1. Musculoskeletal Disorders (MSDs)
#1 Hazard in ON in all sectors, including mining.

2. Part 1: What are MSDs?

3. Musculoskeletal System Components
The musculoskeletal system includes:
Muscles, tendons and tendon sheaths
Joints and ligaments
Spinal column and discs
= Soft Tissue
Key Message: Basic introduction to the body systems that can be affected
Muscles: Support and move our joints
Tendons: Very strong fibers that attach muscles to bones. Allows our muscle forces to be converted into movement of the body
Tendon sheaths: Membrane that surrounds the tendon and helps movements to be smooth and fluid.
Joints: Connection point of several bones to give us a range of movement options
Ligaments: Strong fibers that connect bones to other bones. Provide support and stability to the joint. Can be stretched to the point where they permanently change length. This reduces stability of the joint.
Spinal Column: Body vertebrae stacked one on top of another in the trunk. Provides structural support to the body and attachment points for trunk muscles
Disc: Shock absorber between two discs. Facilitates motion between spine vertebrae.

4. Why MSDs happen? Injury repeated exertion time
MSDs can result from repeated loading
time
Tissue load
Injury
repeated exertion
Great visual of how work-related MSDs progress
Cumulative movements of high risk tasks, over time…..
Age 32 on, the bodies tissue tolerance starts to decrease, we continue to do the same, or more demands of the job, eventually the tissue will break
Ageing population, the worker who has done his job for 20 years all of a sudden his shoulder gets tendonitis…..tissue tolerance has changed.
We must work with the older body, understand the physiology, try not to wear it out at a lesser demand

5. Part 2: MSD Signs and symptoms

6. What should I look for? Signs:
redness, heat, swelling, reduced movement
Symptoms:
pain, discomfort, weakness, tingling, numbness, sleep interruption
taking anti-inflammatory medication
KEY MESSAGE: What should I look for and how do I know the severity of an MSD
Most common sites affected by MSD’s are low back, neck, shoulders, elbows, wrists but can also show up in mid-upper back, hips, knees, ankles, hands.
Typically, there is a gradual onset of the symptoms with worsening over time. Sometimes, an acute injury will not fully heal itself, which then leads to worsening symptoms of pain over time.
Signs can be physically seen and observed by the person or someone else: redness, heat, swelling, reduced movement
Symptoms can only be felt by the inflicted person: pain, discomfort, weakness, tingling, numbness

7. Stages of MSD Progression
Experience symptoms at work but can continue to work
Symptoms decrease with rest
Signs and symptoms come and go more frequently
Likely to experience symptoms after work
Symptoms & Signs do not leave
No longer able to work
Disturbed sleep
KEY MESSAGE: Most MSDs are at stage 3
What is the progression of an MSD - Recognize
Sleep is VERY important
Stages:
Experience symptoms at work but can continue to work. Symptoms decrease with rest.
Signs and symptoms come and go more frequently and present after work. Pain and other symptoms may interrupt sleep
Pain, aching and fatigue even at rest. No longer able to work. Sleep disturbance is common.

8. Reporting MSD Signs and Symptoms
If you have recognized a MSD sign or symptoms or if you have experienced daily pains and strains, talk to a supervisor, start the MSD investigative process…
Can’t prove when or where an MSD has started….cumulative micro tears…over time over doing a high risk task
So important to do RA – omit all HIG MSD risk tasks, the only responsibility of an employer
Prove that there are NO high risk MSD tasks….
Focue on the task (movement) not the individual worker

9. Employee Discomfort Survey (EDS)
Hand out the EDS survey (MSD Guideline ON, 2005)
Anonymous – fill in the areas that are experiencing symptoms at the end of your shift….not a diagnostic tool
Supervisors collect the data – summarise finings – subjective data as to where the human machine is breaking down
Do another survey in 6 months after risk assessments have been performed, eliminating all HIGH risks…

10. Part 3: Recognizing MSD Hazards

11. Causes of MSDs Primary risk factors: • High Force • Awkward Postures
• Repetition
KEY MESSAGE: There will be three primary risk factors to review: force, posture, repetition
Can you give me examples of high force in your work day?
Push/pull carry lift…..

12. Force – Primary Risk Factor
High Forces: Overexertion occurs when the force required exceeds the tolerance of the body’s tissues. The greater the force required, the greater the risk of injury
Examples in Mining?
MMH, pushing, pulling, carrying
KEY MESSAGE: High Force can lead to an increased risk of MSD
Excessive force may cause acute injury or chronic injury through fatigue. Excessive or sustained force can cause fatigue of the muscles, which can wear down the musculoskeletal system.
Better to push than pull
Lifting limits at work?
NIOSH lifting standard: 23kg maximum lift – doesn’t take into account the real world

13. Posture – Primary Risk Factor
If a task involves taking a static or awkward posture, the risk of pains and strains increases.
Awkward Posture - Involves bending or twisting away from a neutral posture.
Static Posture - The same position held for a long period of time; can be either a neutral or awkward posture.
PICTURE: Suggest using something more relevant to mining industry
KEY MESSAGE: What constitutes a posture that may lead to increased risk of MSD?
A neutral posture is a position taken near the middle of the body’s full range of motion.
It does not involve any overextension of motion. It is the most desirable posture as it allows maximum efficiency with the least amount of energy.
Awkward posture: A deviation from neutral is considered an awkward posture.
As the joint moves away from the neutral midline, the strain on ligaments and tendons increases.
When in a stretched position, the ligaments and tendons lose their ability to protect joints.
Static Posture: A static posture is a posture that is held for a long period of time. The risk of a static posture is that it requires constant muscle contraction, decreased blood circulation and eventually a build up of metabolic waste products in the cell that can further damage the muscle.

14. MSD Hazards – Awkward Postures
Awkward postures to look out for…
Mining examples – driving LHD trucks, neck rotated, back in flexion high freq.
Lifting, holding drills above your head
More?

15. Repetition – Primary Risk Factor
Repetition is the number of times a task or similar motion is performed per minute, hour, shift, or day.
Highly repetitive tasks can cause muscle fatigue, damage to other tissues and, eventually, pain and discomfort
KEY MESSAGE: Repetition is the third primary risk factor
Repetitive tasks which require one to use the same muscle groups over and over again are at a high risk for MSD development. The lack of time between tasks develops fatigue in the muscles which may increase their likely hood of injury
One solution…..job rotation – use of different muscle groups.
Guidelines:
Duty Cycle = % repetition /day
30 cycles per minute
2 hours/day
Combination of all 3 primary risk factors….
HIGH FORCE+AWKWARD POSTURES +REPETITION…..VERY HIGH RISK FOR AN MSD

16. Other MSD Risk Factors Secondary risk factors: Contact stress
Vibration
Temperature (too hot or too cold)
Work organization – (Mining piece work)
Work methods
Contact stress is stress developed from physical contact with a surface: boots on an uneven floor, wrists resting on a keyboard etc.
There are two types of vibration: local and whole body. An example of local vibration is Hand-Arm Vibration Syndrome (HAVS or white
finger) which develops from excessive vibration in the hands (often from hand-held power tools) that constricts the blood vessels in the fingers. Whole-body vibration (WBV) is often experienced in large mobile equipment.
The vibrations may damage and stress the musculoskeletal system, especially the lower back region.
Cold temperatures cause muscles to contract and become less malleable,
presenting a risk of injury. High temperatures can cause fatigue to set in quickly.
Work organization factors include job stress or work pacing which can increase strain. Mining risk = piece work….$ more important than health….Culture!
Work methods focus on how efficiently the job is set up.
Examples?

17. MSD Risk Assessment Duration / Time
Use the MSD Guideline “Risk Assessment” tool to perform an investigation with all workers – to brainstorm solutions….
Participatory Ergonomics
Guidelines:
Duty Cycle = % repetition /day
30 cycles per minute
> 2 hours/day
You may deem a task is repetitive….case by case

18. Reporting a MSD Hazard
If you have recognized a MSD High risk factor within your job tasks, talk to a supervisor about it. Get involved with the assessment, find solutions!
Reporting must follow with immediate investigation using the tools.
Letting it slide, reporting as a medical does not solve the “root cause” – if the high risk task is still there – the human machine will keep breaking down.
This step is the GAP in MSD prevention.
WSIB stats are not true as medical aid increases frequency count….

19. Part 4: Ergonomic Solutions
NAPO MMH solutions clip

20. Ergonomics – Controlling Risk Factors
Ergonomics ‘fitting the task to the worker’
Removing or decreasing high risk factors from a worker’s daily tasks does not have to be expensive or complicated.
Some examples of solutions:
• Adjustable work benches to match needed height for each worker
• Reorganizing work materials to reduce twisting and lifting
• Using anti-vibration hand tools to reduce vibration
Changing postures
Taking micro-muscle breaks
KEY MESSAGE: An introduction to the science of ergonomics
Ergonomics is “the scientific discipline concerned with understanding interactions between humans and other elements of a system (i.e.tools, equipment, products, tasks, and environment). The purpose of ergonomics is “to optimize human well-being and overall system performance by controlling the risk factors associated with MSDs” (i.e. fit the task to the worker).
Examples of easy solutions:
• Adjustable work benches to match needed height for each worker
• Reorganizing work materials to reduce twisting and lifting
• Using anti-vibration hand tools to reduce vibration

21. Reducing MSD Exposure
There are several steps that you can take to reduce your MSD exposure:
Report MSD hazards
Work as a group to discuss solutions
Warm up your body for the day
Use the correct lifting technique
KEY MESSAGE: These are things that the worker can do to reduce their exposure to MSDs
The supervisor’s role: Once hazards are reported, supervisors can take steps to either eliminate the hazard (i.e. adjustable work benches) or reduce the hazard (i.e. job rotation) or provide PPE to limit exposure to the hazard.
Use your “core muscles” – retrain biomechanics

22. Lifting Biomechanics
Improper lifting techniques require the muscles of the back to generate 10 times the weight being lifted!
How can the forces on the back be lowered?
Use your CORE muscle ALWAYS, wide stance, arch low back
Must change our adult habits – ie. we only have 5000 “bad lifts” in a lifetime….we don’t want to use them up before retirement!
Decrease wear and tear – use your knees, stomach – because we WILL have many bad lifts (getting boxes from the trunk of our cars) that we will not be able to put our knees into the equation – our backs will be ready due to less wasted lifts on silly things such as paper and pens.
It takes 28 days to change a habit (Dr. Phil) – must talk/walk through the Lifting 101 for a month – then it becomes automatic for us.
Lifting Tips
Factors to take into consideration – dimensions/properties of the load, characteristics of the lifter, # repetitions,
Keep your natural curve (lordosis) when lifting.
Obtain a wide stance – feet wider than shoulder width.
Use your abdominal/oblique core muscles at all times
Creeping - When driving, sitting for any length of time, walk around, and re-set tissue clock before lifting.
Get out of the car at least once/hour. Discs are at a lengthened, weak position – high risk for injury!
Don’t lift heavy items early in the a.m. – no flexion….
Disc bending stresses increased by 300%
Ligaments by 80%
Adams, Dolan, Hutton (1987)
Anderson & Ortengren (1974)
110 º sitting posture – less force/load than standing posture – don’t stay at 90º, move around, feet up on desk…..
5. Kelsey (1975) Variable work- not too much of anything have merit in reducing LBD
6. Push rather than Pull
7. Unloading boxes : use boxes with handles
Limit max. weight – standards, policies Trunk: slight bend knees, keep lordosis, contract core

23. Personal Protective Equipment
Personal Protective Equipment (PPE) is not the best solution but may be appropriate in some situations.
Examples:
Effective:
• Well-designed “anti-vibration” gloves
• Kneepads for kneeling work
• Anti-fatigue matting
• Shock-absorbing insoles
KEY MESSAGE: There are PPE solutions that can contribute to reducing exposure to MSD hazards.
PPE Controls are used as a last resort. Some PPE may not be beneficial to the workers. There are some devices which may reduce the risk of developing an MSD, while others may do nothing, or even increase the risk of injury.
A 1994 NIOSH report, “Workplace Use of Back Belts”, concluded:
Back belts do not prevent injuries amoung uninjured workers nor are they protective for those who have not been injured.
Ineffective:
• Back belts
• Wrist supports or splints

24. Lifestyle Factors
Proper exercise and nutrition help keep the musculoskeletal system operating at its peak, and thus helping to prevent injuries
Stretch/Exercise: 30 minutes each day
Sleep > hours ideal
Good Nutrition
KEY MESSAGE: Fit and healthy workers are strong workers
Regular exercise keeps the musculoskeletal system strong and adaptable, and exercise and proper nutrition help workers to maintain a healthy weight, which reduces strain on the musculoskeletal system.
Any movement – walk, breathe – doesn’t have to be high intensity
Drink lots of water

25. Suggesting a Solution
If you have recognized a way to reduce your exposure to an MSD risk factor within your job tasks, talk to a supervisor about it.

26. Part 5: Testing our Knowledge

27. Identify the MSD hazards that exist in each of the pictures
ACTIVITY
Identify the MSD hazards that exist in each of the pictures
Activity
Have the participants look at each picture. What risk factors
(primary or secondary) can you identify? What controls can be
taken (engineered, administrative, PPE)?

29. Recognizing MSD Other hazards that may cause MSDs Contact stress
Local or whole body vibration (WBV)
Cold temperatures
Work organization
Psychosocial
Individual characteristics
LHD Load-Haul-Dump vehicle
40 degree AP with neck ~ 88% of shift!

30. Some suggestions:
Picture 1, housekeeping under conveyor
• Force - holding hose, pulling hose, back-pressure from water
• Posture - awkward (neck, wrist), twisted back, static
• Repetition - repeating job, dependent on length of conveyor
system
• Secondary - vibration (hose)

32. Picture 2, forklift operator:
• Force - controls - hand controls, steering wheel
• Posture - awkward, twisted, static (neck, back)
• Repetition - controls, twisting (dependent on number of pallets
being transported)
• Secondary: vibration (HAVS, WBV)
• Contact stress (hand controls, steering wheel)

33. Resources
The Provincial MSD Prevention Guideline and Toolboxes, are available for download at WSN’s website.
Ask your WSN Consultant Trainer for more tools, assistance.