

awkward body postures,

lifting heavy equipment or materials,

static postures for prolonged periods,

awkward postures of the wrist, etc.
Common disorders







Back injuries
Shoulder pain/loss of range of motion
Tendinitis/Bursitis
Reduced muscle strength
White finger
Carpal tunnel syndrome
Knee joint diseases
WA State-funded compensable claims
1994-2004
Welders, Cutters, Solderers
By Nature of Injury
Other
13%
Sprains account for
more than 1/3 of the
compensable claims
among welders in the
State of Washington.
Neural
5%
Sprains
32%
Ill-Def
Symptoms
9%
Hearing loss
11%
Some of those could be
caused by hazardous
WMSD exposures.
Fracture/
Dislocation
14%
Contussion/
Cut/
Scratches
16%
WMDS hazards most common in
work
OFTEN, MORE THAN 1 RISK FACTOR IS PRESENT

Rigorous manual precision requirements
◦ High degree of uniformity

Awkward and static postures
◦ Difficult work position

Heavy lifting, difficult material handling
◦ Heavy objects, heavy welding equipment

Repetition
◦ High work intensity
Hazard Elements
Duration (how long?)
Frequency (how often?)
Intensity (how hard?)
Common postures adopted in
welding
Working in
front
Working at
ground level,
precision work
Working at
ground
level
Working at
ground level,
confined space
Working
above the
shoulders
Working above
shoulders,
confined space
‡From: Torner et al, 1991
Awkward postures in work
 Severe
torso
flexion
 Torso twisting
 Kneeling, squatting
 Bent wrists
 Neck
flexion/extension
 Shoulder
flexion/abduction
(separation)
POSTUR DUDUK
MANUAL HANDLING
HAZARD ERGONOMI & BIOLOGI
Hazard human error
MUSCULOSKELETAL DISSORDERS
Repetition of work
High Risk Repetition Rates by Different Body Parts
Body Part
Minute
Shoulder
Upper Arm/Elbow
Forearm/Wrist
Finger
Repetitions Per
More than 2½
More than 10
More than 10
More than 200
From Kilbom Å [1994]. Repetitive work of the upper extremity; Part II: The
scientific basis for the guide. Int J Ind Erg 14:59–86.