MUSCULOSKELETAL MUSCULOSKELETAL DISORDERSDISORDERS
•Often occur when the physical demands of work cause wear and tear
•Involve soft tissues such as muscles, tendons, ligaments, joints, nerves, blood vessels
They are cumulative (occur over time and not a result of a single incident):
Work-related musculoskeletal Work-related musculoskeletal disordersdisorders
Work-related musculoskeletal Work-related musculoskeletal disordersdisorders
•Broken bones•Cuts•Slips•Falls•Trips•Motor vehicle accidents•Being struck by or caught with objects
They are not acute injuries such as:
Hazards 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 HazardsWMSD HazardsWorked-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 disordersCommon disordersBack injuriesShoulder pain/loss of range of motionTendinitis/BursitisReduced muscle strengthWhite fingerCarpal tunnel syndromeKnee joint diseases
By Nature of Injury
Sprains account for more than 1/3 of the compensable claims among welders in the State of Washington.
Some of those could be caused by hazardous WMSD exposures.
WA State-funded compensable claims WA State-funded compensable claims 1994-20041994-2004Welders, Cutters, SolderersWelders, Cutters, Solderers
Hearing loss11%
I ll-Def Symptoms
9%
Neural5%
Other13%
Sprains32%
Contussion/Cut/
Scratches 16%
Fracture/Dislocation
14%
WMDS hazards most common in WMDS hazards most common in workwork
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
OFTEN, MORE THAN 1 RISK FACTOR IS PRESENT
Hazard ElementsHazard Elements
Duration (how long?)Duration (how long?)
Frequency (how often?)Frequency (how often?)
Intensity (how hard?) Intensity (how hard?)
Working in front
Working at ground level
Working above the shoulders
Working at ground level, precision work
Working at ground level, confined space
Working above shoulders, confined space
‡From: Torner et al, 1991
Common postures adopted in Common postures adopted in weldingwelding
Awkward postures in workAwkward postures in workSevere torso
flexionTorso twistingKneeling, squattingBent wrists Neck
flexion/extensionShoulder
flexion/abduction (separation)
POSTUR DUDUKPOSTUR DUDUK
MANUAL HANDLINGMANUAL HANDLING
HAZARD ERGONOMI & BIOLOGIHAZARD ERGONOMI & BIOLOGI
Hazard human errorHazard human error
MUSCULOSKELETAL DISSORDERS
Repetition of work
High Risk Repetition Rates by Different Body Parts
Body Part Repetitions Per Minute
Shoulder More than 2½ Upper Arm/Elbow More than 10 Forearm/Wrist More than 10 Finger More than 200From Kilbom Å [1994]. Repetitive work of the upper extremity; Part II: The
scientific basis for the guide. Int J Ind Erg 14:59–86.